Methods of detecting T-cell activation and treating disorders associated with T-cell dysfunction

Methods of detecting activated T-cells involve monitoring levels of MUC-1 mucin expression at the protein and/or mRNA level. Compositions for modulating immune function contain compounds that modulate the expression or function of MUC-1. Methods of treating disorders associated an inappropriate state of T-cell activation involve contacting a T-cell with a compound containing an inhibitor of MUC-1 expression or function.

BACKGROUND OF THE INVENTION 
Mucins are large (&gt;200 kDa) glycoproteins with a high carbohydrate content 
(50-90% by weight) expressed by a variety of normal and malignant 
epithelial cells (Strous el al., Crit. Rev. Biochem. Mol. Biol. 27:57 
(1992); Devine et al, BioEssays 14:619 (1992)). Among the human mucins, 
MUC-1 is unique in its cell surface transmembrane expression (Gendler et 
al., J. Biol. Chem. 265:15286 (1990); Siddiqui et al Proc. Natl. Acad. 
Sci. USA 85:2320 (1988); Gendler et al, Proc. Natl. Acad. Sci. USA 84:6060 
(1987); Ligtenberg et al., J. Biol. Chem. 265:5573 (1990)). 
MUC-1 mucin contains a polypeptide core consisting of 30-100 repeats of a 
20 amino acid sequence (Gendler et al, J. Biol. Chem. 265:15286 (1990). 
The presence of large amounts of oligosaccharides attached along the 
length of the polypeptide core of MUC-1 mucin enhances its rigidity, 
resulting in large flexible rod-like molecules that may extend several 
hundred nanometers from the apical epithelial cell surface into the lumens 
of ducts and glands (Bramwell et al., J. Cell Sci. 86:249 (1986)). 
Adenocarcinoma patients with elevated serum MUC-1 mucin levels have higher 
numbers of T-cells expressing CD69, an early activation marker, than the 
patients with normal serum MUC-1 levels (Reddish et al., Cancer Immunol. 
Immunother. 42:303 (1996); Bowen-Yacyshyn et al., Int. J. Cancer 61:470 
(1995). It was hypothesized that patients with high serum MUC-1 levels and 
high numbers of CD69.sup.+ peripheral blood T-lymphocytes were in a state 
of T-cell anergy (Reddish et al, Cancer Immunol. Immunother. 42:303 
(1996)) similar to tumor infiltrating lymphocytes (TILs), which are 
CD69.sup.+ but appear to be "frozen" in an early activation state and 
unable to express normal interleukin 2 (IL-2) and IL-2R levels (Alexander 
et al., J. Immunother. 17:39 (1995); Berd et al., Cancer Immunol. 
Immunother. 39:141 (1994); Bamd et al, Proc. Natl. Acad. Sci. USA 86:7159 
(1989). 
Elevated levels of serum MUC-1 are associated with poor survival and a 
lower anti-cancer immune response of metastatic breast, colorectal and 
ovarian cancer patients following immunotherapy (Bowen-Yacyshyn et al, 
1995 Int. J. Cancer 61:470; MacLean et al, J. Immunother. 20:70 (1997)). 
Cumulatively, all of these results are consistent with an 
immunosuppressive role for MUC-1 mucin. 
Direct demonstration of an immunosuppressive role of cancer associated 
MUC-1 mucin came from recent work (Agrawal et al, Nature Med. 4:43 (1998)) 
showing that cancer associated, affinity purified, MUC-1 mucin and 
synthetic tandem repeats of MUC-1 polypeptide core inhibited human T-cell 
proliferative responses to polyclonal stimuli. The degree of inhibition of 
T-cell proliferation was directly proportional to the number of tandem 
repeats present on MUC-1 polypeptide core synthetic peptides. 
This inhibition was reversible by adding a 16 mer (&lt;1 tandem repeat of the 
polypeptide core) MUC-1 synthetic peptide (Agrawal et al., Nature Med. 
4:43), which confirms the role of the MUC-1 polypeptide core in the 
inhibition of T-cell responses and suggests an inhibitory mechanism, which 
involves cross-linking of a T-cell surface molecule. The observation that 
addition of exogenous IL-2 or anti-CD28 monoclonal antibody (mAb) reversed 
the cancer associated MUC-1 mucin induced inhibition of T-cell response is 
consistent with the mechanism of inhibition being anergy (Agrawal et al, 
Nature Med. 4:43). Our understanding of the immunoregulatory role of 
cancer associated MUC-1 mucin has revealed some of the intricate 
mechanisms tumor cells use to regulate immune responses for their enhanced 
survival. 
Aside from direct immmunomodulatory functions, other functions have been 
proposed for MUC-1 mucin (Gendler et al., Ann. Rev. Physiol. 57:607 
(1995)) which involve steric hindrance by the large glycosylated 
extracellular domain of cell-cell or cell-substratum interactions, 
remodeling the cytoskeletal network, or by down-regulating the activities 
of other molecules such as catenins, cadherins or integrins via signal 
transduction events (Yamamoto et al., J. Biol. Chem. 272.12492 (1997); 
Parry et al., Exp. Cell Res. 188:302 (1990). Its cytoplasmic tail is 
phosphorylated consistent with a transmembrane signal transduction 
function for MUC-1 (Pandey et al., Cancer Res. 55:40003 (1995); 
Zrihan-Licht et al., FEBS Lett. 356:130 (1994); Mockensturm-Gardner et 
al., Mol. Biol. Cell 7:434a (1996); Mockensturm-Gardner et al., Proc. 
Amer. Assn. Cancer Res. 39:375a (1998). 
Paradoxically, in previous studies MUC-1 mucin has been proposed to act 
both as an anti-adhesive as well as an adhesive molecule. The extended 
conformation of the extracellular domain of MUC-1 mucin may contribute to 
the anti-adhesive properties, resulting in reduced cell-cell aggregation 
and decreased adherence to extracellular matrix components in in vitro 
adhesion assays (Ligtenberg et al, 1992 Cancer Res. 52:2318; Wesseling et 
al, 1995 J. Cell Biol. 129:255; Wesseling et al., 1996 Mol. Biol. Cell 
7:565). Thus, MUC-1 mucin may protect cancer cells from destruction by 
natural killer or other immune cells (Hayes et al., 1990 J. Immunol. 
145:962; Ogata et al., 1992 Cancer Res. 52:4741; Zhang et al., 1997 Cell. 
Immunol. 66:158; van de Wiel-van Kemenade et al., 1993 J. Immunol. 
151:767). 
MUC-1 on cancer cells can also have adhesive features as it expresses 
carbohydrate structures that may be ligands for selectin-like molecules on 
endothelial cells (Baeckstrom et al., 1991 J. Biol. Chem. 266:21537; 
Hanski et al., 1993 Cancer Res. 53:4082; Sikut et al., 1996 Int. J. Cancer 
66:617; Zhang et al., 1997 Tumor Biol. 18:175; Zhang et al., 1996 J. Cell. 
Biochem. 60:538). MUC-1 mucin has also been shown to be a ligand for 
ICAM-1 (Regimbald et al., 1996 Cancer Res. 56:4244), another adhesion 
molecule involved in cell-cell interactions. MUC-1 can be shed from tumors 
and detected in serum (Hayes et al., 1985 J. Clin. Invest. 75:1671; 
Burchell et al., 1984 Int. J. Cancer 34:763; Boshell et al., 1992 Biochem. 
Biophys. Res. Commun. 185:1; Williams et al., 1990 Biochem. Biophys. Res. 
Conimun. 170:1331). The presence of soluble MUC-1 has been shown to 
inhibit adhesive interactions of rnigrating cells with endothelial cells 
(Zhang et al., 1997 Tumor Biol. 18:175) and thus could cause decreased 
recruitment of inflammatory cells to the tumor site. 
Although it has primarily been studied based on its association with 
cancer, MUC-1 is in fact expressed by a variety of normal tissues. A 
number of secretory epithelial cells, for example, express and secrete 
MUC-1 mucin. Although, this MUC-1 is highly glycosylated, and is therefore 
somewhat different than cancer-associated MUC-1, which is under 
glycosylated. 
Various glycoforms of MUC-1 mucin (similar to those of cancer associated 
MUC-1 mucin) have been found to be present in endometrium and in the serum 
of pregnant women. McGuckin et al., Tumour Biol. 15:33 (1994). During the 
menstrual cycle, the abundance of MUC-1 varies in human endometrium. 
Moreover, progesterone up regulates the transcription of MUC-1 and maximum 
MUC-1 expression appears in the implantation phase. Hey et al., J. Clin. 
