45,944 research outputs found
Behaviour of non-donor specific antibodies during rapid re-synthesis of donor specific HLA antibodies after antibody incompatible renal transplantation
Background:
HLA directed antibodies play an important role in acute and chronic allograft rejection. During viral infection of a patient with HLA antibodies, the HLA antibody levels may rise even though there is no new immunization with antigen. However it is not known whether the converse occurs, and whether changes on non-donor specific antibodies are associated with any outcomes following HLA antibody incompatible renal transplantation.
Methods:
55 patients, 31 women and 24 men, who underwent HLAi renal transplant in our center from September 2005 to September 2010 were included in the studies. We analysed the data using two different approaches, based on; i) DSA levels and ii) rejection episode post transplant. HLA antibody levels were measured during the early post transplant period and corresponding CMV, VZV and Anti-HBs IgG antibody levels and blood group IgG, IgM and IgA antibodies were quantified.
Results:
Despite a significant DSA antibody rise no significant non-donor specific HLA antibody, viral or blood group antibody rise was found. In rejection episode analyses, multiple logistic regression modelling showed that change in the DSA was significantly associated with rejection (p = 0.002), even when adjusted for other antibody levels. No other antibody levels were predictive of rejection. Increase in DSA from pre treatment to a post transplant peak of 1000 was equivalent to an increased chance of rejection with an odds ratio of 1.47 (1.08, 2.00).
Conclusion:
In spite of increases or decreases in the DSA levels, there were no changes in the viral or the blood group antibodies in these patients. Thus the DSA rise is specific in contrast to the viral, blood group or third party antibodies post transplantation. Increases in the DSA post transplant in comparison to pre-treatment are strongly associated with occurrence of rejection
Anti-influenza antibody level after vaccination in north of Iran
Objective:Influenza is a highly transmitted disease and about 10% of the world's population is affected by this disease annually. The aim of this research was to study the variation of serum antibody levels among subjects who had already been vaccinated against influenza. Methods And Materials:This descriptive-analytical study was carried out on 196 subjects who had influenza vaccination (influvac 2005/2006) and on 200 subjects who were matched with the vaccinated subjects by their ages in Gorgan which is located in the northeast of Iran. The subject's sera were prepared seven weeks after the influenza vaccination. Their serum antibody levels were determinated by the heamaglutination inhibition test. Results:The antibody titre in 81 subjects of the vaccinated group and in 175 subjects of the control group was less then 1/40. The mean antibody titre of the vaccinated subjects and the control group was 143.4±10.89 and 18.34±3.2, respectively. The difference was statistically significant (P value=0.000). Conclusion:The findings showed that the mean titre of the antibodies in the vaccinated and control groups was statistically different. This means that the influenza vaccine has good efficacy in our population
Lifestyle, dietary factors and antibody levels to oral bacteria in cancer-free participants of a European cohort study
Background—Increasing evidence suggests that oral microbiota play a pivotal role in chronic diseases, in addition to the well-established role in periodontal disease. Moreover, recent studies suggest that oral bacteria may also be involved in carcinogenesis; periodontal disease has been linked several cancers. In this study, we examined whether lifestyle factors have an impact on antibody levels to oral bacteria.
Methods—Data on demographic characteristics, lifestyle factors, and medical conditions were obtained at the time of blood sample collection. For the current analysis, we measured antibody levels to 25 oral bacteria in 395 cancer-free individuals using an immunoblot array. Combined total immunglobin G (IgG) levels were obtained by summing concentrations for all oral bacteria measured.
Results—IgG antibody levels were substantially lower among current and former smokers (1697 and 1677 ng/mL, respectively) than never smokers (1960 ng/mL; p-trend = 0.01), but did not vary by other factors, including BMI, diabetes, physical activity, or by dietary factors, after adjusting for age, sex, education, country and smoking status. The highest levels of total IgG were found among individuals with low education (2419 ng/mL).
Conclusions—Our findings on smoking are consistent with previous studies and support the notion that smokers have a compromised humoral immune response. Moreover, other major factors known to be associated with inflammatory markers, including obesity, were not associated with antibody levels to a large number of oral bacteria
Post-treatment follow-up study of abdominal cystic echinococcosis in Tibetan communities of northwest Sichuan Province, China
Background: Human cystic echinococcosis (CE), caused by the larval stage of Echinococcus granulosus, with the liver as the
most frequently affected organ, is known to be highly endemic in Tibetan communities of northwest Sichuan Province.
