Changes In Antibody Titers Research Articles

A follow-up study of 100 patients with acute brucellosis for its prognosis and prevention.

To prevent chronic brucellosis, this study analysed the changes in patient antibody titers, and the trajectories of biochemical indicators at different stages of brucellosis, identified relevant biomarkers, and explored risk factors affecting the prognosis of brucellosis patients. A prospective cohort study was conducted to follow 100 patients with acute brucellosis. Laboratory serological test results [taken with a serum (tube) agglutination test (SAT)] and biochemical parameters (liver function, renal function, and hematological system) were measured repeatedly at four-time points: 0 weeks-baseline survey, 6 weeks after the first treatment, 12 weeks after the second treatment, and 3 months after the third treatment. The changes in the antibody titres and biochemical parameters at each time point were analysed for trend changes. One hundred patients with acute brucellosis were enrolled in this follow-up study, with 100% retention in follow-up. By the third follow-up, 21 patients had turned subacute and 11 had turned chronic. One-way repeated measures analysis of variance results showed statistically significant differences (p < 0.01) across the time points for the following five indicators: alanine aminotransferase, aspartate aminotransferase, total bilirubin, serum creatinine (SCr) and platelet count. The clinical symptoms of patients in the acute stage were mainly joint pain, fatigue, and fever, while those in the chronic stage complained primarily of joint pain and fatigue. The results of multivariate logistic analysis showed that joint pain [odds ratio (OR) = 3.652, 95% confidence interval (CI) =1.379-9.672], monoarticular pain (OR = 6.356, 95% CI = 4.660-8.669), elevated SCr (OR = 15.804, 95% CI = 1.644-151.966) and elevated haemoglobin (Hb) (OR = 1.219, 95% CI = 1.065-1.736) were risk factors for poor prognosis (not cured or chronic) in patients with brucellosis. The trajectory of changes in patient SAT posirates and antibody titers can be used to distinguish patients with chronic brucellosis. The brucellosis is preventable and treatable, and the standard treatment can be effective in reducing the clinical symptoms of affected patients. If patients are not treated in a timely manner, joint pain, monoarticular pain, and elevated SCr are risk factors for patients who are not cured. Therefore, the treatment cycle for these patients should be extended.

Reinfection rates, change in antibody titers and adverse events after COVID-19 vaccination among patients previously infected with COVID-19 in Metro Manila, Philippines: a secondary analysis of a completed cohort study

BackgroundVariation in immune response to COVID-19 vaccines is observed among different ethnicities. We aimed to describe the reinfection rates, change in antibody titers, and adverse events among Filipinos.MethodsThis is a secondary analysis of a cohort study of 307 participants within one year of having COVID-19 infection. We measured COVID-19 antibody levels at pre-determined timepoints (Days 21, 90, 180, 270, and 360 from initial infection). We monitored for COVID-19 symptoms and obtained details on COVID-19 vaccination. An adjudication committee classified the participants as probable, possible, or unlikely COVID-19 reinfection. We determined the probable reinfection rate, adverse events, and the geometric mean titer (GMT) ratio of pre- and post-vaccination antibody levels according to type and brand of COVID-19 vaccine.ResultsAt the end of the follow-up period, 287 (93.5%) out of 307 study participants were fully vaccinated, 1 was partially vaccinated (0.3%), and 19 were unvaccinated (6.2%). Among the fully vaccinated participants, those given mRNA vaccines had the lowest reinfection rate (19.2 cases/100 person-years, 95% CI 9.6, 38.4), followed by viral vector vaccines (29.8 cases/100 person-years, 95% CI 16.9, 52.4). We observed the highest reinfection rate among those given inactivated virus vaccines (32.7 cases/100 person-years, 95% CI 23.6, 45.3). The reinfection rate was 8.6 cases/100 person-years (95% CI 4.1, 17.9) for unvaccinated participants and 3.6 cases/100 person-years (95% CI 0.5, 25.3) for partially vaccinated participants. We observed the largest rise in antibody titers among those given mRNA vaccines (GMT ratio 288.5), and the smallest rise among those given inactivated virus vaccines (GMT ratio 16.7). We observed the highest percentage of adverse events following immunization with viral vector vaccines (63.8%), followed by mRNA vaccines (62.7%), and the lowest for inactivated virus vaccines (34.7%). No serious adverse events were reported.ConclusionVaccinees given the mRNA vaccines had the lowest reinfection rate and the highest rise in antibody titers. Vaccinees given inactivated virus vaccines had the highest reinfection rate, smallest rise in antibody titers, and lowest percentage of adverse events. The small sample size and imbalanced distribution of the type of vaccines received limits the external generalizability of our results.Study RegistrationThe cohort study was registered at the Philippine Health Research Registry on December 14, 2020 (PHRR201214-003199).

