bluuebunny/crossref_metadata_2025 huggingface dataset:
Migration of Prebursal Stem Cells from the Early Chicken Embryo to the Yolk Sac
Authors: LASSILA O. , MARTIN C. , DIETERLEN‐LIÈVRE F. , GILMOUR D. G. , ESKOLA J. , TOIVANEN P.
Published: June 2006

Allogeneic yolk sac—embryo chimaeras were constructed by association of S15B15 yolk sac and B2B2 embryo on day 2 of incubation. Five days later yolk sac cells from the chimaeras were injected intravenously into 14‐day‐old irradiated embryos, using recipients of B2B2 and B15B15 genotypes. One week after hatching, cells in the bursa of Fabricius and peripheral blood erythrocytes were studied for la‐like antigens and B alloantigens, respectively, to determine whether they were derived from the embryo or yolk sac part of the chimaera. The results obtained demonstrate that prebursal and erythropoietic stem cells migrate from the early embryo to the yolk sac during the 2nd to the 7th day of incubation. They also exclude the de novo generation of prebursal stem cells in the yolk sac.
Potentiation of the PFC Response to Thymus‐Independent Antigens by Heterologous Erythrocytes
Authors: WOOD C. , FERNANDEZ C. , MÖLLER G.
Published: June 2006

Immunization with horse erythrocytes (HRBC) and a thymus‐independent (TI) antigen of the TI‐2 category, such as native dextran, dinitrophenyl‐dextran (DNP‐dextran), or DNP‐Ficoll, resulted in a three‐ to four‐fold enhancement of the plaque‐forming cell response to the TI antigen. The effect was found to be T‐cell‐associated, since cyclosporin A abrogated enhancement. The T cells or T‐cell factors involved were elicited early in the response to HRBC and acted on the initial stages of the TI response. The HRBC‐induced potentiation affected only B cells activated by the TI antigen; it could not induce a TI response when TI‐2 antigen was given under nonresponsive conditions; and it had only a slight effect on the response to a thymus‐dependent (TD) antigen. A soluble TD antigen, bovine serum albumin‐coupled dextran (BSA‐dextran), did not have potentiating ability equivalent to that of the paniculate HRBC. It was concluded that non‐specific T‐cell help can influence TI‐2 responses when they are present simultaneously.
Isolation and Identification of a cDNA Clone Coding for an HLA‐DR Transplantation Antigen α‐Chain
Authors: GUSTAFSSON K. , BILL P. , LARHAMMAR D. , WIMAN K. , CLAESSON L. , SCHENNING L. , SERVENIUS B. , SUNDELIN J. , RASK L. , PETERSON P. A.
Published: June 2006

Membrane‐bound mRNA was isolated from Raji cells and enriched for message coding for the HLA‐DR transplantation antigen α‐chain by sucrose gradient centrifugation. Double‐stranded cDNA was constructed from this mRNA fraction, ligated to plasmid pBR322, and cloned into Escherichia coli. By hybrid selection, a plasmid, pDR‐α‐1, able to hybridize with mRNA coding for the HLA‐DR α‐chain was identified. From the nucleotide sequence of one end of the insert an amino acid sequence was predicted which is identical to part of the amino‐terminal sequence of an HLA‐DR α‐chain preparation isolated from Raji cells. This clearly shows that pDR‐α‐1 carries almost the complete message for an HLA‐DR α‐cbain. From the nucleotide sequence of this plasmid it will be possible to predict the primary structure of an HLA‐DR α‐chain.
Modulation of Mouse Natural Killer Cell Activity by the Serum Thymic Factor
Authors: BARDOS P. , BACH J.‐F.
Published: June 2006

After mice had been treated with serum thymic factor (FTS). we observed an increase or a decrease in the NK activity, depending on the duration of treatment and mouse strain: an increase for C57BL/6, BALB/c, A, and nu/nu and a decrease for NZB and CBA mice. The fact that treatment of C57BL/6 mice with FTS produces the same effect as thymeciomy—that is, an increase ‐on the NK activity and returns the augmented NK activity of thymeclomized mice to normal levels suggests that FTS has multiple effects with different results depending on the level of differentiation of the target cells. Different mechanisms of action of FTS on NK cells are discussed.
The Localization of Glomerular C3b Receptor by Immunoelectron Microscopy
Authors: MATRE R. , NILSEN R. , THUNOLD S. , TØNDER O.
Published: June 2006

By an indirect immunopcroxidase technique, rabbit antiserum to solubilizcd C3b receptor stained the glomeruli in cryostat sections of human kidney. The staining was localized to the glomerular basement membrane zone. Glomcruli in sections of aldehyde‐fixed paraffin‐embedded tissue did not stain. However, if the sections were pretreatcd with proteolytic enzymes, the glomeruli were stained by the antiserum as in the cryostat sections. Electron microscopy revealed that the reaction product was located in the cell membrane of the epithelial cells. In some cells the reaction product was also found in vacuoles in the cytoplasm. The basement membrane and endothelial and mesangial cells did not stain.
Transferrin Receptors on Mitogen‐Stimulated Human Thymus‐Derived Lymphocytes
Authors: HAMMARSTRÖM M.‐L. , AXELSSON B. , IVANSEN M. , HAMMARSTRÖM S. , PERLMANN P.
Published: June 2006

The appearance of transferrin receptors on mitogen‐stimulated human thymus‐derived (T) lymphocytes was studied. When indirect immunofluorescence with immunoadsorbent‐purified antitransferrin antibodies was used, ∼ 10% of resting T cells were stained. This proportion increased to 50–80% of the cells 3–4 days after stimulation with the mitogenic lectins concanavalin A (Con A) and leucoagglutinin (La) from Phaseolus vulgaris. Almost all blast cells (≥90%) were positive. Cell binding experiments with 125I‐labelled transferrin indicated the piesence of 1–5×105 transferrin receptor molecules/cell with high avidity for transferrin (K=2–12 × 1081/mol). Analysis by sodium dodecyl sulphate polyacrylamide gel electrophoresis and autoradiography of cell lysates containing 125I‐labelled T‐cell surface components revealed two surface peptides (90 kdaltons and 80 kdaltons, reducing conditions), which selectively bound to insolubilized antitransferrin antibodies. The 90‐kdalton peptide also bound to insolubilized transferrin. The 80‐kdalton peptide is most probably transferrin and the 90‐kdalton peptide the transferrin receptor. Unreduced transferrin receptor had a molecular weight of 180 kdakon. It is probably a glycoprotein, since it reacted with wheat germ agglutinin, La, and probably also Con A. The properties of the lymphocyte transferrin receptor are similar to those described for transferrin receptors on various in‐vitro‐grown transformed cells. This speaks in favour of a common receptor present on all proliferating human cells.
Concanavalin‐A‐Activated Suppressor Cells in Patients with Juvenile Rheumatoid Arthritis
Authors: ASTRUP L. B. , MORLING N. , RYDER L. P. , FRIIS J. , PEDERSEN F. KARUP , SVEJGAARD A.
Published: June 2006

Concanavalin‐A‐induced suppressor cell activity was investigated in 63 patients with a definite diagnosis of juvenile rheumatoid arthritis. Peripheral blood lymphoid cells from these patients did not have the same ability as cells from normal individuals to suppress the proliferative response of autologous cells, responding to phytohaemaglutinin, Candida albicans antigen, or allogeneic cells. No correlation was found between suppressor activity, disease activity, or number of joints involved. Nor was there any significant association between decreased suppressor cell activity and HLA‐A, ‐B, ‐C, ‐D antigens, although there was a tendency towards association between decreased suppressor cell activity and HLA‐B27.
In Vitro Immune Response of SLE Lymphocytes
Authors: TAKEUCHI T. , ABE T. , KIYOTAKI M. , TOGUCHl T. , KOIDE J. , MORIMOTO C. , HOMMA M.
Published: June 2006

Peripheral blood lymphocytes from 26 patients with systemic lupus erythematosus (SLE) and six normal individuals were tested for IgG synthesis in the presence or absence of PWM. Lymphocytes from patients with active SLE synthesized increased amounts of IgG in the absence of PWM and reduced amounts of IgG in the presence of PWM. Serum from patients with active SLE had an enhancing effect on the in vitro IgG synthesis of normal lymphocytes. The IgG or F(ab′)2 fractions of SLE serum retained the enhancing effect on in vitro IgG synthesis, and the enhancing activity was absorbed by human spleen cells. As little as 4 h of incubation with SLE serum was needed for the enhancing activity of normal lymphocytes. Treatment of B lymphocytes appeared to be of main importance for an increase in the in vitro IgG synthesis of SLE serum‐treated lymphocytes. These results suggest that anti‐B‐lymphocyte antibodies from patients with active SLE are responsible in part for the hyperactive response of SLE B lymphocytes.
IgG‐ and IgM‐Induced Cellular Cytotoxicity
Authors: ZÖLLER M. , HEYMAN B. , ANDRIGHETTO G. , WIGZELL H.
Published: June 2006

The actual existence of IgM‐induced antibody‐dependent cell‐mediated cytolysis (ADCC) is still a matter of debate. In the preseni study four IgM anti‐sheep erythrocyte (SRBC) and one IgM anti‐trinitrophenyl (TNP) monoclonal hybridomas have been studied for their ability to produce antibodies with ADCC‐inducing capacity. All five hybridomas were shown to release into the culture supernatant antibodies with specific ADCC‐inducing capacity. Compared with IgG‐induced ADCC, however, much higher concentrations of IgM antibodies were necessary. To exclude the possibility that low numbers of IgG antibodies could be present in the culture supernatams, derived from hypothetical switching of hybridoma cells from IgM to IgG, several sets of controls were performed. Positioning of the inducing antibody with regard to size agreed with it being of IgM nature. Passage through protein A (PA)‐Sepharose columns removed no ADCC activity from the IgM hybridoma supernatants while completely retaining the activity from IgG hybridoma supernatant. In contrast, after passage over a concanavalin A (Con A)‐Sepharose column, ADCC activity from IgM hybridoma supernatants was recovered in the bound and eluted fraction. Addition of aggregated human gammaglobulin (aggHGG) caused a complete inhibition of IgG‐induced ADCC but did not significantly inhibit IgM‐induced ADCC. Finally, trypsin treatment of the effector cells removed their ability to function in IgM ADCC, but IgG ADCC was left largely intact. We conclude from the above findings that IgM antibodies can function in ADCC in the absence of IgG antibodies, although their efficiency on a molar basis is significantly inferior to that of IgG antibodies.
The Role of HLA‐DR Antigens in PPD‐stimulated Lymphocyte‐Monocyte Interactions
Authors: HAAR D. , HERON I.
Published: June 2006

Autologous monocytes arc required for an optimal lymphocyte proliferative response to purified protein derivaie of tuberculin (PPD) in vitro and for a mixed lymphocyte culture induced by alloantigens. In the proliferative response to PPD we found that autologous monocytes could be replaced with HLA‐DR‐compatible monocytes and partly with HLA‐DR semi‐identical. In spite of a statistically significant difference between autologous and HLA‐DR disparate monocytes in their cooperative capacity with PPD‐stimulated lymphocytes, replacement in nearly one third of the cases was possible. These findings were supported by more detailed studies in which increasing numbers of allogeneic and autologous monocytes were added to the isolated lymphocytes in the presence of PPD. It is concluded that the serologically defined HLA‐DR antigens alone give insufficient information of the restriction elements controlling the PPD‐stimulated lymphocyte‐monocytc interactions.
Quantitation of Cells Secreting Immunoglobulins after Elution from Rheumatoid Synovial Tissue
Authors: EGELAND T. , LEA T. , MELLBYE O. J. , PAHLE J. A. , OTTESEN T. , NATVIG J. B.
Published: June 2006

