Increased Production of B-Cell Activating Cytokines and Altered Peripheral B-Cell Subset Distribution during HIV-Related Classical Hodgkin Lymphoma.

Abstract

Simple SummaryPatients with HIV are at high risk of developing Hodgkin’s lymphoma. This is potentially due to alterations in blood circulating B-lymphocytes and their activating cytokines. We analyzed the distribution of circulating B-lymphocytes and the level of the activating cytokines IL6, IL10 and BAFF in 38 patients with HIV-related Hodgkin’s lymphoma during a 2-year follow-up. We also compared their characteristics at diagnosis with (1) pre-diagnosis serum samples and (2) samples from control HIV-infected subjects without lymphoma. We found an increase in activating cytokines in cases compared to controls. The level of activating cytokines increased in advanced lymphoma. It decreased over time during follow-up. B-lymphocytic count was similar between patients and controls, but their subset distribution differed. There was an overrepresentation of naive B-lymphocytes over memory B-lymphocytes in HIV-associated Hodgkin lymphoma patients, more pronounced in those with advanced lymphoma. Follow-up showed an increase in B-lymphocytic count with an even greater proportion of naive B-cells. Together this suggests that in HIV-infected patients, Hodgkin lymphoma is associated with an altered blood distribution of B-lymphocytic subsets and an increased production of activating cytokines. This environment may contribute to the process of tumorigenesis.Classical Hodgkin Lymphoma incidence increases in HIV-1-infected patients (HIV-cHL). HIV infection is associated with higher B-cell activation. Here, in 38 HIV-cHL patients from the French cohort ANRS-CO16 Lymphovir, we examined longitudinally over 24 months the serum levels of the B-cell activating cytokines IL10, IL6, and BAFF, and blood distribution of B-cell subsets. Fourteen HIV-cHL patients were also compared to matched HIV-infected controls without cHL. IL10, IL6, and BAFF levels were higher in HIV-cHL patients than in controls (p < 0.0001, p = 0.002, and p < 0.0001, respectively). Cytokine levels increased in patients with advanced-stage lymphoma compared to those with limited-stage (p = 0.002, p = 0.03, and p = 0.01, respectively). Cytokine levels significantly decreased following HIV-cHL diagnosis and treatment. Blood counts of whole B-cells were similar in HIV-cHL patients and controls, but the distribution of B-cell subsets was different with higher ratios of naive B-cells over memory B-cells in HIV-cHL patients. Blood accumulation of naive B-cells was more marked in patients with advanced cHL stages (p = 0.06). During the follow-up, total B-cell counts increased (p < 0.0001), and the proportion of naive B-cells increased further (p = 0.04). Together the results suggest that in HIV-infected patients, cHL is associated with a particular B-cell-related environment that includes increased production of B-cell-activating cytokines and altered peripheral distribution of B-cell subsets. This B-cell-related environment may fuel the process of tumorigenesis.