Expression of murine Lm-1 locus. Lm-1 determinants on lymphocytes and macrophages, and effects of Lm-1 incompatibility on bone marrow grafts

Normal T splenocytes are able to induce immunoglobulin allotypic suppression in F1 hybrid mice

A chronic suppression of Igh-1b and Igh-3b (IgG2a and IgG2b of b haplotype) allotype expression has been induced by injecting T splenocytes from normal BALB/c or BC8 mice into newborn F1 hybrids of appropriate Igh congenic strains: BALB/c into (BALB/c Igha X CB20 Ighb)F1 and BC8 into (BC8 Igha X C57BL/6 Ighb)F1 or (C57BL/6 X BC8)F1. This suppression does not affect IgM (IgH-6b) or IgA (Igh-2b) expression. When the Ighb haplotype is paternally transmitted, the proportion of T splenocyte recipients showing allotypic suppression increases with time reaching 70% 40 weeks after birth. We also succeeded in inducing this pattern of suppression in 2 out of 13 cases when the Ighb was inherited from the mother. These normal T splenocytes are therefore clearly allotype specific. As Igh-6b production is not affected by the suppression, these T splenocytes are believed to influence B cells more or less committed to Igh-1b or Igh-3b production rather than more precocious Igh-6b (IgM of b haplotype) carrying precursors in the classical IgM-IgG filiation pathway.

Linkage between the porcine genes encoding immunoglobulin heavy-chain allotypes and some serum alpha-protease inhibitors: a conserved linkage in pig, mouse and human

Linkage between the genes coding for immunoglobulin heavy-chain allotypes and some serum alpha-protease inhibitors was demonstrated in pigs by means of segregation data in families. A recombination frequency of about 8% was estimated. This represents evolutionary conservation of an autosomal linkage group as linkage between the homologous loci has previously been reported, in humans and in mice.