Expression of b 4 and b 5 ϰ light chain allotypes by B and pre‐B cells in allotype‐suppressed and neutralized b⁴b⁵ rabbits

Abstract

Expression of b 4 and b 5 x light chain allotypes by B and pre-B cells in allotype-suppressed and neutralized b4b5 rabbits*In previous studies, we described a primitive lymphoid cell found in fetal liver and in the bone marrow of older rabbits which contained cytoplasmic IgM but lacked surface IgM detectable by immunofluorescence. In heterozygous b4b5 rabbits, the pre-B cells in which we could detect these kappa chain allotypes appeared to exhibit allelic exclusion. In the present study, we investigated the effects of allotype suppression and its neutralization on the expression of the b 4 and b 5 allotypes by B and pre-B cells from the spleens and bone marrow of b4b5 rabbits. We found that in young allotypesuppressed rabbits, pre-B cells of the suppressed allotype persist in bone marrow when B cells of the suppressed allotype are absent or severely depleted. The persistence of pre-B cells of the suppressed type supports the view that pre-B cells differ in their responsiveness to external influences such as anti-Ig compared to B lymphocytes. Injection of serum with b 5 immunoglobulin into b4b5 animals suppressed 14-23 days previously for b 5 was followed by the appearance of increased proportions of b 5 B cells in spleen within 24 h. Surviving pre-B cells are a likely source of these rapidly appearing B cells as well as of the B cells bearing surface immunoglobulin of the suppressed allotype which appear during the recovery phase of allotype suppression. IntroductionThe b allotypes of rabbit light chains reflect differences in amino acid sequence of the x. chain constant region which are detectable by serological methods. Although there are extensive differences (20-30%) in amino acid sequence between the four b allotypes (b4, b5, b6, and b9) [l-31, they are inherited as simple Mendelian alleles (reviewed in [4, 51). Normally, a heterozygous animal produces ~t chains of both allelic types although an individual cell produces only one of the two alternative forms [6, 71. If a neonatal rabbit is given an injection of antibodies to a single ~t chain allotype, the result will be a long-lasting suppression of the synthesis of that allotype and a compensatory increase in the production of the alternative b allotype in heterozygotes (e.g. b4bS) or of h chains in homozygotes (e.g. b5b5 or b4b4) (reviewed in [8]). This phenomenon, called allotype suppression, has been intensively studied because of the information it may yield concerning mecha-

Immunofluorescence studies on the expression of VHa allotypes by pre‐B and B cells of homozygous and heterozygous rabbits

“…The results are somewhat different from one study which showed a predominance of b4 over b5 pre-B cells in newborn b4b5 marrow [18], but are in relatively close agreement with another which demonstrated approximately equal numbers of b4' and b.5' pre-B cells in both control and allotype-suppressed newborn b4bS marrow [19]. Of course, "pecking orders" of a and b allotypes may be controlled by totally different regulatory mechanisms.…”

“…In studies employing immunoelectron microscopy [8], various rosetting procedures [9-131 and, in one instance, immunofluorescence [14], a significant proportion of B lymphocytes which appeared to exhibit both alleles of a or b allotypes were detected in heterozygotes. Conversely, other investigators using radioiodination [ 151, combined immunofluorescence and autoradiography [16], direct immunofluorescence [17][18][19], flow microfluorometry [20] and rosetting [21] have reported few if any B lymphocytes which express two a or b allotypes.…”

B Lymphocyte Development in the Rabbit

“…bone marrow of these rabbits (Simons et al, 1979). These data are quite different from those obtained from allotype suppression experinients performed in mice.…”

CD8 tumor-infiltrating lymphocytes are predictive of survival in muscle-invasive urothelial carcinoma

“…Subsequently, other methods such as serologic analysis of recombinant expression libraries and database mining (16)(17)(18) have revealed several families of CTAs. To date, Ͼ44 distinct CTA gene or antigen families, such as MAGE, GAGE, BAGE, and NY-ESO-1, have been identified (19,20), and several CTAs have been used as target antigens in vaccine clinical trials for various types of tumors, including UC (21-25). Our own work has shown that high-grade UC expresses high levels of the CTA NY-ESO-1, and that NY-ESO-1 is capable of eliciting T cell responses in patients (12).…”