The prevalence of post-COVID-19 vaccination syndrome and quality of life among COVID-19-vaccinated individuals

BackgroundThere were many studies conducted to determine how immunization affects people with long-term COVID. The results of those studies have caused debate as they gave rise to varying outcomes. Some evidence indicates a change in, an improvement in, a continuation of, or even a worsening of long-term COVID symptoms following vaccination. The ratio of change in antibody titers was noticeably larger in the group of people whose illnesses became worse. Hence, this study aimed to explore potential post-COVID-19 vaccination syndrome (PCVS) in vaccinated individuals and also to assess their quality of life (QoL). MethodologyBetween September 2021 and May 2023, an ambidirectional, descriptive, follow-up cohort study was conducted, enrolling participants who were 18 years of age or older, met the vaccination requirements established by the Ministry of Health and Family Welfare, Government of India, and had completed the primary immunization series with the AZD1222® or BBV152® vaccine. The prevalence of PCVS and the QoL measured using EQ-5D-5L were assessed at 1 month, 6 months, and 12 months post-COVID-19 vaccination. ResultsAZD1222® vaccine was received by 84.28% (343) of the participants, and BBV152® vaccine was received by 15.72% (64) of the study participants. A month after the primary vaccination series, 52.8% (215) of the total participants had at least 1 PCVS, 39.8% (162) at 6 months, and 64.6% (263) at 12 months. Among those who had received vaccinations, the QoL increased at 6 months to 0.975±0.08 and declined at 12 months to 0.94±0.13 from 0.949±0.13 at 1 month after receiving a primary immunization. The overall prevalence of PCVS between AZD1222®-vaccinated individuals and BBV152®-vaccinated individuals at a month post-vaccination was 54.5% vs. 43.8%, at 6 months it was 41.1% vs. 32.8%, and at 12 months it was 65.59% vs. 59.4%. The QoL between AZD1222®-vaccinated individuals and BBV152®-vaccinated individuals at a month post-vaccination was 0.95±0.13 vs. 0.95±0.126, at 6 months it was 0.98±0.08 vs. 0.97±0.07, and at 12 months it was 0.94±0.12 vs. 0.92±0.20. However, there was no statistically significant difference in the prevalence of PCVS and QoL between AZD1222® and BBV152®-vaccinated individuals.The percentage of participants who had at least one PCVS was 83.9% (146) in the group that got booster doses and 50.2% (117) in the group that did not. The QoL was 0.9±0.15 in the group receiving booster dosages and 0.96±0.11 in the group not receiving them. There was a statistically significant difference in the prevalence of PCVS and QoL between booster dose recipients and no booster dose recipients. ConclusionIn the study, we observed the prevalence of PCVS and was similar to long-term COVID; it declined over time and increased following booster immunization. Contrary to PCVS prevalence, QoL rises with time and falls after booster doses. There is no difference in the prevalence of PCVS and the quality of life among AZD1222® and BBV152®.

Clinical relevance of distinguishing autoimmune nodopathies from CIDP: longitudinal assessment in a large cohort

BackgroundThe aim of this study was to determine treatment response and whether it is associated with antibody titre change in patients with autoimmune nodopathy (AN) previously diagnosed as chronic inflammatory...

