Long-term outcome of lung recipients: The role of CD4+CD25highCD127- treg

The role of CD4+CD25highCD127- Treg cells in solid-organ transplant acceptance has been already studied, and while for kidney and liver an inverse correlation with long term graft survival was found; in lung transplant field, in particular with respect to association or prediction of CLAD, results are still controversial. Our study aims to analyze long term kinetic of CD4+CD25highCD127- Treg cells and test its association to several clinical and pharmacological variables(IS, azithromycin, extracorporeal photo-apheresis, infections, CLAD etc). From jan 2009 to dec 2014, 137 lung transplant recipients were submitted to an immunological follow up (I-FU)(105.9 months (6.7-310.5)). I-FU consisted of a complete peripheral immuno-phenotype inclusive of CD4+CD25highCD127- T cell counts and FOXP3 expression (1943 determinations analyzed). Linear OR regression models for repeated measures were used to test the association between Treg and relevant variables, adjusting for time from Tx. Ordered logistic models for panel data were used to test the association between CLAD onset/progression and Treg in the previous three months. Among the variables significantly associated at peripheral Treg cell counts at bivariate analysis: azathioprine therapy(p=0.03), ECP(p