Assessment of COVID‑19 vaccines in building immunity response through the measurement of anti‑spike protein antibodies

The ongoing COVID‑19 crisis, caused by severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) has led to illness and loss of life. The primary strategy to change the course of the pandemic is, through vaccination, against SARS‑CoV‑2. The present cross‑sectional study aimed to assess the effectiveness of Sinopharm and AstraZeneca COVID‑19 vaccines through an assessment of anti‑spike protein antibodies. The rate of antibody response was measured by detecting anti‑spike and neutralizing antibodies against SARS‑CoV‑2 after administering two doses of the vaccines. These antibodies are pivotal indicators of the immune response elicited by vaccines, providing crucial insight into their protective efficacy. The objective was to evaluate the response of the host to the vaccine and determine the necessity of booster doses by examining the longevity and variability of antibody responses post‑vaccination. To achieve this, serum and plasma samples were collected from 197 patients that tested positive for SARS‑CoV‑2, and anti‑spike protein antibody levels were measured at 1 month after receiving the second doses of either of the aforementioned vaccines. The samples were analyzed using the Elecsys anti‑SARS‑CoV‑2 S assay on the cobas e411 analyzer, a quantitative test that detects antibodies to the SARS‑CoV‑2 spike protein receptor binding domain, with results of ≥0.8 U/ml considered positive. The results revealed that 92% of the participants tested positive for anti‑spike proteins, with the AstraZeneca vaccine demonstrating a better response (95.45%; 42 out of 44) compared with the Sinopharm vaccine (89,54%; 137 out of 153), exhibiting positive results for anti‑spike antibodies (>0.8 U/ml).1