Quantitative analysis of protective T cell immunity against brucellosis

The results of study relationship between antigen reactivity of T-lymphocyte population under ex vivo conditions and the intensity of protective post-vaccination immunity to causative agent of brucellosis are presented. Тaking into account the peculiarities of immunopathogenesis brucellosis and prevailing role of adaptive T-cell immunity to protect against the causative agent of infection, possibility predictive evaluation of protective immunity against brucellosis using CAST-tests is considered as the most important aspect of brucellosis problems. There is an obvious need for an ex vivo correlation analysis of the activity of antigen stimulation of T cells and the intensity of protective immunity formed after vaccination. A close direct proportional relationship was established between the number of live microbial cells Brucella abortus 19BA vaccine strain administered and increase in ex vivo CD3-cell activation. A close correlation was revealed between ex vivo value of antigen-induced stimulation CD3-lymphocytes and level of post-vaccination immunological protection against brucellosis infection. It has been shown that in biomodels vaccinated against brucellosis with a T-lymphocyte stimulation coefficient of 50% or more (according to intensity of antigen-induced ex vivo expression CD25), 100% protection from the development of brucellosis infection after infection with Brucella melitensis at a dose of 1 × 103 live microbial cells are provided. At the same time, there was a lack of a close correlation between an increase in the dose of brucella vaccine strain administered to biomodels and a change in geometric mean antibody titer, presence of a weakly pronounced relationship between level of agglutinins and immunological protection of biomodels from development brucellosis infection and indicators bacterial contamination body.Based on results of study, it was demonstrated that it is possible to quantify the formation and protective activity of T-cell immunity to causative agent of brucellosis based on analysis of level antigen reactivity of CD3-lymphocytes ex vivo. The data obtained and described methodological approach can be used as a predictive criterion in assessing protective level of cellular immunity to causative agent of brucellosis in vaccinated or recovering patients, as well as in order to analyze effectiveness of specific prophylaxis brucellosis and study immunogenicity and protective properties candidate for brucellosis vWe present the results of studies related to antigen reactivity of T lymphocyte population under ex vivo conditions and the intensity of protective post-vaccination immunity to causative agent of brucellosis. Due to peculiarities of immunopathogenesis in brucellosis infection and prevailing role of adaptive T cell immunity for protection against the causative agent of infection, a predictive evaluation of protective immunity against brucellosis using CAST-tests is considered the most important issue in the field. There is an obvious need for ex vivo analysis of correlations between the activity of antigen stimulation of T cells, and the intensity of protective immunity raised after vaccination. A close direct relationship was established between the number of live microbial cells of Brucella abortus 19BA vaccine strain administered, and increase in ex vivo CD3 cell activation. A close correlation (r = -0.841 ÷ -0.966, R2 = 0.708 ÷ 0.969) was revealed between ex vivo values of antigeninduced stimulation of CD3 lymphocytes, and the levels of post-vaccination immunological protection against brucellosis infection. We have shown that, in biomodels vaccinated against brucellosis with a T lymphocyte stimulation coefficient of 50% or more (according to intensity of antigen-induced ex vivo CD25 expression), 100% protection against brucellosis infection was achieved after contamination with Brucella melitensis at a dose of 1×103 live microbial cells. At the same time, a lack of a close correlation was noted between an increased dose of Brucella vaccine strain administered to biomodels, and a change in geometric mean of antibody titer (R2 = 0.357÷0.404), along with a weak relationship between the levels of agglutinins and immunological protection of biomodels from developing brucellosis infection and indices of in vivo bacterial contamination.These results suggest an opportunity to quantify development and protective activity of T cell immunity to the causal agent of brucellosis based ex vivo levels of antigen reactivity of CD3 lymphocytes. A correlation analysis between the state of T cell antigen reactivity and immunological resistance to brucellosis infection indicated a high degree of closeness between these indices. The key influence on activity of protective immunity is exerted by the levels of antigen reactivity of T lymphocytes, whereas the quotient of antigenic stimulation in CD3+CD25+ population may be considered the most informative index of immune protective activity. The data obtained and the described methodology may be used as a predictive criterion in assessing protective level of cellular immunity to causative agent of brucellosis in vaccinated or recovering patients, testing the efficiency of specific prophylaxis in brucellosis and studying immunogenicity and protective properties of candidate vaccines against brucellosis.

Decreased rate of blood donors with high ABO antibody titers in Japan and the underlying factors: Comparisons between 2010 and 2021

Background and ObjectivesPreviously (2007), it was reported that ABO antibody titers in Japanese blood donors had decreased significantly compared to 20 years before. Here we evaluated whether further decrease of antibody titers had occurred in recent years, and the potential factors associated with changes in antibody titers. Materials and MethodsSerum/plasma from random blood donors in 2010 and 2021 (2010: 3369, 2021: 5796 donors) was classified into low, middle, and high ABO antibody titers according to the reactivity of diluted serum/plasma (2.5-fold and 20-fold) by an automated microplate system. The rates of low/high titer in the two periods were compared. Logistic regression and age-gender-BMI subgroup analyses were conducted to identify the factors that contributed to changes in antibody titers. ResultsCompared to 2010, the rate of donors with high ABO antibody titers was decreased in 2021 for both anti-A and anti-B (anti-A, 2010: 23.8%, 2021: 19.3%; anti-B, 2010: 23.8%, 2021: 16.4%). In logistic regression analysis, age was found to significantly affect both anti-A and anti-B antibody titers (anti-A, adjusted odds ratio 0.36, 95% CI 0.31–0.41; anti-B, 0.42, 0.37–0.47), and BMI (0.82, 0.73–0.92) and other time-related factors (0.79, 0.71–0.88) significantly affect anti-B antibody titers. Subgroup analysis revealed decreased rate of high anti-B titers in the higher age group in 2021. ConclusionThe rate of high ABO antibody titers, especially high anti-B titers, was significantly decreased in 2021, and our results suggested an association with aging and obesity of blood donors as well as other time-related factors.

