Surface Ig on rabbit lymphocytes Rabbit B and T cells are distinct populations

Abstract

Rabbit peripheral blood lymphocytes (PBL) were analyzed by immunofluorescence using anti-T cell conjugates and anti-Fab, anti-a1 allotype, anti-IgM and anti-IgA conjugates. In addition, T cells were demonstrated by rosetting with papain-treated homologous erythrocytes. Control experiments, using acid treatment and incubation at 37 degrees C for 18 h after or without pronase treatment, revealed the endogenous origin of all surface determinants tested. A good correlation was found between results obtained with the two anti-T cell conjugates used and the T rosette test on PBL and on lymphoid cells isolated from various organs. In lymphocytes isolated from peripheral blood and from various lymphoid organs, the percentages of T and B cells were respectively 45 and 38 for PBL, 10 and 46 for bone marrow, 27 and 31 for appendix, 40 and 45 for spleen, 42 and 46 for Peyer's patches, 96 and 0.3 for thymus and 70 and 16 for peripheral lymph nodes. The percentage of "null" cells in lymphocyte populations derived from bone marrow and appendix is rather high. The final percentages of T and B cells in rabbit PBL depend to a significant extent on the method of isolation, especially isolation by Ficoll-Hypaque centrifugation results in a depletion of T cells. Moreover, a rather impure lymphoid cell suspension is obtained. In double incubation experiments, T cells (as defined by T cell antigen(s) or rosette formation) and B cells (Fab-bearing cells) were entirely different subpopulations. Allotypes of the a locus could not be detected on the surface of T cells. The results are discussed with respect to genetic coding of antigen receptors on B and T cells.

Effects of anti‐Ig reagents on T cell functions I. Activation of rabbit T cells by anti‐allotype antibodies

“…Our data are compatible with those of others, who showed, using fluorescence microscopy, that rabbit B and T cells are distinct subpopulations [13,15,[27][28][29][30].…”

Immunoglobulin VH determinants defined by monoclonal antibodies.

“…It has also been reported that (a) the anti-VH 315 antibodies (16) inhibit T cell function in mice (17)(18)(19) and cross-react with antigen-specific, soluble factors of T cells (20, 21) (b) unabsorbed chicken antisera against human V/~ fragments stain by immunofluorescence ~30% of normal T cells (44), and (c) unabsorbed rabbit antibodies against the VH fragments of a human IgG3~ myeloma also show weak reactivity by immunofluorescence with ~20% of normal T cells and may inhibit mixed lymphocyte reactions (45). In contrast, our monoclonal anti-Vn antibodies appear unreactive by immunofluorescence with either surface or cytoplasmic components of both resting and activated T cells, and this is consistent with the results of others using goat anti-VH subgroup antibodies (48), rabbit anti-VH framework antibodies (42), and rabbit VH allotype antibodies (11)(12)(13)(14)(15). Our monoclonal anti-Vn subset antibodies could be valuable reagents in the future analysis of this issue using very sensitive assays of antigen-specific, soluble factors of murine and human T cells.…”

“…One set of goat antibodies specific for each human VH subgroup has been prepared by selective adsorption and was found to be useful in typing secreted and membranebound Ig on B cells (3).Evidence from studies (4-8) using anti-idiotype antibodies has suggested that T cells and their antigen-specific, soluble factors might possess Ig-like idiotypic determinants. VH allotypic determinants have also been demonstrable on rabbit T cells by several groups (9, 10) and not by others (11)(12)(13)(14)(15). Antibodies against VH framework regions of the mouse myeloma protein MOPC-315, which cross-react with other mouse Ig regardless of their antibody specificity, class, subclass, subgroup, or allotype (16), may inhibit T cell function (17)(18)(19) and cross-react with soluble factors ofT cells (20,21).…”

Fc receptors on rabbit lymphocytes Existence of receptors for IgG antibody complexed with antigen; conditions for its detection

“…The content of nonlymphoid cells in isolated rabbit PBL suspensions varies, depending on the isolation procedure [39]. Differentiation of the RFC with respect to their morphological characteristics, and, within the lymphocytes, their T, B or null cell features, is described in the following report [23].…”

“…a) The percentages of EAy RFC, IgM-positive cells (F(ab')2 antiIgM-TRITC [39]) and complement-rosetting leukocytes (RL) [25] were determined in untreated PBL (U), immediately after pronase treatment (P), after incubation (I) during 18 h at 3 7 T , and after pronase treatment followed by 37°C incubation (PI). The percentages are expressed as percentage from the initial values, which varied .…”