Human lung CD8+ T cells compared with paired non-naive peripheral blood CD8+ T cells

It is unknown whether human lung T cells recirculate or belong to a distinct tissue-specific population. This issue is important for understanding their role in protection against viral infection and their contribution to pathophysiology of lung diseases such as chronic obstructive pulmonary disease. By comparing transcriptional profiles of blood and lung CD8+ T cells, we aimed to reveal specific traits of lung CD8+ T cells. A total of 12 samples was analyzed: 10 patient samples (including 1 technical replicate) and 2 reference samples (including 1 technical replicate). Per patient (in total 3 patients), 3 paired samples were analyzed. These samples were non-naive peripheral blood CD8+ T cells (CD45R0+CD3+CD8+ T cells), memory-type lung CD8+ T cells (CD45R0+CD27+CD3+CD8+ T cells) and effector-type lung CD8+ T cells (CD45R0+CD27-CD3+CD8+ T cells). The reference population consisted of a mix of naive peripheral blood CD8+ T cells from 5 healthy donors.