Prognostic impact of perioperative change in serum p53 antibody titers in esophageal squamous cell carcinoma.

The clinical effectiveness of tumor markers for estimating prognosis in esophageal squamous cell carcinoma (ESCC) remains unclear. We assessed the clinical impact of changes in perioperative serum p53 antibodies (s-p53-Abs) titers in ESCC. From January 2011 to March 2021, 249 patients were enrolled in this study. Titers of s-p53-Abs were measured before the initial treatment and 3months after esophagectomy. Patients were divided into a s-p53-Abs decreased or unchanged group (Group D, n = 217) and an increased group (Group I, n = 32). Short- and long-term outcomes were compared between the groups. There was no correlation between the changes in squamous cell carcinoma antigen and carcinoembryonic antigen titers and recurrence site, number of recurrent lesions, and prognosis. However, the recurrence rate was significantly higher in Group I than in Group D (53.1% vs. 28.6%, p = 0.008), especially for distant organ recurrence (37.5% vs. 18.4%, p = 0.019). Furthermore, the rate of polyrecurrence was higher in Group I than in Group D (34.4% vs. 14.3%, p = 0.009). Recurrence-free survival (RFS) was significantly worse in Group I than in Group D (median survival time, 21.2months vs. 36.7months, p = 0.015). Multivariate analysis revealed that lymphatic vessel infiltration (hazard ratio [HR], 1.721; 95% CI 1.069-2.772; p = 0.026), blood vessel infiltration (HR, 2.348; 95% CI 1.385-3.982; p = 0.002), advanced pathological stage (≥ III) (HR, 3.937; 95% CI 2.295-6.754; p < 0.001), and increased s-p53-Abs titers (HR, 2.635; 95% CI 1.488-4.667; p = 0.001) were independent predictors of poor RFS. Elevation of s-p53-Abs titers after esophagectomy can predict polyrecurrence in distant organs and poor prognosis.

Changes in antibody titres and comparative efficacy of some unconventional remedies in mitigating the effects of infectious bursal disease virus infection in pullet chicks

Unconventional remedies are used by farmers against infectious bursal disease (IBD). This study assessed changes in IBD antibody titres and efficacy of some unconventional remedies used by farmers against IBD. Day old ISA brown pullets were assigned into eight groups (A-H) and inoculated with a very virulent IBD virus (vvIBDV) at 21 days of age as follows; group A - administered aqueous leaf extract of Kaya senegalensis (KS); B, C, D, E, and F administered remedies designated as SEV, ENP, ASMS, DLP, and OVX, respectively; G, and H were negative, and positive control, respectively. Changes in IBD antibody (Ab) titres, clinical signs, morbidity and mortality rates, gross lesions, weights and organ ratios of bursal (BF), spleen (S) and thymus (T) were assessed. There were protective levels of Ab in groups of chicks at 2 and 7 days of age. SEV and ASMS potentiated Ab response to vvIBDV; SEV mitigated the severity of clinical signs, morbidity and mortality rates, gross lesions and changes in body and BF weights and SBR; KS clinical signs, morbidity and mortality rates, BF weight and BBR; ENP morbidity rate, spleen and thymus weights and TBR; ASMS thymus weight and TBR; DLP gross lesions, BF weight and BBR; OVX body, spleen weights and SBR. The remedies demonstrated varied actions against VVIBDV infection. SEV and KS leaves could be administered at the onset of IBD outbreak and before IBD vaccination. Processing of KS leaves to reduce concentration of antimetabolites is recommended.