Antiparasitic treatment with albendazole remains the primary choice for the great majority of patients in this resource-poor
remote area, though surgery is the most common approach for CE therapy that has the potential to remove cysts and lead
to complete cure. The current prospective study aimed to assess the effectiveness of community based use of cyclic
albendazole treatment in Tibetan CE cases, and concurrently monitor the changes of serum specific antibody levels during
treatment.
Methodology/Principal Findings: Ultrasonography was applied for diagnosis and follow-up of CE cases after cyclic
albendazole treatment in Tibetan communities of Sichuan Province during 2006 to 2008, and serum specific IgG antibody
levels against Echinococcus granulosus recombinant antigen B in ELISA was concurrently monitored in these cases. A total of
196 CE cases were identified by ultrasound, of which 37 (18.9%) showed evidence of spontaneous healing/involution of
hepatic cyst(s) with CE4 or CE5 presentations. Of 49 enrolled CE cases for treatment follow-up, 32.7% (16) were considered
to be cured based on B-ultrasound after 6 months to 30 months regular albendazole treatment, 49.0% (24) were improved,
14.3% (7) remained unchanged, and 4.1% (2) became aggravated. In general, patients with CE2 type cysts (daughter cysts
present) needed a longer treatment course for cure (26.4 months), compared to cases with CE1 (univesicular cysts) (20.4
months) or CE3 type (detached cyst membrane or partial degeneration of daughter cysts) (9 months). In addition, the
curative duration was longer in patients with large (.10 cm) cysts (22.3 months), compared to cases with medium (5–
10 cm) cysts (17.3 months) or patients with small (,5 cm) cysts (6 months). At diagnosis, seven (53.8%) of 13 cases with CE1
type cysts without any previous intervention showed negative specific IgG antibody response to E. granulosus recombinant
antigen B (rAgB). However, following 3 months to 18 months albendazole therapy, six of these 7 initially seronegative CE1
cases sero-converted to be specific IgG antibody positive, and concurrently ultrasound scan showed that cysts changed to
CE3a from CE1 type in all the six CE cases. Two major profiles of serum specific IgG antibody dynamics during albendazole
treatment were apparent in CE cases: (i) presenting as initial elevation followed by subsequent decline, or (ii) a persistent
decline. Despite a decline, however, specific antibody levels remained positive in most improved or cured CE cases.
Conclusions: This was the first attempt to follow up community-screened cystic echinococcosis patients after albendazole
therapy using ultrasonography and serology in an endemic Tibetan region. Cyclic albendazole treatment proved to be
effective in the great majority of CE cases in this resource-poor area, but periodic abdominal ultrasound examination was
necessary to guide appropriate treatment. Oral albendazole for over 18 months was more likely to result in CE cure. Poor
drug compliance resulted in less good outcomes. Serology with recombinant antigen B could provide additional limited
information about the effectiveness of albendazole in CE cases. Post-treatment positive specific IgG antibody
seroconversion, in initially seronegative, CE1 patients was considered a good indication for positive therapeutic efficacy
of albendazole
Independent and joint effects of antibodies to human heat-shock protein 60 and Chlamydia pneumoniae infection in the development of coronary atherosclerosis
Background—Studies have suggested that the prevalence of antibodies against heat-shock proteins (HSPs), Chlamydia
pneumoniae (Cpn), and cytomegalovirus (CMV) is associated with coronary artery disease (CAD), but the independent
or joint effects of human (h) HSP60 antibodies and these pathogens in patients have not been fully elucidated.
Methods and Results—A total of 405 subjects (276 patients with CAD and 129 control individuals) were tested for serum
antibodies to hHSP60, Cpn, and CMV immediate-early-1 (IE1) antigens. Patients were also assessed for serum cholesterol, triglyceride levels, and smoking habit. Significantly elevated levels of antibodies to hHSP60 and Cpn but
not to CMV-IE1 antigens were documented in CAD patients. Multiple logistic regression analysis and subanalyses of
selected subjects showed that these associations were independent of age, sex, smoking, and serum lipid levels.
Antibodies to hHSP60 and Cpn did not correlate quantitatively; however, the relative risk of disease development was substantially increased in subjects with high antibody levels to both hHSP60 and Cpn, reaching an odds ratio of 82.0 (95% CI 10.6 to 625.0).