Endocrinol. Metab. 78:337 (1994). 
Interestingly, it has been shown that high levels of progesterone present 
during days 14-28 of the menstrual cycle are associated with inhibition of 
CTL activity in the uterus. Consequently, the down-regulation of CTL 
activity may allow implantation of a semi-allogeneic embryo, which would 
be otherwise be rejected. White et al., J. Immunol. 158:3017 (1997). The 
mechanism of this T-cell down-regulation, however, is unknown. Indeed, the 
art is generally deficient in its knowledge regarding T-cell activation 
and de-activation. 
T-cell activation is an indicator of the immune state and thus is useful in 
monitoring a variety of diseases. For example, certain autoimmune diseases 
are etiologically linked to T-cell activation. Moreover, the ability to 
control the state of T-cell activation would, likewise, be useful in 
treating a wide variety of disorders. 
A need exists, therefore, in the art for the elucidation of a fundamental 
pathway involved in the regulation of T-cell activation. Provided such a 
pathway, certain diagnostic and medicinal agents will be made available to 
the art. The present invention, as detailed below, describes such a novel 
fundamental pathway as well as a variety of compounds for modulating that 
pathway, which have certain diagnostic and therapeutic applications. 
SUMMARY OF THE INVENTION 
It is therefore, one object of the invention to provide reagents and 
methods for determining the state of T-cell activation. According to this 
aspect of the invention, methods are provided which comprise detecting the 
amount of MUC-1 expression in a T-cell-containing sample and comparing 
said amount to a non-activated T-cell-containing control. In one 
embodiment, detection involves quantifying the amount of MUC-1 expression, 
preferably by contacting the sample with an antibody which is specific for 
MUC-1. In another embodiment detecting can be accomplished by contacting 
the sample with a polynucleotide probe which is capable of specifically 
detecting a MUC-1-associated nucleotide sequence. In yet another 
embodiment, methods of ascertaining global immune activation are provided. 
In a typical method, a sample is provided from a patient and the amount of 
MUC-1 present in the sample is detected. 
It is another object of the invention to provide methods for modulating 
T-cell activation, generally in the context of therapeutic methods. 
According to this object, methods are provided which entail treatment with 
compounds that either promote or antagonize the activity of MUC-1, thus 
altering the balance of T-cell activation in patients in need of such 
treatment.

DETAILED DESCRIPTION OF THE INVENTION 
Overview 
The present invention derives from the surprising observation that MUC-1, 
which heretofore was thought to be biologically important only in the 
context of certain disease states, plays a key role in the normal 
immunological response. Thus, when peripheral T-cells isolated from normal 
human blood, i.e., from non-cancerous patients, were monitored for the 
presence of MUC-1, only about 3-4% of these were found to express MUC-1. 
In contrast, upon mitogenic stimulation, approximately 80% of this same 
population of T-cells expressed MUC-1. This clearly shows a correlation 
between T-cell activation and MUC-1. These data are provided in more 
detail below in the Examples. 
As set out in detail below, MUC-1 mucin probably is involved in normal 
immune regulation, more specifically in T-cell activation/inactivation. 
Evidence supporting this conclusion includes: [1] newly synthesized MUC-1 
mucin is rapidly induced and appears on the cell surface of the majority 
of activated human T-cells; [2] the down regulation of MUC-1 mucin 
expression after the mitogenic stimulus is removed; [3] anti-MUC-1 mAb 
B27.29 (MUC-1-specific) inhibits the T-cell proliferative response; [4] 
new expression of MUC-1; [5] MUC-1 mucin is either shed or secreted into 
the supernatants of cultures of phytohemaglutanin (PHA) activated human 
T-cells; [6] soluble large molecular weight MUC-1 mucin inhibits T-cell 
proliferation and induces an anergy-like state that is reversible by IL-2 
or anti-CD28 antibody; and small molecular weight MUC-1 reverses MUC-1 
-induced anergy. Agrawal el at, Nature Med. 4:43 (1998). 
This conclusion also explains certain observations from the art that 
suggest normal functions for MUC-1. Specifically, it unifies the 
observations that: certain endometrial MUC-1 glycoforms vary during the 
menstrual cycle; progesterone up regulates the transcription of MUC-1, 
maximumally during implantation; and the association of high levels of 
progesterone during days 14-28 of the menstrual cycle with inhibition of 
cytotoxic T-cell (CTL) activity in the uterus. Since MUC-1 is herein shown 
to be a negative regulator of normal T-cell activation, it is likely that 
MUC-1 is acting to down-regulate CTL activity which would otherwise 
prevent embryo implantation through CTL-mediated rejection. 
Definitions 
As used in this specification, an "activated T-cell" is one that is in the 
following phases of the cell cycle: the G.sub.1 phase, the S phase, the 
G.sub.2 phase or the M (mitosis) phase. Thus, an "activated T-cell" is 
undergoing mitosis and/or cell division. An activate T-cell expresses cell 
surface activation markers, intracellular activation signalling 
molecules/cytokines, but are not yet dividing. An activated T-cell may be 
a T helper (T.sub.H) cell or a cytotoxic T-cell (cytotoxic T lymphocyte 
(CTL or T.sub.c)). Activation of a naive T-cell is initiated, for example, 
by exposure of such a cell to an antigen presenting cell (APC) (which 
contains antigen/MHC complexes) and to a molecule such as IL-1. The 
antigen/MHC complex interacts with a receptor on the surface of the T-cell 
(T-cell receptor (TCR)). Golub et al., eds. IIMMUNOLOGY: A SYNTHESIS, 
Chapter 2: "The T-cell Receptor" (1991). The skilled artisan will 
recognize that suitable accessory molecules may also be involved in 
activation of T-cells. Examples of such accessory molecules include B7.1 
(binds to CD28); B7.2 (binds to CD28); and ICAM-1 (binds to LFA-1). 
As used in this specification "memory T-cells," also known as "memory 
phenotype" T-cells, is used to designate a class of T-cells that have 
previously encountered an antigen but are now resting and are capable of 
being activated. Memory T-cells are T-cells which have been exposed to 
antigen and then survive for extended periods in the body without the 
presence of stimulating antigen. However, these memory T-cells respond to 
"recall" antigens. In general, memory T-cells are more responsive to a 
"recall" antigen, when compared with the naive T-cell response to antigen. 
Memory cells can be recognized by the presence of certain cell-surface 
antigens, such as CD45R0, CD58, CD11.alpha., CD29, CD44 and CD26, which 
are markers for differentiated T-cells. 
As used herein, the terms "anergy" and "immunosuppression" are used 
interchangeably and specifically incorporate all attributes ascribed to 
these terms, individually and collectively, by the immunological arts. 
Moreover, these terms are also used in some instances to denote the normal 
negative functions of MUC-1 that down-regulate the immune response. 
MUC-1 "antagonists" or "inhibitors," as used generically herein, 
specifically include inhibitors MUC-1 function, like competitive 
inhibitors and MUC-1 specific antibodies. 
The term "treating" in its various grammatical forms in relation to the 
present invention refers to preventing, curing, reversing, attenuating, 
alleviating, minimizing, suppressing or halting the deleterious effects of 
a disease state, disease progression, disease causative agent or other 
abnormal condition. 
Measuring T-cell Activation 
One aspect of the invention provides a method of determining whether a 
T-cell is activated. A typical method involves detecting the amount of 
MUC-1 expression in a T-cell-containing sample and comparing the amount of 
MUC-1 expression to a non-activated T-cell-containing control. 
The sample will be provided from a patient, who may be a human or non-human 
animal. Although the sample may be from any tissue origin, it typically 
will be derived from blood, lymph or tissue infiltrates. The sample 
specifically may comprise intact T-cells and/or some fraction thereof, 
such as protein or nucleic acid fractions. Isolated or enriched MUC-1 
protein and/or messenger RNA (mRNA) are specifically included. Tissue 
infiltrates include samples taken from the lungs, tumors, lymph nodes, 
pericardium, tissue transplant site and the thoracic and peritoneal 
cavities. Control samples may be obtained from healthy volunteers, whereby 
a standardized baseline may be established. 
Methods of detection include any detection system available that can be 
adapted to detecting MUC-1 expression. Of course, this can be accomplished 
by monitoring, for example, protein or mRNA levels, as discussed below. 
