Henríquez Claudio, Perez Barbara, Morales Natalia, Sarmiento José, Carrasco Cristian, Morán Gabriel, Folch Hugo
Immunology Department, Faculty of Medicine, Universidad Austral de Chile , Valdivia, Chile; Graduate School Faculty of Veterinary Sciences, Universidad Austral de Chile , Valdivia, Chile.
Pharmacology and Morphophysiology Department, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile.
Vet Immunol Immunopathol. 2014 Apr 15;158(3-4):128-34. doi: 10.1016/j.vetimm.2013.12.005. Epub 2014 Jan 7.
Recurrent airway obstruction (RAO) is an equine immune-mediated disease with a high incidence worldwide. The aim of this work was to contribute to the understanding of RAO pathogenesis by studying T cells bearing regulatory markers in peripheral blood (PB) and in bronchoalveolar lavage fluid (BALF) recovered from the same group of susceptible horses before and after exposure to moldy hay, which has been shown to induce RAO signology in our horse herd. With this purpose, mononuclear cells were obtained from the BALF and PB from horses before and after antigenic challenge and were stained with fluorochrome-conjugated antibodies against CD4, CD25 and Foxp3 and subsequently analyzed by flow cytometry. The results indicated that the percentage of CD4+, Foxp3+ cells clearly increased in PB and BALF obtained from horses with RAO. In addition, the percentage of CD4+, CD25(high) cells was greatly augmented in BALF of RAO positive horses compared with a baseline. No changes were observed in the PB compartment. The percentage of CD4+, CD25(high), Foxp3+ cells in BALF increased in horses with active disease compared to horses in remission; this cell population also does not show changes in the PB compartment when RAO positive and RAO negative horses were compared. On the other hand, when the percentage of CD4, Foxp3 positive cells were compared with the percentage of CD4+, CD25(high) cells, the numbers were very similar. This observation was true for PB and BALF cells from non exposed horses as well as horses exposed to antigen. In all the experimental situations studied, the population expressing all of the markers CD4+, CD25(high), Foxp3+ represent only a minor percentage of CD4+, CD25(high) or CD4+, Foxp3 subpopulations; therefore, an significant number of CD4+, CD25(high), Foxp3- and CD4+, CD25(null), Foxp3+ cells must exist. Finally, we conclude that horses with RAO show an airway accumulation of T cells bearing regulatory markers that probably are modulating the course of this disease, and that these T cells may be involved in the resolution of immune-mediated bronchial inflammation.
复发性气道阻塞（RAO）是一种在全球范围内发病率较高的马属动物免疫介导性疾病。本研究的目的是通过研究同一组易感马匹在接触发霉干草前后外周血（PB）和支气管肺泡灌洗液（BALF）中带有调节性标志物的T细胞，来促进对RAO发病机制的理解，发霉干草已被证明能在我们的马群中诱发RAO症状。为此，在抗原刺激前后从马匹的BALF和PB中获取单核细胞，并用荧光染料偶联的抗CD4、CD25和Foxp3抗体进行染色，随后通过流式细胞术进行分析。结果表明，从患有RAO的马匹获得的PB和BALF中，CD4+、Foxp3+细胞的百分比明显增加。此外，与基线相比，RAO阳性马匹的BALF中CD4+、CD25（高表达）细胞的百分比大幅增加。在PB部分未观察到变化。与缓解期马匹相比，患有活动性疾病的马匹BALF中CD4+、CD25（高表达）、Foxp3+细胞的百分比增加；在比较RAO阳性和RAO阴性马匹时，该细胞群体在PB部分也未显示出变化。另一方面，当将CD4、Foxp3阳性细胞的百分比与CD4+、CD25（高表达）细胞的百分比进行比较时，数量非常相似。对于未接触抗原的马匹以及接触抗原的马匹的PB和BALF细胞，这一观察结果均成立。在所有研究的实验情况下，表达所有标志物CD4+、CD25（高表达）、Foxp3+的细胞群体仅占CD4+、CD25（高表达）或CD4+、Foxp3亚群的一小部分；因此，必然存在大量CD4+、CD25（高表达）、Foxp3-和CD4+、CD25（无表达）、Foxp3+细胞。最后，我们得出结论，患有RAO的马匹气道中存在带有调节性标志物的T细胞积聚，这些T细胞可能在调节该疾病的进程，并且这些T细胞可能参与免疫介导的支气管炎症的消退。
