bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tissue distribution and ontogenetic emergence of differentiation antigens on avian T cells
Authors: Peault Bruno , Coltey Monique , Douarin Nicole M. Le 
Published: February 2007

AbstractTwo distinct antibodies raised against quail thymocytes were used in an indirect immunofluorescence assay to analyze the expression of differentiation antigens on T lineage cells in embryonic and newly hatched quail, (a) A rabbit serum, anti‐AT‐65, that has been previously shown to immunoprecipitate a protein of apparently 65‐70 kDa from quail and chick thymocytes, reacts with both thymic and peripheral T cells. The polyspecificity of this pan‐avian T cell reagent can be dissected by absorption and includes reactivities against two distinct antigenic entities. One of these is restricted to thymocytes whereas the other is also expressed on peripheral T cells, (b) A monoclonal antibody, a‐TD1, defines the population of cortical thymocytes and does not react with peripheral T cells. Binding assays during the embryonic development of the T lineage reveal that specific surface markers are expressed 36 h following the seeding of lymphoid precursor cells to the thymic rudiment, suggesting their early commitment in this lymphoid microenvironment. T cells are also shown to be exported precociously to the embryonic splenic compartment.
The distribution, ontogeny and origin in the rat of Ia‐positive cells with dendritic morphology and of Ia antigen in epithelia, with special reference to the intestine
Authors: Mayrhofer Graham , Pugh Christopher W. , Barclay A. Neil 
Published: February 2007

AbstractIa antigens were localized in cryostat sections of rat intestine and other tissues by an indirect immunoperoxidase technique using monoclonal antibodies that recognize the rat antigens homologous to the gene products of the I‐A and I‐E subregions of the mouse major histocompatibility complex (MHC). Two categories of Ia+ cells were characterized, namely epithelial cells and bone marrow‐derived cells with dendritic morphology. In the small intestine Ia antigen was present in the distal 2/3 of the absorptive epithelium but absent from the bases of the villi, the crypts and the epithelium covering the Peyer's patches. The distribution in nude rats was similar, indicating that T lymphocytes are not obligatory for its expression. In ontogeny Ia antigen was absent in the epithelium of neonatal gut, appearing at about 4 weeks of age and reaching adult levels at about 6 weeks. Different rat strains showed large differences in the amount of Ia antigen expressed by villus epithelium and the traits for the level of expression were shown to map outside the MHC. The levels of expression of Ia antigen in the proximal tubules of the kidney followed that of the gut epithelium in the different strains and in both tissues was mostly intracellular. Studies with chimeras showed that the Ia antigen in epithelial cells was not acquired from bone marrow‐derived cells.The second category of cell studied had a characteristic dendritic morphology and was present in large numbers in the lamina propria of the villi and in the crypts. In the Peyer's patches these cells were present both in the subepithelial dome region and within the epithelium itself. These Ia+ dendritic cells were present in nude rat jejunum and appeared in normal fetal gut by 18 days gestation and were also shown to migrate into antigen‐free grafts of fetal gut. This suggests that they do not require stimulation from antigens, bacterial products or T lymphocytes in order to localize in the gut or to express Ia antigen. Studies with other cell surface markers suggest that the Ia+ cells with dendritic morphology represent a range of cell types, some with similarities to macrophages and others to nonphagocytic dendritic cells.
Distinct helper activities control growth or maturation of B lymphocytes
Authors: Pettersson Sven , Pobor Grgur , Bandeira Antonio , Coutinho Antonio 
Published: February 2007

AbstractA clone (C‐11) of C3H/HeJ Lyt‐1+2− T cells with specificity for “minor” antigens of C3H/Tif has been isolated which, in contrast to other similarly derived clones, did not activate polyclonal plaque‐forming cell (PFC) responses in T cell‐depleted “target” spleen cells. This clone, however, showed unaltered proliferative responses to the naturally occurring antigen(s) on presenting cells, and strongly synergized with regular helper clones in the induction of PFC responses. Further analysis demonstrated that C‐11 cells are competent to stimulate extensive “target” B cell proliferation, but lack the ability to produce (or participate in the production of) maturation factors for activated B cells. Thus, the defective PFC responses could be fully reconstituted with supernatants from regular clones stimulated with antigen, but not by supernatants prepared from the C‐11 cells themselves.While it is not clear whether this clone represents a normal helper T cell subpopulation or a variant that has lost maturation‐factor production, these results demonstrate that distinct factors control growth and maturation in T cell‐dependent B lymphocyte responses.
Normal human B cells express endogenous sheep erythrocyte (E) receptor after appropriate in vitro culture
Authors: Mills Kingston H. G. , Worman Colin P. , Cawley John C. 
Published: February 2007

