FIGURE 2.

Changes of B cells in sepsis. B-cell number, phenotype, and effector functions are markedly altered in patients with sepsis and are not consistent across different populations. (A) In adult patients with sepsis, reduced B-cell number, heterogeneous redistribution, and selective depletion of B-cell subsets are common, along with increased depletion-like/immunomodulatory profiles and decreased immunocompetent B cells. These changes eventually lead to impaired B-cell immune responses in sepsis. (B) Unlike in adults, B-cell count and percentage of CD24⁺CD38⁺ Breg cells were significantly increased in neonatal sepsis. (C) Elderly patients with sepsis exhibit increased exhausted B cells and dysfunction such as decreased immunoglobulin production. Abbreviations: Breg: regulatory B cell; CD, cluster of differentiation; Ig, immunoglobulin; PD1, programmed cell death 1; PDL1, programmed cell death 1 ligand 1.