We established a model to recognize the baseline elements predicting post-vaccine antibody titers using univariate and multivariate linear regression analyses. Results Two thousand fifteen people (median age group 37-year-old, 64.3% female) were signed up for this study, which 10 had a past history of COVID-19. (p?=?0.037) were defined as elements predicting decrease antibody titers after vaccination, whereas previous COVID-19 (p? ?0.001), feminine (p? ?0.001), time taken between 2 dosages (p? ?0.001), and medicine for allergy (p?=?0.024) were defined as elements predicting higher serum antibody titers. Conclusions Our data demonstrate that health care employees have great antibody replies towards the BNT162b2 mRNA COVID-19 vaccine universally. The predictive factors identified inside our study will help optimize the vaccination strategy. strong course=”kwd-title” Keywords: COVID-19, Vaccine, Immunogenicity, Health care worker, SARS-CoV-2 Launch BNT162b2 mRNA vaccine against COVID-19 shows promising efficiency both in a scientific trial [1] and in countrywide mass vaccination configurations [2]. The vaccine in addition has proven short-term efficacy within a large-scale potential cohort study concentrating on healthcare employees, a population that needs to be prioritized for vaccination Phellodendrine chloride [3]; nevertheless, the elements that predict the potency of BNT162b2 mRNA vaccine never have been completely explored. As the humoral replies have been proven to play important assignments in the security against as well as the success from SARS-CoV-2 an infection [[4], [5], [6]], the antibody position after vaccination can offer important info to anticipate long-term effectiveness also to optimize the vaccination technique. However, antibody replies after vaccination have already been assessed just in small-scale studies [[7], [8], [9], [10], [11], [12]]. Here, we report the antibody responses and their predictive factors in 2015 healthcare workers Phellodendrine chloride who received the BNT162b2 mRNA COVID-19 vaccine. Methods We recruited healthcare workers in Chiba University Hospital who were receiving the BNT162b2 mRNA COVID-19 vaccine (Pfizer, Inc., and BioNTech) at the Chiba University Hospital COVID-19 Vaccine Center. Background information was collected by a web-based questionnaire. We considered that a subject had a history of COVID-19 when 1) the subject answered so in the web questionnaire and 2) the subject had been registered as a PCR-positive case in the hospital registry. Blood samples were obtained 0-2?weeks before the 1st dose and 2-5?weeks after the 2nd dose of vaccination. Antibody responses were analyzed Phellodendrine chloride using Elecsys? Anti-SARS-CoV-2S on Cobas 8000 e801 module (Roche Diagnostics, Rotkreuz, Switzerland). This system allows for the quantitative detection of antibodies, predominantly IgG, aiming at the SARS-CoV-2 spike protein receptor-binding domain name. The measurement threshold is usually??0.4 U/mL, and values??0.8 U/mL are considered positive. Samples with a titer 250 U/mL were diluted x10 at a time until the titer became 250 U/mL according to the manufacturer’s protocol. We first performed univariate linear regression analyses to identify factors associated with the serum anti-SARS-CoV-2S antibody titer after vaccination. We next performed a multivariate linear regression analysis with a stepwise method using factors that showed a p-value 0.1 in univariate analyses. Statistical analyses were performed using SPSS version 23.0 (IBM, Armonk, NY). A two-sided p-value 0.05 was considered statistically significant. The study procedures for sample collection and those for analyses were approved by Chiba University Ethics Committee on February 24th, 2021 (No. HS202101-03) and April 21st, 2021 (No. HS202104-01), respectively. All study subjects gave written informed consent before undergoing any study procedures. Results Out of 2838 employees in Chiba University Hospital, 2549 (89.8%) received at least one dose of BNT162b2 mRNA COVID-19 vaccine (30 g) from March 3rd to April 9th, 2021, and 2015 individuals (71.0%) were enrolled in this study. Demographics and background information are summarized in Table?1 . Table?1 Background information and results of univariate/multivariate linear Mouse monoclonal to MBP Tag regression analysis for post-vaccine antibody titer thead th rowspan=”3″ colspan=”1″ Variable /th th colspan=”2″ rowspan=”2″ All (n?=?2015) hr / /th th colspan=”2″ rowspan=”2″ Post-vaccine antibody titer available (n?=?1774) hr / /th th colspan=”4″ rowspan=”1″ Linear regression analysis for post-vaccine antibody titer hr / /th th colspan=”2″ rowspan=”1″ Univariate hr / /th th colspan=”2″ rowspan=”1″ Multivariate hr / /th th rowspan=”1″ colspan=”1″ Data available, n /th th rowspan=”1″ colspan=”1″ Value /th th rowspan=”1″ colspan=”1″ Data available, n /th th rowspan=”1″ colspan=”1″ Value /th th rowspan=”1″ colspan=”1″ Regression coefficients (B) /th th rowspan=”1″ colspan=”1″ 95% confidence interval /th th rowspan=”1″ colspan=”1″ Regression coefficients (B) /th th rowspan=”1″ colspan=”1″ 95% confidence interval /th /thead Age (year-old), median (IQR)201537 (29-47)177439.3?0.016?0.020 C??0.011?0.016?0.021 C??0.012Sex female, n (%)20151296 (64.3)17741168 (65.8)0.3060.200 C 0.4120.2640.156 C 0.372Nationality Japanese, n (%)20152004 (99.5)17741765 (99.5)0.303?0.412 C 1.018Job category201517740.211?0.102???0.320?Nurse672 (33.3)559 (31.5)?Doctor589 (29.2)494 (27.8)?Pharmacist58 (2.9)57 (3.2)?Dentist19 (0.9)11 (0.6)?Others677 (33.6)653 (36.8)Body mass index category151515120.014?0.097 C 0.124? 18.5150.