METHODS: We applied H. pylori multiplex serology to measure antibody responses to 13 H. pylori proteins in prediagnostic serum samples from 485 colorectal cancer cases and 485 matched controls nested within the EPIC study. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using multivariable conditional logistic regression to estimate the association of H. pylori overall and protein-specific seropositivity with odds of developing colorectal cancer.
RESULTS: Fifty-one percent of colorectal cancer cases were H. pylori seropositive compared with 44% of controls, resulting in an OR of 1.36 (95% CI, 1.00-1.85). Among the 13 individual H. pylori proteins, the association was driven mostly by seropositivity to Helicobacter cysteine-rich protein C (HcpC; OR: 1.66; 95% CI, 1.19-2.30) and Vacuolating cytotoxin A (VacA) (OR: 1.34; 95% CI, 0.99-1.82), the latter being nonstatistically significant only in the fully adjusted model.
CONCLUSIONS: In this prospective multicenter European study, antibody responses to H. pylori proteins, specifically HcpC and VacA, were associated with an increased risk of developing colorectal cancer.
IMPACT: Biological mechanisms for a potential causal role of H. pylori in colorectal carcinogenesis need to be elucidated, and subsequently whether H. pylori eradication may decrease colorectal cancer incidence.
METHODS: In this study we have designed new live-attenuated vaccine vectors based on recombinant vesicular stomatitis viruses (rVSV) expressing NiV glycoproteins (G or F) or nucleoprotein (N) and evaluated their protective efficacy in Syrian hamsters, an established NiV animal disease model. We further characterized the humoral immune response to vaccination in hamsters using ELISA and neutralization assays and performed serum transfer studies.
RESULTS: Vaccination of Syrian hamsters with a single dose of the rVSV vaccine vectors resulted in strong humoral immune responses with neutralizing activities found only in those animals vaccinated with rVSV expressing NiV G or F proteins. Vaccinated animals with neutralizing antibody responses were completely protected from lethal NiV disease, whereas animals vaccinated with rVSV expressing NiV N showed only partial protection. Protection of NiV G or F vaccinated animals was conferred by antibodies, most likely the neutralizing fraction, as demonstrated by serum transfer studies. Protection of N-vaccinated hamsters was not antibody-dependent indicating a role of adaptive cellular responses for protection.
CONCLUSIONS: The rVSV vectors expressing Nipah virus G or F are prime candidates for new 'emergency vaccines' to be utilized for NiV outbreak management.
MATERIALS AND METHODS: Twenty original studies were identified after systematically searching five databases. The majority (n = 11) compared serum anti-Porphyromonas gingivalis (Pg) and/or anti-Aggregatibacter actinomycetemcomitans (Aa) IgG antibody responses between CHD patients and control participants. The strength of the association between serum anti-Pg antibodies and CHD (n = 10) and serum anti-Aa antibodies and CHD (n = 6) was investigated using a meta-analysis approach separately.
RESULTS: Most studies (61%) reported that the serum IgG antibody responses were elevated in CHD patients than in controls. The meta-analyses showed a significant association between elevated serum IgG antibody responses (anti-Pg and anti-Aa) and CHD, with pooled odds ratios of 1.23 [95% confidence interval (CI): 1.09-1.38, p = .001] and 1.25 (95% CI: 1.04-1.47, p = .0004), respectively.
CONCLUSIONS: A modest increase of CHD events in individuals with higher serum anti-Pg and anti-Aa IgG antibody responses may support their use as potential biomarkers to detect and monitor at-risk populations. However, the observed inconsistencies with the design and interpretation of immunoassays warrant standardization of the immunoassays assessing antibody responses against periodontal bacteria.
METHODS AND RESULTS: Bioinformatics analysis showed that there were three potential linear B-cell epitopes and four conformational B-cell epitopes predicted from annexin B30, respectively. Full-length annexin B30 was cloned and expressed in Escherichia coli BL21(DE3). In the presence of adjuvants, the soluble recombinant protein was evaluated for its protective efficacy in two independent vaccine trials. Immunization of CBA mice with recombinant annexin B30 formulated either in alum only or alum/CpG induced a mixed Th1/Th2 cytokine profile but no significant protection against schistosome infection was detected.
CONCLUSION: Recombinant annexin B30 did not confer significant protection against the parasite. The molecule may not be suitable for vaccine development. However, it could be an ideal biomarker recommended for immunodiagnostics development.