Indirect fluorescent antibody tests for parasitic diseases: III. Conjugate-antigen relationships in the tests for trichinosis and schistosomiasis
Sulzer, A.J.; Kagan, I.G.
American Journal Medicine Technol 33(3): 192-199
Experiments demonstrated inhibition of specific staining in the IFA test for trichinosis is due to residual patient's gamma globulin left in the tube by insufficient washing prior to addition of conjugated antispecies sera. Progressive reduction in inhibition was observed when the sensitized antigen was washed 1, 2, 3, and 4 times. Replacement of the gamma globulin (removed by washing) with crystalline human gamma globulin restored the inhibitory effect. Increasing the concentration of anti-species conjugate compensated to some extent for washing the sensitized antigen. The inhibitory effect of residual sera on specific fluorescence was demonstrated with antisera to Trichinella spiralis from humans, rats, and swine. An identical effect was demonstrated with antisera from patients with schistosomiasis.