Antibody Production and Immunoglobulin Class in IgG-Deficient Chickens

Abstract

Clinically healthy adult chickens, accompanied by immuno-deficiency, were found in the breeding stock of White Leghorn in our laboratory (Line BK, _??_, 2 chickens) and in a flock of White Leghorn in a poultry farm (_??_, 1 chicken). In these chickens, serum immunoglobulin class and specific antibody production were examined. The results obtained were as follows: 1) By the methods of immunoelectrophoresis and single radial immunodiffusion using anti-chicken γ chain antibody, it was found that serum IgG was negative in a chicken (No. 1) among the breeding stock in our laboratory and in a chicken (No. 2) of the farm cases, and was remarkably low level in another chicken (No. 3) in our laboratory. However, in such serum IgG-deficient chickens, serum 19s-IgM was found to be remarkably high levels of concentration by immunoelectrophoresis using anti-chicken μ chain antibody. 2) In order to investigate the production of the specific IgG antibody, the immuno-deficient chicken (No. 1) was immunized with bovine serum albumin (BSA). However, the precipitin titer of anti-BSA IgG antibody was negative in the No. 1 chicken serum. In order to investigate the production of the specific IgM antibody, the No. 1 chicken and normal chicken were immunized with sheep red blood cell (SRBC). In the results, the aggulutinin titer of anti-SRBC IgM antibody was much higher in the No. 1 chickenn serum than in the normal chicken serum. 3) Serum immunoglobulin classes in 6 cases (2 months of age) of F1 chicks (normal chicken _??_×No.1 chicken _??_) were investigated. It was found that serum IgG was negative in one chick, remarkably low level in two chicks and normal level in three chicks, using specific anti-chicken γ chain antibody. From the results, it is suggested that there are some certain defects in progress of differentiation and maturation of immunologically competent cells in the IgG-negative chickens, and that the immunodeficiency syndrome in the chickens may be a hereditary disorder.