All participants received BNT162b2 (Pfizer-BioNTech) mRNA vaccine, which was well tolerated with no serious AEFI (Adverse events following immunization) was observed. According to the measured HbA1c status, 5 participants (26.32%) with type 2 diabetic had good (<7.0%) glycemic control and 14 (73.68%) had inadequate or poor (\(\ge\)7.0%) glycemic control. The mean of HbA1c was 6.3±0.45 (SD) in type 2 diabetic participants with good glycemic control and 9.27±1.77 (SD) in type 2 diabetic participants with inadequate or poor glycemic control. Participants of the healthy control group had a mean HbA1c of 5.74±0.294 (SD). All participants of both groups were found seroconverted at 4weeks after 1st dose of vaccination.
Comparisons of IFN-\(\gamma\) and IL-2 secreting PBMCs counts from ex-vivo ELISpot assay in type 2 diabetic participants and healthy control showed significant differences (p <0.001) in the repeated measures of both IFN-\(\gamma\) and IL-2 secreting PBMCs counts in both type 2 diabetic and healthy control groups with time. A significant difference (p =0.021) was also observed in the IFN-\(\gamma\) spot counts between T2DM group and control group at 4 weeks after 1st dose (T2).