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PubMed1979

Further characterization of the human inducer T cell subset defined by monoclonal antibody.

Evidence is presented that the OKTA+ T cell subset in man, defined by a monoclonal hybridoma antibody, provides help for B lymphocyte differentiation in a PWM driven system. Both B cell proliferation and intracytoplasmic immunoglobulin synthesis are facilitated by OKT4+ and not by OKT4- T cells. Given earlier studies demonstrating that OKT4+ T cells were necessary for generation of T cytotoxic cells and the present study that OKT+ T cells are necessary for the differentiation of B cells, it would appear that the OKT+ population is the major human T helper (inducer) subset.

Animals↗
PubMed1979

Human thymus cells: a study of rosette-forming capacity with unsensitized and sensitized erythrocytes of various species.

Human thymus cells from 117 donors aged 2 months to 15 years, were studied for rosette-forming capacity with unsensitized and sensitized erythrocytes of various species. Viability of the thymus cells at the completion of isolation ranged from 95 to 99%. Over 90% of the total population of thymus cells were identified as T lymphocytes by either standard Es-rosette assay utilizing a 4 degree incubation with preceding centrifugation or T--LCL assay, on the average. Gravity Es-rosette assay high affinity Es-rosette assay, stable Es-rosette assay or active Es-rosette assay for identification of subsets of T lymphocytes indicate that most of the human thymus cells were capable of forming rosettes with unsensitized sheep erythrocytes at higher degrees of temperature with or without preceding centrifugation. Approximately half of the human thymus cells were also capable of forming rosettes with unsensitized allogeneic erythrocytes. Less than 3% of the thymus cells expressed receptors for the Fc portion of IgG (T gamma suppressor cells) whereas less than 1% of thymus cells expressed receptors for the Fc portion of IgM (T mu helper cells), indicating that most of the thymus cells are non-T mu/non T gamma cells. Only 1% or less of the thymus cells were identified as B cells by the SIg assay, the Em-rosette assay or the Ia-like antigen assay. There was no significant difference of any rosette assay between males and females or among various age groups.

Adolescent↗
PubMed1979

The collaboration of T-cell subsets in the mitogenic stimulation of purified B-cell subpopulations.

A highly purified preparation of mouse B cells showed greatly decreased incorporation of [6-3H]-thymidine when stimulated with pokeweed Pa-1 mitogen or bacterial lipopolysaccharide compared with mouse splenic lymphocytes. This decreased stimulation was restored by the addition of purified T cells, but not macrophages. Nylon-adherent T cells exerted this helper activity only toward complement receptor-positive B cells (CR+B cells). whereas the helper activity of nylon-non-adherent T cells was effective only on complement receptor-negative B cells (CR-B cells). Since the helper activity of nylon-adherent T cells was completely abolished by the treatment with anti-Ia antiserum and complement but that of nylon-non-adherent T cells was not, it was assumed that Ia+T cells were helper cells for CR+B cells and Ia-T cells helper cells for CR-B cells. Moreover, these helper activities of both T-cell subsets were mediated by soluble factors, which were effective just before the onset of DNA synthesis of the corresponding B-cell subpopulations.

Animals↗
PubMed1979

Characterization of human T lymphocyte subpopulations (TG and T non G): cytologic examination and cytographic analysis.

Two T lymphocyte subpopulations were separated with an immunological method. In fact recently two T cell subsets with receptors for the Fc of IgM (TM) and of IgG (TG) respectively have been described. We have specifically separated TG and T non G lymphocytes by the rosetting technique. Cytological examination was performed on the two cell fractions: the results are in agreement with that already reported. Cytographic analysis was also carried out confirming the cytologic results. The possible practical implications of these acquisitions and those already applied are discussed.

Cell Separation↗
PubMedDate not supplied

[Involvement of lymphocyte populations in rheumatoid synovial lesions].

T and B lymphocyte proportions have been studied in synovial fluid and peripheral blood from 70 patients with classical or definite rheumatoid arthritis (RA). The results have shown that T-cell numbers assessed by E-rosettes and anti-HTLA antiserum, B-cell numbers detected by membrane immunofluorescence and EAC-rosettes from peripheral blood were similar in RA and in a control group. Conversely, "active" E-rosettes which detected a subset of mature T cells, were decreased in blood and very increased in synovial fluid. Furthermore, the percentages of mononuclear cells bearing a Fc-receptor for IgG (EA-rosettes) were higher in synovial fluid than in RA peripheral blood. These data could be in favour of the cell-mediated immunity in rheumatoid arthritis lesions.

Arthritis, Rheumatoid↗
PubMed1979

Markers of human T cell subsets identified by alloantisera.

