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B Cinader

Publications and source records attributed to B Cinader.

32 records · Page 2Linked to original sources
PubMed1976

Rabbit lymphoid cells. I. T-cell mitogens, cell volume and adherence properties as probes for cellular heterogeneity.

Thymus-derived cell populations were characterized by sedimentation velocity in the Earth's gravitational field, by adherence properties, and in terms of the thymus-specific antigen RTLA. T cells, responding to mitogens, could be shown to be a subpopulation of RTLA-bearing cells and to have a relatively large volume. The size distribution of mitogen-responsive cells from different individuals showed some variation, but in general large spleen cells took up less thymidine per 10(6) cells than did large cells from other lymphoid organs. Upon stimulation with concanavalin A (con A) small popliteal lymph node cells took up more thymidine per 10(6) cells than did small thymus cells. The corresponding small cells of mesenteric lymph node and spleen took up intermediate quantities of thymidine. Thymus-derived cells that were resistant to complement-mediated cell kill with RTLA antiserum showed greater responsiveness to con A than did the original cell preparations. Non-adherent cells incorporated more thymidine when stimulated with phytohaemagglutinin (PHA) than when they were stimulated with con A. Lightly adherent cells were relatively more responsive to con A stimulation and firmly adherent cells were less responsive to both. The findings were discussed in terms of the density of RTLA on the membranes of T cells. In adherence and in sedimentation velocity fractionation, the relative yield of nucleated cells always exceeded the yield of PHA- and con A-responsive cells. The differential separation of mitogen responsive and of co-operating cells were considered as a possible cause of this deficit.

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PubMed1976

Rabbit lymphoid cells. II. Anti-allotype antisera, lipopolysaccharide and other bacterial and fungal mitogens as probes for the identification of B-cell subpopulations.

Removal of adherent cells or complement-mediated killing of rabbit thymus lymphocyte antigen (BTLA) bearing rabbit T lymphocytes did not abolish the responsiveness (increased thymidine incorporation) of lymphoid cells to antibody against immunoglobulin allotype, Nocardia water-soluble mitogen (NWSM), pneumococcal polysaccharide SIII (PPSIII), S. abortus lipopolysaccharide (LPS), lipid A conjugated to bovine serum albumin and a crude preparation containing C polysaccharide from the cell wall of Diplococcus pneumoniae. Isologous and heterologous antisera, directed against different portions of the Ig receptor, differed in their capacity to enhance thymidine incorporation. The difference in mitogenicity of these antisera was discussed in terms of the accessibility of cell-bound immunoglobulin receptor sites. Spleen cells, responsive to anti-allotype (Ab4) antiserum and B-cell mitogens, NWSM and PPSIII, were characterized by velocity sedimentation. The mean volume of NWSM- and PPSIII-responsive cells was larger than that of the cells responsive to anti-allotype antiserum. Fractionation of spleen cells on glass bead columns yielded a population of non-adherent cells which were two to six times as responsive to anti-Ab4 antiserum as the original spleen cell suspension. The responsiveness of peripheral blood lymphocytes to anti-Ab4 antiserum was significantly greater than that of spleen cells. On the other hand, spleen cells were more responsive to PPSIII than were cells from the peripheral blood, the popliteal and the mesenteric lymph nodes.

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PubMed1976

Tumor colony formation by Friend virus-infected cells in immunosuppressed mice.

We have investigated the role of host immunological factors in the formation of "tumor colonies" in the spleens of unirradiated C57BL/6 X C3Hf/Bi FI mice 9 days after i.v. injection of spleen cells from Friend virus (FV)-infected C3Hf/Bi donors. Pretreatment of hosts with antilymphocyte serum (ATS) increased the number of tumor colonies. Pretreatment with formalinized FV-infected cells had the opposite effect, and ATS diminished the inhibitory effect of preimmunization. Cell suspensions from 11 individual FV-infected donors were examined. The suspensions differed with respect to their behavior on transplantation into untreated and ATS-pretreated F1 hybrid hosts. With several suspensions, the number of tumor colonies produced was approximately proportional to the number of cells injected; in all of these, ATS increased the slope of the line relating colony number to cell number. With most of the suspensions, tumor colony-forming efficiencies in untreated hosts strikingly decreased with increasing number of cells injected; ATS induced an increase in the number of tumor colonies and rendered the colony-forming response more nearly proportional to cell number. With two suspensions, few or no colonies developed; pretreatment with ATS had no significant effect. When the 11 cell suspensions were considered together, a proportional relation was found between the magnitude of the ATS effect (i.e., colony number in the presence of ATS minus colony number in the absence of ATS) and the colony-forming efficiency in ATS-treated mice. The ATS effect on the average was equivalent to a 2-fold increase in tumor colony-forming efficiency. We interpret these findings to indicate that two factors interact to determine the number of tumor colonies produced by spleen cells from FV-infected C3H donors in untreated F1 hybrid hosts. One is a property of the FV-infected cell population and includes its frequency of tumor colony-forming units; this factor varies widely among different cell suspensions. The other is a property of the tumor colony-forming units-host interrelationship and includes the vulnerability of tumor colony-forming units to the host immune response elicited by the injected cells; this factor appears to be constant with different cell suspensions. The present results show that the two factors can be dissociated in immunosuppressed hosts.

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PubMed1975

Volume, adherence properties, membrane antigens and mitogen responsiveness of rabbit lymphoid cell subpopulations.

Subpopulations of rabbit spleen cells which respond to T and B mitogens, respectively, can be distinguished by sedimentation velocity in the earth's gravitational field. T cell subpopulations which differed in their responsiveness to Con A and to PHA could be identified by differences in adherence properties and by their sensitivity to complement mediated cell kill with RTLA-antiserum.

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PubMed1975

Blast transformation of rabbit B-derived lymphocytes by a mitogen extracted from Nocardia.

Nocardia water soluble mitogen (NWSM) is known to stimulate mouse and rabbit lymphoid cells and to act selectively on murine B-derived lymphocytes. In this paper, evidence is presented that NWSM is also a mitogen for rabbit bursal equivalent cells and does not bring about blast transformation of thymus-derived rabbit cells. Pretreatment of rabbit spleen lymphocytes with antibody directed against rabbit thymus lymphocyte antigen (anti RTLA serum) and with complement did not affect the strong increase of thymidine incorporation which follows stimulation with NWSM. The mitogen-induced polyclonal activation of antibody-forming cells and resulted in the presence of 30% of cells with the ultrastructural characteristics of plasmocytes. These observations led to the conclusion that NWSM is a mitogen for a B-derived lymphocyte of the rabbit.

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