ABSTRACT
Emerging SARS-CoV-2 variants have made COVID-19 convalescents susceptible to re-infection and have raised concern about the efficacy of inactivated vaccination in neutralization against emerging variants and antigen-specific B cell response. To this end, a study on a long-term cohort of 208 participants who have recovered from COVID-19 was conducted, and the participants were followed up at 3.3 (Visit 1), 9.2 (Visit 2), and 18.5 (Visit 3) months after SARS-CoV-2 infection. They were classified into three groups (no-vaccination (n = 54), one-dose (n = 62), and two-dose (n = 92) groups) on the basis of the administration of inactivated vaccination. The neutralizing antibody (NAb) titers against the wild-type virus continued to decrease in the no-vaccination group, but they rose significantly in the one-dose and two-dose groups, with the highest NAb titers being observed in the two-dose group at Visit 3. The NAb titers against the Delta variant for the no-vaccination, one-dose, and two-dose groups decreased by 3.3, 1.9, and 2.3 folds relative to the wild-type virus, respectively, and those against the Omicron variant decreased by 7.0, 4.0, and 3.8 folds, respectively. Similarly, the responses of SARS-CoV-2 RBD-specific B cells and memory B cells were boosted by the second vaccine dose. Results showed that the convalescents benefited from the administration of the inactivated vaccine (one or two doses), which enhanced neutralization against highly mutated SARS-CoV-2 variants and memory B cell responses. Two doses of inactivated vaccine among COVID-19 convalescents are therefore recommended for the prevention of the COVID-19 pandemic, and vaccination guidelines and policies need to be updated.
ABSTRACT
Emerging SARS-CoV-2 variants have made COVID-19 convalescents susceptible to re-infection and have raised concern about the efficacy of inactivated vaccination in neutralization against emerging variants and antigen-specific B cell response. To this end, a study on a long-term cohort of 208 participants who have recovered from COVID-19 was conducted, and the participants were followed up at 3.3 (Visit 1), 9.2 (Visit 2), and 18.5 (Visit 3) months after SARS-CoV-2 infection. They were classified into three groups (no-vaccination (n = 54), one-dose (n = 62), and two-dose (n = 92) groups) on the basis of the administration of inactivated vaccination. The neutralizing antibody (NAb) titers against the wild-type virus continued to decrease in the no-vaccination group, but they rose significantly in the one-dose and two-dose groups, with the highest NAb titers being observed in the two-dose group at Visit 3. The NAb titers against the Delta variant for the no-vaccination, one-dose, and two-dose groups decreased by 3.3, 1.9, and 2.3 folds relative to the wild-type virus, respectively, and those against the Omicron variant decreased by 7.0, 4.0, and 3.8 folds, respectively. Similarly, the responses of SARS-CoV-2 RBD-specific B cells and memory B cells were boosted by the second vaccine dose. Results showed that the convalescents benefited from the administration of the inactivated vaccine (one or two doses), which enhanced neutralization against highly mutated SARS-CoV-2 variants and memory B cell responses. Two doses of inactivated vaccine among COVID-19 convalescents are therefore recommended for the prevention of the COVID-19 pandemic, and vaccination guidelines and policies need to be updated.
ABSTRACT
OBJECTIVE: To study the relationship between the infection of hepatitis B virus (HBV) in gastric mucosa and the syndrome of disharmony between liver and stomach. METHODS: Subjects were divided into 2 groups: 30 patients with chronic hepatitis B (CHB) and the syndrome of disharmony between liver and stomach in hepatitis group, and 30 patients with chronic gastritis and the syndrome of disharmony between liver and stomach in gastritis group. Liver function and the markers of HBV were detected. The contents of HBV-DNA in serum and in gastric mucosa were assayed respectively by fluorescence quantitative polymerase chain reaction (FQ-PCR). RESULTS: (1) The incidence of gastric mucosal lesion in hepatitis group was up to 96.7% (29/30). (2) Scores of the syndrome of disharmony between liver and stomach in hepatitis group were significantly lower than those in gastritis group (P<0.05). The positive rates of HBV-DNA in serum, gastric fundus, body and antrum were 56.7%, 76.7%, 76.7% and 70.0%, respectively. (3) A positive correlation was found not only among the content of HBV-DNA in serum and the contents of HBV-DNA in gastric mucosa (r=0.66-0.94, P<0.01), but also among the contents of HBV-DNA in serum, gastric mucosa and the total score of the syndrome of disharmony between liver and stomach in hepatitis group (r=0.36-0.52, P<0.05). CONCLUSION: The infection of HBV is involved in the syndrome of disharmony between liver and stomach. Gastric mucosal lesion is universal in CHB patients with the syndrome of disharmony between liver and stomach.