Graft-versus-host response in sex-linked dwarf, autosomal dwarf and control K strain chickens.

Two independent experiments were conducted to examine the ability of 1) the autosomal-dwarf (ADW) strain and 2) the sex-linked (SLD) strain chicken to make a Graft-versus-Host (GvH) response. In each experiment the GvH response of the dwarf strain was compared to the GvH response of a normal growing control strain, the Cornell K strain chicken. All 3 strains were homozygous B15/B15 at the major histocompatibility complex. GvH responsiveness of peripheral blood lymphocytes (PBL) from females of each strain was assessed at various intervals from 1.5 to 20 months of age using the chorio-allantoic membrane (CAM) assay. The GvH response in female chickens from the ADW strain was significantly higher than in K strain females after the birds had reached sexual maturity (after 5.5 months). The GvH response in females from the SLD strain was, however, significantly lower than in the K strain females throughout the experiment. All strains tended to have a biphasic GvH response. There was a significant increase in GvH responsiveness from 1.5 to 5.5 months of age in chicks from all strains. In the SLD and K strain chickens, this was followed by a drop in the GvH response until 8.5 months of age. In 16- to 20-month-old SLD and K strain hens, the ability to mount a GvH response returned to levels observed in younger (5.5 months) pullets. The GvH responsiveness of the ADW strain remained at a constant level from 5.5 to 12 months of age. However, a second peak in GvH responsiveness was observed in 16-month-old ADW strain hens. Strain differences in GvH responsiveness may be due to the known hormonal abnormalities in the dwarf strains. The suitability of these dwarf strains for the study of endocrine-immune interrelationships is discussed.