Mononuclear cells (MNC) eluted from rheumatoid synovial tissue of 16 patients with rheumatoid arthritis were examined for immunoglolulin‐secreting cells (ISC). Immediately after elution and separation synovial tissue MNC contained considerable numbers of ISC. IgG and IgA ISC were more abundant than IgM ISC. At the same time there were low numbers of ISC in blood. Synovial tissue ISC were lost during incubation with pokeweek mitogen (PWM), possibly because tissue MNC were already maximally triggered in vivo. This was in contrast to blood MNC, in which the number of ISC increased significantly during incubation with PWM.
Ribonucleic Acid Antigen from the Reiter Treponeme Used in an ELISA for Antibodies in Syphilis
Authors: PEDERSEN N. STRANDBERG , PETERSEN C. SAND , AXELSEN N. H.
Published: June 2006

Purified RNA from Treponema phagedenis biotype Reiter was used as antigen in an enzyme‐linked immunosorbent assay (ELISA) for IgG antibodies in syphilis. The RNA ELISA was compared with the fluorescent treponemal antibody absorption test (FTA‐ABS), the Treponema pallidum immobilization test (TPI), and with two ELlSAs using purified flagellum from the Reiter treponeme as antigen (flagellum ELISA), and sonified Reiter treponeme culture as antigen (sonicate ELISA). A total of 729 sera from patients with and without syphilis were studied. The RNA ELISA had a lower sensitivity (P < 0.01) in primary syphilis than the ftagellum ELISA, the sonicate ELISA, and the FTA‐ABS. In treated syphilis the RNA ELISA was also less sensitive than the TPI (P < 0.01).
Transfer of Lesions of Allergic Encephalomyelitis in Sheep with Cell‐Free Lymph from Animals Sensitized with Homologous Spinal Cord plus Adjuvant
Authors: WILLENBORG D.O.
Published: June 2006

An experiment was designed to test the hypothesis that the inability to transfer experimental allergic encephalomyelitis (EAE) with serum from sensitized animals was due to the absorption, from the serum, of the relevant antibodies by the target organ of the donor. The immune response to central nervous system (CNS) antigens was isolated to a single lymph node, and the cell‐free lymph coming from the node was shown to transfer lesions of EAE to naive recipients. These results are compatible with the hypothesis; however, the antibody nature of the transfer activity has yet to be established.
Natural Killing and Antibody‐Dependent Cytotoxicity by T Leukaemic Blasts from Acute Lymphoblastic Leukaemia
Authors: GUPTA S. , FERNANDES G.
Published: June 2006

Bone marrow T leukaemic blasts from four patients with T‐cell acute lymphoblastic leukaemia (ALL) were examined as effectors in natural killing (NK) and antibody‐dependent cytotoxicity (ADCC). T leukaemic blasts demonstrated both NK (against K‐562 cells as targets) and ADCC (against chicken erythrocytes (CRBC) and cells of SB cell line as targets). NK activity and ADCC (against SB cells) were comparable to NK and ADCC (against SB cells) of peripheral blood T cells from healthy controls. ADCC against CRBC by leukaemic blasts was lower than that of peripheral T cells from normal controls. Of leukaemic blasts 20–42% possessed IgG Fc receptors. This study demonstrates that T leukaemic blasts are effectors in NK and ADCC assays.
Anti‐Ia‐reactive Cells in the Urinary Tract of Man, Guinea‐Pig, Rat and Mouse
Authors: HJELM E. , FORSUM U. , KLARESKOG L.
Published: June 2006

Tissues from the urinary tract of man, the guinea‐pig, mouse and rat were investigated for la (HLA‐DR) tissue distribution with an immunohistochemical staining technique using anti‐Ia monoclonal antibodies. Human and guinea‐pig tissues were also investigated with a rabbit anti‐human HLA‐DR immunoglobulin. Ia‐antigen‐expressing cells were demonstrated in bladder connective tissue of man, the guinea‐pig, rat and mouse. In man and the guinea‐pig anti‐Ia‐reactive cells were present also in the bladder epithelium. In the kidney, the Ia antigens seemed to be restricted to the endothelium in man, the guinea‐pig and mouse, whereas in the rat, the kidney contained anti‐Ia‐reactive dendritic cells in the inter‐stitium. The staining of mouse tissues with anti‐I‐Ak‐ and anti‐I‐E/Ck‐specific monoclonal antibodies revealed that cells of different Ia phenotypes were differently distributed in the bladder connective tissue. In sections from the mouse kidney no difference in staining was seen with the various antibodies. In experiments with mouse bone‐marrow chimeras the anti‐Ia‐reactive cells in mouse bladder were shown to be of bone‐marrow origin. In humans epithelial Ia‐expressing cells could be isolated from the urine. Such cells might constitute a source of anti‐Ia‐reactive epithelial cells for future functional studies.
T‐Cell Subsets Induced in Listeria monocytogenes Immune Mice
Authors: KAUFMANN S. H. E. , HAHN H. , SIMON M. M.
Published: June 2006

Interactions of peritoneal exudate T lymphocytes from listeria‐immune mice with macrophages from normal mice in the presence of heat‐killed listeriae result in the induction of interleukins. The data show that Ly 1+, 23‐ T cells specific for listeria antigens are essential for interleukin induction and make it likely that, in addition, Ly 1+, 23+ T cells are required for optimal responses.
Both DR and MT Class II HLA Molecules May Restrict Proliferative T‐Lymphocyte Responses to Antigen
Authors: BERLE E. J. , THORSBY E.
Published: June 2006

