Ovarian hormone level alterations during rat post-reproductive life-span influence CD8 + T-cell homeostasis.
Exp Biol Med (Maywood)
; 240(10): 1319-32, 2015 Oct.
Article
en En
| MEDLINE
| ID: mdl-25716018
ABSTRACT
The study examined the putative role of ovarian hormones in shaping of rat peripheral T-cell compartment during post-reproductive period. In 20-month-old rats ovariectomized (Ox) at the very end of reproductive period, thymic output, cellularity and composition of major TCRαß + peripheral blood lymphocyte and splenocyte subsets were analyzed. Ovariectomy led to the enlargement of CD8 + peripheral blood lymphocyte and splenocyte subpopulations. This reflected (i) a more efficient thymic generation of CD8 + cells as indicated by increased number of CD4+CD8 + double positive and the most mature CD4-CD8+TCRαß(high) thymocytes and CD8 + recent thymic emigrants (RTEs) in peripheral blood, but not in the spleen of Ox rats, and (ii) the expansion of CD8 + memory/activated peripheral blood lymphocytes and splenocytes. The latter was consistent with a greater frequency of proliferating cells among freshly isolated memory/activated CD8 + peripheral blood lymphocytes and splenocytes and increased proliferative response of CD8 + splenocytes to stimulation with plate-bound anti-CD3 antibody. The former could be related to the rise in splenic IL-7 and IL-15 mRNA expression. Although ovariectomy affected the overall number of CD4 + T cells in none of the examined compartments, it increased CD4+FoxP3 + peripheral blood lymphocyte and splenocyte counts by enhancing their generation in periphery. Collectively, the results suggest that ovariectomy-induced long-lasting disturbances in ovarian hormone levels (mirrored in diminished progesterone serum level in 20-month-old rats) affects both thymic CD8 + cell generation and peripheral homeostasis and leads to the expansion of CD4+FoxP3 + cells in the periphery, thereby enhancing autoreactive cell control on account of immune system efficacy to combat infections and tumors.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Ovario
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Progesterona
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Linfocitos T CD4-Positivos
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Linfocitos T CD8-positivos
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Estrógenos
Límite:
Animals
Idioma:
En
Revista:
Exp Biol Med (Maywood)
Asunto de la revista:
BIOLOGIA
/
FISIOLOGIA
/
MEDICINA
Año:
2015
Tipo del documento:
Article