Effects of vitamin A deficiency and Newcastle disease virus infection on lymphocyte subpopulations in chicken blood.
The effect of vitamin A deficiency and Newcastle disease virus (NDV)-infection on peripheral blood lymphocytes (PBL) was studied by differential cell counting and flow cytometry. Day-old chickens were fed purified diets containing either marginal or adequate levels of vitamin A and at 26 days of age half of the chickens in each group were infected with NDV. The absolute numbers of PBL and their subpopulations were studied until 10 days after infection. Vitamin A deficiency resulted in significantly lower numbers of PBL throughout the experiment. NDV-infection produced lymphopenia during the first 3 days, followed by a strong increase in PBL numbers after 6 days. Both changes in PBL were less pronounced in vitamin A-deficient birds. For flow cytometric analysis monoclonal antibodies reacting specifically with B-cells or a subpopulation of T-cells were used. Vitamin A-induced lymphopenia could be attributed to a decreased number of PBL, negative for both antibodies, and to the absence of an increase in B-cells which normally occurs at this age. The negative cells are suggested to represent, at least partially, cytotoxic T-cells, which may explain the impaired cytotoxic T-cell-activity found in earlier studies. NDV-induced lymphopenia and subsequent increase of PBL could be attributed to all cell types investigated. However, in vitamin A-deficient birds negative cells did not show these reactions. Therefore, it can be concluded that vitamin A deficiency has a detrimental effect on PBL, negative for both antibodies used, and on the normal growth of the number of B-cells at this age.
Rombout
J H
JH
Department of Experimental Animal Morphology and Cell Biology, Wageningen Agricultural University, Netherlands.
van Rens
B T
BT
Sijtsma
S R
SR
van der Weide
M C
MC
West
C E
CE
D000818:Animals; D000911:Antibodies, Monoclonal; D016175:B-Lymphocyte Subsets / Q000276:immunology*; D002645:Chickens / Q000097:blood / Q000276:immunology*; D004195:Disease Models, Animal; D005260:Female; D005434:Flow Cytometry; D009521:Newcastle Disease / Q000276:immunology*; D011201:Poultry Diseases / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014802:Vitamin A Deficiency / Q000276:immunology / Q000662:veterinary*
D000911:Antibodies, Monoclonal