CD4+CD25 high FOXP3+ Regulatory T Cells Correlate with FEV1 in North Indian Children with Cystic Fibrosis

Abstract

Cystic fibrosis (CF) lung disease is characterized by dysregulated inflammatory response in the airways. CD4+CD25+ regulatory T cells play a crucial role in maintaining the immune homeostasis. However their role in the disease pathogenesis of CF remains unexplored. Aim: To determine the percentage of circulating CD4+CD25high, FoxP3+ T cell expression in children with CF and controls. Furthermore to evaluate the relationship between CD4+CD25high, FOXP3 T cell % and the clinical status of the disease (lung function). Methods: CD4+CD25+, intracellular FoxP3 expression in peripheral blood were estimated using flowcytometry in 20 children with CF and 10 healthy controls. Spirometry was carried out according to the standard guidelines. Results: We observed a significant difference in CD4+CD25+T cell% in children with CF (5.2 ± 1.2) versus controls (6.8 ± 1.4, p < 0.05), CD4+CD25highTcell% in CF (1.72 ± 0.36) versus controls (2.59 + 0.42, p < 0.003). Similarly a significant difference was observed in FoxP3 T cell% CF: (60.7 ± 6.19) versus controls (76.8 ± 5.16), p < 0.001. A significant positive correlation between FoxP3 T cell% and FEV1 in children with CF(r = 0.822, p < 0.01) was observed.CD4+CD25high T cell% correlated positively with FEV1 (r = 0.742, p < 0.01). Conclusion: Our findings report the first evidence of a decreased expression of circulating CD4+CD25high FoxP3+ T cells in children with CF. Furthermore circulating CD4+ CD25high, FOXP3+ T cell percentage correlated with FEV1.