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European Journal of Microbiology and Immunology
Authors: Cosme Alvarado-Esquivel, Luis Francisco Sánchez-Anguiano, Jesús Hernández-Tinoco, Emilio Arreola-Cháidez, Juan López, Karla Itzel Salcido-Meraz, Sergio Estrada-Martínez, José Antonio Navarrete-Flores, Alma Rosa Pérez-Álamos, Marcia Hernández-Ochoa, Elizabeth Rábago-Sánchez, and Oliver Liesenfeld

Through an age- and sex-matched case-control study, we sought to determine whether female sex workers have an increased risk of Toxoplasma gondii exposure and to determine the sociodemographic, work, clinical, and behavioral characteristics of these workers associated with T. gondii exposure. Female workers (n = 136) and controls (n = 272) were examined with enzyme-linked immunoassays (EIA) for the presence of anti-Toxoplasma IgG and IgM antibodies. IgM positive sera were additionally tested with enzyme linked-fluorescence immunoassay (ELFA). Anti-T. gondii IgG antibodies were found in 21 (15.44%) of 136 cases and in 10 (3.67%) of 272 controls (OR = 4.05; 95% CI: 1.84–8.89; P = 0.0001). Anti-T. gondii IgG levels higher than 150 IU/ml were found in 13 (9.6%) of 136 cases and in 8 (2.9%) of 272 controls (P = 0.007). Anti-T. gondii IgM antibodies were found in two cases and in six controls by EIA, but all were negative by ELFA. T. gondii seropositivity was associated with being born out of Durango State (OR = 10.47; 95% CI: 2.9–36.8; P < 0.01), injuries during sex work (OR = 6.30; 95% CI: 1.1–33.7; P = 0.03), and soil contact (OR = 4.11; 95% CI: 1.2–14.0; P = 0.02). This is the first report of an association of T. gondii infection and female sex workers.

Open access

Rapid and accurate diagnosis of influenza is important for patient management and infection control. We determined the performance of the cobas® Influenza A/B assay, a rapid automated nucleic acid assay performed on the cobas® Liat System for qualitative detection of influenza A and influenza B from nasopharyngeal (NP) swab specimens. Retrospective frozen and prospectively collected NP swabs from patients with signs and symptoms of influenza collected in universal transport medium (UTM) were tested at multiple sites including CLIA-waived sites using the cobas® Influenza A/B assay. Results were compared to the Prodesse ProFlu+ assay and to viral culture. Compared to the Prodesse ProFlu+ Assay, sensitivities of the cobas® Influenza A/B assay for influenza A and B were 97.7 and 98.6%, respectively; specificity was 99.2 and 99.4%. Compared to viral culture, the cobas® Influenza A/B assay showed sensitivities of 97.5 and 96.9% for influenza virus A and B, respectively; specificities were 97.9% for both viruses. Polymerase chain reaction (PCR)/sequencing showed that the majority of viral culture negative but cobas® Influenza A/B positive results were true positive results, indicating that the cobas® Influenza A/B assay has higher sensitivity compared to viral culture.

In conclusion, the excellent accuracy, rapid time to result, and remarkable ease of use make the cobas® Influenza A/B nucleic acid assay for use on the cobas® Liat System a highly suitable point-of-care solution for the management of patients with suspected influenza A and B infection.

Open access
European Journal of Microbiology and Immunology
Authors: U. Erben, N. N. Pawlowski, M. M. Heimesaat, C. Loddenkemper, K. Doerfel, S. Spieckermann, B. Siegmund, and A. A. Kühl

Targeting human CD2 with the monoclonal antibody (mAb) CB.219 reduces intestinal inflammation in a colitis model where T cells carry human CD2. Here, we asked whether this mAb has adverse effects on infection control.

Mice expressing human CD2 on T cells (huCD2tg) were orally infected with Toxoplasma (T.) gondii and treated with the human CD2-specific mAb CB.219 in a preventive setting. The intestinal T. gondii loads in CB.219 treated mice did not differ from the control group. Histologically, huCD2tg mice showed moderate ileal inflammation that did not change with CB.219 treatment. In the ileum, CB.219 treatment reduced the protein levels of interferon-γ, transforming growth factor β and interleukin-6, whereas interleukin- 18 mRNA was slightly increased. The infiltration of neutrophils, macrophages, and T cells into the ileum was unaffected by CB.219 treatment. However, CB.219 treatment decreased the numbers of forkhead box P3+ regulatory T cells (Treg) in ileum and liver of huCD2tg mice. This was confirmed in vitro using human peripheral blood mononuclear cells.

Taken together, targeting CD2+ T cells by the human CD2 mAb CB.219 does not prevent beneficial immune reactions necessary for pathogen control. Further experiments will address gut specificity, underlying mechanisms, and general applicability of CB.219 treatment.

