IL-6R identifies early differentiated human effector memory CD8+ T cells that potently expand and produce IL-2 and IL-13. Homo sapiens

We found a unique subset of effector memory (EM) CD8+ T cells that expressed high levels of IL-6 receptor in human peripheral blood. These cells which also expressed high levels of IL-7Ra (referred to as IL-6R high IL-7Rahigh cells) had the a distinct gene expression profile and cellular characteristics compared to other EM CD8+ T cells. IL-6R high IL-7Ra high cells were early differentiated EM CD8+ T cells with decreased expression of T-bet, KLRG1, perforin and granzyme B. These cells had increased cell proliferation likely secondary to enhanced IL-2 production and high affinity IL-2R expression. IL-6R high IL-7Ra high EM CD8+ T cells exclusively produced high levels of IL-2, IL-5, IL-9 and IL-13 although IFN-r was produced by this cell subset and other EM CD8+ T cells. Of interest, IL-6R high IL-7Ra high EM CD8+ T cells expanded in the peripheral blood of patients with chronic obstructive pulmonary disease (COPD) and asthma where CD8+ T cells, IL-13 and IFN-r are suggested to be involved in the pathogenesis. Being the early-differentiated EM CD8+ T cells with a potent capacity to proliferate, survive and generate multiple cytokines, IL-6R high IL-7Ra high EM CD8+ T cells may serve as a primary reservoir for effector CD8+ T cells which potently expand and produce cytokines upon immune stimulation. Overall design: Duplicate experiments were performed for each condition. In each condition, we independently prepared total RNA using the RNeasy mini kit (Qiagen) and assessed RNA integrity using Bioanalyzer 2100 (Agilent)- RINs were close to 10 for all samples. RNA was then amplified and hybridized to the Illumina HumanHT-12 v4.0 BeadChip, according to Illumina standard protocols.