Characterization of an antigen from rat male accessory glands.

An isolated soluble antigen involved in the autoimmune response against rat male accessory glands migrated as a double band when it was submitted to analytical disc polyacrylamide gel electrophoresis and as a homogeneous molecular species in SDS electrophoresis. The purified antigen had a molecular weight of approximately 78 K by SDS electrophoresis and 80 K by gel filtration chromatography. The antigen was identified as a protein and displays androgen dependency. The purified fraction was pathogenically active in microgram doses and induced humoral and delayed-type hypersensitivity responses. Besides, lesions were observed in the target organ. The cellular infiltration was located in prostate glands according to the localization of antigen by immunofluorescence findings.