The role of H-2-linked genes in helper T-cell function. I. In vitro expression in B cells of immune response genes controlling helper T-cell activity

Abstract

The ability of murine helper T cells primed to the antigen, sheep erythrocytes (SRBC) to cross-react with burro erythrocytes (BRBC) in the in vitro anti-trinitrophenol (TNP) response to TNP-RBC was shown to be under genetic control. Although non-H-2 genes were shown to influence the absolute level of helper activity assayed after SRBC priming, the extent of cross-reaction of SRBC-primed helpers with BRBC was shown to be controlled by an H-2-1inked Ir gene(s). H-2 haplotypes were identified which determined high, intermediate, or low response to the cross- reacting determinants and the gene(s) controlling the cross-reaction tentatively mapped to the K through I-E end of the H-2 complex. Helpers primed in F(1) mice of high x intermediate or high x low responder parents were tested for cross-reaction using B cells and macrophages (Mφ) of parental haplotypes. In each case the extent of cross-reaction was predicted by the H-2 haplotype of the B cells and Mφ, establishing the expression of the Ir gene(s) in B cells and/or Mφ a t least, but not ruling out its expression in T cells as well. The low cross-reaction seen when T cells from F(1) mice of high × low responder parents were tested on low responder B cells and Mφ was not increased by the presence of high responder Mφ, indicating the Ir gene(s) is expressed in the B cell a t least although it may be expressed in Mφ as well. These and our previously reported experiments are consistent with the hypothesis that helper T cells recognize antigen bound to the surface of B cells and Mφ in association with the product(s) of Ir gene(s) expressed on the B cell and Mφ.

The role of H-2-linked genes in helper T-cell function. VI. Expression of Ir genes by helper T cells.

“…There are a number of possible explanations for the expression of lr genes in helper T cells. Many experiments from this (7,(9)(10)(11) and other (8,15,16) laboratories have shown that/r-genes are expressed in B cells and Mth in a manner consistent with the idea that these genes control the recognition of B-cell-or Mth-bound antigen by T cells. By analogy, it may be, as suggested by Zinkernagel et al (17) and von Boehmer et al (5), that/r-genes, expressed in helper T cells, control the recognition of helper T-cell-bound antigen by a second T cell whose activity is required for the response of the helper T cell.…”

“…Anti-TNP PFC were assayed from triplicate cultures using the slide modification of the hemolytic plaque assay (10). Parallel determinations were made with HRBC and TNP-HRBC and the difference recorded as the number of anti-TNP specific PFC.…”

“…B cells and M~ were prepared free of T cells by injection of donor animals with 0.04 ml ATS i.p. 2 d before transfer, and treatment of combined splenic and peritoneal cells with anti-T serum and complement (10) immediately before transfer. This is a procedure which we have shown in the past supplies antigen-presenting cells of the required haplotype to parental --* F1 chimeric mice (1).…”

“…T cells were isolated from nylon fiber columns as previously described (10). Where necessary these cells were depleted of BI0 or (B10 X B10.M)Ft cells by treatment with B10.A anti-B10 serum followed by washing and incubation with rabbit complement (1).…”

“…Erythrocytes were removed from splenic T-cell preparations before antiserum and complement treatment using modified Gey's solution (14). B cells and Mq~ were obtained from the spleens of TNP-LPS-primed mice by treatment with anti-T-cell serum and complement (10). M4~ for presentation of TNP-(TG)-A--L were obtained from the peritoneal washings of normal mice, and pulsed with TNP-(TG)-A--L as previously described (11).…”