Open access
European Journal of Microbiology and Immunology
Authors: Marie E. Alutis, Ursula Grundmann, André Fischer, Ulrike Hagen, Anja A. Kühl, Ulf B. Göbel, Stefan Bereswill, and Markus M. Heimesaat

Matrix metalloproteinases (MMP)-2 and -9 (also referred to gelatinases-A and -B, respectively) are upregulated in the inflamed gut of mice and men. We recently demonstrated that synthetic gelatinase blockage reduced large intestinal pro-inflammatory immune responses and apoptosis following murine Campylobacter (C.) jejuni infection. In order to address which gelatinase mediates C. jejuni-induced immune responses, gnotobiotic MMP-2−/−, MMP-9−/−, and wildtype (WT) mice were generated by broadspectrum antibiotic treatment and perorally infected with C. jejuni strain 81-176. The pathogen stably colonized the murine intestinal tract irrespective of the genotype but did not translocate to extra-intestinal compartments. At days 8 and 14 postinfection (p.i.), less pronounced colonic histopathological changes were observed in infected MMP-2−/− mice, less distinct epithelial apoptosis, but more epithelial proliferation in both MMP-2−/− and MMP-9−/− mice, as compared to WT controls. Reduced immune responses in gelatinase- deficient mice were characterized by lower numbers of effector as well as innate and adaptive immune cells within the colonic mucosa and lamina propria. The expression of IL-22, IL-18, IL-17A, and IL-1β mRNA was higher in the colon of MMP-2−/− as compared to WT mice. In conclusion, both MMP-2 and MMP-9 are differentially involved in mediating C. jejuni-induced intestinal immunopathology.

Open access
European Journal of Microbiology and Immunology
Authors: Markus M. Heimesaat, Gül Karadas, André Fischer, Ulf B. Göbel, Thomas Alter, Stefan Bereswill, and Greta Gölz

Sporadic cases of gastroenteritis have been attributed to Arcobacter butzleri infection, but information about the underlying immunopathological mechanisms is scarce. We have recently shown that experimental A. butzleri infection induces intestinal, extraintestinal and systemic immune responses in gnotobiotic IL-10−/− mice. The aim of the present study was to investigate the immunopathological role of Toll-like Receptor-4, the receptor for lipopolysaccharide and lipooligosaccharide of Gram-negative bacteria, during murine A. butzleri infection. To address this, gnotobiotic IL-10−/− mice lacking TLR-4 were generated by broadspectrum antibiotic treatment and perorally infected with two different A. butzleri strains isolated from a patient (CCUG 30485) or fresh chicken meat (C1), respectively. Bacteria of either strain stably colonized the ilea of mice irrespective of their genotype at days 6 and 16 postinfection. As compared to IL-10−/− control animals, TLR-4−/− IL-10−/− mice were protected from A. butzleri-induced ileal apoptosis, from ileal influx of adaptive immune cells including T lymphocytes, regulatory T-cells and B lymphocytes, and from increased ileal IFN secretion. Given that TLR-4-signaling is essential for A. butzleri-induced intestinal inflammation, we conclude that bacterial lipooligosaccharide or lipopolysaccharide compounds aggravate intestinal inflammation and may thus represent major virulence factors of Arcobacter. Future studies need to further unravel the molecular mechanisms of TLR-4-mediated A. butzleri-host interactions.

Open access

Arcobacter butzleri causes sporadic cases of gastroenteritis, but the underlying immunopathological mechanisms of infection are unknown. We have recently demonstrated that A. butzleri-infected gnotobiotic IL-10−/− mice were clinically unaffected but exhibited intestinal and systemic inflammatory immune responses. For the first time, we here investigated the role of Toll-like receptor (TLR)-4, the main receptor for lipopolysaccharide and lipooligosaccharide of Gram-negative bacteria, in murine arcobacteriosis. Gnotobiotic TLR-4/IL-10-double deficient (TLR-4−/− IL-10−/−) and IL-10−/− control mice generated by broad-spectrum antibiotics were perorally infected with A. butzleri. Until day 16 postinfection, mice of either genotype were stably colonized with the pathogen, but fecal bacterial loads were approximately 0.5–2.0 log lower in TLR-4−/− IL-10−/− as compared to IL-10−/− mice. A. butzleri-infected TLR-4−/− IL-10−/− mice displayed less pronounced colonic apoptosis accompanied by lower numbers of macrophages and monocytes, T lymphocytes, regulatory T-cells, and B lymphocytes within the colonic mucosa and lamina propria as compared to IL-10−/− mice. Furthermore, colonic concentrations of nitric oxide, TNF, IL-6, MCP-1, and, remarkably, IFN and IL-12p70 serum levels were lower in A. butzleri-infected TLR-4−/− IL-10−/− versus IL-10−/− mice. In conclusion, TLR-4 is involved in mediating murine A. butzleri infection. Further studies are needed to investigate the molecular mechanisms underlying Arcobacter—host interactions in more detail.

Open access
European Journal of Microbiology and Immunology
Authors: Alex M. Nasaré, Roberto C. Tedesco, Priscila C. Cristovam, Marcos A. Cenedese, Andrés J. Galisteo Jr., Heitor F. Andrade Jr., José Álvaro P. Gomes, