CD45RA expression of gamma delta and alpha beta T cells emigrating from the fetal and postnatal thymus.
We have compared the expression of CD45RA on alpha beta and gamma delta T cells emigrating from the fetal and postnatal thymus. The fetal and postnatal thymus export both CD45RA+ and CD45RA- T cells. The number of gamma delta +CD45RA+ T cells was remarkably constant regardless of stage of ontogeny or T cell maturity. Around 5-8% of gamma delta thymic emigrants, thymocytes and peripheral blood lymphocytes expressed CD45RA in both fetal and postnatal animals. In contrast to gamma delta T cells, up to one quarter of both fetal and postnatal alpha beta emigrants expressed CD45RA. Post-thymic maturation of CD45RA expression of alpha beta emigrants, which occurred both before and after birth, appeared to be antigen independent.
Department of Veterinary Science, University of Melbourne.
D A
DA
Witherden
N J
NJ
Abernethy
W G
WG
Kimpton
R N
RN
Cahill
D000818:Animals; D000911:Antibodies, Monoclonal; D002465:Cell Movement; D005314:Embryonic and Fetal Development / Q000276:immunology; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D017493:Leukocyte Common Antigens / Q000096:biosynthesis*; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D012756:Sheep; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology* / Q000196:embryology / Q000254:growth & development
D000911:Antibodies, Monoclonal; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D017493:Leukocyte Common Antigens