Longitudinal Changes in IgG-Type SARS-CoV-2 Antibody Titers after COVID-19 Vaccination and a Prominent Increase in Antibody Titers When Infected after Vaccination.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody titers level and duration of elevated levels are considered important indicators for confirming the efficacy of coronavirus disease 2019 (COVID-19) vaccines. The objective of this study was to demonstrate the changes in antibody titers after the second and third doses of the COVID-19 vaccine, and to determine the antibody titers in cases of spontaneous infection with SARS-CoV-2 after vaccination. From June 2021 to February 2023, IgG-type SARS-CoV-2 antibody titers were measured in 127 participants, including 74 outpatients and 53 members of staff, at the Osaka Dental University Hospital (64 males and 63 females, mean age 52.3 ± 19.0 years). Consistent with previous reports, the SARS-CoV-2 antibody titer decreased with time, not only after the second dose but also after the third dose of the vaccine if there was no spontaneous COVID-19 infection. We also confirmed that the third booster vaccination was effective in increasing the antibody titer. A total of 21 cases of natural infections were observed after administering two or more doses of the vaccine. Thirteen of these patients had post-infection antibody titers exceeding 40,000 AU/mL, and some cases continued to maintain antibody titers in the tens of thousands of AU/mL even after more than 6 months had passed since infection. The rise in and duration of antibody titers against SARS-CoV-2 are considered important indicators for confirming the efficacy of novel COVID-19 vaccines. A longitudinal follow-up of antibody titers after vaccination in larger studies is warranted.

Korean Red Ginseng Potentially Improves Maintaining Antibodies after COVID-19 Vaccination: A 24-Week Longitudinal Study.

Despite the effectiveness and safety of COVID-19 vaccines, vaccine-induced responses decline over time; thus, booster vaccines have been approved globally. In addition, interest in natural compounds capable of improving host immunity has increased. This study aimed to examine the effect of Korean Red Ginseng (KRG) on virus-specific antibodies after COVID-19 vaccination. We conducted a 24 week clinical pilot study of 350 healthy subjects who received two doses of the COVID-19 vaccine and a booster vaccination (third dose). These subjects were randomized 1:2 to the KRG and control groups. We evaluated antibody response five times: just before the second dose (baseline), 2 weeks, 4 weeks, 12 weeks after the second dose, and 4 weeks after the third dose. The primary endpoints were changes in COVID-19 spike antibody titers and neutralizing antibody titers. The antibody formation rate of the KRG group was sustained higher than that of the control group for 12 weeks after the second dose. This trend was prominently observed in those above 50 years old. We found that KRG can help to increase and maintain vaccine response, highlighting that KRG could potentially be used as an immunomodulator with COVID-19 vaccines.

Anti-human leukocyte antigen and anti-ABO antibodies after SARS-CoV-2 mRNA vaccination in kidney transplant recipients.

In this study, we evaluated whether SARS-CoV-2 mRNA vaccines induce anti-human leukocyte antigen (HLA) antibodies and anti- ABO blood type antibodies (ABOAb) in kidney transplant recipients (KTRs). Sixty-three adult KTRs with functioning grafts who received two doses of the SARS-CoV-2 mRNA vaccine were enrolled in this cohort. Changes in anti-ABO blood type immunoglobulin IgM and IgG antibody titers, flow panel reactive antibody (PRA), de novo donor-specific anti-human leukocyte antigen antibodies (DSA), and kidney allograft function before and after vaccination were evaluated. Only one patient experienced conversion from negative to positive flow PRA after vaccination. However, there was no DSA in single antigen flow-bead assays. The mean fluorescence intensity (MFI) in the eight DSA-positive recipients did not significantly change before and after vaccination (p=.383), and no additional DSA was produced after vaccination in those patients. No significant elevation of ABOAb titer was observed for either IgM (p=.438) or IgG (p=.526) after vaccination. There was no significant deterioration in estimated glomerular filtration rate (eGFR) after vaccination (p=.877) or elevation of the urine protein-to-creatinine ratio (p=.209) after vaccination. One episode of AMR was observed in addition to a preexisting acute cellular rejection. The SARS-CoV-2 mRNA vaccine did not induce anti-HLA antibody or ABOAb production in KTRs.

Association of a third vaccination with antibody levels and side reactions in essential workers: A prospective cohort study.

To evaluate the relationship between the change of titer and adverse events after the third vaccination for COVID-19 among healthcare workers. This was a prospective cohort study, and the follow-up period was from December 2021 to November 2023. A total of 392 healthcare workers aged over 20years who worked at the facility and wished to have vaccine antibody titers measured participated in this study. A third dose of BNT162b2 COVID-19 vaccine was administered to healthcare workers working at the hospital, and we evaluated the changes in antibody titers before and after the vaccine, as well as adverse reactions after vaccination. The primary endpoints were adverse reactions within 7days after the third dose of COVID-19 vaccine and the rate of increase in COVID-19 vaccine antibody titer at 4weeks. A total of 392 people participated in the study, of whom 358 participants had their antibody titers measured before and after the booster vaccination. The overall IgG geometric mean was 609 U/mL (561-663) before booster vaccination and increased to 18,735 U/mL (17,509-20,049) at 4weeks after vaccination (p<0.001). Multivariate analysis showed no statistically significant relationship between the primary endpoints, such as a change in antibody titer due to the presence of fever after vaccination or a change in antibody titer due to swelling at the vaccination site. Factors affecting the rate of increase in antibody titer, evaluated as secondary endpoints, were suggested to be age (1.02 (95% confidence interval (CI): 1.01-1.03)) and hypertension (0.66 (95% CI: 0.47-0.93)). In relation to the booster effect of the third dose of COVID-19 vaccination, there was no statistically significant difference in the presence of fever or use of antipyretic or other drugs.

