Immunomodulation Effect of Convalescent Plasma Therapy in Severe-Critical COVID-19 Patients

Introduction: Convalescent plasma therapy (CPT) is an alternative therapy for managing COVID-19, but its use is still controversial. Objective: Analyzing the effectiveness of CPT in modulating immune responses based on SARS-COV-2 anti-spike protein receptor-binding domain (s-RBD) IgG, inflammatory cytokines (IL-6 and IL-4), and mortality in severe-critical COVID-19 patients. Methods: This study was an observational analytical with a prospective cohort design. The number of participants was 39 patients from June to December 2020. The participants received CPT and was tested for blood analysis such as IL-4, IL-6 and s-RBD IgG. The data were taken a day before CPT, 1st day, 2nd day, and 7th day after CPT. The analysis included Friedman, Pearson correlation, and Mann-Whitney test which is significant if p <0.05. Results: The value of participant's s-RBD IgG before CPT was 91.49 (0.43-3074.73) AU/mL and the 7th day post-CPT, s-RBD IgG value of 1169.79 (6.48-5577.91) AU/mL (p <0.001). The IL-4 value before CPT was 1.78 (0.85-5.21) ng/mL and the 7th day post-CPT, IL-4 value of 1.97 (0.87-120.30) ng/mL (p = 0.401). The condition was also found in IL-6 value, in which the IL-4 value participant before CPT was 109.61 (0.73-4701.63) ng/mL and the 7th day post-CPT, IL-6 value of 1.97 (0.87-120.30) ng/mL (p = 0.401). No significant correlation found between increased s-RBD IgG level with increased IL-4 and decreased IL-6 before and after CPT in severe-critical COVID-19 patients (p >0.05). No significant correlation was also found between increased s-RBD IgG levels, IL-4 too, and decreased IL-6 after CPT therapy between deceased and alive patients, both in 1st, 2nd, and 7th days (p >0.05). Conclusion: No correlation between the increase in s-RBD IgG levels and changes in IL-4 and IL-6 levels. Changes in s-RBD IgG, IL-4, and IL-6 levels are not associated with mortality in severe-critical COVID-19 degree post CPT recipients.