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 human immunodeficiency virus (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 2 participants had robust polyfunctional CD4+ T-cell responses to peptides from the 121L vaccinia virus (VACV) protein. T-cells from 4 of 5 HLA-A2-positive participants targeted at least 1 previously described HLA-A2-restricted VACV epitope, including an epitope targeted in 2 participants. These results advance our understanding of immunity in convalescent Mpox patients.

Brief Report: Rebound HIV Viremia With Meningoencephalitis After Antiretroviral Therapy Interruption After Allogeneic Bone Marrow Transplant.

BACKGROUND: Allogeneic bone marrow transplant (alloBMT) in people living with HIV can lead to the undetectable levels of HIV reservoirs in blood, even using highly sensitive assays. However, with antiretroviral therapy (ART) interruption, rebound of HIV viremia occurs. The source of this rebound viremia is of interest in HIV cure strategies. METHODS: Within a trial of alloBMT in individuals with hematologic malignancies and HIV (ClinicalTrials.gov, NCT01836068), one recipient self-interrupted ART after achieving >99.5% host cell replacement in peripheral blood by day 147 and developed severe acute retroviral syndrome with meningoencephalitis at 156 days post alloBMT. We isolated replication-competent HIV using a quantitative viral outgrowth assay at 100 and 25 days before alloBMT and from the same time points before alloBMT for HIV DNA and cell-associated RNA from peripheral blood mononuclear cells and resting memory CD4+ T cells. We isolated HIV RNA in plasma and cerebrospinal fluid (CSF) at viral rebound. We sequenced the RT-region of pol and performed neighbor-joining phylogenetic reconstruction. RESULTS: Phylogenetic analysis revealed an identical viral sequence at both pre-alloBMT time points accounting for 9 of 34 sequences (26%) of the sampled HIV reservoir. This sequence population grouped with viral rebound sequences from plasma and CSF with high sequence homology. DISCUSSION: Despite >99.5% replacement of host cells in peripheral blood, ART interruption led to HIV viral rebound in plasma and CSF. Furthermore, the rebound virus matched replication-competent virus from resting memory CD4+ T cells before alloBMT. This case underscores that HIV-infected recipient cells can persist after alloBMT and that latent replication-competent virus can reestablish infection.

Short Communication: Persistence of HIV After Allogeneic Bone Marrow Transplant in a Dually Infected Individual.

Allogeneic bone marrow transplant (alloBMT) with continuous antiretroviral therapy alone has not been shown to completely eradicate HIV, possibly due to HIV persistence in rare residual host cells or infection of donor cells. Within a trial of alloBMT in individuals with hematological malignancies and HIV (ClinicalTrials.gov, NCT01836068), we measured HIV reservoirs longitudinally using a quantitative viral outgrowth assay. We sequenced the reverse transcriptase region of pol for replication-competent virus and performed maximum-likelihood phylogenetic reconstruction. Replacement of host cells was measured using short-tandem repeats. In one participant who had ≥99.5% donor cell replacement, HIV reservoirs declined from 2.2 infectious units per million to undetectable levels at post-alloBMT time points except for week 64. Sequence analysis revealed dual infection pre-alloBMT. Replication-competent virus isolated at week 64 post-alloBMT was identical to a pre-alloBMT variant. This report provides proof-of-concept that minor replication-competent HIV variants can persist at low levels despite ≥99.5% donor cell engraftment post-alloBMT.