alpha-1-Antitrypsin immunoreactivity in islet cells of adult human pancreas.

alpha-1-antitrypsin immunoreactivity was demonstrated by immunofluorescence technique in the peripheral islet cells of all ten normal adult human pancreata examined; normal adult human liver was negative. The specificity of the reactions was confirmed by applying various control tests including absorption of the specific antisera with purified alpha-1-antitrypsin, inhibition and blocking tests and by ensuring the monospecificity of the antisera used. The findings suggest that the pancreatic islet may be an additional source of alpha-1-antitrypsin.