Correlation between micronutrients and cellular immune responses after CoronaVac vaccination in elderly people

Background: Elderly individuals are often at risk for deficiencies in micronutrients like zinc (Zn) and magnesium (Mg), which are essential for cellular function and immune system homeostasis. Vaccination is a crucial strategy to prevent disease, but micronutrient deficiencies may diminish vaccine effectiveness. The immune response consists of cellular and humoral components, with neopterin serving as a marker for cellular immune activity. Objective: This study aimed to determine whether Zn or Mg deficiencies affect the decrease of cellular immunity between six and 24 weeks after vaccination. Method: This study was a prospective cohort involving eighty-eight elderly individuals (aged 60 and older) who received two doses of the CoronaVac vaccine. Blood samples were collected at six and 24 weeks post-vaccination to measure serum zinc (Zn) and magnesium (Mg) levels using inductively coupled plasma mass spectrometry (ICP-MS). The immune response was assessed by the decrease in serum neopterin levels at six and 24 weeks after vaccination, measured using an enzyme-linked immunoassay (ELISA). Result: There was a positive correlation between Mg and a decrease in neopterin between six and 24 weeks after vaccination, with p = 0.011 and r = -0.296. However, we did not find a correlation between Zn and neopterin levels. This study showed that the lower the Mg levels, the faster the cellular immune response after vaccination disappeared. Nevertheless, the role of Zn in cellular immune response after vaccination is still unclear. Conclusion: Mg deficiency, but not Zn, was correlated with a more rapid reduction of cellular immune response after vaccination.