Analysis by the indirect fluorescence test followed by fluorescence-activated cell sorter (FACS) analysis has shown that antisera recognizing subsets of human T lymphocytes can be produced by planned immunizations involving HLA-A and HLA-B compatible donors. The reactivity of these antisera against some individuals of a population but not others shows that they recognize a polymorphic cell surface component. The reactive subpopulation largely overlaps with the JRA+ subset, which was previously shown to possess regulatory properties in functional assays. The specificity of the antisera for a T cell subset and the unrelatedness of the anti-B cell activity of the same antisera has been confirmed by two-color fluorescence tests.

Antibody Specificity↗
PubMed1979

Local xenogeneic graft-vs-host reaction: a practical assessment of T cell function among cancer patients.

The local xenogeneic graft-vs-host reaction (XGVHR) was used as a practical bioassay to assess T lymphocyte function and immunocompetence among cancer patients. Positive XGVHR was found in 99.5% of normal donors, 70% of cancer patients with early stage disease, and 30% of cancer patients with metastatic disease (p less than 0.001). A minimum of 4.5 x 10(6) immunocompetent T lymphocytes are necessary in order to elicit a positive XGVHR. Negative reactions among cancer patients are characterized by the lack of edema fluid accumulation and the appearance of the most basophils at the test site. This suggests that insufficient amounts of lymphokines are being released by the incompetent T lymphocytes, whereas the host is capable of mounting a rejection reaction as evidenced by the appearance of the basophils. Preliminary evidence suggests that the immunologic defect detected by the XGVHR cannot be corrected by monocyte depletion. The identification of putative suppressor T cell subsets may bear immunotherapeutic implications in the future.

Animals↗
PubMed1975

Casein-induced experimental amyloidosis. V. The response of lymphoid organs to T and B mitogens.

Functional and morphologic studies were performed on the lymphoid organs of inbred CBA/J mice receiving chronic casein administration. In the spleen, this regimen produces marked reticuloendothelial proliferation between 8 and 16 injections (preamyloid phase) and amyloid deposition between 16 and 24 injections. No amyloid was found in the thymus, lymph nodes, and bone marrow of these animals. Phytohemagglutinin and concanavalin A lymphocyte responses as measured by 3-H-thymidine incorporation were reduced in the spleen and lymph node of preamyloid animals but demonstrated partial recovery during the amyloid phase. Phytohemagglutinin and concanavalin A stimulation of thymic cells was significantly increased during both stages of amyloid induction, although the histologic studies revealed a marked involution of the thymic cortex. Lipopolysaccharide stimulation of spleen cells was normal in preamyloid and amyloid animals whereas in lymph node and bone marrow lipopolysaccharide responses were significantly decreased. The findings suggest a selective removal of subsets of T cell populations in the spleen and thymus and migration of B cells from bone marrow to the spleen during experimental amyloidosis.

Amyloidosis↗
PubMed1976

Immunological activities of rat lymphocytes. I. Mitogenic responses and surface markers of lymphocytes from normal, thymectomized and B rats.

Lymphocytes from the peripheral blood, thoracic duct, spleen and lymph nodes of normal, thymectomized (TX) and thymectomized lethally irradiated marrow reconstituted (TXBM or B rats) Lewis rats were studied for their ability to proliferate in vitro in the presence of Con A or PHA. At the same time the lymphoid tissues of these animals were examined for the presence of B cells or T cells by immunofluorescence staining with antiserums to rat immunoglobulins or rat brain antigens (ARBS), respectively. The specificity of ARBS fort T cells was first established in both cytotoxicity and immunofluoresecnce studies with thymocytes as well as pruified T and B cells. In various lymphoid tissues from TX and B rats, cells carrying brain antigens were found which were unable to respond to Con A and PHA. Thymectomy has a lesser effect on the response to Con A that to PHA; this was particularly true in the thoracic duct where, following thymectomy, lymphocytes continued to respond to Con A but lost their ability to respond to PHA. This suggests that the response to PHA and Con A may belong to different cells' subsets but that the ability to respond to either one of these mitogens may be impaired in cells carrying known T cell markers.

Animals↗
PubMed1977

Ala-1: murine alloantigen of activated lymphocytes. II. T and B effector cells express ala-1.

Ala-1 (activated lymphocyte antigen-1) is a murine alloantigen expressed only on activated peripheral T and B lymphocytes. The presence or absence of Ala-1 on specific functional lymphocyte subsets was determined by treating the relevant cell population with anti-Ala-1 and complement, and assaying for residual functional activity. By this method, Ala-1 was shown to be on in vivo primed killer T cells cytotoxic for allogeneic tumor cells. It was also found on helper T cells generated in vivo to sheep red blood cells, and on IgM and IgG plaque-forming cells (PFC) to sheep red blood cells. In contrast, splenic precursors of helper cells and of IgM PFC to sheep red blood cells were completely resistant to treatment with anti-Ala-1 and complement. These findings indicate that effector cells can be distinguished from their nonactivated precursors by their expression of Ala-1.

