Subcutaneous drainage modulates TLR4/MyD88/NF-κB signaling in a murine model of postoperative wound infection following gynecological cancer surgery

Surgical site infection remains a clinically important complication after gynecological oncologic surgery, and the precise molecular consequences of preventive interventions on the wound immune microenvironment remain incompletely understood. We examined whether subcutaneous drainage is associated with altered activation of the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor kappa-B (NF-κB) signaling pathway in a murine model of postoperative wound infection. Female BALB/c mice bearing subcutaneous ID8 ovarian carcinoma tumors underwent simulated surgical resection followed by Staphylococcus aureus wound inoculation and were randomly assigned to four groups: sham surgery control, infection model, drainage intervention, and drainage combined with the TLR4 inhibitor TAK-242. Wound tissues were harvested at postoperative days 3, 7, and 14 for bacterial quantification, inflammatory cytokine profiling by ELISA, histopathological evaluation, Western blot, RT-qPCR, and immunofluorescence analyses of pathway components. Subcutaneous drainage was associated with lower bacterial burden, attenuated TNF-α, IL-1β, and IL-6 concentrations, and improved histopathological and wound healing scores compared with undrained infected wounds. Drainage was accompanied by reduced TLR4 and MyD88 expression at both protein and mRNA levels, preservation of IκBα from degradation, and reduced NF-κB p65 phosphorylation and nuclear translocation, although these measurements were made on bulk tissue and cell-type-resolution evidence is lacking. Exploratory structural equation modeling, interpreted cautiously given the modest sample size, suggested that pathway activation could plausibly mediate a substantial portion of the drainage-injury association; the precise mediated fraction is reported as a tentative estimate rather than a firm quantitative claim. Co-administration of TAK-242 with drainage produced additional pathway suppression (combination index ≈ 0.83), approaching baseline activity levels. Collectively, these findings are consistent with, although they do not by themselves prove, an immunomodulatory contribution of subcutaneous drainage within the wound microenvironment; the implications for gynecological oncology should therefore be framed with appropriate caution pending validation in larger animal systems and in human tissue.