Some exemplary methods utilize antibodies for detecting the protein or 
polynucleotides for detecting the mRNA. Samples are generally controlled 
for relative numbers of T-cell by using detection agents in parallel, 
which detect all T-cell, or specific subsets of them. For example, 
antibodies directed to CD4 and/or CD8 could be used to normalize for total 
(when used together) or specific subsets of T-cell (used separately). In 
the case of kits involving detecting mRNA, known housekeeping genes can be 
used as a standard, since they have relatively constant levels of 
expression. 
In a more general sense, the activation of T-cells is indicative of 
activation of the immune system in general. Since MUC-1 expression, 
transport and release from the cell surface are all increased upon T-cell 
activation, shed MUC-1, for example, will correlate with T-cell 
activation, and thus global immune activation. Hence, general immune 
activation may be ascertained by providing a sample from a patient who is 
suspected of suffering from a relevant immune alteration and measuring the 
amount of soluble MUC-1. In this case, the sample will preferably be 
T-cells derived from blood, lymph, and the like. 
It is noted that the use of MUC-1 as a marker for T-cell activation is not 
inconsistent with its general role as an immune down-regulator. The data 
show that MUC-1 is only expressed by activated T-cells and it exerts its 
negative effect on T-cells only after it has reached the T-cell surface, 
presumably in sufficient quantity to induce some cross-linking. An example 
of a similar mechanism is CTLA-4 which acts similarly. Thus, while mRNA 
levels or intracellular levels of MUC-1 will probably be most useful in 
diagnostic applications, cell surface MUC-1 may also be used in this 
manner, especially if monitored over time. 
Compositions and Kits for Detecting T-cell Activation 
In general, the methods may be qualitative or quantitative. The qualitative 
methods may be adapted to assemble kits which may be used in the clinical 
laboratory or even the clinician's office. One such kit would contain some 
means for immobilizing T-cells, for instance T-cell-specific antibodies 
(e.g., antibody to T-cell receptors) bound to a dish or a dipstick, a 
solution for washing away the non-T-cell components, a MUC-1-specific 
antibody, and some means for detecting the MUC-1-specific antibody. One 
method of using the kit would include exposing the T-cell-containing 
sample to the immobilized T-cell-specific antibody, washing the sample to 
remove non-T-cell material, exposing the washed sample to MUC-1-specific 
antibody and detecting the MUC-1 specific antibody. The MUC-1-specific 
antibody can be detected, for example, by providing it in a form 
conjugated to an enzyme which utilizes a chromogenic substrate. 
Alternatively, a secondary, enzyme-linked antibody can be used. To provide 
for a control, prior to exposure of the sample to the T-cell-specific 
antibody, a white blood cell count can be done whereby a specific number 
of these cells is used as a sample. 
Quantitative methods for detecting proteins include radioimmunoassays 
(RIAs), enzyme-linked immunosorbant assays (ELISAs), Western blots, 
fluorescence activated cell sorting (FACS), immunohistochemistry. 
Quantitative methods for detecting mRNA include reverse 
transcription-polymerase chain reaction (RT-PCR), Northern blotting, 
chemical (non-enzymatic) amplification reaction. 
Antibodies may be labelled using a variety of techniques known to those in 
the field. Exemplary labels include enzymes, fluorescent markers and 
radionuclides. These are well known in the art. 
Methods of detecting mRNA, as known in the art, have the common feature of 
contacting a sample with a probe which comprises a polynucleotide encoding 
a MUC-1-associated nucleotide sequence. MUC-1-associated nucleotide 
sequences include those which actually encode MUC-1 (and their complement) 
and sequences associated with MUC-1 expression, including introns and 5' 
and 3' untranslated regions. Preferred probes are situated at or near the 
5' end of the gene. 
The polynucleotide probes may be RNA or DNA, but they are preferably 
deoxyribo polynucleotides. Some more preferred polynucleotides are 
oligonucleotides from about 15 to about 30 nucleotides in length, most 
preferably about 17 to about 23 nucleotides. Probes will be based on the 
native MUC-1 sequence, which is known in the art. 
Therapeutic Rationale 
Previous observations that cancer-associated MUC-1 mucin inhibits human 
T-cell proliferative response (Agrawal et al., Nature Med. 4:43 (1998)) 
and the present data showing that MUC-1 mucin is transiently expressed on, 
and shed or secreted by, activated human T-cells, clearly indicates that 
MUC-1 mucin plays an important regulatory role in an immune response. In 
addition, the observations that MUC-1 mucin can present multiple 
functional domains e.g. anti-adhesion, pro-adhesion as well as inhibit 
T-cell proliferative response (Agrawal, Nature Med. 4:43 (1998); 
Ligtenberg et al., Cancer Res. 52:2318 (1992); Wesseling et al., J. Cell 
Biol. 129:255 (1995); Wesseling et al., Mol. Biol. Cell 7:565 (1996)), are 
further consistent with the present conclusion that MUC-1 expression on 
T-cells plays an important homeostatic function. In fact, it is likely 
that MUC-1 mucin expression in activated T-cells actively terminates 
T-cell responses by down regulating their proliferation and, moreover, 
MUC-1 may serve a role in lymphocyte trafficking due to its adhesion 
and/or anti-adhesion properties. 
Without being bound by a particular theory, the inventors hypothesize that 
MUC-1 expression is essential for T-cell activation as it is synthesized 
and appears on the cell surface. Once on the cell surface, however, MUC-1 
seems to exert its negative effects The data below suggest that the key to 
this negative effect is crosslinking of MUC-1 on the cell surface (and 
likely, thereby, crosslinking a receptor to which it binds). 
MUC-1 is made up of 60 to 100 tandem repeats, which have been linked to the 
activity of the molecule. Prior data show that exogenously added large 
molecular weight MUC-1 (having many repeats) can cause T-cell 
inactivation, and that this can be reversed by treatment with small 
molecular weight MUC-1 molecules (having 1-3 repeats. If each MUC-1 repeat 
binds a receptor molecule on the T-cell surface, the large molecular 
weight versions would effectively crosslink those individual receptors. On 
the other hand, molecules having 1-3 repeats probably act as competitive 
inhibitors, competing with larger MUC-1 molecules for receptor binding 
sites and thereby preventing effective crosslinking of the putative MUC-1 
receptor. 
As T-cell activation progresses and MUC-1 accumulates to higher levels and 
is shed, it is believed that each molecule becomes available to interact 
with numerous MUC-1 receptors, which induces crosslinking and, thus, 
invokes the immuno-suppressing activity of MUC-1. This, however, can be 
induced artificially. Further, data presented below show that, while 
bivalent IgG anti-MUC-1 antibodies have some down-regulatory effect on 
T-cell activation, this can be amplified by adding a secondary antibody or 
by using a hexavalent IgM antibody instead. In addition, our prior 
experiments demonstrated that multiple tandem repeats are important for 
inducing T-cell inhibition by soluble MUC-1. Either way, the key to 
MUC-1-mediated immunosuppression seems to be crosslinking. 
Accordingly, both inhibiting and promoting MUC-1 activity will be useful in 
treating diseases associated, on the one hand, with illegitimate or 
clinically premature T-cell deactivation and, on the other hand, with 
illegitimate T-cell activation. The former conditions are treatable using 
MUC-1 antagonists and the latter are treatable using MUC-1 enhancers. 
The invention contemplates modulators of MUC-1 activity that fall into two 
categories, based on the net result of their application to a T-cell. The 
first category includes MUC-1 antagonists, alleviate T-cell anergy or 
immunosuppression and, therefore, have a net overall immuno-stimulatory 
effect on these cells. These inhibitors reverse the natural negative role 
of MUC-1, which down-regulates the immune response. Such antagonists are 
useful in treating patients suffering from conditions characterized by 
T-cell anergy or immunosuppression, and in treating any other conditions 
where induction of a T-cell response is desired. 
The second category of MUC-1 modulators has very nearly the opposite effect 
of the first category. These modulators, or MUC-1 enhancers, rather than 
antagonising the negative effects of MUC-1, actually facilitate them. In 
other words, they enhance MUC-1-induced down-regulation of the immune 
response and, thereby, they induce anergy or immunosuppression; they are 
generally immunosuppressive. 
MUC-1 Antagonists 
As indicated, one class of MUC-1 modulators include antagonists of MUC-1. 
Some MUC-1 antagonists interfere with the binding of MUC-1 to its surface 
receptor, thereby disrupting the crosslinking required for the negative 
effects of MUC-1. MUC-1 antagonists generally act by binding either MUC-1 
or its receptor, but in all cases they prevent MUC-1-mediated 
immunosuppression, probably by preventing cross-linking. This disruption 
can occur, for example, by competitively inhibiting the binding of MUC-1 
to its receptor. 
