RT Journal Article SR Electronic(1) A1 Bishop, J. O.YR 1963 T1 Immunological Assay of some Immobilizing Antigens of Paramecium aurelia, Variety 1 JF Microbiology, VO 30 IS 2 SP 271 OP 280 DO https://doi.org/10.1099/00221287-30-2-271 PB Microbiology Society, SN 1465-2080, AB SUMMARY: Quantitative methods are described for estimating the activity of antisera against Paramecium aurelia, variety 1, and purified preparations of the immobilizing antigen derived from the organisms. Confirmation was obtained that the relation between the serum concentration and the reciprocal of the immobilization time is approximately linear, for times between 3 and 10 min. Titration of antigen preparations by a method based on inhibition of the immobilization reaction gave somewhat higher values than did titration by a gel-diffusion method. Cross-reactions between antigens controlled by genes at different loci and their various specific antisera were in all cases very small. The cross-reactions between antigens controlled by three genes at the D locus and their antisera varied according to the method used to measure them. Extensive cross-reactions were observed when the antisera were absorbed with heterologous paramecia and when precipitin formation in agar gel was followed. Only slight cross-reactions were observed by two methods based on the immobilization reaction., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-30-2-271