Assessment of Antibody-Titer Changes after Second and Third Severe Acute Respiratory Syndrome Coronavirus 2 mRNA Vaccination in Japanese Post-Kidney-Transplant Patients.

Post-renal-transplant patients have a relatively low antibody-acquisition rate following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination. In this study, antibody titers were measured 5−6 months and 3 weeks to 3 months after the second and third SARS-CoV-2 mRNA vaccinations, respectively. Post-renal-transplant patients visiting our hospital who had received three SARS-CoV-2 mRNA vaccine doses were included in the study. SARS-CoV-2 immunoglobulin G antibody titers were measured three times: between 3 weeks and 3 months after the second vaccination, 5−6 months after the second vaccination, and between 3 weeks and 3 months after the third vaccination. A total of 62 (40 men and 22 women) were included, 44 of whom (71.0%) were antibody positive after their third vaccination. On comparing the antibody-acquired and antibody-non-acquired groups, body mass index (BMI, odds ratio [OR]: 1.44, 95% confidence interval [CI]: 1.07−1.93, p < 0.05) and the estimated glomerular filtration rate (eGFR, OR: 1.14, 95% CI: 1.06−1.24, p < 0.01) were associated with antibody acquisition. Therefore, in Japanese post-kidney-transplant patients, increases in the antibody-acquisition rate and absolute antibody titer after the third vaccination were observed, with BMI and eGFR associated with the antibody-acquisition rate.

Clinical analysis of hospital acquired mycoplasma pneumoniae infection after cardiac surgery: a case series.

Mycoplasma pneumoniae (MP) is a common pathogen of community-acquired respiratory infections. The clinical characteristics hospital-acquired MP infections are rarely reported in the literature. Our ward is mainly responsible for the management of patients during the perioperative period of cardiac surgery. Several patients had fever during the improvement of their condition after cardiac surgery, and the effect of upgrading antibiotics and increasing the antibacterial spectrum was not good. Using inpatient data of Guangdong Provincial People's Hospital, we conducted a retrospective case series study of hospital-acquired MP infection after cardiac surgery from January 2015 to December 2020 to investigate the clinical characteristics. Clinical data was extracted from patients with a confirmed diagnosis of MP infection after >48 hours of hospitalization. All analyses for this study were descriptive. Data were expressed as mean ± standard deviation (SD), median with range or number with percentage as appropriate. We totally included 22 patients. The time of onset of hospital-acquired MP infection after surgery was 23.32±12.57 days, and the duration of antibiotic use before the onset of infection was 4-40 days. Both fever and sore throat were the main symptoms of nosocomial MP infection, and the rash was the most common physical sign. Laboratory tests were normal for peripheral blood leukocyte count and procalcitonin in most patients (17 cases), while the lymphocyte count was decreased in 10 cases. A single serum anti-MP antibody titer ≥1:160 combined with clinical manifestations and imaging helped confirm nosocomial MP infection, although a double serum anti-MP antibody (four-fold change in titer) wasn't seen. With quinolone therapy, such as levofloxacin, all the patients' temperature gradually returned to normal and were discharged uneventfully. Patients after cardiac surgery should be aware of the presence of hospital-acquired MP infection when they develop new fever accompanied by atypical bacterial infection signs such as sore throat and rash during treatment. In such cases, changes in MP antibody titers need to be monitored and anti-MP therapy is required.