AbstractWhen normal human B cells from blood, tonsil or spleen are cultured with 20–30% autologous or allogeneic T cells and mitogen, the majority of cells rosette with sheep erythrocytes (E) after 3–5 days in culture. These E+ cells are of transformed appearance and several points indicate that many are derived from B cells. Some simultaneously possess surface immunoglobulin (sIg) or a B cell antigen [detected with BA1 monoclonal antibody (mAb)] and E receptor. Many do not stain with anti‐T cell mAb (UCHT1, OKT4, OKT8), while cultured T cells continue to express these antigens. Furthermore, many E+ cells appear when the original T cells have been irradiated. All the cultured E+ cells stain with OKT11, an mAb against the E receptor, and their positivity cannot therefore be attributed to mitogen‐induced nonspecific stickiness. The E positivity of the B cells was shown to be endogenous since passive acquisition of E receptor shed by T cells was excluded in a number of ways; no phenotypic changes were observed when supernatants from cultures containing many E+ sIg+ non‐T cells were added to B cells, or when the B and T cells were separated by a Millipore membrane; and E receptor was re‐expressed after stripping with trypsin or pronase. The intimate presence of T cells is essential for the expression of E receptors by B cells, and this helper capacity was shown to reside within the OKT4‐defined helper T cell subpopulation. The significance of the expression of E receptor by B cells is discussed in relation to the recent in vitro and in vivo demonstration of E+ sIg+ cells in certain leukemias and in relation to the specificity of E rosetting as a marker of T cells.
In vitro propagation of cultured human natural killer cells expressing the HNK‐1 differentiation antigen and spontaneous cytotoxic function
Authors: Abo Toru , Balch Charles M. 
Published: February 2007

AbstractHuman natural killer (NK) cells expressing the HNK‐1 differentiation antigen were established in long‐term tissue culture for over 3 months. The fluorescence‐activated cell sorter‐purified HNK‐1+ cells required both phytohemagglutinin and exogenous interleukin 2 to propagate in long‐term culture. After 2 weeks of culture, virtually all of the growing cells exhibited the surface membrane phenotype associated with immature HNK‐1+ cells, since they simultaneously expressed the HNK‐1, Leu‐4 and Leu‐2a but lacked the M1, Leu‐3a and T6 antigens, and Fcγ receptors. They exhibited a lymphoblastoid appearance, contained cytoplasmic granules, and exhibited spontaneous cytotoxic function against a broader spectrum of target cells than did fresh HNK‐1+ cells from the same donor. Cultured HNK‐1+ cells lacked antibody‐dependent cell‐mediated cytotoxic (ADCC) function, while fresh HNK‐1+ were fully capable of ADCC function. On the other hand, cultured HNK‐1− cells were lymphoblasts without cytoplasmic granules or NK cytotoxic function. The cultured HNK‐1+ cells gradually lost their HNK‐1 antigen expression over time, although the expression of other surface antigens (e.g., Leu‐4 and Leu‐2a) was unchanged. With prolonged culture (> 2 months), they also exhibited decreasing cytotoxic function and a diminished number of cytoplasmic granules. They were eventually indistinguishable from HNK‐1− cells after 3 months of culture. These observations were not influenced by adding interferon‐γ to the cultures. The results demonstrate that the immature form of NK cells (that express T cell antigens) preferentially proliferate in long‐term cultures when incubated with phytohemagglutinin and interleukin 2.
In vitro correction of the interleukin 2 defect of autoimmune mice
Authors: Santoro Thomas J. , Luger Thomas A. , Ravache Elizabeth S. , Smolen Josef S. , Oppenheim Joost J. , Steinberg Alfred D. 
Published: February 2007

AbstractThe effect of concanavalin A (Con A) and/or phorbol myristate acetate (PMA) on interleukin 2 (IL2) production and tritiated thymidine incorporation was measured in young (6 weeks) and old (16‐24 weeks) autoimmune mice by pulsing 5 × 106 unfractionated spleen cells with 5 μg of Con A and/or 5 ng of PMA for variable periods of time. The apparent deficiency in Con A‐stimulated IL2 production manifested by mice prone to the development of autoimmune disease was repaired by the addition of PMA. PMA did not enhance interleukin 1 (IL 1) secretion in autoimmune MRL‐lpr mice either alone or in combination with Con A. The addition of purified IL 1 to Con A‐pulsed autoimmune cells did not increase IL2 production. Freeze‐thaw experiments suggested that PMA does not promote IL2 synthesis. Con A‐pulsed cells plus PMA‐pulsed cells do not syngergize. These data indicate that autoimmune‐prone mice are capable of producing IL 2 and of proliferating in response to Con A provided the comitogen PMA is present. It can be argued that the failure to produce IL2 or to respond to proliferative signals is not fundamental to the development of the disease sustained by autoimmune‐prone mice.
Haplotype‐specific suppressor T cells mediating linked suppression of immune responses elicited by third‐party H‐2 alloantigens
Authors: Holáň Vladimír , Mitchison N. Avrion 
Published: February 2007

