Memory T-cell targeted immune response in patients of liver cirrhosis
and immunocompetent recipient of ChAdOx1nCoV-19 Vaccine (Covishield)”
Abstract
Despite the effectiveness of COVID-19 vaccination in reducing the
severity of the disease, the demand for booster is increasing in
vulnerable populations like elderly and immunocompromised individuals
especially with each new wave of COVID-19 in different countries. There
is limited data on the sustained immunity against COVID-19 in patients
with liver cirrhosis. The study was aimed to compare the T-cell and
humoral immune response after one year of ChAdOx1nCoV-19 Vaccine in
patients with liver cirrhosis and healthy health-care workers (HCW).
This was a prospective observational study including 36 HCW,19 liver
cirrhosis patients and 10 unvaccinated individuals. Anti-SARS-CoV-2S
antibody, neutralizing antibody and memory T-cell subsets were evaluated
by ELISA and flow cytometry respectively in all three groups after one
year of initial vaccination. Compared to HCW and unvaccinated
individuals, liver cirrhosis patients had significantly depleted
T-cells, although CD4:CD8+ T-cell ratio was normal. Significant
difference was noted in various memory subsets [effector memory RA (P=
0.141, P= 0.000), effector memory (P= 0.000, P= 0.00), central memory
(P= 0.000, P= 0.00), stem cell memory (P= 0.009, P= 0.08) and naïve (P=
0.000, P= 0.02)] of CD4+T and CD8+T respectively. However, on post-hoc
analysis no difference was noted in the extent of memory T-cells between
cirrhotic patients and HCW. Patients with liver cirrhosis developed
comparable memory T-cells after vaccination which can evoke sustainable
immune response on reinfection. Therefore, additional vaccine doses may
not be necessary for cirrhosis patients.