CD31 ⁺ T‐cells express greater VEGF ‐A than CD31 ⁻ coun

Abstract

CD31 ⁺ T‐cells possess angiogenic properties and have been termed angiogenic T‐cells (T _ANG ) and are altered in number with advancing age. We examined circulating T _ANG subsets and VEGF‐A content in young ( n  = 16, 18–30 years) and older ( n  = 16, 50–65 years) males by flow cytometry. Cardiorespiratory fitness ( O ₂ max) was quantified. Circulating IL‐6 and cytomegalovirus (CMV) serostatus were determined by immunoassays. T _ANG contained more VEGF‐A than CD31 ⁻ T‐cells (CD31 ⁺ : 9374 ± 8587 AU vs. CD31 ⁻ : 8722 ± 8149 AU, p  = 0.021), also evident in CD4 ⁺ and CD8 ⁺ subsets. Older adults possessed fewer CD4 ⁺ T _ANG cells as a proportion of total CD4 ⁺ T‐cells than younger adults (young: 35% ± 11%; older: 24% ± 9%, p  = 0.004), and all T _ANG subsets from older adults exhibited higher VEGF‐A content than younger adults (CD3 ⁺ : young: 6081 ± 4001 AU; older: 13426 ± 10,945 AU, p  = 0.019; CD31 ⁺ : young: 6373 ± 3972 AU; older: 15660 ± 12,829 AU, p  = 0.011; CD8 ⁺ : young: 6335 ± 4029 AU; older: 11216 ± 8056 AU, p  = 0.043). T _ANG cells and VEGF‐A expression were not independently associated with CMV serostatus, IL‐6 or O ₂ max. Advancing age is associated with a pathological T _ANG phenotype which may contribute to age‐related inflammation.