CD8+ T-cell receptor recognizing H5N1 hemagglutinin peptides presented on MHC class I (H5N1 HA-specific TCR) (H5N1 HA-specific TCR)

The CD8+ T-cell receptor (TCR) recognizing H5N1 hemagglutinin (HA) peptides presented on MHC class I is a specialized heterodimeric protein complex found on the surface of cytotoxic T lymphocytes (CTLs). This receptor is responsible for the specific recognition of viral antigens derived from the H5N1 subtype of Influenza A virus, which are processed and presented as short peptides by Major Histocompatibility Complex (MHC) class I molecules, such as HLA-A*02:01 (PMID: 39584190). Upon binding to the peptide-MHC complex, the TCR initiates a signaling cascade that leads to T-cell activation, proliferation, and the deployment of cytotoxic mechanisms, including the release of perforins and granzymes to induce apoptosis in infected cells (PMID: 39714185). While the primary focus of influenza vaccines has traditionally been the induction of neutralizing antibodies against the HA globular head, this TCR represents a critical target for developing T-cell-based vaccines and TCR-engineered T-cell (TCR-T) therapies (PMID: 39584190). Such strategies aim to provide broader, heterosubtypic protection against pandemic strains by targeting conserved or specific HA epitopes that may be less susceptible to antigenic drift (Nature Communications 2018). Therapeutic approaches include the use of vaccines like Audenz to induce these specific TCR-bearing T cells or the engineering of T cells with high-affinity TCRs to treat severe H5N1 infections (NIH). However, therapeutic challenges include the potential for viral escape through epitope mutations and the phenomenon of 'original antigenic sin,' where pre-existing memory from seasonal influenza may interfere with the induction of a robust H5N1-specific response (PMID: 39714185). Additionally, the use of engineered T cells carries risks such as cytokine release syndrome and off-target cross-reactivity with self-peptides (Frontiers in Immunology). Monitoring the efficacy of these therapies involves measuring biomarkers like IFN-gamma production and MHC-I tetramer binding (PMID: 39584190). Overall, this TCR is a pivotal element in pandemic preparedness and the quest for a universal influenza vaccine (Nature Communications 2018).

Other names

H5N1 hemagglutinin-specific CD8+ T-cell receptorH5-specific TCRHA-specific CD8+ TCRH5N1 HA-specific CD8+ T-cell receptor

Vaccines induce the expansion of CD8+ T cells expressing this TCR by presenting H5N1 HA peptides on MHC class I; TCR-T therapies involve the adoptive transfer of T cells engineered to express this specific TCR to recognize and kill H5N1-infected cells.