Boosting of Secretory IgA Antibody Responses in Man by Parenteral Cholera Vaccination

Abstract

The occurrence of specific antibodies to Vibrio cholera lipopolysaccharide in serum, milk and saliva of Pakistani women from a very low socioeconomic group was studied before and after a single s.c. cholera vaccination. Before immunization all women had low levels of specific antibodies in serum, primarily of Ig[immunoglobulin]M class, and in many cases cholera IgA antibodies were found in milk and saliva as well, indicating earlier natural exposure. The vaccination consistently induced a marked rise in serum antibody titer, and notably produced significant titer increases in 70% of the milk and in 45% of the saliva samples. Whereas the serum antibodies induced were predominantly of the IgG class, secretory IgA was responsible for most of the titer increase in the secretions. Parenteral cholera vaccination can apparently boost local secretory IgA antibody responses in intestinally primed individuals.