The Characteristics of Peripheral Blood Lymphocyte Subsets in HIV-related Diffuse Large B-cell Lymphoma Patients and Their Impact on Treatment Efficacy.

Introduction: Peripheral blood lymphocyte subsets have been shown to influence prognosis in HIV-associated Diffuse Large B-Cell Lymphoma (HIV-DLBCL), a rare and highly aggressive form of non-Hodgkin's lymphoma linked to immunosuppression and abnormal B-cell proliferation. To lay the foundation for individualized therapy based on factors such as CD4+/CD8+ ratio and Treg/NK cell characteristics, this retrospective study was conducted to explore the variations in lymphocyte subset levels.

Methods: Overall, 51 HIV-DLBCL patients, 50 DLBCL patients, and 42 Healthy Donors (HD) were enrolled in the study. Data were extracted from outpatient records and the Hospital Information Management System. SPSS 27.0 software was used for statistical analysis of the data.

Results: Significant differences in lymphocyte subsets were observed between groups. HIVDLBCL patients showed decreased CD4⁺ T cell and regulatory T cell (Treg) counts/percentages compared to DLBCL patients and HD, but increased CD8⁺ T cell counts and percentages, as well as Treg percentages. Age-stratified analysis revealed that older HIV-DLBCL patients had lower CD8⁺ T cell counts, reduced CD3⁺ T cell percentages, and elevated CD56⁺CD16⁺ NK cell proportions compared to their younger counterparts.

Discussion: This study revealed a distinct pattern of immune dysregulation in HIV-DLBCL patients, characterized by CD4⁺ T cell depletion and CD8⁺ T cell expansion, which is consistent with previous studies. Age-related immunosenescence may exacerbate the increased proportion of NK cells and the decline in T-cell function, suggesting a poorer prognosis in elderly patients. However, the lack of association between lymphocyte subsets and chemotherapy efficacy may reflect the broad impact of standard regimens on immune reconstitution. Limitations include the small sample size, absence of functional experiments, and failure to assess the influence of coinfections. Future studies should expand the cohort and integrate multi-omics data to validate these findings.

Conclusion: Patients with HIV-DLBCL have distinctive alterations in peripheral blood lymphocyte subsets, such as a decreased absolute count and percentage of CD4+ T cells, in comparison to individuals with DLBCL. These alterations appear age-related and showed no significant association with prior antiretroviral therapy. The therapeutic effect of chemotherapy for HIV-DLBCL, however, might not be impacted by the low absolute count and percentage of CD4+ T-cells in peripheral blood, as well as whether or not they had previously received antiretroviral therapy.