Antigen‐primed T‐cell blasts may be separated from alloreactive T cells on Percoll gradients. By means of this method, HLA restriction of antigen‐specific proliferative T‐cell responses may be studied, using allogeneic antigen‐presenting cells carrying foreign D/DR antigens. The reported data confirm that the D/DR molecules as such are major restriction elements in the T‐cell response to herpes simplex virus (HSV) and purified protein derivative (PPD). However, evidence is presented that other Class II HLA molecules, the MT molecules, may also function as restriction elements for the HSV response.
HLA‐D/DR Restriction of Langerhans Cell‐Dependent Antigen Activation of T Lymphocytes
Authors: BERLE E. J. , BRAATHEN L. R. , THORSBY E.
Published: June 2006

In previous studies we have shown that the response of T cells to antigen presented by epidermal Langerhans cells (LC) is restricted by products of the HLA‐D region. An optimal antigen‐specific response required that the LC used for antigen presentation shared both, or at least one, of the D/DR determinants of the T‐cell donor. These studies were, however, disturbed by a strong allogeneic response induced by the foreign D/DR determinants of the LC. We report here that by separating the antigen‐specific T cells from those that are alloreactive, a clearer picture of the D/DR restriction phenomenon may be obtained. Furthermore, the present studies demonstrate that the same D/DR determinants function as restriction elements on peripheral blood monocytes and LC.
Functional Activity of a Transformed Thymic Epithelial Cell Line
Authors: GLIMCHER L. H. , KRUISBEEK A. M. , PAUL W. E. , GREEN I.
Published: June 2006

In an attempt to obtain pure populations of nonlymphoid thymic cells, monolayers of thymic cells enriched for low‐density cells were transformed with SV40. This paper describes the characteristics of the initial cell lines which resulted from this approach. These cell lines appeared to be of epithelial origin by morphologic criteria (extensive surface microvilli and pronounced intercellular tight functions) and by biochemical analysis, since they possessed mouse keratin proteins. They did not possess I‐region‐associated antigens on their surface, markers that have been detected on normal thymic epithelium. Functionally, these transformed cell lines secreted a factor capable of inducing thymocytes to mature to functional cytotoxic effector cells directed against allogeneic stimulators. This factor did not appear to be interleukin 1, interleukin 2, or colony‐stimulating factor; did not result in thymocyte proliferation; and did not affect peripheral T cells. The cell lines described in this report should prove useful in delineating the steps by which immature T cells acquire their immunocompetence in the thymus.
Naturally Cytotoxic Tonsillar Lymphocytes: A Manifestation of Heterogeneity among Human NK Cells
Authors: KIMBER I. , MOORE M.
Published: June 2006

Lymphocytes isolated from human tonsils are capable of lysing cells or the natural killer (NK)‐susceptible line K562. Although weak compared with that of autochthonous peripheral lymphocytes, cytotoxicity is invariably manifest at high effector‐to‐target ratios. Like peripheral NK cells, tonsillar cytotoxic lymphocytes possess a low buoyant density, which makes possible their partial enrichment from non‐cytotoxic cells by centrifugation on discontinuous Percoll gradients. However, examination of cytotoxic fractions indicates that, unlike blood lymphocyte‐mediated cytotoxicity, effector function is not associated with the presence of large granular lymphocytes. Furthermore, a functional distinction from classical NK cells is apparent since, although tonsillar cytotoxicity is significantly enhanced after exposure to supematants from polyclonally activated allogeneic tonsils, pretreatment with lymphobtastoid (Namalva) interferon (IFN‐α) at doses shown to potentiate maximally the cytotoxicity of peripheral blood lymphocytes fails to influence reactivity. These data provide preliminary evidence for the existence of, at least limited, heterogeneity among human NK cells.
Breakdown Product of Factor B as an Index of Complement Activation in Lepromatous Leprosy and Its Relation with Bacillary Load
Authors: SAHA K. , SHARMA V. , CHAKRABARTY A. K. , SEHGAL V. N.
Published: June 2006

Serum complement profile studied in 50 lepromatous leprosy patients with various bacillary loads demonstrated significantly decreased C3 levels in patients with high bacteriological index (2+ to 4 +) as compared with those with lesser bacterial load. In contrast, mean serum levels of Cl q and C4 components remained unchanged. The concentration of factor B breakdown product (Ba) and its ratio to factor B increased with the bacterial density and more so in patients with erythema nodosum leprosum. A significant negative correlation was found between serum C3 and Ba levels in most lepromatous patients. Analysis of the data suggested the alternative pathway as the possible mechanism of complement activation in lepromatous leprosy.
Mitogen‐Induced Switching of Immunoglobulin Heavy‐Chain Class Secretion in Chronic B‐Lymphocytic Leukaemia and Immunocytoma Cell Populations
Authors: JULIUSSON G. , ROBÈRT K.‐H. , HAMMARSTRÖM L. , SMITH C. I. E. , BIBERFELD G. , GAHRTON G.
Published: June 2006

Lymph nodes from peripheral blood, bone marrow, and lymph nodes from six patients with chronic B‐lymphoproliferative disease were studied. Two of the patients had a polymorphic immunocytoma with surface membrane immunoglobulin phenotype μκ. Four patients had chronic B‐lymphocytic leukaemia (CLL) with the phenotypes μκ, μδκ, μγ, and μδγ, respectively. In no case did the monoclonal cell populations express γ chains on the surface, and none produced monoclonal immunoglobulin in vivo. The malignant B lymphocytes were cultured in the presence of polyclonal B‐cell activators. Immunoglobulin secretion was detected with the protein A plaque assay and with a modification of the reversed haemolysis‐in‐agar plaque assay. Immunoglobulin secretion was induced in four of the cell populations; In both the immunocytomas and in one of the CLL cell clones the heat‐inactivated Staphylococcus aureus strain Cowan I induced secretion of IgG, as well as IgM, associated only with the same light chain as was expressed on the surface of the unstimulated cells. Thus, mitogens can induce immunoglobulin secretion in vitro in malignant B lymphocytes, and Cowan I bacteria also have the ability to induce a switch of immunoglobulin production from IgM to IgG in a fraction of the leukaemic cell populations.
Antigenic and Immunogenic Components in Rat Liver
Authors: LAUTENSCHLAGER I. , NYMAN N. , VÄÄNÄNEN H. , LEHTO V. P. , VIRTANEN I. , HÄYRY P.
Published: June 2006

