Lipopolysaccharide-Binding Protein (LBP) and Inflammatory Biomarkers in SARS-CoV-2 Hospitalized Patients

Background/Objectives: Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic with far-reaching impacts on human activities. Moreover, direct viral damage and uncontrolled inflammation have been proposed as contributing factors to the severity of SARS-CoV-2 disease. Lipopolysaccharide binding protein (LBP) is also well recognized for its capability to trigger and modulate the host's innate immune system by attaching to bacterial substances. Nevertheless, the pandemic has further emphasized the critical role of an effective host immune response in controlling viral infection and highlighted the detrimental effect of immune dysregulation. This study aimed to assess plasma levels of LBP and inflammatory biomarkers in SARS-CoV-2 patients with different malnutrition status and severity levels. Methods: This cross-sectional study was carried out in King Khalid University Hospital in Riyadh from December 2020 to December 2021. A total of 166 SARS-CoV-2 patients were recruited including 80 critical and 86 non-critical patients. Medical history, anthropometrical parameters, disease outcome information, and relevant biochemical parameters were extracted from medical records. Plasma samples were collected to test for LBP and inflammatory cytokines. Finally, nutritional risk was assessed by the Nutrition Risk Screening-2002 (NRS-2002) tool. Results: This cross-sectional study found no significant differences in LBP levels between critical and non-critical SARS-CoV-2 patients. However, LBP levels significantly correlated with IL-10, TNF-α and IL-6/IL-10 levels (Spearman's rho = 0.430, 0.276 and -0.397 respectively; p < 0.001). Conclusions: This study confirmed the elevated inflammatory cytokines in hospitalized SARS-CoV-2 patients and their association with disease severity and malnutrition. These findings may support the mechanism of gut inflammation in order to develop new interventions that lower inflammatory biomarkers, disease severity, and aid in SARS-CoV-2 prevention and management.