Serological Markers of Recent Campylobacter jejuni Infection in Patients with Guillain-Barré Syndrome in the State of Piauí, Brazil, 2014-2016

Expression of recombinant Omp18 and MOMP of Campylobacter jejuni and the determination of their suitability as antigens for serological diagnosis of campylobacteriosis in animals

Background and Aim

Campylobacteriosis causes gastrointestinal tract lesions in adults and children and may result in severe complications. The primary sources of infection are infected animals and animal products. Immunochemical methods effectively diagnose intestinal infections but require highly specific antigens to detect their antibodies. This study aimed to obtain two recombinant immunogenic antigens of Campylobacter jejuni, an outer membrane protein with a molecular weight of 18 kDa (Omp18) and the major outer membrane protein (MOMP) with a molecular weight of 45 kDa, and evaluate their suitability for the serological diagnosis of campylobacteriosis using immunochromatographic assay (ICA).

Materials and Methods

The C. jejuni Omp18 and MOMP gene sequences were synthesized de novo (Macrogen, Korea) and cloned into the pET32 expression plasmid. Using these genetic constructs, electrocompetent cells of the Escherichia coli BL21 strain were transformed and cultured under various conditions. Antigens were purified and refolded using metal affinity chromatography. The properties of the purified proteins were studied by western blotting, liquid chromatography with tandem mass spectrometry, and enzyme-linked immunosorbent assay (ELISA).

Results

We developed two recombinant E. coli BL21 cells producing rOmp18 and Recombinant MOMP (rMOMP) antigens with molecular weights of 36 and 64 kDa, respectively. Amino acid sequence analysis of the obtained antigens showed complete homology with the reference sequences in the PubMed NCBI database. Western blotting using positive-control sera demonstrated the specificity of the recombinant antigens. The results of ELISA with 94 bovine sera showed the interaction of recombinant antigens with specific antibodies.

Conclusion

The obtained rOmp18 and rMOMP antigens can detect antibodies in the serum of infected or recovered animals and can be used to develop ICA.

Antecedent infections in Guillain-Barré syndrome in endemic areas of arbovirus transmission: A multinational case-control study

Half of the world's population is at risk of arthropod‐borne virus (arbovirus) infections. Several arbovirus infections have been associated with Guillain‐Barré syndrome (GBS). We investigated whether arboviruses are driving GBS beyond epidemic phases of transmission and studied the antibody response to glycolipids. The protocol of the International Guillain‐Barré syndrome Outcome Study (IGOS), an observational prospective cohort study, was adapted to a case‐control design. Serum samples were tested for a recent infection with Zika virus (ZIKV), dengue virus (DENV), chikungunya (CHIKV) virus, hepatitis E virus, Epstein‐Barr virus (EBV), cytomegalovirus (CMV), Campylobacter jejuni, and Mycoplasma pneumoniae, and for antibodies to glycolipids. Forty‐nine patients were included from Brazil (63%), Argentina (14%), and Malaysia (22%). Evidence of a recent infection was found in 27/49 (55%) patients: C jejuni (n = 15, 31%), M pneumoniae (n = 5, 10%), CHIKV (n = 2, 4%), EBV (n = 1, 2%), C jejuni and M pneumoniae (n = 2, 4%), CMV and DENV (n = 1, 2%), and C jejuni and DENV (n = 1, 2%). In 22 patients, 35 paired controls were collected. Odds ratio for recent infections did not significantly differ between cases and controls. No typical anti‐ganglioside antibody binding was associated with recent arbovirus infection. We conclude that arbovirus infections occur in GBS patients outside of epidemic viral transmission, although not significantly more than in controls. Broad infection and anti‐ganglioside antibody serology are important to establish the most likely pathogenic trigger in GBS patients. Larger studies are necessary to determine the association between arboviruses and GBS.

Genotypical Relationship Between Human and Poultry Strains of Campylobacter jejuni

This study aimed to compare the genotype diversity of C. jejuni isolates. From the total of 64 C. jejuni strains evaluated, 44 were isolated from broiler carcasses (2015-2016) and 20 from hospitalized patients with gastroenteritis caused by the microorganism (2000-2006). The strains were correlated for the presence of flaA, pldA, cadF, ciaB, cdtABC, luxS, dnaJ, cbrA, htrA, pVir, Hcp, cstII, and neuA genes by PCR (polymerase chain reaction) and for phylogenetic proximity by PFGE (pulsed-field gel electrophoresis). Of the total strains studied, 28 (43.7%) presented all the studied genes, except pVir. Among these strains, 25 (89.3%) were of poultry origin. Poultry strains showed a higher prevalence (P < 0.05) of genes linked to adhesion, colonization, invasion, cytotoxicity, biofilm formation, and adaptation to adverse conditions. Additionally, the profile that denotes the presence of all genes identified in the study (P1) was identified in 56.8% of poultry strains and in 15.0% of human strains. Molecular typing analysis identified five pulsotypes, none of which grouped strains from different origins. Although human strains were from hospitalized patients, they presented limited virulence capacity and adaptability to adverse conditions compared to chicken carcasses, besides being different in molecular typing. However, the ability to cause Guillain-Barré Syndrome is equal for both strains. In general, poultry strains, being more recent, are more specialized to adapt to the environment, invade, and cause disease in the human host.

Incidence of Guillain-Barré Syndrome (GBS) in Latin America and the Caribbean before and during the 2015-2016 Zika virus epidemic: A systematic review and meta-analysis

BACKGROUND

A severe neurological disorder, Guillain-Barré syndrome (GBS) is the leading cause of acute flaccid paralysis. Enhanced surveillance of GBS in Latin America and the Caribbean (LAC) following the 2015-2016 Zika virus (ZIKV) epidemic presents an opportunity to estimate, for the first time, the regional incidence of GBS.

METHODS AND FINDINGS

For this systematic review and meta-analysis, we searched nine scientific databases and grey literature from January 1, 1980 to October 1, 2018. Sources with primary data on incident GBS cases in LAC within a well-defined population and timeframe, published in English, Spanish, Portuguese, or French, were included. We calculated the annual GBS incidence rates (IRs) and 95% confidence intervals (CIs) for each source based on published data. Following an assessment of heterogeneity, we used random-effects meta-analysis to calculate the pooled annual IR of GBS. The study is registered with PROSPERO, number CRD42018086659. Of the 6568 initial citation hits, 31 were eligible for inclusion. Background annual GBS IRs in Latin America ranged from 0.40 in Brazil to 2.12/100,000 in Chile. The pooled annual IR in the Caribbean was 1.64 (95% CI 1.29-2.12, I2<0.01, p = 0.44). During the ZIKV epidemic, GBS IRs ranged from 0.62 in Mexico to 9.35/100,000 in Martinique. GBS increased 2.6 (95% CI 2.3-2.9) times during ZIKV and 1.9 (95% CI 1.1-3.4) times during chikungunya outbreaks over background rates. A limitation of this review is that the studies included employed different methodologies to find and ascertain cases of GBS, which could contribute to IR heterogeneity. In addition, it is important to consider that data on GBS are lacking for many countries in the region.

CONCLUSIONS

Background IRs of GBS appear to peak during arboviral disease outbreaks. The current review contributes to an understanding of the epidemiology of GBS in the LAC region, which can inform healthcare system planning and preparedness, particularly during arboviral epidemics.

TRIAL REGISTRATION

Registered with PROSPERO: CRD42018086659.