T-cell receptor recognizing Respiratory Syncytial Virus fusion protein peptides in MHC class II (RSV F-specific CD4+ TCR)

The T-cell receptor (TCR) recognizing Respiratory Syncytial Virus (RSV) fusion (F) protein peptides in the context of MHC class II is a fundamental mediator of the adaptive immune response to RSV infection [1: Ruckwardt et al., J. Virol. 2019]. These TCRs, located on CD4+ T helper cells, identify viral peptide fragments presented by Major Histocompatibility Complex (MHC) class II molecules on the surface of professional antigen-presenting cells like dendritic cells [2: Roche et al., Nat. Rev. Immunol. 2017]. Upon binding, the TCR complex triggers intracellular signaling that promotes T-cell proliferation and the secretion of cytokines such as interferon-gamma (IFN-g) and interleukin-2 (IL-2), which are essential for coordinating both cellular and humoral immunity [4: Openo et al., Front. Immunol. 2020]. In the context of RSV pathology, the quality of the TCR-mediated response is critical; while a Th1-biased response is protective, a Th2-biased response has been historically linked to vaccine-enhanced respiratory disease (ERD), characterized by eosinophilic infiltration and airway obstruction [3: Knudson et al., Vaccine 2014; 5: Eichinger et al., Viruses 2019]. Modern vaccines, including Arexvy and Abrysvo, specifically target these receptors by presenting stabilized prefusion F protein antigens to elicit a potent and safe immune memory [6: Kampmann et al., N. Engl. J. Med. 2023]. Consequently, these TCRs serve as vital targets for evaluating vaccine immunogenicity and developing novel T-cell-based therapies for vulnerable populations, such as infants and the elderly.

Other names

RSV F-specific T-cell receptorCD4+ TCR for RSV F proteinMHC class II-restricted RSV F TCRRSV F-specific CD4+ T-cell receptor

The TCR complex recognizes RSV F-derived peptides presented by MHC class II molecules on antigen-presenting cells. This interaction triggers the CD3 signaling cascade, leading to CD4+ T-cell activation, proliferation, and the secretion of Th1-type cytokines (e.g., IFN-gamma) that support viral clearance and B-cell antibody production [1, 4].