title: Vitamin A status and the immune response to pneumococcal polysaccharide: effects of age and early stages of retinol deficiency in rats.
abstract: Production of antibodies to pneumococcal polysaccharide from Streptococcus pneumoniae, type III was determined in young rats at different ages and stages of vitamin A deficiency. At 30, 35 and 45 d of age, serum retinol concentrations of vitamin A-depleted rats were 46, 35 and 9%, respectively, of the serum retinol concentrations of pair-fed controls. Specific antibody production was low at 30 d of age for both vitamin A-depleted rats and control rats. Between 30 and 45 d of age, antibody production increased considerably in normal rats; however, the response of vitamin A-depleted rats was only 22% (P less than or equal to 0.001) that of controls at 35 d of age and 8% that of controls (P less than or equal to 0.001) for 45-d-old rats. Lymphocyte populations were examined by flow cytometry. The numbers of immunoglobulin M- and immunoglobulin D-positive cells changed with age, but not as a result of dietary treatment. The numbers of total T cells or helper and suppressor T cell subsets did not differ with age or with vitamin A status. These studies showed that the normal antibody response to pneumococcal polysaccharide develops rapidly after 30 d of age in the rat, that this antibody response is impaired even during the early stages of vitamin A deficiency, and that impaired antibody production does not seem to be accompanied by quantitative differences in splenic lymphocyte populations.
authors.affiliation: Department of Physiology and Biochemistry, Medical College of Pennsylvania, Philadelphia 19129.
authors.forename: A M
authors.initials: AM
authors.lastname: Pasatiempo
authors.forename: C E
authors.initials: CE
authors.lastname: Taylor
authors.forename: A C
authors.initials: AC
authors.lastname: Ross
mesh_terms: D000375:Aging / Q000276:immunology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D001402:B-Lymphocytes / Q000276:immunology; D005434:Flow Cytometry; D007072:Immunoglobulin D / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D007958:Leukocyte Count; D008297:Male; D011135:Polysaccharides, Bacterial / Q000276:immunology*; D051381:Rats; D011917:Rats, Inbred Lew; D013154:Spleen / Q000276:immunology; D013223:Statistics as Topic; D013296:Streptococcus pneumoniae / Q000276:immunology*; D014802:Vitamin A Deficiency / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007072:Immunoglobulin D; D007075:Immunoglobulin M; D011135:Polysaccharides, Bacterial; C026604:pneumococcal polysaccharide, type III