The antagonists can be derived from the MUC-1 molecule itself, and they can 
be MUC-1 peptide derivatives, based on the native MUC-1 core repeat 
sequence. In one embodiment, the peptide would include portions of the 
extracellular tandem repeat region of MUC-1, which includes repeats of the 
amino acid sequence (SEQ ID NO: 2) DTRP (Asp-Thr-Arg-Pro). Preferably 
these tandem repeats include the sequence (SEQ ID NO: 3) SAPDTRP 
(Ser-Ala-Pro-Asp-Thr-Arg-Pro). 
A MUC-1 "core repeat," "core sequence" or "MUC-1 core" as used herein 
generally refers to that present in the native MUC-1 molecule, which 
comprises the 20 amino acid sequence (SEQ ID NO: 1) PDTRPAPGSTAPPAHGVTSA 
(Pro-Asp-Thr-Arg-Pro-Ala-Pro-Gly-Ser-Thr-Ala-Pro-Pro-Ala-His-Gly-Val-Thr-S 
er-Ala), and derivatives of this sequence. Thus, different permutations of 
the 20 amino acid core sequence may be used, including substitutions, 
deletions, other permutations, and multiple repeats of any of the 
foregoing. For example, conserving the basic amino acid order and size of 
the peptide, the starting residue may be permuted. In one example, the 
repeat may begin with (SEQ ID NO: 4) GVTSA, instead of PDTRP, for example, 
yielding (SEQ ID NO: 6) GVTSAPDTRPAPGSTAPPAH. Other, similar permutations 
are also possible where the single repeat is linearly permuted by simply 
beginning with a different amino acid. 
Deletion derivatives of this core, including truncations and internal 
deletions, are especially useful. One particularly useful MUC-1 peptide 
derivative of this class is a 16 amino acid peptide of the sequence (SEQ 
ID NO: 7) GVTSAPDTRPAPGSTA. 
Some preferred peptide-based MUC-1 derivatives comprise one, or less than 
one, peptide core repeat of the MUC-1 mucin. Derivatives having less than 
one repeat generally contain at least 6 amino acids and even more 
preferably at least ten. This, of course, is subject to such a molecule 
having the requisite anergy/immunosuppression alleviating properties. The 
maximum size of "at most one MUC-1 core repeat" would be 20 amino acids, 
as prescribed by the native length. Hence the most preferred length is 
about ten to about twenty amino acids. 
Further MUC-1 derivatives include modified versions of a single MUC-1 core 
repeat. For example, given the basic repeat sequence, conservative 
substitutions may be made which preserve the requisite immunostimulatory 
characteristics. Such conservative substitutions include: charged amino 
acid for, preferably similarly, charged amino acid substitutions; polar 
for polar substitutions; and hydrophobic for hydrophobic substitutions. 
Substitutions may also rationally be made on the basis of physical 
characteristics such as size and ability to form or break helices. For 
example, proline and glycine may be substituted for one another based on 
their common helix-breaking properties. 
Other substitutions include replacing the L-amino acid with the 
corresponding D-amino acid. This rationale, moreover can be combined with 
the foregoing conservative substitution rationales. For example, D-serine 
may be substituted for L-threonine. In addition, peptides may be prepared 
which have an inverse sequence, relative to the native sequence. Hence, 
(SEQ ID NO: 2) DTRP becomes (SEQ ID NO: 5) PRTD. Such "retro-inverso" 
peptides are expected to have improved properties, such as increased in 
vivo half-life. This translates into smaller doses and more economically 
viable production. 
Other useful MUC-1 antagonists include glycosylated or non-glycosylated 
peptides. Glycosylation may improve circulating half-life and allow 
modulation of the immunosuppression-reversing characteristics of MUC-1 
derivatives. Glycosylation can be biological or non-biological. For 
example, biologically relevant N- or O-linked carbohydrates are 
envisioned. Other chemical modifications, such as succinylation are also 
contemplated. These specifically include modification with polyethylene 
glycols. 
MUC-1 antagonists also specifically include multiple repeats of any of the 
specific MUC- I derivatives defined herein. Moreover, each of the 
foregoing derivatives can be mixed and matched with each other. These 
multiple repeats are preferably tandem and usually will have a maximum of 
three repeated units. Thus, for example, a multiple repeat containing the 
full 20 amino acid core sequence would have a maximum length of 60 amino 
acids. However, the maximum number of repeated units ultimately will be 
determined by the derivative's immunostimulatory character. 
Although small peptides may be preferable from both economic and certain 
technical perspectives, larger molecules are also contemplated. Thus, 
MUC-1 antagonists may be combined with other useful therapeutic agents, 
yielding enhanced properties. They may be so combined, for example, 
covalently or electrostatically. Ideally these other therapeutic agents 
will be immunomodulators, and preferably will have immunostimulatory 
properties. Although non-protein agents are contemplated, the additional 
therapeutic agents are preferably proteins, which generically include 
peptides. Some particularly useful protein therapeutics include cytokines. 
In one example, fusion proteins comprise an inventive peptide fused to a 
cytokine. 
Such fusions are expected to have hybrid properties of reversing 
MUC-1-induced immunosuppression and more broadly inducing the immune 
response. Moreover, due to the interaction of the MUC-1-based peptide 
component with suppressed T-cells, the cytokine will be in a close 
physical proximity with the target cell, which may allow a specific 
cytokine-mediated induction of the very cells being de-repressed by the 
peptide portion of the MUC-1 derivative. Not only will immunosuppression 
be relieved, specific immunostimulation of the same T-cell population will 
be achieved. 
Particularly useful cytokines include those with immunostimulatory 
activity. Some preferred cytokines include the interleukins (ILs), and 
especially IL-2. Other useful cytokines include, for example, IL-1, IL-4, 
IL-7, IL-10, IL-12, and .gamma.-interferon. 
Specific useful MUC-1 antagonists can be derived from purified MUC-1, or 
portions thereof, produced by native sources or recombinant DNA 
methodology, by methods that include digestion with enzymes such as pepsin 
or papain. Alternatively, peptides encompassed by the present invention 
can be synthesized using an automated peptide synthesizer such as those 
supplied commercially by Applied Biosystems, Multiple Peptide Systems and 
others, or they may be produced manually, using techniques well known in 
the art. See Geysen et al., J. Immunol. Methods 102: 259 (1978). 
Glycosylated and other forms of peptide or protein MUC-1 derivatives may 
be made according to methods well known in the art. 
Although most preferred MUC-1 antagonists are protein- (or peptide-) based, 
other derivatives are contemplated. For example, small molecules which are 
amino acid or peptide mimetics may be useful. Rational design of such 
molecules is possible using methods known in the art. Using, for example, 
space-filling models, otherwise structurally unrelated compounds may be 
made to mimic protein-based MUC-1 derivatives. The usefulness of these 
MUC-1 derivatives can be confirmed using routine assays, such as those 
presented in Agrawal et al., Nature Medicine, 4:43 (1998). 
Further MUC-1 antagonists include normal ligands of MUC-1. Especially 
preferred among these ligands are cell adhesion molecules, such as 
intracellular adhesion molecule-1 (ICAM-1). In addition, these ligands may 
be shorter, for example proteolytically or recombinantly produced, 
truncated versions or fragments. They should, however, retain the ability 
to bind MUC-1. 
Still another important class of MUC-1 antagonists is antibody-based. 
Antibodies raised against the MUC-1 and its fragments are specifically 
contemplated. In order to act as antagonists of MUC-1 inhibitory function, 
antibodies should not induce crosslinking of MUC-1 and/or its cell surface 
receptor. Therefore, antibody antagonists of MUC-1 typically will be 
monovalent, such that each antibody can bind only a single MUC-1 molecule. 
MUC-1 antagonists are useful in methods for treating, preventing or 
substantially alleviating a variety of maladies, including 
cancer-associated immunosuppression, induction of anergy, viral diseases, 
and autoimmune diseases. 
Many viral diseases are known to promote some degree of immunosuppression 
which presumably affords them protection from immune clearance. For 
example, Epstein Barr Virus (EBV) induces expression of the lymphokine 
IL-10, which is known to down-regulate the T-cell response. Similarly, in 
some cases IL-4 may inhibit the TH1 response and thus shift the immune 
response to an antibody (humoral) response 
In addition, many cancers are known to mediate suppression of the T-cell 
response. For example, when tumors are isolated, specific T-cells called 
tumor infiltrating lymphocytes (TILs) are present. Although TILs are 
specific to the tumor from which they are isolated, they are anergic and 
thus do not respond to the tumor. This anergy may be reversed with 
interleukin-2 (IL-2) treatment. 