We have analysed the immunogenic potential and the expression of class II major histo‐compatibility complex (MHC) antigens of the various cellular components of rat liver. A two‐step fractionation procedure was developed to isolate the following liver cellular components: hepatocytes, ‘non‐hepatocytic’ parenchymal cells, and passenger leucocytes including the Kupffer cells. A primed rejection assay with the different isolated cell populations was performed in the WF rat. The survival time of a DA cardiac allograft in a normal, non‐primed WF rat is 6.3 ± 2.1 days. DA liver hepatocytes were unable to induce accelerated rejection, reducing the survival to at most 5.5 ± 0.6 days (P= 0.374). The hepatocyte‐depleted parenchymal cell component, consisting primarily of endothelial and bile duct cells, was equally ineffective and reduced the survival to at most 5.0 ± 1.4 days (P=0.453). An accelerated rejection was obtained only with the liver passenger cell‐enriched fraction, with a reduction of survival to 3.3 ± 0.6 days (P=0.034). The expression of class II MHC antigens was analysed on frozen sections and on the disaggregated liver cells by using monoclonal mouse antisera to the common part of the class II molecule. Indirect immunofluorescence and cytological Staphylococcus aureus Cowan I rosette assays were used, respectively. The former showed that only the vascular endothelial cells and the Kupffer cells of the space of Disse expressed class II; the latter demonstrated that only the Kupffer cells had substantial amounts of class II antigens on the cell surface. The results demonstrate that the principal and perhaps only immunogenic component in rat liver is the passenger leucocytes, in particular the strongly class‐II‐expressing Kupffer cells of the passenger population.
Heterogeneity of Human Amyloid Protein AA and Its Related Serum Protein, SAA
Authors: SKOGEN B. , SLETTEN K. , LEA T. , NATVIG J. B.
Published: June 2006

The heterogeneity of the human amyloid proteins SAA and AA was studied. Both proteins could be separated into several fractions by ion‐exchange chromatograpby. Amino acid analysis of the ion‐exchange‐chromatographed fractions of protein AA showed that the main difference was in the length of the polypeptide. Thus, it seems that the original AA preparation consists of a mixture of AA proteins with length ranging from 66 to 78 amino acid residues. By enzymatic degradation of three different forms of SAA with kallikrein, fragments were formed with a molecular weight very similar to thai of protein AA.
Cytochemical Analysis of Human Peripheral Blood Lymphocyte Subsets Defined by Monoclonal Antibodies
Authors: BERNARD J. , DUFER J.
Published: June 2006

Human blood lymphocyte subpopulaiions, revealed by a panel of commercially available monoclonal antibodies by means of a resetting technique, were submitted to direct cyto‐chemicat analysis and were shown to have distinguishing characteristics. T cells reactive with OKT3 antibody (T3+) displayed higher beta‐glucuronidase and dot‐like alpha‐napnthyl acetate acid esterase (ANAE) activity than T3− cells. Helper/inducer cells (T4+) were characterized by a high level of dot‐like ANAE activity, whereas cytotoxic/suppressor cells (T8+) displayed selective naphthol‐ASD‐chloroacetate esterase activity. These results provide evidence for association of some cytoplasmic enzyme activities with the expression of membrane differentiation markers defined by monoclonal antibodies.
Natural Killer‐like Cytotoxicity of Human T‐Cell Clones against Various Target Cells
Authors: LÓPEZ‐BOTET M. , MORETTA A. , MORETTA L.
Published: June 2006

MLC‐T cells from two different donors were cultured after limiting dilution (0.3 cells/well) in medium containing T‐cell growth factor. Clones showing lytic activity against K‐562 in a preliminary screening were expanded and tested against various NK‐sensitive targetcell lines (Chang, T‐24, Daudi, and Molt‐4) and phytohaemagglutinin blasts derived from the stimulator cells. Ten growing clones maintained their activity against K‐562 and were able to lyse the other cell lines. A significant heterogeneity was nevertheless noticed in the lytic efficiency of the different clones against the various target cells. Taken together, our data indicate that single clones are able to lyse different NK‐sensitive targets.
Two Distinct Azobenzenearsonate‐Specific Helper T‐Cell Subpopulations Mediate Different Forms of T‐B Cooperation
Authors: ADORIMI L. , AGAROSSI G. , FIORAVANTI D. , DORIA G.
Published: June 2006

Popliteal lymph node T cells from mice footpad‐primed with azobenzenearsonate (ABA)‐protein conjugates were able to help the anti‐trinitrophenyl (TNP) and anti‐ABA plaque‐forming cell (PFC) responses of normal syngeneic spleen cells cultured in vitro with TNP‐ABA‐keyhole limpet haemocyanin. Enrichment in ABA‐specific helper cells was obtained by positive selection of ABA‐primed T cells on ABA‐pulsed syngeneic macrophages. The ABA‐specific T cells induced by ABA‐protein priming are able to help the anti‐TNP PFC response of normal B cells through recognition of the ABA determinant either unlinked to TNP (ABA and TNP separately presented to T and B cells) or linked to TNP (ABA and TNP presented as moieties of the same molecule). These two mechanisms of T‐B cooperation are mediated by two different ABA‐specific helper T‐cell subpopulations, which can be distinguished by their different radiosensitivities: the former mechanism is mediated by radioresistant T cells, whereas the latter is mediated by radiosensitive T cells. Both helper T‐cell subpopulations bind the ABA‐pulsed syngeneic macrophages, demonstrating the presence of ABA‐specific receptors on both cell types.
Ox Erythrocyte Cytotoxicity by Phorbol Myristate Acetate‐Activated Human Neutrophils
Authors: DALLEGRI F. , PATRONE F. , BONVINI E. , GAHRTON G. , HOLM G. , SACCHETTI C.
Published: June 2006