Conclusions—High levels of antibodies to hHSP60 and Cpn are independent risk factors for coronary atherosclerosis, but
their simultaneous presence substantially increases the risk for disease development
Variable protection against experimental broiler necrotic enteritis after immunisation with the C-terminal fragment of Clostridium perfringens alpha-toxin and a non-toxic NetB variant
Necrotic enteritis toxin B (NetB) is a pore-forming toxin produced by Clostridium perfringens and has been shown to play a key role in avian necrotic enteritis (NE), a disease causing significant costs to the poultry production industry worldwide. The aim of this work was to determine whether immunisation with a non-toxic variant of NetB (NetB W262A) and the C-terminal fragment of C. perfringens alpha-toxin (CPA247–370) would provide protection against experimental NE. Immunised animals with either antigen or a combination of antigens developed serum antibody levels against NetB and CPA. When CPA247–370 and NetB W262A were used in combination as immunogens, an increased protection was observed after oral challenge by individual dosing, but not after in-feed challenge
γδ T cells affect IL-4 production and B-cell tolerance
γδ T cells can influence specific antibody responses. Here, we report that mice deficient in individual γδ T-cell subsets have altered levels of serum antibodies, including all major subclasses, sometimes regardless of the presence of αβ T cells. One strain with a partial γδ deficiency that increases IgE antibodies also displayed increases in IL-4–producing T cells (both residual γδ T cells and αβ T cells) and in systemic IL-4 levels. Its B cells expressed IL-4–regulated inhibitory receptors (CD5, CD22, and CD32) at diminished levels, whereas IL-4–inducible IL-4 receptor α and MHCII were increased. They also showed signs of activation and spontaneously formed germinal centers. These mice displayed IgE-dependent features found in hyper-IgE syndrome and developed antichromatin, antinuclear, and anticytoplasmic autoantibodies. In contrast, mice deficient in all γδ T cells had nearly unchanged Ig levels and did not develop autoantibodies. Removing IL-4 abrogated the increases in IgE, antichromatin antibodies, and autoantibodies in the partially γδ-deficient mice. Our data suggest that γδ T cells, controlled by their own cross-talk, affect IL-4 production, B-cell activation, and B-cell tolerance
Evaluation of milk yield losses associated with Salmonella antibodies in bulk-tank milk in bovine dairy herds
The effect of Salmonella on milk production is not well established in cattle. The objective of this study was to investigate whether introduction of Salmonella into dairy cattle herds was associated with reduced milk yield and the duration of any effect. Longitudinal data from 2005 through 2009 were used, with data from 12 months before until 18 months after the estimated date of infection. Twenty-eight case herds were selected based on an increase in the level of Salmonella specific antibodies in bulk-tank milk from < 10 corrected optic density percentage (ODC%) to ≥ 70 ODC% between two consecutive 3-monthly measurements in the Danish Salmonella surveillance program. All selected case herds were conventional Danish Holstein herds. Control herds (n = 40) were selected randomly from Danish Holstein herds with Salmonella antibody levels consistently < 10
ODC%. A date of herd infection was randomly allocated to the control herds. Hierarchical mixed effect models with the outcome test day energy corrected milk yield (ECM)/cow were used to investigate the daily milk yield before and after the estimated herd infection date for cows in parity 1, 2 and 3+. Control herds were used to evaluate whether the effects in the case herds could be reproduced in herds without Salmonella infection. Herd size, days in milk, somatic cell count, season, and year were included in the models. The key results were that first parity cow yield was reduced by a mean of 1.4 kg (95% CI: 0.5 to 2.3) ECM/cow per day from seven to 15 months after the estimated herd infection date, compared with first parity cows in the same herds in the 12 months before the estimated herd infection date. Yield for parity 3+ was reduced by a mean of 3.0 kg (95% CI: 1.3 to 4.8) ECM/cow per day from seven to 15 months after herd infection compared with parity 3+ cows in the 12 months before the estimated herd infection. There were minor differences in yield in second parity cows before and after herd infection, and no difference between cows in control herds before and after the simulated infection date. There was a significant drop in milk yield in affected herds and the reduction was detectable several months after the increase in bulk-tank milk Salmonella antibodies. It took more than a year for milk yield to return to pre- infection levels
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