Animals↗
PubMed1976

B lymphocyte subpopulations in the mouse spleen. A study of the differentiation pathway using free flow electrophoretically separated subpopulations of direct PFC progenitor cells.

Free-flow electrophoretic separation of mouse spleen cells provides three distinct progenitor cells of direct PFC, showing high, medium and low electrophoretic mobility. All progenitor cells possess surface immunoglobulin and mouse B-lymphocyte specific antigen. The progenitor cells of high electrophoretic mobility show high cycling turnover, a spleen seeking capacity of 16%, provide PFC with a maximum 8 days after transfer and reveal an isometrical increase of the PFC dose response line as a function of the graft size. The progenitor cells of medium electrophoretic mobility are low cycling, 16% home to the spleen, a maximum of PFC is developed eight days after transfer and the PFC dose response line increases allometrically. The progenitor cells of low EPM show low cycling activity, 20% home to the spleen, a maximum of PFC is attained six days after transfer and the PFC dose response line rises isometrically. These results suggest that the electrokinetically different PFC progenitors represent biologically distinct subsets. In double transfer experiments, some evidence was obtained that progenitor cells of low electrophoretic mobility are derived from progenitors of higher electrophoretic mobility. The same observation accounts also for the formation of B lymphocytes of low EPM. Since it seemed likely that the PFC progenitor cells represent virgin cells of a single lineage, the results were discussed in the terms of differentiation pathways of B lymphocytes. A model is considered in which a progenitor of medium electrophoretic mobility provides those of high electrophoretic mobility which after passing a transient cycling stage finally produce mature resting B lymphocytes of low electrophoretic mobility.

Animals↗
PubMed1976

Triggering of human peripheral blood B cells: polyclonal induction and modulation of an in vitro PFC response.

In the present studies we utilized polyclonal activators to analyze the signals required to induce antibody synthesis by subpopulations of human peripheral blood lymphocytes. The in vitro synthesis of antibody directed against sheep erythrocytes was measured by a modification of the Jerne plaque assay. The plaques observed contained central lymphoid cells, could be inhibited by anti-human immunoglobulin, and were strictly dependent on both the addition of complement and viable B lymphocytes actively synthesizing protein. Kinetic analysis showed that the PFC response developed over time during cell culture with peak activity occurring between days 6 and 7. It was found that human peripheral blood B lymphocytes, isolated by Sephadex G-200 anti-Fab column chromatography, were nonspecifically induced by either PWM or soluble products of antigen-activated human T cells to differentiate into PFC. In contrast, unfractionated peripheral blood lymphocytes. Ig- cells isolated from immunoabsorbant columns, and B cells enriched by nylon wool adherence were not triggered to antibody synthesis even in the presence of polyclonal activators. B cells isolated by nylon wool adherence and further fractionated by binding and elution from anti-Fab columns were then readily triggered by PWM to differentiate into PFC. These results suggest that the interaction of human B cells with anti-Fab columns, presumably at the Ig receptor, serves as a signal important in the differentiation events leading to PFC activity. The anti-Fab interaction alone, although critical, was not sufficient to induce the differentiation of precursor cells into PFC since subsequent triggering by antigen-activated T cell supernatants or PWM was required for the development of an optimal PFC response. Additional experimental data demonstrated that the PFC response could be regulated by autologous peripheral Ig- lymphoid cells in vitro. At low concentrations of PWM, Ig- cells consistently augmented the B cell PFC response whereas at high concentrations of PWM, suppression was observed. Depletion of E rosetting cells from the Ig- population eliminated the subset responsible for augmentation but did not eliminate the suppressor cell activity.

Animals↗
PubMed1978

Adherent cell function in murine T lymphocyte antigen recognition. II. Definition of genetically restricted and nonrestricted macrophage functions in T cell proliferation.

The mechanisms by which adherent cells, presumably of mononuclear phagocytic lineage, influence in vitro antigen-specific activation of murine T lymphocytes was examined. Two distinct functions for macrophages could be discerned. One macrophage function is dependent on a soluble factor produced by cultured adherent cells and is most easily studied with complex multideterminant antigens. This factor is neither antigen-specific nor MHC-restricted in its action in that PEC, regardless of haplotype, produce factor in the absence of antigen. A second function, antigen-specific T cell activation, is seen when antigens of more restricted heterogeneity are used, such as those under the control of Ir genes. This latter activity demands identity or partial identity between the antigen-presenting cell and the primed T cell, thus suggesting an additional specific, genetically restricted function for macrophages in in vitro antigen recognition. Whether these adherent cell functions are mediated by all or distinct subsets of cells was not established.