AbstractSpecific suppressor T cells (Ts) were induced in vitro by incubation of mouse spleen/lymph node cells with allogeneic heat‐treated cells. These Ts inhibit mixed lymphocyte reaction (MLR) in a haplotype‐specific manner. Ts also suppress cell proliferation induced by third‐party H‐2 alloantigens provided these are expressed on the same cell surface as at least some of the H‐2 antigens used for Ts activation. Ts activated by H‐2 plus non‐H‐2 alloantigens suppress an MLR induced by irrelevant H‐2 alloantigens if these are expressed on the same cell surface as the non‐H‐2 alloantigens used for Ts activation. Products of the H‐2 region or non‐H‐2 alloantigens which are not able to stimulate cell proliferation do not activate Ts. These Ts are first demonstrable after 4 days of incubation of lymphoid cells with heat‐treated allogeneic cells and they inhibit MLR only if added at the very beginning of the culture. Exogenous interleukin 2 does not overcome suppression and the suppression is not due to a cytotoxic effect, since heat‐treated cells do not elicit cell proliferation or cytotoxic cells. Moreover, the specific Ts differ in their Thy‐1+,Ly‐1+,2− phenotype from Ly‐2+ allospecific cytotoxic cells. Thus specific Ts could be induced in vitro, which demonstrate linked suppression for third‐party H‐2 alloantigens provided these are expressed on the same cell surface as the antigens used for Ts activation.
Accessory functions and mutual cooperation of murine macrophages and dendritic cells
Authors: Miyazaki Hiroshi , Osawa Toshiaki 
Published: February 2007

AbstractIn this study the antigen‐presenting functions of murine splenic dendritic cells (DC) and macrophages (MΦ) have been compared. DC and MΦ were pulsed with keyhole limpet hemocyanin (KLH) and found to contain approximately 92% and 50% Ia‐positive cells, respectively. The two KLH‐pulsed cell populations had almost equal ability to stimulate KLH‐immune T cells. The antigen‐presenting functions of DC and MΦ were compared by measuring the capacity of KLH‐pulsed, UV‐irradiated cells, which failed to secrete interleukin 1 (IL1), to stimulate KLH‐immune T cells when each culture was supplemented with an equal amount of exogenous IL1. The antigen‐presenting capacity of DC was always greater than that of MΦ. Coculturing of the two kinds of accessory cells upon KLH pulsing resulted in enhanced antigen‐presenting capacity of the mixture relative to the same number of each accessory cell type. That is, collaboration between them in antigen presentation was clearly observed. However, direct contact between DC and MΦ was not obligatory for this collaboration. Furthermore, we found that different types of soluble factors released by each of them might be responsible for the collaboration. In addition, supernatants of concanavalin A‐stimulated spleen cells augmented the antigen‐presenting function of only MΦ. Finally, the antigen‐presenting function of DC and MΦ from athymic mice was almost the same as that from control mice.
Heterogeneous and monoclonal helper T cells induce similar anti‐(4‐hydroxy‐3‐nitrophenyl)acetyl (NP) antibody populations in the primary adoptive response II. Lambda light chain dominance and idiotope expression
Authors: Smith Frances I. , Tesch Hans , Rajewsky Klaus 
Published: February 2007

