Risk assessment of human cytomegalovirus infection in solid organ transplantation: Insight into CD4+ T cell subsets

Abstract

AbstractHuman cytomegalovirus (HCMV) is a significant risk factor for post‐transplant viral infections in organ transplantation, affecting allograft outcomes. Most current methods attempt to predict HCMV viremia or disease by monitoring virus‐specific T cell immunity. This approach may support physicians in limiting treatment toxicity, overmedication, and cost. T cells play an essential role in acquired immunity for stable and long‐term protection against viruses. As a component of cell‐mediated immunity, heterogeneous CD4+ T cells orchestrate immune responses by involving their different subsets, including T helper 1 (Th1), Th2, Th17, Th22, Th9, T follicular helper (Tfh), and T regulatory (Treg). HCMV affects the frequency and phenotype of CD4+ T cells, changing the composition of their subsets during different infection stages. Hypothetically, defining a panel of HCMV‐specific CD4+ T cell subsets and investigating their profile may help classify at‐risk patients. The early detection could be followed by a personalized treatment. This review discusses the frequency changes of CD4+ T cell subsets post‐transplant and their predictive value during HCMV infection.