Development of T lymphocytes in the nasal-associated lymphoid tissue (NALT) from growing Wistar rats.
The aim of the present report was to study the development of several T-lymphocyte subsets in the nasal-associated lymphoid tissue (NALT) of growing Wistar rats. CD5+ and CD4+ lymphocytes gradually increased with age. A predominance of CD8alpha+ over CD4+ T cells was found from 7 to 45 days but from 45 to 60 days of age T helper cells outnumbered the cytotoxic subpopulation. The majority of CD8+ T lymphocytes expressed the heterodimeric isoform. The most relevant findings by immunohistochemistry are: (1) the predominance of TCRgammadelta+ and CD8alpha+ cells at 7 days postpartum over all the other T-cell subpopulations; and (2) that TCRgammadelta+ outnumbered TCRalphabeta+ T cells from 7 to 45 days postpartum whereas alphabeta T cells predominated in 45- and 60-day-old rats. Besides, cytometric studies have shown that the percentages of TCRgammadelta+, CD8alpha+, as well as the population coexpressing both phenotypes (TCRgammadelta+CD8alpha+), were significantly higher in rats at 7 days postpartum when compared to 60 day-old rats. In the present study, the finding of a high number of gammadelta+ and CD8+ T cells early in NALT development may indicate the importance of these subpopulations in the protection of the nasal mucosa in suckling and weaning Wistar rats.
Sosa
Gustavo A
GA
Laboratory of Cellular Immunology, CONICET Faculty of Pharmacy and Biochemistry, Department of Biological Sciences, University of Buenos Aires, Junín 956 5th floor C1113AAD, Buenos Aires, Argentina.
Roux
María E
ME
D000367:Age Factors; D000818:Animals; D018956:CD5 Antigens / Q000032:analysis; D005260:Female; D005434:Flow Cytometry; D007150:Immunohistochemistry; D008221:Lymphoid Tissue / Q000276:immunology*; D008297:Male; D009297:Nasal Mucosa / Q000276:immunology*; D051381:Rats; D017208:Rats, Wistar; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis; D013601:T-Lymphocytes / Q000502:physiology*
D018956:CD5 Antigens; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta