| Abstract: | When incubated in Hanks' Balanced Salt Solution (HBSS), rewashed chicken lymphocytes adhere to glass and plastic. At 25°C the reaction begins within 15 minutes and is essentially complete by 3 hours. This adherence is independent of pH and the genotype of the lymphocyte donor, and is insensitive to temperature. Prior addition of fresh plasma, or various serum proteins, blocks adherence. Fresh plasma has an opposite effect on a second kind of adherence which occurs when specific allo-antibodies are included in the suspending medium. Fresh plasma promotes this adherence, which depends on the pH, the genotype of the donor, and the temperature. This plasma-enhanced adherence is termed “allofixation” because the lymphocytes remain at the surface to which they adhere in the presence of alloantibody. More than 90 percent of the small lymphocytes become fixed and they do so without flattening in the manner of phagocytes. They can be removed by agitation or enzyme action and will readhere if given the opportunity. Allofixation does not impair the graft-versus-host (GVH) activity of small lymphocytes. Allofixation occurs in the presence of appropriate A and B antibodies and the rate of adherence discriminates between some homozygotes and heterozygotes. This is the first evidence that A antigens are present on chicken lymphocytes, which suggests that A antigens may be involved in transplantation immunity. |
