Human CCL25(C-C motif chemokine 25) ELISA Kit

Androgens have profound effects on T cell homeostasis, including regulation of thymic T lymphopoiesis (thymopoiesis) and production of recent thymic emigrants (RTEs), i. e., immature T cells that derive from the thymus and continue their maturation to mature naive T cells in secondary lymphoid organs. Here we investigated the androgen target cell for effects on thymopoiesis and RTEs in spleen and lymph nodes. Male mice with a general androgen receptor knockout (G-ARKO), T cell-specific (T-ARKO), or epithelial cell-specific (E-ARKO) knockout were examined. G-ARKO mice showed increased thymus weight and increased numbers of thymic T cell progenitors. These effects were not T cell-intrinsic, since T-ARKO mice displayed unaltered thymus weight and thymopoiesis. In line with a role for thymic epithelial cells (TECs), E-ARKO mice showed increased thymus weight and numbers of thymic T cell progenitors. Further, E-ARKO mice had more CD4(+)and CD8(+)T cells in spleen and an increased frequency of RTEs among T cells in spleen and lymph nodes. Depletion of the androgen receptor in epithelial cells was also associated with a small shift in the relative number of cortical (reduced) and medullary (increased) TECs and increased CCL25 staining in the thymic medulla, similar to previous observations in castrated mice. In conclusion, we demonstrate that the thymic epithelium is a target compartment for androgen-mediated regulation of thymopoiesis and consequently the generation of RTEs.

Background: Many infants with atopic dermatitis (AD) are sensitized against food or airborne allergens. The severity of AD, using the SCORAD, seems to correlate with elevated serum levels of TARC/CCL17. Other chemokines, such as CCL20 or CCL25, have been described in the context of allergic inflammation. The aim of this study was to analyze whether chemokine serum levels differ within a cohort of infants suffering from varying severities of AD with or without allergic sensitization. Methods: Chemokine serum levels (CCL8, CCL17, CCL20, CCL25) as well as food and airborne allergen-specific IgE were analyzed in infants with AD. Results: About 60.9% (78/128) infants with AD (median age 8.8 months, 49 (38%) girls and 79 (62%) boys) showed a positive screening test to common food allergens and 26.6% to common airborne allergens. There was a strong correlation between serum levels of CCL17 and SCORAD in food-sensitized infants (r(s) = 0.646, p = <1e-04) and airborne-sensitized infants (r(s) = 0.587, p = 0.00065) in contrast to non-sensitized ones. Moreover, food-sensitized infants showed significantly higher levels of CCL25 compared to non-food-sensitized ones (p = 0.007). Conclusion: The strong correlation between TARC/CCL17 and SCORAD in infants with specific sensitizations may be accounted for by the impaired skin barrier. As TARC/CCL17 has been found mainly in the (inflamed) skin but not in the gut, the detection of significantly higher levels of CCL25, ligand of CCR9, localized primarily in the gastrointestinal tract, suggests its impact on food allergen-induced inflammation processes in food-sensitized infants.