Antibody response declined in all age group recipients: Local Research

Antibody responses declined in all age groups, especially in those below 60 years of age while the T cell responses persisted on individuals who received Sinopharm vaccine as shield to COVID-19, a research conducted by the University of Sri Jayewardenepura (USJ) has revealed.

Head of the Department of Immunology and Molecular Sciences of the Sri Jayawardenapura University Prof. Neelika Malavige tweeted that the research was conducted on the persistence of antibody and T cell responses to the Sinopharm vaccines in Sri Lankan individuals.

"Some 95.07% of individuals had detectable SARS-CoV-2 specific total antibodies, while 60.9% had ACE2R-Ab. 14.3% to 16.7% individuals in the 20 to 39 age groups had detectable antibodies to the RBD of the WT and VOC, while the positivity rates of those over 60 years of age was less than 10%. 14/49 (28.6%) had IFNγ ELISpot responses to overlapping peptides of the spike protein, while memory B cell responses were detected in 9/20 to the S1 recombinant protein. The total antibody levels and ACE2R-Ab declined after 2 to 12 weeks from the second dose, while ex-vivo T cell responses remained unchanged. The decline in ACE2R-Ab levels was significant among the 40 to 59 and over 60 age groups," the research revealed