Search

The balance between T helper type 1 (Th1) and T helper type 2 (Th2) cells is critical for both innate and acquired immune reactions. However, the precise mechanisms of T helper-cell differentiation remain unclear. As an important T-cell activation molecule, CD44 participates in the differentiation of Th1 and Th2 cells. We demonstrated that CD44 variant exon v5 (CD44 v5) is highly expressed by induced human Th2 cells. To investigate the role of the CD44 v5 domain in Th2 cell differentiation, we treated human CD4 + T cells with anti-CD44v5 antibody and observed that the levels of phosphorylated STAT6 and GATA3 and the secretion of interleukin-4 (IL-4) were significantly decreased after the treatment. We also further found that the inhibition of Th2 differentiation was caused by the degradation of the alpha chain of IL-4 receptor (IL-4Rα), the CD44 v5 domain colocalized with IL-4Rα on cell surface and the degradation of IL-4Rα increased after CD44 v5 domain blocking or ablating. Our results indicated that CD44v5 antibody treatment interrupted the interaction between CD44 v5 domain and IL-4Rα, but the CD44 v5 domain blockage would not spoil the colocalization between IL-4R expression and T-cell receptor and the immunological synapse formation; similar results were also found in CD44v5-deficient CD4 + T cells. In conclusion, we revealed the function of the CD44 v5 domain in Th2 cell differentiation; blocking or ablating the CD44 v5 domain could accelerate IL-4Rα degradation and then induce the Th2 cell inhibition., (© 2021 Australian and New Zealand Society for Immunology, Inc. This article has been contributed to by US Government employees and their work is in the public domain in the USA.)

Introduction: Salvia miltiorrhiza is a frequently used herb in traditional Chinese medicine, and tanshinone IIA (Tan IIA) and salvianolic acid B (Sal Acid B) are two major extracts obtained from its dried root. The quality of herbal ingredients can be affected by environmental factors., Objective: To evaluate the quality of wild S. miltiorrhiza and investigate the influence of soil constituents and parameters as well as climatic conditions and factors on the content of Tan IIA and Sal Acid B., Methodology: We collected samples in 12 natural locations in the Dao Di area in China, the area in which S. miltiorrhiza grows, that results in a distinctive higher quality of medicinal materials from the harvested plant. The concentrations of Tan IIA and Sal Acid B were measured by high-performance liquid chromatography (HPLC). Soil total carbon, total nitrogen, available nitrogen, available phosphorus, available potassium, and particle size distribution were determined. We also collected climate data using ArcGIS from the WorldClim database, and correlation tests, redundancy, and regression analyses were conducted to analyse the relationship and cluster the samples according to their chemical profile., Results: The content of Tan IIA and Sal Acid B in most of the samples was significantly different (P < 0.05). Soil available phosphorus was considered as a key factor that influenced the quality of wild S. miltiorrhiza, and we found a significant negative association between the concentration of Tan IIA in roots and soil available phosphorus. Moreover, the accumulation of Tan IIA in S. miltiorrhiza was also significantly associated with precipitation in April, May, and October, maximum temperature in January, and standard deviation of temperature seasonality. There was no significant correlation between the content of Sal Acid B and ecological factors. In addition, samples collected from Mengshan, Hexian, and Lushi locations were rich in Tan IIA and tended to cluster together, whereas samples collected from Longquan and Huoshan locations tended to cluster and were poor in Tan IIA., Conclusion: The Tan IIA content in samples collected from southern Anhui was significantly lower than that in other Dao Di locations. The content of Tan IIA was related more to the soil than the temperature. Compared with Tan IIA, Sal Acid B was less influenced by soil and climate factors. The findings of this study may provide helpful references for quality control of medicinal plants that exert pharmacological effects in humans., (© 2020 John Wiley & Sons, Ltd.)