Similarly, tumors, such as adenocarcinomas, which secrete MUC-1 induce 
T-cell suppression or anergy. This effect is reversed by certain molecules 
which likely antagonize the binding of MUC-1 to its cognate cell surface 
receptor. Finally, many treatment protocols, for example, for cancer and 
antirejection are also immunosuppressive, and MUC-1 antagonists should be 
equally useful as an adjunct to those therapies. 
MUC-1 Enhancers 
Enhancers of MUC-1 function are also contemplated as a useful part of the 
invention. As explained, these molecules promote the T-cell 
down-regulatory aspects of MUC-1 function. In effect, they speed up the 
process of de-activating T-cells and, thus, they are immunosuppressive. 
MUC-1 enhancers generally Will induce crosslinking of MUC-1 molecules 
and/or MUC-1 receptors on the cell surface. Accordingly, they share the 
common characteristic of specifically binding MUC-1 and/or its receptor 
and they usually have multiple binding sites per molecule, in order to 
induce the crosslinking needed for immunosuppression. Due to these 
desirable characteristics, antibodies and their derivatives are preferred 
MUC-1 enhancers. Moreover, polyvalent versions, like hexavalent IgMs, are 
preferred because they should have a higher suppressive potential. On the 
other hand, where monovalent or bivalent molecules, like IgG and certain 
antibody derivatives, are employed, secondary antibodies may be necessary 
to induce sufficient crosslinking. Of course, secondary antibodies also 
may be used with higher-order molecules, but the are less likely to be 
needed in such a context. 
MUC-1 enhancers may be used to treat a variety of disorders characterized 
by over-active immune function, like autoimmune disorders and inflammatory 
disorders. MUC-1 enhancers may also be used to prevent or suppress organ 
transplantation rejection and graft versus host disease in bone marrow 
transplantation. They may also be used in conjunction with other known 
compounds that are useful for the same purposes. 
As used herein, an "inflammatory disorder" refers to any of the many 
inflammatory disorders that are well known to those of skill in the art. 
These disorders include, but are not limited to, the following disorders: 
inflammatory arthritis such as rheumatoid arthritis, psoriasis, allergies 
such as allergic contact dermatitis, and ankylosing spondylitis. 
As used herein, an "autoimmune disorder" refers to any of the many 
autoimmune disorders that are well known to those of skill in the art. 
These disorders include, but are not limited to, the following disorders: 
myasthenia gravis, systemic lupus erythematosus, polyarteritis nodosa, 
Goodpastures syndrome, isopathic thrombocytopenic purpura, autoimmune 
hemolytic anemia, Grave's disease, rheumatic fever, pernicious anemia, 
insulin-resistant diabetes mellitus, bullous pemphigold, pemphigus 
vulgaris, viral myocarditis (Cocksakie B virus response), autoimmune 
thyroiditis (Hashimoto's disease), male infertility (autoimmune), 
sarcoidosis, allergic encephalomyelitis, multiple sclerosis, Sjorgens 
disease, Reiter's disease, Celiac disease, sympathetic ophthalmia, and 
primary biliary cirrhosis. 
MUC-1-based Antibodies and Antibody Fragments 
Antibodies are useful in generating reagent for detection of activated 
T-cells and in producing either MUC-1 antagonists or MUC-1 enhancers. 
Antibodies include, but are not limited to polyclonal antibodies, 
monoclonal antibodies (mAbs), humanized or chimeric antibodies, single 
chain antibodies including single chain Fv (scFv) fragments, Fab 
fragments, F(ab').sub.2 fragments, fragments produced by a Fab expression 
library, anti-idiotypic (anti-Id) antibodies, epitope-binding fragments, 
and humanized forms of any of the above. 
In general, techniques for preparing polyclonal and monoclonal antibodies 
as well as hybridomas capable of producing the desired antibody are well 
known in the art (Campbell, A. M., Monoclonal Antibody Technology: 
Laboratory Techniques in Biochemistry and Molecular Biology, Elsevier 
Science Publishers, Amsterdam, The Netherlands (1984); St. Groth et al., 
J. Immnol. Methods 35:1-21 (1980); Kohler and Milstein, Nature 256:495-497 
(1975)), the trioma technique, the human B-cell hybridoma technique 
(Kozbor et al., Immunology Today 4:72 (1983); Cole et al., in Monoclonal 
Antibodies and Cancer Therapy, Alan R. Liss, Inc. (1985), pp. 77-96). 
Affinity of the antisera for the antigen may be determined by preparing 
competitive binding curves, as described, for example, by Fisher, Chap. 42 
in: Manual of clinical Immunology, second edition, Rose and Friedman, 
eds., Amer. Soc. For Microbiology, Washington, D.C. (1980). 
Fragments or derivatives of antibodies include any portion of the antibody 
which is capable of binding MUC-1. Antibody fragments specifically include 
F(ab').sub.2, Fab, Fab' and Fv fragments. These can be generated from any 
class of antibody, but typically are made from IgG or IgM. They may be 
made by conventional recombinant DNA techniques or, using the classical 
method, by proteolytic digestion with papain or pepsin. See CURRENT 
PROTOCOLS IN IMMUNOLOGY, chapter 2, Coligan et al., eds., (John Wiley & 
Sons 1991-92). 
F(ab').sub.2 fragments are typically about 110 kDa (IgG) or about 150 kDa 
(IgM) and contain two antigen-binding regions, joined at the hinge by 
disulfide bond(s). Virtually all, if not all, of the Fc is absent in these 
fragments. Fab' fragments are typically about 55 kDa (IgG) or about 75 kDa 
(IgM) and can be formed, for example, by reducing the disulfide bond(s) of 
an F(ab').sub.2 fragment. The resulting free sulfhydryl group(s) may be 
used to conveniently conjugate Fab' fragments to other molecules, such as 
detection reagents (e.g., enzymes). 
Fab fragments are monovalent and usually are about 50 kDa (from any 
source). Fab fragments include the light (L) and heavy (H) chain, variable 
(V.sub.L, and V.sub.H, respectively) and constant (C.sub.L C.sub.H, 
respectively) regions of the antigen-binding portion of the antibody. The 
H and L portions are linked by an intramolecular disulfide bridge. Because 
they are monovalent, and thus will not induce crosslinking, Fab fragments 
(like Fv, SCFv and other monovalent species) are particularly useful as 
antagonists of MUC-1 function. 
Fv fragments are typically about 25 kDa (regardless of source) and contain 
the variable regions of both the light and heavy chains (V.sub.L and 
V.sub.H, respectively). Usually, the V.sub.L and V.sub.H chains are held 
together only by non-covalent interacts and, thus, they readily 
dissociate. They do, however, have the advantage of small size and they 
retain the same binding properties of the larger Fab fragments. 
Accordingly, methods have been developed to crosslink the V.sub.L and 
V.sub.H chains, using, for example, glutaraldehyde (or other chemical 
crosslinkers), intermolecular disulfide bonds (by incorporation of 
cysteines) and peptide linkers. The resulting Fv is now a single chain 
(i.e., SCFv). 
Other antibody derivatives include single chain antibodies (U.S. Pat. No. 
4,946,778, Bird, Science 242:423-426 (1988); Huston et at., Proc. Natl. 
Acad. Sci. USA 85:5879-5883 (1988); and Ward et al, Nature 334:544-546 
(1989)). Single chain antibodies are formed by linking the heavy and light 
chain fragments of the Fv region via an amino acid bridge, resulting in a 
single chain FV (SCFv). 
Derivatives also include "chimeric antibodies" (Morrison et al., Proe. 
Natl. Acad. Sci., 81:6851-6855 (1984); Neuberger et al., Nature, 
312:604-608 (1984); Takeda et al, Nature, 314:452-454 (1985)). These 
chimeras are made by splicing the DNA encoding a mouse antibody molecule 
of appropriate specificity with, for instance, DNA encoding a human 
antibody molecule of appropriate specificity. Thus, a chimeric antibody is 
a molecule in which different portions are derived from different animal 
species, such as those having a variable region derived from a murine mAb 
and a human immunoglobulin constant region. These are also known sometimes 
as "humanized" antibodies and they offer the added advantage of at least 
partial shielding from the human immune system. They are, therefore, 
particularly useful in therapeutic in vivo applications. 
