The current intersection of the COVID-19 and HIV-1 pandemics, has raised concerns about the risk for poor COVID-19 outcomes particularly in regions like sub-Saharan Africa, disproportionally affected by HIV. DPP4/CD26 has been suggested to be a potential therapeutic target and a biomarker for risk in COVID-19 patients with high risk co-morbidities. We therefore evaluated soluble DPP4 (sDPP4) levels and activity in plasma of 131 HIV-infected and 20 HIV-uninfected South African individuals. Flow cytometry was performed to compare cell surface expression of DPP4/CD26 and activation markers on peripheral blood mononuclear cells of extreme clinical phenotypes. Progressors had lower specific DPP4 activity and lower frequency of CD3⁺ T-cells expressing CD26 than HIV-1 controllers, but more activated CD3⁺CD26⁺ T-cells. The frequency of CD26-expressing T-cells negatively correlated with HLA-DR⁺ and CD38⁺ T-cells. Divergent DPP4/CD26 expression between HIV-1 controllers and progressors may have implications for risk and treatment of COVID-19 in people living with HIV.

当前 COVID-19 和 HIV-1 流行病的交集，引发了人们对 COVID-19 结果不佳的风险的担忧，尤其是在撒哈拉以南非洲等受 HIV 影响尤为严重的地区。DPP4/CD26 被认为是 COVID-19 高危合并症患者的潜在治疗靶点和风险生物标志物。因此，我们评估了 131 名 HIV 感染者和 20 名 HIV 未感染者血浆中的可溶性 DPP4 (sDPP4) 水平和活性。进行流式细胞术以比较 DPP4/CD26 的细胞表面表达和极端临床表型的外周血单核细胞上的激活标志物。与 HIV-1 控制者相比，进展者具有较低的 DPP4 特异性活性和表达 CD26 的 CD3 ⁺ T 细胞频率较低，但激活的 CD3 ⁺CD26 ⁺ T 细胞。表达 CD26 的 T 细胞的频率与 HLA-DR ⁺和 CD38 ⁺ T 细胞呈负相关。HIV-1 控制者和进展者之间不同的 DPP4/CD26 表达可能对 HIV 感染者感染 COVID-19 的风险和治疗有影响。