Human neutrophils activated by phorbol myristatc acelatc were cytoioxic lo ox erythrocyles. as determined by the 51Cr release method. Maximal cytolysis was obtained with a phorbol myristute acetate concentration of 5 ng/ml and with an etTcctor to target cell ratio of 1:4. An inlact neutrophil metabolic burst and production of oxygen‐dcrived‐frec radicals were essential lor the cytotnxic event, since neulrophils from patients with chronic granulo‐malous disease failed to exhibit any ox erythrocyte lysis. The target cell destruction was completely prevented by catalase, was unaffected by supcroxidc dismutase. and was reduced approximately to one‐third by azide and cyanide. These data suggest that, under our experimental conditions, the ox erythrocyte killing by phorbol myristatc acetate‐activated neutrophils mainly depends on myelopcroxidasc and hydrogen peroxide.
Fatal Meningitis following Lymphocytic Choriomeningitis Virus Infection Reflects Delayed‐Type Hypersensitivity Rather than Cytotoxicity
Authors: THOMSEN A. RANDRUP , BRO‐JØRGENSEN K. , VOLKERT M.
Published: June 2006

Fatal meningitis following intracerebral inoculation of lymphocytic choriomeningitis virus (LCMV) reflects an immunopathological lesion believed to be mediated by cytotoxic T cells. The results presented here demonstrate that pretreatment with cyclophosphamide (Cy; 150mg/kg body weight) 2 days before intracerebral infection significantly reduced the lethality of the infection. However, this treatment did not impair the antiviral cytotoxic response as measured in the spleen. On the other hand, virus‐specific delayed‐type hyper‐sensitivity (DTH) was significantly reduced. This reduction seems to be the result of a Cy‐induced lack of non‐committed ancillary cells since: (1) virus‐primed spleen cells from Cy‐pretreated donors conferred normal LCMV‐specific DTH to naive recipients; (2) transfer of virus‐primed spleen cells from untreated donors did not increase the suppressed DTH response of the Cy‐pretreated mice: and (3) inoculation of irrelevant antigen and antigen‐primed spleen cells into the footpads of Cy‐pretreated, infected mice resulted in a significantly reduced footpad swelling as compared with untreated, infected controls. Taken together, these results indicate that LCMV‐induced meningitis does not solely represent T‐cell‐mediated cytotoxicity in vivo but that a fatal outcome of the infection critically involves not only effector T cells but also ancillary cells.
Age‐Related Loss of Function of Alloactivated Interleukin 2‐Propagated Human Primed Lymphocyte Typing Clones
Authors: PAWELEC G. , SCHNEIDER E. M. , REHBEIN A. , SCHAA I. , WERNET P.
Published: June 2006

Human lymphocytes alloactivated in vitro were cloned by limiting dilution in the presence of filler cells and interleukin 2 (IL 2)‐containing supernatants of phytohaemagglutinin‐stimulated lymphocytes. Clones with allospecific proliferative reactivity (PLT clones), measured by tritiated thymidine (3H‐TdR) incorporation, were selected for extensive IL 2‐dependent expansion. The cloned lines had finite lifespans, ranging from an estimated minimum of 28 to > 65 doublings. Function as PLT reagents, however, was retained in all cases for only an estimated 30 cell doublings. This apparent cessation of function was not caused by loss of the ability to metabolize thymidine, since lines continuing to grow for > 30 doublings still incorporated 3H‐TdR in the presence of IL 2. An altered requirement for stimulating antigen (number of stimulating cells), or altered response kinetics, did not contribute to loss of PLT function. Exogenous IL 2 added during restimulation to responders previously ‘rested’ overnight without IL 2 did not restore the response. Thus, under present experimental conditions, functional lifespans of cloned PLT reagents appear fixed at ˜ 30 cell doublings.
Delineation of Subsets in Human B‐Cell Lymphomas by a Set of Monoclonal Antibodies Raised against B Lymphoma Cells
Authors: FUNDERUD S. , LINDMO T. , RUUD E. , MARTON P. F. , LANGHOLM R. , ELGJO R. FØLUNG , VAAGE S. , LIE S. , GODAL T.
Published: June 2006

Murine hybridoma antibodies to a human B‐cell lymphoma were developed. After screening against normal T cells, monocytes, and grunulocytes 11 antibodies that reacted with cells from other B‐cell lymphomas remained, of which 10 showed individually distinct staining patterns, as tested by indirect fluorescence. When tested against lymphomas or cell lines, none of these antibodies revealed staining patterns suggesting reactivity with conventional B‐cell surface markers, such as immunoglobulin, complement factor 3 receptors, or HLA‐DR antigens. Only one of the antibodies (GB1) reacted with human serum, as determined by a blocking assay. The antibodies were found to belong to different immunoglobulin isotypes. Two antibodies (GB13 and GB14) reacted with >5% of normal peripheral blood monnnuclcar cells. These reactions were mainly due to reactivity with B cells. The antibodies reacted only in a few cases with acute leukaemias, B‐ccll lines, and follicular lymphomas. On the other hand, distinct patterns of reactivity in different histological groups of diffuse lymphomas were obtained, suggesting that the antibodies may be useful in delineating phenotypic subsets among human B‐cell lymphomas.
Spontaneous Reverse Haemolytic Plaque Formation
Authors: LIBRACH C. L. , BURNS G. F.
Published: June 2006