Pharmaceutical Compositions of the Invention 
The inventive compositions may be formulated for administration in a 
variety of ways. The pharmaceutical compositions of the invention 
generally contain a pharmaceutically effective amount of an inventive 
compound. Preferably, the compound is admixed with a pharmaceutically 
effective vehicle (excipient). 
A suitable formulation will depend on the nature of the specific medicament 
chosen, whether the treatment is in vivo or ex vivo, the route of 
administration desired and the judgement of the attending physician. 
Suitable formulations and pharmaceutically effective vehicles, can be 
found, for example, in REMINGTON'S PHARMACEUTICAL SCIENCES, chapters 
83-92, pages 1519-1714 (Mack Publishing Company 1990) (Remington's), which 
are hereby incorporated by reference. 
Preferred vehicles include liposomes. See, for example, Remington's at 
1691-92. Thus, the inventive compositions may also be formulated, and 
administered, in combination with other known medicaments, which may 
provide complementary anergy/immunosuppression relieving activity, in 
liposomal formulations. Preferred other medicaments include 
immunomodulators, such as the cytokines discussed above. 
The pharmaceutical compositions of the invention also may be formulated 
with stimulatory antigens, such as adjuvants. Such adjuvants are well 
known in the vaccine arts and typically function to enhance the immune 
response. Thus, preferred adjuvants useful in the invention are 
characterized by enhancing the ability of the inventive medicaments 
described herein to relieve antigen-induced immunosuppression/anergy. Some 
examples of well-known and useful adjuvants include those derived from 
bacterial lipopolysaccharides, such as lipid A, monophosphoryl lipid A. 
Therapeutic Methods of the Invention 
The inventive therapeutic methods generally utilize the MUC-1 modulators 
identified above. As indicated, the antagonists and the enhancers may be 
used to treat different disease states, depending upon the associated 
immune activation state. In general, methods entail modulating the immune 
either using an antagonist to stimulate it or using an enhancer to 
suppress it. 
Therapeutic methods involve administering to a subject in need of treatment 
a therapeutically effective amount of an inhibitor, as described above. 
Some methods also contemplate combination therapy. In the case where 
immunostimulation is desired, antagonists may be administered in 
conjunction with at least one other immunostimulatory medicament, and 
where immunosuppression is desired, enhancers may be administered with 
other immunosuppressants. The patient may be a human or non-human animal. 
A patient typically will be in need of treatment when suffering from a 
disorder associated with abnormal or undesirable immunosuppression or 
immune activation. 
The inventive methods may be employed in vivo or ex vivo. In a typical ex 
vivo method, for example, peripheral T-cells may be isolated from 
patients, treated with at least one MUC-1 modulator, alone or in 
combination, and reinfused into the patient. 
Administration during in vivo treatment may be by any number of routes, 
including parenteral and oral, but preferably parenteral. Specific 
preferred routes include direct injection of an antagonist into the tumor 
or the draining lymph nodes, in the case of a MUC-1-associated neoplasia. 
Thus, for example, the tumor infiltrating lymphocytes within the tumor, 
which are known to be immunosuppressed, will be specifically targeted and 
de-repressed. 
MUC-1 modulators may be administered alone, in combination with each other, 
or in combination with other medicaments. Ideally these other medicament 
agents will be immunomodulators, and have either immunostimulatory or 
immunosuppressive properties. Both protein and non-protein agents are 
contemplated. Some particularly useful protein-based immunostimulatory 
agents include stimulatory antigens and cytokines. Some preferred 
cytokines include the interleukins (ILs), and especially IL-2. Other 
useful stimulatory cytokines include, for example, IL1, L-4, IL-7, L-10, 
IL-12, andy-interferon. For example, cytokines may be coadministered, 
simultaneously or in succession, with MUC-1 antagonists. Of course, MUC-1 
inhibitors also may be used in combination with other immunostimulatory 
regimens. Immunosuppressive agents that may be coadministered with MUC-1 
modulators include steroid hormones, non-steroidal antiinflammatories, 
corticosteroids, and even cytoablative agents. 
Determining a pharmaceutically effective amount MUC-1 inhibitor is well 
within the purview of the skilled clinician, and largely will depend on 
the exact identity of the inhibitor, particular patient characteristics, 
route of administration and the nature of the disorder being treated. 
General guidance can be found, for example, in the publications of the 
International Conference on Harmonisation and in REMINGTON'S 
PHARMACEUTICAL SCIENCES, chapters 27 and 28, pp. 484-528 (Mack Publishing 
Company 1990). 
Determining a pharmaceutically effective amount specifically will depend on 
such factors as toxicity and efficacy of the medicament. Toxicity may be 
determined using methods well known in the art and found in the foregoing 
references. Efficacy may be determined utilizing the same guidance in 
conjunction with the methods described below in the Examples. A 
pharmaceutically effective amount, therefore, is an amount that is deemed 
by the clinician to be toxicologically tolerable, yet efficacious. 
Efficacy, for example, is measured by alleviation or substantial 
alleviation of anergy/immunosuppression or unwanted/illegitimate T-cell 
activation, in accord with the definition of "treating" discussed above. 
U.S. Provisional Application No. 60/090,916 is hereby incorporated by 
reference in its entirety. 
EXAMPLES 
Example 1 
Materials and Methods 
A. Antibodies/Reagents 
Mouse IgG, goat IgG and MOPC.21 (IgG1), were obtained from Sigma 
(Mississauga, Ontario, Canada). The cell culture media RPMI-1640, fetal 
bovine serum (FBS) and AIM V were obtained from Gibco BRL (Burlington, 
Ontario, Canada). Anti-CD3-FITC, anti-CD4-FITC/CD8-PE, IgG1-FITC/IgG1-PE, 
leukogate (CD45-FITC/CD14-PE), IgG1-FITC/IgG2-PE simultest control, 
anti-CD25-PE and anti-CD69-PE were purchased from Becton & Dickinson (San 
Jose, Calif., USA). Goat anti-mouse IgG1-PE, IgG1-FITC and isotype control 
mouse IgG1 were obtained from Southern Biotech (Birmingham, Ala., USA). 
Ficoll-Hypaque was obtained from Pharmacia Biotech (Baie d'Urfe, Quebec, 
Canada). Anti-CD3 (OKT3) was used as purified antibody obtained from 
culture supernatant of clones purchased from American Type Culture 
Collection (ATCC; Rockville, Md., USA). Anti-human- MUC-1 mAb B27.29 was 
purified from culture supernatant of the cell line B27.29 (Reddish et al., 
1992 J. Tumor Marker Oncol. 7:19). 
B. Cell Surface Immunofluorescence Staining 
Peripheral blood lymphocytes (PBLs) were isolated from buffy coats obtained 
from normal healthy donors (Canadian Red Cross, Edmonton, Alberta, 
Canada). For detection of cell surface antigens, PBLs cultured as 
indicated in each experiment were stained essentially as previously 
described (Agrawal e al., J. Immunol. 157:3229 (1996). Anti-MUC-1 mAb 
B27.29 (2 .mu.g/5.times.10.sup.5 T-cells) or isotype control antibody 
B80.3 (2 .mu.g/5.times.10.sup.5 T-cells) were used with indirect labelling 
with FITC or PE conjugated second antibody (G.alpha.M IgG1). In parallel, 
appropriate isotype control antibody was always used to stain the cells in 
a similar way. The isotype control groups had &lt;2% positive cells. The 
samples were analyzed by flow cytometry using FACSort.RTM. (Becton & 
Dickinson). Percent positive cells were defined as the fraction of cells 
exhibiting fluorescence intensities beyond a region set to exclude at 
least 98% of the control isotype matched antibody stained cells. 
C. Prolferation Assay 
PBLs were stimulated with PHA (1 .mu.g/ml) for 3 days, T-cells were then 
harvested and recultured in the presence or absence of OKT3, B27.29 mAb, 
isotype control mAb B80.3 and Goat anti-mouse in 96 well plates in 
quadruplicate. On the third day, the wells were pulsed with 1 uCi/well 
.sup.3 H Thymidine (Amersham). Incorporation of .sup.3 H Thymidine into 
DNA of proliferating T-cells was measured after harvesting the plates 
after 18-24 h and counting in liquid scintillation counter (Beckman LS 
60001C, Mississauga, ON, Canada). 