AbstractWhen the hapten (4‐hydroxy‐3‐nitrophenyl)acetyl (NP) is presented on different carrier molecules, different anti‐NP antibody responses are stimulated. On stimulation with NP‐lipopolysaccharide (LPS) [T‐independent type 1 (TI‐1) antigen] kappa (x)+ antibodies are the major population, whereas on stimulation with NP‐Ficoll [T‐independent type 2 (TI‐2) antigen], NP‐keyhole limpet hemocyanin (KLH) or NP‐chicken gamma globulin (CG) [T‐dependent (TD) antigens], lambda (λ) 1+ antibodies dominate. The relative contribution of idiotopes Ac38 or Ac146 to the λ1+ anti‐NP response was also different on comparison of TI‐1 with TI‐2 or TD anti‐NP responses. We investigated whether light chain‐ or idiotype‐specific T cells are responsible for these differences. Analysis of the anti‐NP response of nude mice after immunization with NP‐Ficoll showed λ1 dominance. Likewise primary adoptive transfer experiments using carrier‐specific T cell lines to reconstitute the TD anti‐NP response to NP‐KLH or NP‐CG, showed that help from carrier‐specific T cells alone is capable of stimulating the characteristic λ1 dominant response. No significant difference could be found in the levels of Ac38 and Ac146 idiotope expression between mice reconstituted with splenic T cells and those reconstituted with T cell lines. These results suggest that light chain‐ or idiotype‐specific T cells are required neither for the production of λ1 light chain dominance, nor for the appearance of idiotopes characteristic of the primary anti‐NP response. The possible reasons for differences seen in both light chain and idiotope expression between primary anti‐NP responses to the TI‐1 antigen NP‐LPS and those to TD or TI‐2 antigens are discussed.
Cross‐protection in mice infected with influenza A virus by the respiratory route is correlated with local IgA antibody rather than serum antibody or cytotoxic T cell reactivity
Authors: Liew Foo Y. , Russell Stuart M. , Appleyard Geoffrey , Brand Colin M. , Beale John 
Published: February 2007

AbstractMice previously infected with an aerosol of A/Rec 31 influenza virus were strongly protected against an aerosol challenge with A/Vic influenza as judged by lung virus titers recovered 2 days after the challenge infection. Such complete homotypic immunity was not achieved by priming with live Rec 31 virus injected i.v. or UV‐inactivated Rec 31 virus administered s.c. together with Al(OH)3 and saponin. The reason for the superior protective effect of the natural infection was investigated. The protection induced by respiratory infection with Rec 31 virus was specific for influenza A viruses. It was not correlated with specific serum hemagglutination inhibition antibody titer or cross‐reactive cytotoxic T (Tc) cell reactivity. Moreover, the transfer of splenic and lymphoid T cell populations with strong secondary Tc activity did not significantly reduce lung virus titers in recipient mice 3 days after infection. The protection however occurred in parallel with the presence of cross‐reactive IgA antibody in the lung washings. It thus appears that local secretory IgA plays a causal role in the prevention of cross‐infection by influenza A virus. Serum antibody and Tc cells, on the other hand, may be crucial for recovery from such infection. All mice primed with live Rec 31 virus, administered i.v. or by aerosol and expressing equally high levels of Tc reactivity, survived a lethal challenge with A/PR8 virus. The same challenge, however, killed half of the mice immunized s.c. with inactivated Rec 31 virus which induced only a low level of Tc reactivity.
Autoregulation of autoantibody synthesis in mercuric chloride nephritis in the Brown Norway rat I. A role for T suppressor cells
Authors: Bowman Christine , Mason Donald W. , Pusey Charles D. , Lockwood Christopher M. 
Published: February 2007

AbstractMercuric chloride injections in the Brown Norway rat induce the transient formation of anti‐glomerular basement membrane (GBM) autoantibodies. Transfer of spleen cells from convalescent animals, after circulating anti‐GBM autoantibodies are no longer detectable, inhibits reinduction of the disease by HgCl2 in naive recipients. This inhibition is significantly less when the T suppressor cell population is depleted by the monoclonal antibody, MRCOX8, before transfer. Our studies suggest a role for T suppressor cells in autoregulation in this animal model of autoimmune nephritis and may form a basis for the design of specific therapy for anti‐GBM disease in man.
Frequency of λ light chain subtypes in mouse antibodies to the 2,4‐dinitrophenyl (DNP) group
Authors: Liu Theresa , Reilly Edward B. , Chengbo Zhang , Eisen Herman N. 
Published: February 2007