Changes in spike protein antibody titer over 90 days after the second dose of SARS-CoV-2 vaccine in Japanese dialysis patients

ObjectivesThere is no report on antibody titers after vaccination against SARS-CoV-2 in Japanese dialysis patients. As dialysis is different between Japan and other countries, changes in antibody titers were examined.MethodsBaseline characteristics and anti-spike protein antibody titers (Roche) over 90 days after administration of the BNT162b2 messenger RNA vaccine were investigated in dialysis patients.ResultsThe maximum anti-spike protein antibody titer after the second dose was 738 (327 to 1143) U/mL and was reached at 19 (17 to 24) days after the second dose. Antibody titers decreased over time, with titers of 770 (316 to 1089) U/mL at 15 days, 385 (203 to 690) U/mL at 30 days, 254 (138 to 423) U/mL at 60 days, and 208 (107 to 375) U/mL at 90 days after the second dose. When an antibody titer of 137 U/mL was assumed to be a measure related to breakthrough infection, the proportion of subjects with antibody titers exceeding this level was 90.1% at 15 days, 85.3% at 30 days, 75.0% at 60 days, and 65.4% at 90 days after the second dose. When a decrease in antibody titers below the assumed breakthrough level was defined as an event, subjects with a pre-dialysis albumin ≥ 3.5 g/dL were significantly less likely to experience an event than subjects with a pre-dialysis albumin < 3.5 g/dL.ConclusionsThe presence of anti-spike protein levels ≥ 313 U/mL at 30 days after the second vaccine dose might be a factor in maintaining enough antibody titers at 90 days after. Whether an additional vaccine dose is needed should be determined based on indicators serving as factors in maintaining antibody titers as well as the status of the spread of infection.

Clinico-Demographic Characteristics of Patients with SARS-CoV-2 Antibodies: A Single Tertiary Center Retrospective Study in Bohol, Philippines

Abstract Introduction/Objective Coronavirus Disease 2019 (COVID-19) caused by SARS-CoV-2 continues to be a global threat until the present. Most of the infected patients are asymptomatic which can be a challenge in controlling the spread of disease. Antibody detection by chemiluminescence immunoassay (CLIA) is a good complementary test to Real-Time Reverse Transcription – Polymerase Chain Reaction (rRT-PCR) as an indirect marker for disease. Methods/Case Report This retrospective study assessed the clinico-demographic characteristics of 184 SARS-CoV-2 IgM and IgG antibody-reactive patients at Gov. Celestino Gallares Memorial Hospital from July 1, 2020 – May 31, 2021. Results (if a Case Study enter NA) A total of 184 cases were included in the study out of 4,138 patients tested for anti-SARS-CoV-2 IgM and IgG antibodies by CLIA. Within this population, 97 were outpatients and 87 were inpatients. Majority of patients needing hospitalization were aged ≥60-year-old males (33.33%) and that the probability of being admitted decreases with younger age. Most of the outpatients who were reactive to antibodies against SARS-CoV-2 were frontline workers compared to non-frontline workers and non-workers (27.84% versus 1.03% and 19.59%). Most common comorbidities were hypertension (24.46%), cardiovascular disease (15.76%), diabetes mellitus (11.41%), and chronic kidney disease (11.41%). All five mortalities were diagnosed hypertensive who later developed critical disease. Conclusion The continued use of antibody detection by CLIA as a complementary test with rRT-PCR is still recommended not only for better detection of COVID-19 especially in asymptomatic patients but also to observe changes in antibody titer especially in the advent of COVID-19 vaccines.

Changes in anti-MDA5 antibody titres and serum cytokine levels before and after diagnosis of anti-MDA5 antibody-positive dermatomyositis.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive DM is characterized by rapidly progressive interstitial lung disease and has a poor prognosis. We aimed to investigate whether anti-MDA5 antibody titres and cytokine levels predict clinical course, and evaluate changes in both parameters before and after diagnosis. This was a retrospective, single-centre study in 38 patients with anti-MDA5 antibody-positive DM. We compared clinical characteristics and laboratory data at diagnosis between patients in the treatment response (n = 23) and non-response (n = 15) groups, and between those in the relapse (n = 5) and non-relapse (n = 24) groups. We also measured serum anti-MDA5 antibody titres and cytokine levels before and after diagnosis. The non-response group was older, had a higher ground-glass opacity score, lower PaO2/FiO2, higher CRP level, and higher anti-MDA5 antibody titre than the response group. No cytokines significantly differed between groups at diagnosis. The relapse group had a significantly higher anti-MDA5 antibody titre than the non-relapse group. In the survivor group, the anti-MDA5 antibody titre and levels of IFN-α, IFN-γ, monocyte chemotactic protein-1 (MCP-1), IL-6, IL-33, CRP, and ferritin were significantly lower 6 months post-treatment than at diagnosis. Macrophage-associated cytokines such as IL-6, IL-8, IL-18 and MCP-1 increased after anti-MDA5 antibody positivity in three patients who were anti-MDA5 antibody-positive before diagnosis. The anti-MDA5 antibody titre at diagnosis may predict the clinical course. Levels of macrophage-associated cytokines significantly declined at 6 months post-treatment, and they may have increased after anti-MDA5 antibody titre positivity.

