Background MALT1 is linked with multiple organic dysfunctions, inflammatory storm, and T helper (Th) cell differentiation. Herein, the current study aimed to investigate the correlation of peripheral blood mononuclear cell (PBMC) MALT1 with Th1 cells, Th17 cells, and prognosis of sepsis patients. Methods In general, 78 sepsis patients and 40 health controls (HCs) were enrolled. MALT1 expression was detected in PBMCs from all subjects by RT-qPCR. Besides, Th1 and Th17 cells were measured in PBMCs from sepsis patients by flow cytometry; interleukin 17A (IL-17A) and interferon gamma (IFN-gamma) were determined in serum from sepsis patients by ELISA. Results MALT1 expression was higher in sepsis patients than HCs (p < 0.001). MALT1 expression was positively correlated with Th17 cells (r(s) = 0.291, p = 0.038) and IL-17A (r(s) = 0.383, p = 0.001), but not with Th1 cells (r(s) = 0.204, p = 0.151) or IFN-gamma (r(s) = 0.175, p = 0.125) in sepsis patients. MALT1 expression was positively correlated with APACHE II score (r(s) = 0.275, p = 0.015), C-reactive protein (CRP) (r(s) = 0.257, p = 0.023), and sequential organ failure assessment (SOFA) score (r(s) = 0.306, p = 0.006) (MALT1 expression was positively correlated with SOFA respiratory system score (r(s) = 0.348, p = 0.002), and SOFA liver score (r(s) = 0.260, p = 0.021), but not with SOFA scores in nervous system, cardio vascular system, coagulation, and renal system (all p > 0.05)). MALT1 expression (p = 0.010), Th1 cells (p = 0.010), Th17 cells (p = 0.038), and IL-17A (p = 0.012), except for IFN-gamma (p = 0.102), elevated in sepsis deaths compared with sepsis survivors. Conclusion PBMC MALT1 is highly expressed in sepsis patients with its overexpression associated with multiple organic dysfunctions, elevated Th17 cells, and increased mortality risk.
