Durability and determinants of anti-SARS-CoV-2 spike antibodies following the second and third doses of mRNA COVID-19 vaccine.

Objectives: To examine the differences in durability and its determinants of humoral immunity following 2- and 3-dose COVID-19 vaccination.

Methods: Throughout the pandemic, we evaluated the anti-spike IgG antibody titers of 2- and 3-dose mRNA vaccine recipients over time among the staff of a medical and research center in Tokyo. Linear mixed models were used to estimate trajectories of antibody titers from 14 to 180 days after the last immune-conferred event (vaccination or infection) and compare antibody waning rates across prior infection and vaccination status, and across background factors in infection-naïve participants.

Omicron BA.1 neutralizing antibody response following Delta breakthrough infection compared with booster vaccination of BNT162b2.

Background: Longitudinal data are lacking to compare booster effects of Delta breakthrough infection versus third vaccine dose on neutralizing antibodies (NAb) against Omicron.

Methods: Participants were the staff of a national research and medical institution in Tokyo who attended serological surveys on June 2021 (baseline) and December 2021 (follow-up); in between, the Delta-dominant epidemic occurred. Of 844 participants who were infection-naïve and had received two doses of BNT162b2 at baseline, we identified 11 breakthrough infections during follow-up.

Cumulative and undiagnosed SARS-CoV-2 infection among the staff of a medical research centre in Tokyo after the emergence of variants.

To describe the trend of cumulative incidence of coronavirus disease 19 (COVID-19) and undiagnosed cases over the pandemic through the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants among healthcare workers in Tokyo, we analysed data of repeated serological surveys and in-house COVID-19 registry among the staff of National Center for Global Health and Medicine. Participants were asked to donate venous blood and complete a survey questionnaire about COVID-19 diagnosis and vaccine. Positive serology was defined as being positive on Roche or Abbott assay against SARS-CoV-2 nucleocapsid protein, and cumulative infection was defined as either being seropositive or having a history of COVID-19.

Neutralizing antibodies after three doses of the BNT162b2 vaccine, breakthrough infection, and symptoms during the Omicron-predominant wave.

Objectives: To investigate the role of immunogenicity after the third vaccine dose against Omicron infection and COVID-19-compatible symptoms of infection.

Methods: First, we examined vaccine effectiveness (VE) of the third dose against the second dose during the Omicron wave among the staff at a tertiary hospital in Tokyo. In a case-control study of third vaccine recipients, we compared the preinfection live-virus neutralizing antibodies (NAb) against Omicron between breakthrough cases and their controls who had close contact with patients with COVID-19.

Dyslipidemia and SARS-CoV-2 spike antibody titres after the second and third doses of the BNT162b2 vaccine among healthcare workers in Japan.

Objective: This study aimed to examine the sex-associated differences in the relationship between dyslipidemia and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike immunoglobulin (Ig)G antibodies among BNT162b2 vaccine recipients.

Methods: Participants were staff members (aged 21-75 years) of a medical and research institution who underwent an anti-SARS-CoV-2 spike IgG antibody test after the second (n = 1872) and third doses (n = 1075) of the BNT162b2 vaccine. Dyslipidemia was defined as triglyceride level ≥150 mg/dl, high-density lipoprotein-cholesterol level <40 mg/dl, low-density lipoprotein-cholesterol level ≥140 mg/dl, or lipid-lowering medication use.

Association between γ-Glutamyl Transpeptidase and SARS-CoV-2 Spike Antibody Titers among BNT162b2 Vaccine Recipients.

Background: Increased γ-glutamyl transpeptidase (GGT) levels can deplete plasma glutathione, which in turn impairs immune regulation; however, evidence on GGT levels and post-vaccine immunogenicity is lacking.

Objective: To examine the association between GGT and SARS-CoV-2 spike IgG antibodies.

Methods: Participants were 1479 medical staff (aged 21 to 75 years) who received a SARS-CoV-2 antibody test after their second vaccine and whose GGT levels were measured before the vaccine rollout.

Association of Impaired Fasting Glucose and Diabetes with SARS-CoV-2 Spike Antibody Titers after the BNT162b2 Vaccine among Health Care Workers in a Tertiary Hospital in Japan.

Background: Hyperglycemia can alter the activation of innate and acquired immunity, but epidemiological evidence linking hyperglycemia to post-vaccination immunogenicity is limited. Objective: To examine the association between SARS-CoV-2 spike antibody titers after the COVID-19 vaccine and impaired fasting glucose (IFG) and diabetes. Methods: Participants were 953 health care workers aged 21−75 years who were tested for SARS-CoV-2 spike IgG antibodies and underwent a health checkup two months after their second dose of the BNT162b2 vaccine.

Sex-associated differences between BMI and SARS-CoV-2 antibody titers following the BNT162b2 vaccine.

Objective: This study investigated the sex-associated difference in the impact of obesity on antibody response to a COVID-19 vaccine.

Methods: This study included 2,435 health care workers who received two doses of the BioNTech, Pfizer (BNT162b2) vaccine and participated in a serological survey, during which they were tested for anti-SARS-CoV-2 spike immunoglobin G (IgG) antibodies and asked for information on height, weight, and vaccination history via a questionnaire. Multivariable linear regression analysis was used to estimate the geometric mean titers (GMT) of antibodies for each sex and BMI category.

Coronavirus Disease 2019 (COVID-19) Breakthrough Infection and Post-Vaccination Neutralizing Antibodies Among Healthcare Workers in a Referral Hospital in Tokyo: A Case-Control Matching Study.

Background: While increasing coverage of effective vaccines against coronavirus disease 2019 (COVID-19), emergent variants raise concerns about breakthrough infection. Data are limited, however, whether breakthrough infection during the epidemic of the variant is ascribed to insufficient vaccine-induced immunogenicity.

Methods: We describe incident COVID-19 in relation to the vaccination program among workers of a referral hospital in Tokyo.

Consistency of the results of rapid serological tests for SARS-CoV-2 among healthcare workers in a large national hospital in Tokyo, Japan.

We assessed the consistency of seropositive results of three rapid immunoassays (Kits A, B, and C) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) compared to highly accurate serological tests (Abbott and Roche) among healthcare workers in a hospital in Tokyo. The seroprevalence of SARS-CoV-2 immunoglobulin G was 0.41%, 2.

[Harmonization procedures directed toward clinical trials in laboratory medicine at the National Cancer Center Hospital].

Recent advances in pharmacology and molecular sciences made it possible to develop drugs for patients with various maladies. Frustration has existed concerning the delayed provision of these drugs for routine practices in the clinical field. To correct this problem, the importance of clinical trials is increasing.