Recent advances in CD8+ T cell-based immune therapies for HIV cure

Serum β2-microglobulin level is associated with the survival of HIV-associated diffuse large B-cell lymphoma: a retrospective study from China

HIV-associated diffuse large B-cell lymphoma (DLBCL) is a rare type of lymphoma with poor prognosis. β2-microglobulin (β2-M) is elevated in people living with HIV, but its prognostic significance in HIV-associated DLBCL remains unclear. We retrospectively analyzed 89 HIV-associated DLBCL patients treated at Chongqing University Cancer Hospital between October 2012 and December 2023. The primary outcome was the clinical overall survival (OS) rate. The optimal cut-off value of β2-M was determined to be 5 mg/L. Compared to the low serum β2-M group (< 5 mg/L), patients in the high serum β2-M group (≥ 5 mg/L) had a higher International Prognostic Index (IPI)/ age adjusted IPI (aaIPI) score, more B symptoms, lower CD4+T cell counts, and higher lactate dehydrogenase (LDH) level. Patients in high group exhibited poorer OS, with 1-, 3-, and 5-year OS rates of 33.4%, 22.8%, and 18.2%, respectively. Multivariate Cox regression analysis identified serum β2-M ≥ 5 mg/L as an independent risk factor influencing OS of this patient group. Moreover, CD8+T cell count < 392 cells/µL, LDH ≥ 375 U/L, and non-receipt of standard treatment were also independent risk factors. Receiver operating characteristic curve analysis demonstrated that these four independent risk factors accurately predicted survival in HIV-associated DLBCL. 5 mg/L threshold for serum β2-M was associated with poor OS in HIV-associated DLBCL, indicating it could serve as a novel biomarker for assessing their prognosis.

Interventions during Early Infection: Opening a Window for an HIV Cure?

Although combination antiretroviral therapy (ART) has been a landmark achievement for the treatment of human immunodeficiency virus (HIV), an HIV cure has remained elusive. Elimination of latent HIV reservoirs that persist throughout HIV infection is the most challenging barrier to an HIV cure. The progressive HIV infection is marked by the increasing size and diversity of latent HIV reservoirs until an effective immune response is mobilized, which can control but not eliminate HIV infection. The stalemate between HIV replication and the immune response is manifested by the establishment of a viral set point. ART initiation during the early stage limits HIV reservoir development, preserves immune function, improves the quality of life, and may lead to ART-free viral remission in a few people living with HIV (PLWH). However, for the overwhelming majority of PLWH, early ART initiation alone does not cure HIV, and lifelong ART is needed to sustain viral suppression. A critical area of research is focused on determining whether HIV could be functionally cured if additional treatments are provided alongside early ART. Several HIV interventions including Block and Lock, Shock and Kill, broadly neutralizing antibody (bNAb) therapy, adoptive CD8+ T cell therapy, and gene therapy have demonstrated delayed viral rebound and/or viral remission in animal models and/or some PLWH. Whether or not their application during early infection can improve the success of HIV remission is less studied. Herein, we review the current state of clinical and investigative HIV interventions and discuss their potential to improve the likelihood of post-treatment remission if initiated during early infection.

Bridging the gap with multispecific immune cell engagers in cancer and infectious diseases

By binding to multiple antigens simultaneously, multispecific antibodies are expected to substantially improve both the activity and long-term efficacy of antibody-based immunotherapy. Immune cell engagers, a subclass of antibody-based constructs, consist of engineered structures designed to bridge immune effector cells to their target, thereby redirecting the immune response toward the tumor cells or infected cells. The increasing number of recent clinical trials evaluating immune cell engagers reflects the important role of these molecules in new therapeutic approaches for cancer and infections. In this review, we discuss how different immune cell types (T and natural killer lymphocytes, as well as myeloid cells) can be bound by immune cell engagers in immunotherapy for cancer and infectious diseases. Furthermore, we explore the preclinical and clinical advancements of these constructs, and we discuss the challenges in translating the current knowledge from cancer to the virology field. Finally, we speculate on the promising future directions that immune cell engagers may take in cancer treatment and antiviral therapy.