BackgroundRelatlimab plus nivolumab (anti-lymphocyte-activation gene 3 plus anti-programmed death 1 [anti-LAG-3+anti-PD-1]) has been approved by the FDA as a first-line therapy for stage III/IV melanoma, but its detailed effect on the immune system is unknown.MethodsWe evaluated blood samples from 40 immunotherapy-naive or prior immunotherapy-refractory patients with metastatic melanoma treated with anti-LAG-3+anti-PD-1 in a phase I trial using single-cell RNA and T cell receptor sequencing (scRNA+TCRαβ-Seq) combined with other multiomics profiling.ResultsThe highest LAG3 expression was noted in NK cells, Tregs, and CD8+ T cells, and these cell populations underwent the most significant changes during the treatment. Adaptive NK cells were enriched in responders and underwent profound transcriptomic changes during the therapy, resulting in an active phenotype. LAG3+ Tregs expanded, but based on the transcriptome profile, became metabolically silent during the treatment. Last, higher baseline TCR clonality was observed in responding patients, and their expanding CD8+ T cell clones gained a more cytotoxic and NK-like phenotype.ConclusionAnti-LAG-3+anti-PD-1 therapy has profound effects on NK cells and Tregs in addition to CD8+ T cells.Trial registrationClinicalTrials.gov (NCT01968109)FundingCancer Foundation Finland, Sigrid Juselius Foundation, Signe and Ane Gyllenberg Foundation, Relander Foundation, State funding for university-level health research in Finland, a Helsinki Institute of Life Sciences Fellow grant, Academy of Finland (grant numbers 314442, 311081, 335432, and 335436), and an investigator-initiated research grant from BMS.

In the Children's Oncology Group ANBL1221 phase 2 trial for patients with first relapse/first declaration of refractory high-risk neuroblastoma, irinotecan and temozolomide (I/T) combined with either temsirolimus (TEMS) or immunotherapy (the anti-GD2 antibody dinutuximab (DIN) and granulocyte macrophage colony stimulating factory (GM-CSF)) was administered. The response rate among patients treated with I/T/DIN/GM-CSF in the initial cohort (n=17) was 53%; additional patients were enrolled to permit further evaluation of this chemoimmunotherapy regimen. Potential associations between immune-related biomarkers and clinical outcomes including response and survival were evaluated.
Patients were evaluated for specific immunogenotypes that influence natural killer (NK) cell activity, including killer immunoglobulin-like receptors (KIRs) and their ligands, Fc gamma receptors, and NCR3. Total white cells and leucocyte subsets were assessed via complete blood counts, and flow cytometry of peripheral blood mononuclear cells was performed to assess the potential association between immune cell subpopulations and surface marker expression and clinical outcomes. Appropriate statistical tests of association were performed. The Bonferroni correction for multiple comparisons was performed where indicated.
Of the immunogenotypes assessed, the presence or absence of certain KIR and their ligands was associated with clinical outcomes in patients treated with chemoimmunotherapy rather than I/T/TEMS. While median values of CD161, CD56, and KIR differed in responders and non-responders, statistical significance was not maintained in logistic regression models. White cell and neutrophil counts were associated with differences in survival outcomes, however, increases in risk of event in patients assigned to chemoimmunotherapy were not clinically significant.
These findings are consistent with those of prior studies showing that KIR/KIR-ligand genotypes are associated with clinical outcomes following anti-GD2 immunotherapy in children with neuroblastoma. The current study confirms the importance of KIR/KIR-ligand genotype in the context of I/T/DIN/GM-CSF chemoimmunotherapy administered to patients with relapsed or refractory disease in a clinical trial. These results are important because this regimen is now widely used for treatment of patients at time of first relapse/first declaration of refractory disease. Efforts to assess the role of NK cells and genes that influence their function in response to immunotherapy are ongoing.
NCT01767194.
© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Immune non-responder after highly active antiretroviral therapy (HAART) is the main cause of opportunistic infections and high mortality in AIDS patients, but the mechanism underlying immune reconstitution failure is poorly understood. Here, we performed scRNA-seq, and scATAC-seq analysis of peripheral blood mononuclear cells (PBMCs) derived from immune non-responder (INR) and responder (IR) HIV-1-infected subjects. We found low expression of mucosal-associated invariant T (MAIT) cells in INRs, which exhibited transcriptional profiles associated with impaired mitochondrial function and apoptosis signaling. Single-cell assays for transposase-accessible chromatin (scATAC-seq) and flow cytometry revealed diminished mitochondrial fitness in MAIT cells from INRs, and MAIT had low expression of transcription factor A for mitochondria (TFAM) and peroxisomal proliferator-activated receptor alpha (PPARA). These findings demonstrate that restoring mitochondrial function could modulate the immune dysfunction characteristic of MAIT against bacterial co-infections in INRs subjects.
© 2022. The Author(s).

Immune non-responder (INR) after highly active antiretroviral therapy (HAART) is the main cause of opportunistic infection and high mortality in AIDS patients, but the mechanism underlying immune reconstitution failure is poorly understood. Here we performed scRNA-seq and scATAC-seq analysis of peripheral blood mononuclear cells (PBMCs) derived from Immune nonresponder (INR) and responder (IR) HIV-1-infected subjects. We then describe the mitochondrial function of MAIT by flow cytometry in INRs and IRs. We founded there were diminished frequencies and numbers of MAIT cells in INRs, and MAIT cells from INRs displayed transcriptional profiles associated with the impairment of mitochondrial function and apoptosis signaling. ScATAC-seq and flow cytometry revealed diminished mitochondrial fitness in MAIT cells from INRs, and MAIT had low expression of transcription factor A for mitochondria (TFAM) and PPARA. These findings demonstrate the restoring mitochondrial function could modulate the immune dysfunction characteristic of MAIT, which against bacterial co-infections in INRs subjects.

Innate lymphoid cells (ILC) are lymphoid lineage innate immune cells that do not mount antigen-specific responses due to their lack of B and T-cell receptors. ILCs are predominantly found at mucosal surfaces, as gatekeepers against invading infectious agents through rapid secretion of immune regulatory cytokines. HIV associated destruction of mucosal lymphoid tissue depletes ILCs, among other immune dysfunctions. Studies have described limited restoration of ILCs during the first three years of combined antiretroviral therapy (cART). Little is known about restoration of ILCs during long-term cART, particularly in sub-Saharan Africa which hosts increasing numbers of adults with at least a decade of cART.
We examined phenotypes and function of ILCs from peripheral blood mononuclear cells after 12 years of suppressive cART. We report that ILC1 frequencies (T-BET + CD127 + and CD161 +) were higher in cART-treated HIV-infected relative to age-matched health HIV-negative adults; P = 0.04 whereas ILC precursors (ILCP) were comparable in the two groups (P = 0.56). Interferon gamma (IFN-γ) secretion by ILC1 was higher among cART-treated HIV-infected relative to HIV-negative adults (P = 0.03).
HIV associated alteration of ILC persisted during cART and may likely affect the quality of host innate and adaptive immune responses during long-term cART.
© 2021. The Author(s).