Orthopoxvirus-Specific T Cell Responses in Convalescent MPOX Patients.

Orthopoxvirus-specific T cell responses were analyzed in 10 patients who had recovered from MPOX including 7 people with HIV (PWH). Eight participants had detectable virus-specific T cell responses, including a PWH who was not on antiretroviral therapy and a PWH on immunosuppressive therapy. These two participants had robust polyfunctional CD4+ T cell responses to peptides from the 121L vaccinia virus (VACV) protein. T cells from 4 out of 5 HLA-A2 positive participants targeted at least one previously described HLA-A2 restricted VACV epitope, including an epitope targeted by two participants. These results advance our understanding of immunity in convalescent MPOX patients.