AUTHOR=Frascaroli Giada , Rossini Giada , Maltoni Virginia , Bartoletti Michele , Ortolani Patrizia , Gredmark-Russ Sara , Gelsomino Francesco , Moroni Alessandra , Silenzi Silvia , Castellani Gastone , Sambri Vittorio , Mastroianni Antonio , Brune Wolfram , Varani Stefania
TITLE=Genetic and Functional Characterization of Toll-Like Receptor Responses in Immunocompetent Patients With CMV Mononucleosis
JOURNAL=Frontiers in Cellular and Infection Microbiology
VOLUME=10
YEAR=2020
URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2020.00386
DOI=10.3389/fcimb.2020.00386
ISSN=2235-2988
ABSTRACT=Background: Human cytomegalovirus (CMV) modulates both innate and adaptive immune responses. However, limited data are available on the role of receptors of innate immunity, such as toll-like receptors (TLRs) in contributing to antiviral responses and inflammation.
Objectives: The aim of this translational study was to characterize TLR responses in immunocompetent patients with primary and symptomatic CMV infection.
Study Design: The study population consisted of 40 patients suffering from CMV mononucleosis and 124 blood donors included as controls. We evaluated the association between TLR2, 3, 4, 7 and 9 gene single nucleotide polymorphism (SNP) and susceptibility to symptomatic CMV infection in immunocompetent adults. Additionally, functional TLR-mediated cytokine responses in supernatants of short-term cultures of whole blood from patients with CMV mononucleosis and blood donors were evaluated.
Results: TLR2 and TLR7/8 responses were altered in CMV infected patients as compared to healthy donors and were associated with the release of higher levels of the pro-inflammatory cytokines IL-6 and TNF-α, but not of the anti-inflammatory mediator IL-10. The analysis on the TLR SNPs indicated no difference between patients with CMV infection and the control group.
Conclusions: No variation in the TLR2,3,4,7 and 9 genes was associated to the development of symptomatic CMV infection in immunocompetent adults. Nevertheless, TLR-mediated responses in CMV-infected patients appeared to be skewed toward a pro-inflammatory profile, which may contribute to the development of inflammatory symptoms during the CMV mononucleotic syndrome.