D. Determination of mRNA for Human MUC-1 by PCR 
MUC-1 mRNA in the lymphocytes was analyzed using reverse transcription PCR 
(RT-PCR). Total RNA was extracted from the T-cells using Trizol according 
to manufacturer's instructions (Life Technologies) and was reverse 
transcribed into cDNA with M-MLV Reverse Transcriptase and oligo d(T) 
(Perkin Elmer, Norwalk, Conn.). Subsequent DNA amplification was performed 
in the same tubes using AmpliTaq DNA polymerase (Perkin Elmer, Norwalk, 
Conn.) and MUC-1 specific primers (5'-TCTACTCTGGTGCACAACGG-3' (SEQ ID NO: 
10) and 5'-TTATATCGAGAGGCTGCTTCC-3' (SEQ ID NO: 11). These primers spanned 
a region within the genomic DNA that contained 2 introns and would result 
in the amplification of a 489 bp fragment from RNA and a 738 bp fragment 
from any contaminating genomic DNA. MCF-7 (human breast cancer cell line 
obtained from ATCC) RNA was used as a positive control and mouse spleen 
RNA was used as a negative control. RNA specific primers for human beta 
actin were used as a positive control with each RNA sample. Amplified 
fragments were run on a 2% agarose gel. All samples from lymphocytes that 
had been stimulated with PHA, produced a fragment of approximately 489 bp 
indicating the presence of human MUC-1 mRNA. Samples from unstimulated 
lymphocytes produced either no fragment or a faint product upon gel 
electrophoresis indicating no MUC-1 message or only a small amount. 
E. Determination of Soluble MUC-1 Mucin in Cell Supernatants 
MUC-1 in cell culture supernatants was determined with a sandwich enzyme 
immunoassay (EIA) employing mAb B27.29 (Biomira Inc.) as solid phase on 
polystyrene microwells (Nunc Maxisorp.TM.), horseradish peroxidase (HRP, 
Boehringer Mannheim), conjugated mAb B27.29 as tracer, and 
tetramethylbenzidine (TMB, Biomira Diagnostics Inc., Toronto, Ontario, 
Canada) as substrate. The HRP-B27.29 conjugate was prepared with the 
heterobifunctional cross-linker Sulfo-SMCC (Pierce). The EIA was 
calibrated by correlation with the TRUQUANT.RTM.BR.TM. RIA (Biomira 
Diagnostics Inc.). Cell culture supernatants were assayed undiluted; under 
these conditions the lower limit of detection is estimated to be in the 
range of 0.01-0.02 Units/ml. 
Example 2 
MUC-1 Mucin is Expressed on the Surface of Mitogen Activated Human T-cells 
PBLs obtained from buffy coats of normal Red Cross donors were stimulated 
with PHA for various time periods. Expression of MUC-1 mucin on the 
surface of PHA activated T-cells was examined by flow cytometry using 
anti-MUC-1 monoclonal antibody B27.29. MUC-1 mucin expression was examined 
at 1 day, 3 days and 6 days after in vivo culture initiation with or 
without PHA stimulation. FIG. 1, presents the time course of MUC-1 
expression on activated human T-cells. At each time point, cells were 
collected and stained for CD3 and MUC-1 expression. The top (A) row 
represents cells in the absence of mitogen stimulus and the bottom (B) row 
represents cells cultured in the presence of PHA. As controls isotype 
matched antibody was used (data not shown), that stained &lt;2% of the cells. 
The number in parentheses represents percent MUC-1 positive T-cells. 
FIG. 1 demonstrates that in cultures without added PHA there was a low 
(1-4%) number of MUC-1 positive cells in the CD3.sup.+ T-cell population. 
In PHA stimulated cultures there was an increase in the number of 
B27.29.sup.+ CD3.sup.+ cells to a peak of approximately 80% positive 
cells 3 to 6 days post culture initiation. As a control for mAb B27.29 
binding specificity, we determined whether the presence of soluble MUC-1 
mucin inhibits mAb B27.29 binding to 3 day PHA activated T-cells. We 
observed a MUC-1 mucin dose dependent inhibition of staining of activated 
human T-cells with B27.29: at 1 .mu.g of MUC-1 mucin, a 25% inhibition of 
binding was noted, at 10 .mu.g MUC-1 a 45% inhibition and at 50 .mu.g 
MUC-1 a 65% inhibition of B27.29 binding to activated T-cells was noted. A 
negative control mucin (OSM) did not inhibit binding of B27.29 to PHA 
activated T-cells (0% inhibition of binding of mAb B27.29 at 50 .mu.g 
OSM). 
Example 3 
mRNA for MUC-1 Mucin is Present in Activated T-cells 
In order to confirm that the appearance of cell surface MUC-1 on activated 
T-cells represents the presence of newly synthesized mucin, RT-PCR was 
performed in a time course experiment where the expression of MUC-1 on the 
cell surface was determined at the same time as MUC-1 mRNA determination. 
Both MUC-1 mRNA and surface expression were determined in T-cells cultured 
in the presence or absence of PHA after 1 day, 3 day and 6 days after 
culture. Gel electrophoresis demonstrated that MUC-1 specific mRNA could 
be detected by RT-PCR after 24 h of PHA stimulation with increased 
expression noted at days 3 and 6. MUC-1 mRNA was present in PHA stimulated 
cells but not in the unstimulated cells and correlated with surface 
expression of MUC-1 (see FIG. 1). 
Example 4 
MUC-1 Mucin is Expressed by both CD4 and CD8 Positive T-cells 
Double staining with anti-CD4 or anti-CD8 mAbs and mAb B27.29 demonstrates 
that at days 5 and 7 after activation of PBLs with PHA, approximately 80% 
of the CD4.sup.+ T-cells are MUC-1 positive and approximately 65% of the 
CD8.sup.+ T-cells are MUC-1 positive (Table I). 
TABLE I 
______________________________________ 
MUC-1 is expressed on both CD4.sup.+ and CD8.sup.+ T-cells 
Time after PHA % of CD4.sup.+ T-cells 
% of CD8.sup.+ T-cells 
Stimulation positive for MUC-1 positive for MUC-1 
______________________________________ 
5 days 86.6% 69.6% 
7 days 80.7% 66.5% 
______________________________________ 
Example 5 
MUC-1 Mucin is Co-expressed with other T-cell Activation Markers 
Double staining for MUC-1 mucin expression with anti-CD25 or anti-CD69 mAbs 
was carried out on days 1, 3, 6 following T-cell activation with PHA. 
Table II demonstrates that the percentage of cells co-expressing CD69 or 
CD25 and MUC-1 mucin increased with time in culture. However, the kinetics 
of CD69 or CD25 expression seems to be different than that of MUC-1 
expression because at day 1 after stimulation approximately 18% of the 
CD25.sup.+ T-cells are MUC-1 positive and 15% of the CD69.sup.+ T-cells 
are MUC-1 positive; at day 3 after stimulation approximately 74% of the 
CD25.sup.+ T-cells are MUC-1 positive and 75% of the CD69.sup.+ T-cells 
are positive; finally, at day 6 after stimulation approximately 80% of 
both CD25.sup.+ and CD69.sup.+ T-cells are MUC-1 positive. 
TABLE II 
______________________________________ 
MUC-1 coexpressed with other T-cell activation markers 
Time after PHA 
% of CD69.sup.+ T-cells 
% of CD25.sup.+ T-cells 
stimulation positive for MUC-1 positive for MUC-1 
______________________________________ 
1 h 9.1 ND 
4 h 8.1 ND 
1 day 14.75% 17.4% 
3 days 75.5% 74.3% 
6 days 81.6% 80.2% 
______________________________________ 
Example 6 
Down regulation of MUC-1 Expression on Activated T-cells Following Removal 
of the Mitogen 
T-cells were cultured in the presence of PHA for 1, 3 and 6 days, followed 
by washing and reculturing in media without PHA for an additional 3 and 6 
days. FIG. 3 shows that expression of MUC-1 mucin on T-cells is 
reversible. (n) PBLs were cultured in the presence of PHA for 1, 3 and 6 
days. At day 6, the cells were washed, harvested and recultured in the 
absence of PHA (media alone) for further 3-6 days. (l) PBLs were cultured 
in the absence of PHA for 6 days after which PHA was added and cells were 
cultured again for a further 6 days. In both groups, cells were harvested 
at each time point 1, 3, 6, 9 and 12 days and double stained for CD3 and 
MUC-1 (B27.29 mAb) expression. Data is shown as the mean percent of MUC-1 
positive T-cells.+-.S.D. 