Animals↗
PubMed1979

Human tumor-lymphocyte interaction in vitro. VI. Specificity of primary and secondary autologous lymphocyte-mediated cytotoxicity.

A T-cell-enriched lymphocyte subset of samples from 15 tumor patients was tested for primary cytotoxicity against autologous tumor cell preparations and against 1-3 different allogeneic tumor cell preparations from biopsy material. Allogeneic cytotoxicity occurred in only 1 of 10 patients with autologous reactivity. The lymphocytes of 14 patients were cultured with autologous cells from biopsy material for 6 days. These lymphocytes killed autologous targets, but only 1 patient's lymphocytes were cytotoxic against 1 of the 4 allogeneic tumors tested. Cocultivation with allogeneic cells from biopsy specimens generated cytotoxicity toward the sensitizing allogeneic cells in 3 of 9 test combinations. In 2 of 3 instances the effectors were also active against the autologous tumor cells. Cytotoxicity in primary and secondary tests occurred thus only rarely against allogeneic targets. This indicated either the presence of individual tumor-related antigens on the cells from biopsy material or reflected the histocompatibility restriction of T-cell-mediated cytotoxicity.

Antigens, Neoplasm↗
PubMed1979

Subsets of malignant lymphomas in children related to the cell phenotype.

We studied the lymphomatous cells of 39 children presenting with the classical features of malignant lymphoma. Twenty-two had T lymphoblasts. We could classify these patients into three subsets: The T lymphoblasts from children group 1 displayed antigen(s) shared by a thymocyte subpopulation, had terminal deoxynucleotidyl transferase (TDT), but no affinity for peanut agglutinin (PNA). The T lymphoblasts from children group 2 lacked the thymocyte antigen(s), had no TDT, but showed affinity for PNA. The T lymphoblasts from children group 3 displayed mature T-cell antigens, had no TDT, and no affinity for PNA. Children from the three groups were similar in terms of clinical presentation, age and sex distribution, and cell morphology; however patients from the three groups might have a different prognosis. Fourteen children had B lymphoblasts that, in half of the cases, had affinity for Helix pomatia agglutinin. Three patients had lymphoblasts lacking specific marker. Two of them had cells displaying an antigen found on common acute lymphoblastic leukemia cells and had TDT.

Adolescent↗
PubMed1979

B-cell subsets responsive to fluorescein-conjugated antigens. III. Differential effect of E. Coli lipopolysaccharide on T-dependent and T-independent responses in vivo.

The effect of E. coli lipopolysaccharide (LPS) on the induction of both hapten-specific immunity and tolerance was studied in an in vivo system utilizing putative T-cell dependent (TD) or T-cell independent (TI) challenge antigens. The administration of LPS 1 day prior to challenge preempted the response of C3D2 mice to a TD antigen (FL-KLH) but had little effect on the response to FL-Ficoll, a TI antigen. LPS did not affect the responsiveness of C3H/HeJ mice, an LPS-unresponsive strain, to either antigen. The reduction of the response to a putative T-dependent antigen by LPS pre-treatment was only temporary since mice challenged 7 days after LPS responded normally in vivo. We also confirmed that LPS administered shortly after a tolerogen prevented FL-specific IgG tolerence induction and produced B-cell priming to a subsequent T-dependent antigenic challenge. LPS, however, did not significantly interfere with tolerance induction in terms of the IgM responce to either challenge antigen. These results suggest that LPS acts either directly or indirectly on a subpopulation of B cells responsive to a TD antigen. Our data further reflect the heterogeneity of B-cell subpopulations responsive to various polyclonal activators.

Animals↗
PubMed1979

Preferential induction of memory T cells for delayed-type hypersensitivity with reduced and alkylated human serum albumin in mice.

Reduction and alkylation of human serum albumin (HSA) resulted in molecular aggregation of the protein. The reduced and alkylated antigen (RA-HSA) was lacking in the ability to induce delayed-type hypersensitivity (DTH) response as well as antibody response to native HSA in mice, although native HSA induced both responses. On the other hand, RA-HSA could stimulate a priming function that accelerated and enhanced the DTH response to native HSA, which, however, failed to stimulate the function. Thus, DTH-related memory activity was dissociated from DTH-related effector activity. The DTH-related memory activity, manifested by the accelerated an enhanced response in RA-HSA-primed mice, could be transferred antigen-specifically by their spleen cells and T-cell enriched fraction, but not by their T-cell depleted spleen cells. The RA-HSA-primed T cells, however, failed to transfer the effector function for DTH response. These results suggested that DTH-related memory T cells belong to different subset(s) of T cells from effector T cells for a DTH response.

Animals↗