AbstractOf the three λ chain subtypes made by inbred mice, chains of the λ1 subtype are much more frequent than those of the other subtypes (λ2,λ3) in antibodies (Ab) to those few antigenic structures that are known to elicit responses, in which λ chains are the predominant type of light chain [(4‐hydroxy‐3‐nitrophenyl)acetyl (NP) and dextran]. The reasons for the frequency differences are not understood, and the large difference between the λ1 and λ3 frequencies is particularly puzzling, because in nearly all (about 95%) chains of these subtypes the N‐terminal 97 or 98 amino acids are endoded by the same Vλ‐gene segment. In an effort to identify an Ab response that has different λ subtype frequencies, we analyzed the light chains of the Ab made by BALB/c and B6 mice in response to 2,4‐dinitrophenylated chicken gamma globulin (DNP‐CGG). We found that approximately 40% of the elicited anti‐DNP molecules had λ chains and of these approximately 40% were of the λ2 or λ3 subtype. Polyacrylamide gel electrophoresis indicated that the λ2 and λ3 chains were about equally abundant. Similar λ subtype frequencies were found in the anti‐DNP Ab produced by the hybridomas made with spleen cells from the same immunized mice. In the anti‐DNP Ab elicited by DNP‐CGG and in the anti‐NP Ab elicited by NP‐CGG the different λ subtype frequencies (λ1/λ2 + λ3 = ca. 1.0‐1.5 in anti‐DNP and ca. 30 in anti‐NP) were unaffected by immunizing mice with each of these antigens alone or with a mixture of the two. This finding, though preliminary, suggests that isotype‐specific regulatory T cells are not responsible for the markedly different λ subtype frequencies in anti‐DNP and anti‐NP Ab.
Isotypes and specificities of immunoglobulins produced by germ‐free mice fed chemically defined ultrafiltered “antigen‐free” diet
Authors: Hooijkaas Herbert , Benner Robbert , Pleasants Julian R. , Wostmann Bernard S. 
Published: February 2007

AbstractThe regulation of the “spontaneously” occurring (“background”) Ig synthesis of mice has been studied by determining the numbers of IgM‐, IgG‐ and IgA‐secreting cells and a part of the IgM antibody‐specificity repertoire in spleen, bone marrow (BM) and mesenteric lymph nodes (MLN) of conventional and “antigen‐free” mice. These antigen‐free mice were germ‐free raised and fed an ultrafiltered solution of chemically defined low molecular weight nutrients, and thus devoid of exogenous antigenic stimulation. The secretion of IgM, IgG and IgA by spleen, BM and MLN cells was assessed in the protein A plaque assay, while specific IgM antibody‐secreting cells were detected by plaque assays specific for differently haptenated sheep red blood cells.In general, antigen‐free and conventional mice were found to have roughly equal numbers of IgM‐secreting cells in spleen and BM. The number of IgG‐secreting cells in the spleen of antigen‐free mice was the same as in the spleen of conventional mice, but in the BM their number was 3–5‐fold decreased. About one half of the antigen‐free mice did not have MLN, and in the half which did, 5 times less IgM‐ and more than 100‐fold less IgG‐secreting cells were found as compared with conventional mice. The number of IgA‐secreting cells in antigen‐free mice was drastically decreased in all three organs tested.The antibody‐specificity repertoire of the “background” IgM‐secreting cells in the spleen and BM of the antigen‐free and conventional mice was much alike. This indicates that in antigen‐free mice the available antibody repertoires are established independently of exogenous and/or mitogenic stimulation.
HLA‐DR‐4‐associated alloreactivity of an HLA‐DR‐3‐ restricted human tetanus toxoid‐specific T cell clone: inhibition of both reactivities by an alloantiserum
Authors: Umetsu Dale T. , Yunis Edmond J. , Matsui Yoshiki , Jabara Haita H. , Geha Raif S. 
Published: February 2007

AbstractWe present here the first report of a human helper/nducer T cell clone (F6) that specifically recognizes tetanus toxoid (IT) in the context of self‐major histocompati‐ bility complex (MHC) determinant(s) (HLA‐DR3), and in addition recognizes a specific but unrelated MHC determinant(s) in the absence of conventional antigen. Extensive subcloning insured that the cells were progeny of a single cell. Furthermore, removal of the cells proliferating to the alloantigen with bromodeoxyuridine and light removed cells responding to both TT plus self‐MHC and to the stimulating alloantigen, again indicating that F6 was the progeny of a single cell.The alloantigen recognized by this TT‐specific clone appears to be closely linked to HLA‐DR4 since cells from 13 of 14 HLA‐DR4+ donors stimulated F6. An antiserum which recognizes HLA‐DR4, when added to cultures, blocked the alloreactivity of F6, and in addition blocked its proliferation to 'IT plus HLA‐DR3. Absorption of this antiserum with HLA‐DR4+ cells or with IT‐pulsed HLA‐DR3+ cells removed its capacity to inhibit the proliferation of F6. These results suggest that the antigen recognition unit on F6 is stimulated both by allodeterminants expressed on HLA‐DR4 cells and by TT plus HLA‐DR3. These moieties cross‐react at the T cell recogni‐ tion level as well as at the antibody level.