As shown in FIG. 3, after removing the PHA from the cultures, MUC-1 
expression was reduced with time. This reduction in MUC-1 expression is 
analogous to transient expression of T-cell activation marker CD69 (Testi 
et al., J. Immunol. 142: 1854-1860 (1989)). It was found that surface CD69 
expression reaches to peak level by 18-24 h after stimulation and declines 
with the removal of stimuli. In addition, T-cells cultured in the absence 
of PHA for 1, 3 and 6 days and then stimulated with PHA, MUC-1 on T-cells 
expression was not observed up to 6 days in culture without PHA but MUC-1 
expression is apparent after subsequent. 
Example 7 
Soluble MUC-1 Mucin is Found in Cell Supernatants of Activated Human T-cell 
cultures 
An enzyme-linked immunoassay (EIA) specific for MUC-1 mucin was used to 
test supernatants from PHA activated T-cells for the presence of soluble 
MUC-1 mucin. Table III shows that supernatants from PHA activated but not 
non-activated cultures contained increasing amount of soluble MUC-1 mucin 
with a peak level of approximately 27 U/ml culture supernatant at day 6. 
TABLE III 
______________________________________ 
Activated human T-cells secrete or shed detectable amounts of MUC-1 
into culture supernatants 
Amount of secreted MUC-1 (U/mlX10.sup.2) mean .+-. S.D. 
Time in Culture 
PBLs without PHA 
PBLs with PHA (1 ug/ml) 
______________________________________ 
1 day 2.0 .+-. 0.1 1.5 .+-. 0.2 
3 days 1.6 .+-. 0.1 12.9 .+-. 1.0 
6 days 1.3 .+-. 0.0 27.2 .+-. 3.6 
7 days 1.7 .+-. 0.1 24.2 .+-. 0.1 
______________________________________ 
Example 8 
Cross-linking Surface MUC-1 Mucin by Antibody Inhibits the T-cell 
Proliferative Response 
Human PBLs were stimulated with PHA for 3 days to induce the expression of 
MUC-1 mucin. At this time the cells were harvested, washed, and recultured 
in the presence of anti-CD3 (OKT3, as polyclonal stimuli), with or without 
anti-MUC-1 mAb B27.29 and Goat-anti-mouse antibody. It appears that the 
T-cells stimulated in the presence of MUC-1 cross-linking conditions, the 
proliferation response was lower than that of the cells cultured in the 
presence of isotype control antibody. This experiment is illustrated in 
FIG. 4. There, human PBLs were cultured in the presence of PHA for 3 days. 
At this time, cells were harvested and set up in 96 well flat bottom plate 
at 1.times.10.sup.5 cells/well in the presence or absence of media, OKT3 
(.alpha.CD3 as stimulant), .alpha.MUC-1 (B27.29 mAb) and Goat-anti-mouse 
antibody. On the third day of culture, .sup.3 H-Tdr was added and 
proliferation was measured on the fourth day. The data represent mean 
CPM.+-.S.D. of four replicate wells. 
Example 9 
Cross-linking Surface MUC-1 Mucin by Antibody Represses T-cell 
Proliferative Response 
This example shows that cross-linking of MUC-1 (and, thus, likely its cell 
surface receptor) is the triggering event for T-cell down-regulation. 
These data show that when a bivalent IgG anti-MUC-1 molecule is used, a 
secondary antibody is required to induce substantial suppression. On the 
other hand, when a hexavalent IgM antibody is used, effective 
down-regulation is observed without a secondary antibody. 
Experiments were performed essentially as describe in Example 8. Briefly, 
2.times.10.sup.5 human peripheral T lymphocytes/ well were stimulated with 
anti-CD3 (OKT3, polyclonal stimulus) in the presence of anti-MUC-1 
antibody (B27.29) or the appropriate isotype control or with other 
antibodies along with second cross-linking goat-anti-mouse antibody for 3 
days in a 96-well microtitre flat well plate. After this time, the wells 
were pulsed with .sup.3 H-Tdr overnight and the cells were harvested. 
Incorporation of .sup.3 H-Tdr in the DNA of proliferating T-cells was 
determined by liquid scintillation counting. The results are shown as 
percent inhibition of proliferation as calculated by: 
##EQU1## 
Data are shown in Table IV. 
TABLE IV 
______________________________________ 
Anti-MUC1 antibodies reactive against carbohydrate, tandem repeat 
peptide core or non-VNTR region, bind to activated human T-cells 
and induce an inhibition of proliferation. 
Effect on 
Binding T-cell proliferation 
to activated (% Inhibition) 
T-cells (% 25 
Antibody* Epitope Positive cells) 5 .mu.g/ml** .mu.g/ml** 
______________________________________ 
B27.29 Glycopeptide 
60-80 58 82 
(VNTR) 
SM3 APDTRP 54 26 96 
(SEQ ID NO:8) 
(VNTR) 
BC4E549 TSAPDTRPAP 62 17 49 
(SEQ ID NO:9) 
(VNTR) 
M29 Non-VNTR 28 24 48 
peptide core 
DH-1 Le.sup.X 49 9 59 
M26 SLe.sup.X 39 4 54 
______________________________________ 
*Isotype matched control antibodies did not bind to activated Tcells or 
have an effect on Tcell proliferation. 
**Antibody concentration in culture. 
The foregoing detailed discussion and working examples are presented merely 
for illustrative purposes and are not meant to be limiting. Thus, one 
skilled in the art will readily recognize additional embodiments within 
the scope of the invention that are not specifically exemplified. 
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# SEQUENCE LISTING 
- - - - &lt;160&gt; NUMBER OF SEQ ID NOS: 11 
- - &lt;210&gt; SEQ ID NO 1 
&lt;211&gt; LENGTH: 20 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 1 
- - Pro Asp Thr Arg Pro Ala Pro Gly Ser Thr Al - #a Pro Pro Ala His 
Gly 
1 5 - # 10 - # 15 
- - Val Thr Ser Ala 
20 
- - - - &lt;210&gt; SEQ ID NO 2 
&lt;211&gt; LENGTH: 4 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 2 
- - Asp Thr Arg Pro 
1 
- - - - &lt;210&gt; SEQ ID NO 3 
&lt;211&gt; LENGTH: 7 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 3 
- - Ser Ala Pro Asp Thr Arg Pro 
1 5 
- - - - &lt;210&gt; SEQ ID NO 4 
&lt;211&gt; LENGTH: 5 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 4 
- - Gly Val Thr Ser Ala 
1 5 
- - - - &lt;210&gt; SEQ ID NO 5 
&lt;211&gt; LENGTH: 4 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 5 
- - Pro Arg Thr Asp 
1 
- - - - &lt;210&gt; SEQ ID NO 6 
&lt;211&gt; LENGTH: 20 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 6 
- - Gly Val Thr Ser Ala Pro Asp Thr Arg Pro Al - #a Pro Gly Ser Thr Ala 
1 5 - # 10 - # 15 
- - Pro Pro Ala His 
20 
- - - - &lt;210&gt; SEQ ID NO 7 
&lt;211&gt; LENGTH: 16 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 7 
- - Gly Val Thr Ser Ala Pro Asp Thr Arg Pro Al - #a Pro Gly Ser Thr Ala 
1 5 - # 10 - # 15 
- - - - &lt;210&gt; SEQ ID NO 8 
&lt;211&gt; LENGTH: 6 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 8 
- - Ala Pro Asp Thr Arg Pro 
1 5 
- - - - &lt;210&gt; SEQ ID NO 9 
&lt;211&gt; LENGTH: 10 
&lt;212&gt; TYPE: PRT 
&lt;213&gt; ORGANISM: Homo sapiens 
- - &lt;400&gt; SEQUENCE: 9 
- - Thr Ser Ala Pro Asp Thr Arg Pro Ala Pro 
1 5 - # 10 
- - - - &lt;210&gt; SEQ ID NO 10 
&lt;211&gt; LENGTH: 20 
&lt;212&gt; TYPE: DNA 
&lt;213&gt; ORGANISM: Artificial Sequence 
&lt;220&gt; FEATURE: 
&lt;223&gt; OTHER INFORMATION: Description of Artificial - #Sequence: Primer 
- - &lt;400&gt; SEQUENCE: 10 
- - tctactctgg tgcacaacgg - # - # 
- # 20 
- - - - &lt;210&gt; SEQ ID NO 11 
&lt;211&gt; LENGTH: 21 
&lt;212&gt; TYPE: DNA 
&lt;213&gt; ORGANISM: Artificial Sequence 
&lt;220&gt; FEATURE: 
&lt;223&gt; OTHER INFORMATION: Description of Artificial - #Sequence: Primer 
- - &lt;400&gt; SEQUENCE: 11 
- - ttatatcgag aggctgcttc c - # - # 
- #21 
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