Studies on antigens from timothy pollen

A variety of dialyzable and non-dialyzable fractions from neutral timothy pollen extracts were studied in human and guinea pig RAST inhibition as well as in PCA. Extracted material fragmented by chemical reagents and by hydrolytic enzymes was also included in the study. It was found that some low molecular weight fractions were quite active in PCA and in RAST inhibition. The fragmented materials showed in a number of instances a considerably reduced inhibitory capacity in RAST but remarkably high PCA elicitation. Some of the enzymes did not produce significant modifications detectable by RAST inhibition although the test seems to be very sensitive to antigenic modification. It seems quite certain that a considerable number of antigenic specificities are involved in the clinical sera tested.