A Bovine Viral Diarrhea Virus Type 1c Strain in China: Isolation, Identification, and Assessment of Pathogenicity in Rabbits.

Bovine viral diarrhea virus (BVDV) is an important animal pathogen and has a negative economic impact on cattle industries worldwide. In this study, the BVDV strain named BJ175170 was detected, isolated, and identified from cattle in Beijing, China, during herd screening by BVDV antigen-ELISA and indirect immunofluorescence assay (IFA). To investigate its genomic features, the characteristic 5'UTR region of the isolates were sequenced and BLAST analyzed. BVDV BJ175170 belongs to the BVDV-1c subtype, which differs from the Beijing prevalent BVDV strains. The BVDV particles were further observed by transmission electron microscopy (TEM). To evaluate the virulence of the BVDV BJ175170, the BVDV seronegative rabbits were intraperitoneally inoculated with the virus suspension. Blood samples were analyzed for changes in leukocyte number and antibody titer, and tissue samples were taken for histopathology analysis. These data confirmed again that rabbits could act as the reservoir of BVDV, which poses a small but non-zero risk of re-infection for BVDV-free cattle herds. To our knowledge, this is the first report of pathological changes in rabbits after exposure to BVDV-1c subtype, which could act as experimental reference. Meanwhile, the results of this study indicate that rabbits could act as a potential model for studying the mechanism of BVDV in vivo.

Examining the association between vaccine reactogenicity and antibody titer dynamics after the third dose of BNT162b2 vaccine using a mixed-effects model

BackgroundTo mitigate the COVID-19 pandemic, many countries have recommended the use of booster vaccinations. The relationship between the degree of adverse vaccine reactions and elevated antibody titers is of interest; however, no studies have investigated the temporal changes in antibody titers based on repeated measurements after a third dose of the BNT162b2 vaccine. MethodsThis prospective longitudinal cohort study was conducted with 62 healthcare workers who received a third dose of the BNT162b2 at Okayama University Hospital, Japan. Venous blood draw and fingertip whole blood test sample collection were conducted at the early (3–13 days) and 1-month time points; only FWT sample collection was conducted at the 2-month time point. Information on adverse reactions within 1 week after vaccination was also obtained. The association between fever of 37.5 °C or higher and antibody titers after the third dose of BNT162b2 was examined using a mixed-effects model and Poisson regression with robust variance. ResultsA trend toward higher antibody titers in the early period after vaccination was observed in the febrile individuals, but the differences were not significant at 1 and 2 months post-vaccination (the partial regression coefficient for fever was 8094.3 [-1910.2, 18,098.8] at 1 month after vaccination, and 1764.1 [-4133.9, 7662.1] at 2 months after vaccination in the adjusted models). ConclusionThe findings suggest that the presence of fever after the third vaccine does not predict a sustained elevation in serum antibody titers.

Age- and sex-based changes in spike protein antibody status after SARS-CoV-2 vaccination and effect of past-infection in healthcare workers in Osaka

ObjectiveWe aimed to compare the changes in SARS-CoV-2 spike protein antibody titres based on age group and sex using paired blood sampling after vaccination in association with the presence of nucleocapsid protein antibody.MethodsAll participants were healthcare workers at Yao Municipal Hospital in Osaka who voluntarily provided peripheral blood samples (n = 636, men/women 151/485, mean age 45 years). We investigated the serial changes in SARS-CoV-2 spike protein antibody titres at 1 and 7 months after the second vaccination regarding their relationship with sex and age group. At 7 months, we also examined anti-nucleocapsid assays. Antibody titres were shown as logarithmic values and the differences were assessed using a paired or unpaired student’s t-test as appropriate.ResultsAmong participants younger than 30 years, the antibody titres of spike protein were significantly higher in women one (p = 0.005) and seven (p = 0.038) months after vaccination. However, among those aged 30–49 years, the antibody titres were not different between the sexes at either follow-up time point. In contrast, among those aged 50–59 years, between-sex differences in antibody titres were observed only at 7 months, which was associated with a significant reduction in men. A significant negative correlation was observed between the antibody titres for spike protein at both time points in participants with positive nucleocapsid protein antibody at 7 months (r = − 0.467, p = 0.043), although a significant positive correlation was observed in those with negative results (r = 0.645, p < 0.001),ConclusionsBetween-sex differences in SARS-CoV-2 spike protein antibody titres by paired blood sampling at different time points after vaccination depended on age group. The presence of nucleocapsid protein antibody was associated with changes in spike protein antibody titres after vaccination.