Steroid sensitivity of thymocyte subpopulations during intrathymic differentiation. Effects of 17 beta-estradiol and dexamethasone on subsets expressing T cell antigen receptor or IL-2 receptor

• Published in: The Journal of immunology (1950) Vol. 142; no. 10; pp. 3378 - 3383
• Main Authors: Screpanti, I, Morrone, S, Meco, D, Santoni, A, Gulino, A, Paolini, R, Crisanti, A, Mathieson, BJ, Frati, L
• Format: Journal Article
• Language: English
• Published: United States Am Assoc Immnol 15-05-1989
• Subjects: Animals; Antigens, Differentiation, T-Lymphocyte; Cell Differentiation - drug effects; Dexamethasone - administration & dosage; Dexamethasone - pharmacology; Estradiol - administration & dosage; Estradiol - pharmacology; Leukocyte Count - drug effects; Male; Mice; Mice, Inbred C57BL; Molecular Weight; Phenotype; Receptors, Antigen, T-Cell - analysis; Receptors, Antigen, T-Cell - drug effects; Receptors, Interleukin-2 - analysis; Receptors, Interleukin-2 - drug effects; T-Lymphocytes - classification; T-Lymphocytes - metabolism; T-Lymphocytes - physiology; Thymus Gland - drug effects; Thymus Gland - metabolism; Thymus Gland - physiology; Time Factors
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.142.10.3378

We have studied the effects of the steroid hormones, 17 beta-estradiol and dexamethasone, on the relative proportion of thymocyte expression of CD4 (L3T4), CD8 (Ly-2), TCR and IL-2R, used to identify different stages of thymocyte differentiation. After short-term in vivo steroid treatment, a significant decrease in the number and proportion of the CD4+/CD8+, double positive subpopulation was observed in parallel with a proportional increase in the percentage of the CD4+/CD8- single positive, of the CD4-/CD8-, double negative and, to a lesser extent, of the CD8+/CD4- subsets. Either steroid treatment increased the proportion of cells expressing either the epsilon-chain of the CD3 complex and/or the beta-chain of the TCR (beta-TCR) (TCR+/CD3+) and the 55 kDa protein of the IL-2R (IL-2R+), related to the increase of CD4+ SP thymocytes and of DN cells, respectively. Furthermore, the increased proportion of CD3+ cells could also be partially related to the increase of both the CD4+ and DN subsets. A decrease of the effect on either DN/IL-2R+ cells or CD4+ SP cells was selectively observed after long-term treatments with 17 beta-estradiol or DEX, respectively. It is concluded that after short-term administration, different steroid hormones mediate a similar selective depletion of DP, TCR-/CD3-, IL2R- cells presumably in an intermediate stage of differentiation. However, either steroid effects evolve differently in long-term treatment schedules, resulting in different effects on early (DN/IL2R+) and late (SP/IL2R-) steps of thymocyte differentiation.