A sensitive reverse haemolytic plaque assay was used on freshly isolated blood cells from normal human subjects to show that T lymphocytes and monocytes were both necessary for immunoglobulin production by unstimulated B celts cultured only for the time necessary to form plaques. When lymphocyte preparations were fully depleted of T cells by E‐rosette formation overnight on ice followed by Ficoll‐Hypaque centrifugation, the number of plaque‐forming cells was reduced by up to 94%; this reduction was reversed by the replacement of T cells, although excess T cells suppressed plaque formation. Moreover, when T‐cell function was blocked by 10–1000 ng of two monoclonal anti‐T‐cell antibodies, OKT3 or UCHT1, this significantly reduced or abolished spontaneous IgG plaques, and higher concentrations of either OKT3 or UCHT1 reduced the numbers of IgA and IgM plaques formed by B cells. The role of monocytes in spontaneous plaque formation was investigated. The removal of plastic‐adherent cells from mononuclear cell preparations did not consistently result in a reduction in the numbers of plaques, but complement‐mediated lysis of monocytes with either of two monoclonal antibodies with specificity for monocytes. OKM1 and FMC17, reduced by 50% the number of IgG, IgA and IgM plaques. This effect was reversed by addition of as few as 1% plastic‐adherent cells. Decreased plaque formation by B cells, resulting from either blocking of T‐cell function with monoclonal antibody or complement‐mediated lysis of monocytes, or both, was fully reversed by soluble factors present in cell‐free conditioned medium from letin‐activated T cells. Thus spontaneous plaque formation by human peripheral blood B cells requires T cells and a small number of monocytes, and the major function of these cells is to help B cells by the production of soluble factors.
Origin of Peripheral Blood Macrophages in Bursa‐Cell‐Reconstituted Chickens
Authors: VAINIO O. , PECK R. , KOCH C. , TOIVANEN A.
Published: June 2006

MHC class‐I antigens on peripheral blood macrophages and bursa cells were analysed after adoptive bursa cell transfer to cyclophosphamide‐treated immunodeficient chickens. We studied the expression of B‐F locus‐encoded antigens (B‐F is homologous to mouse H‐2K, D) on macrophages and B cells and found that macrophage B‐F antigens are of host origin, whereas bursa cells express only donor‐type B‐F antigens. Both syngeneic and allogeneic bursa cells restored IgM antibody production to a T‐cell‐independent antigen, Brucella, but only syngeneic bursa cells could restore the IgG antibody response to a thymus‐dependent antigen, sheep erythrocytes. The results indicate that B‐cell maturation and macrophage‐B‐cell interaction are not MHC‐restricted but that a restriction exists in T‐cell‐B‐cell collaboration.
Alternative Non‐Immune F(ab')2‐Mediated Immunoglobulin Binding to Group C and G Streptococci
Authors: ERNTELL M. , MYHRE E. B. , KRONVALL G.
Published: June 2006

We tested 140 bacterial strains representing 19 different species for binding or purified radiolabelled F(ab')2 fragments prepared by pepsin digestion of polyclonal and monoclonal human IgG. Both polyclonal and monoclonal F(ab')2 fragments showed positive binding to group C and G streptococci with maximum uptake levels of 50% and 85%. Binding was obtained both with fresh bacteria and with organisms stabilized by heat treatment. F(ab')2 fragments of two human IgG1 myeloma proteins with anti‐staphylolysin specificity showed a similar binding pattern. IgG present in normal human serum inhibited the uptake of F(ab')2 fragments, whereas albumin and fibrinogen and purified Fc fragments prepared by papain digestion of polyclonal IgG and monoclonal IgG1 did not show such capacity. Fourteen human myeloma proteins representing IgA, IgM and the four IgG subclasses were tested for inhibiting capacity. Reactivity was noted with at least one myeloma protein within each IgG subclass but not with IgA or with IgM monoclonal proteins. Normal rabbit serum was as inhibitory as normal human serum, whereas dog serum was less reactive. These data demonstrate that group C and G streptococci carry a heat‐stable surface component interacting with the F(ab')2 portion of the IgG molecule. The results suggest that the reactive site on the immunoglobulin molecule may reside in the more constant part of the variable domain. This new reactivity is different from the previously known non‐immune reaction involving the IgG Fc portion. This alternative non‐immune reactivity is analogous to but distinct from the alternative protein A reaction in Staphylococcus aureus.
Interaction of Fibronectin with Complement Component C3
Authors: HAUTANEN A. , KESKI‐OJA J.
Published: June 2006

The activation of the complement component C3 generates C3a and C3b fragments, and the physiological cleavage of C3b further yields C3c and C3d fragments. We studied here by enzyme immunoassay the ability of human plasma fibronectin to interact with native C3 of human sera and with isolated C3c and C3d fragments of C3. C3 from sera of all six individuals tested bound to solid‐phase fibronectin. Soluble fibronectin bound to solid‐phase C3c and C3d, and fluid‐phase C3c and C3d also bound to solid‐phase fibronectin. The binding of fibronectin to solid‐phase C3c and C3d could be inhibited by fluid‐phase C3c and C3d. The results suggest the possibility that soluble fibronectin may attach to C3‐coated particles or that C3‐coated particles may adhere to fibronectin‐containing structures.
Antibody‐Secreting Cell Precursor Frequencies among the Sheep Erythrocyte‐Binding Cells of Non‐Immune Mice
Authors: MARTÍNEZ‐MAZA O. , FEHNIGER T. E. , ASHMAN R. F.
Published: June 2006

The clonal selection theory, as formulated by Burnet, predicts that a lymphocyte bearing receptors for a given antigen will, upon activation, produce antibody to that same antigen. This prediction has for the first time been quantitatively confirmed, by precursor frequency analysis of highly purified sheep erythrocyte antigen‐binding cells (SRBC‐ABC), isolated from the spleens of non‐immune mice, by means of an LPS‐driven limiting dilution micro‐culture system. These precursor frequencies indicated that virtually every non‐immune SRBC‐ABC that was a precursor for the secretion of IgM (or IgG) was also a precursor for the secretion of SRBC‐specific IgM (or SRBC‐specific JgG), after correction for non‐SRBC‐ABC B cells contaminating the SRBC‐ABC preparations. These data help to clarify the relationship between antigen‐binding cells and the antigen‐reactive cells of the clonal selection theory. In the course of making this observation, it was also shown that the precursor frequency of purified non‐immune SRBC‐ABC for IgG production was the same as that of unfractionated cells, whereas the precursor frequency for IgM production and LPS‐induced thymidine incorporation were both lower in the ABC. The clone size estimates for IgM and IgG precursors in ABC and unfractionated cells all fell within a narrow range (1 to 2 doublings).
Tumour‐Host Interactions in Vivo
Authors: GAUDERNACK G. , OLSTAD R.
Published: June 2006

We have earlier shown that coculture of macrophages and cells from a methylcholanthiene‐induced sarcoma (MCI M‐AA) in vitro resulted in macrophage activation and production of type II (gamma) interferon. When ascites fluid from the MCIM‐AA sarcoma (shown previously to activate macrophages in vitro) was added to spleen cell populations from semisyngeneic C3D2 mice in vitro. NK activity was markedly enhanced. After intraperitoneal injection of MCI M‐AA cells or ascites fluid, 4‐ to 12‐fold increased NK cell activity with a peak at 3–5 days could be measured in the spleen cell population and in the non‐adherent peritoneal exudate cell population. The mice injected with tumour cells or ascites fluid developed a pronounced splenomegaly, and maximum spleen size coincided with peak NK activity. Injection of tumour cells or tumour ascites fluid resulted in marked changes in the T‐cell, B‐cell, macrophage, and ‘null’ cell content of ihe peritoneal exudate.
In Vivo Elimination of Allogeneic Lymphocytes in Normal and T‐Cell‐Deficient Rats
Authors: TØNNESEN B. , ROLSTAD B.
Published: June 2006

The distribution of allogeneic and syngencic thoracic duct lymphocytes was studied over 24 h in normal and T‐cell‐dcficient animals (thymectomized, irradiated rats.‘B rats’, or congenitally athymic nude rats). Initial migration from blood was no less for allogeneic than for syngencic cells. After 24 h, however, a marked deficit of radioactively labelled allogeneic cells as compared with syngeneic cells was found in the lymphoid tissue, whereas the allogeneic isotope was recovered in a relatively greater amount in liver, kidneys, and cell‐free plasma and lymph. Most of the allogeneic cells are evidently destroyed within the first 24 h and their isotope released into body fluids. Our studies also revealed this process to be even more evident in T‐cell‐depleled environments. Autoradiographic studies of recipient nude rat spleens showed that allogeneic cells were not found in the great number seen in syngeneic transfers, but a high grain density in the periarteriolat lymphocyte sheath area could be observed. Granula seemed to be predominantly located over large non‐lymphoid cells. The elimination of allogeneic lymphocytes is therefore governed by mechanisms independent of an intact thymus and may be due to a cell population or factor more active in nude animals than in their non‐nude littermates.
Lymphoid Cell Responses to Bacterial Cell Wall Components: Murine B‐Cell Responses to a Purified Cell Wall Moiety of Actinomyces
Authors: KIMUR S. , HAMADA A.S. , TORII M. , MORISAKI I. , KOOPMAN W.J. , OKADA H. , MICHALEK S. M. , McGHEE J. R.
Published: June 2006

A mitogenic component, designated fraction C (Fr C), has been purified from a mutanolysin enzyme digest of Actinomyces cell walls by CM Sephadex C‐25 ion‐exchange and G‐100 gel filtration chromatography. Good mitogenic responses were obtained with Fr C over a broad dose range with peak mitogcnesis seen with 500 μg/culture. Fraction C (mol. wt. = 35,000–40,000) consists of 755 carbohydrate and 23% protein, is non‐dialy‐sable, resistant to heat, lysozyme or protease treatment, and partially sensitive to base, and all milogenic activity is destroyed by cither periodate or acid treatment. Fraction C is a B‐cell mitogcn since it induced responses in nude (nu/nu) and nu/+ BALB/c spleen cell cultures and purified splenic B‐cell cultures, but did not stimulate purified splenic T‐cell cultures. Similar milogenic fractions for B cells have been obtained from cell walls of A naeslundii and from a human isolate of A. viscosus. Good polyclonal IgM synthesis and plaque‐forming cell responses to hapten or erythrocytes were obtained in vitro with the purified cell wall fractions derived from all three Actinomyces strains studied. These results indicate that the Actinomyces cell wall possesses a carbohydrate‐rich component which activates B cells und may represent a common determinant of this genus.
The Ontogeny of T‐Cell Antigens in the Thymus
Authors: GILHUS N.E. , MATRE R.
Published: June 2006

T‐cell‐specific antigens were examined in tissue sections of thymus from 24 fetuses, infants, and children. OKT6 monoclonal antibodies faintly stained some thymocytes at 11 weeks of gestation, whereas OKT3, OKT4 and OKT8 did not stain the thymocytes before 14 weeks of gestation. OKT4, OKT6 and OKT8 preferentially stained the cortical thymocytes, in contrast to OKT3, which preferentially stained the medullary thymocytes. The fraction of OKT3‐ and OKT6‐positive cells increased gradually during fetal life. At 24 weeks of gestation about half of the medullary thymocytes were stained by OKT3 and nearly all the cortical thymocytes were stained by OKT6. The fraction of cells stained with OKT4 and OKT8 was maximal at 14–20 weeks of gestation and decreased slightly with increasing age. The preference for either cortex or medulla of cells possessing the various antigens was less pronounced in fetal life than in infancy and childhood. An anti‐T‐cell antiserum produced in rabbit stained most thymocytes at 10 weeks of gestation. The staining intensity increased gradually until 17 weeks of gestation and then remained constant.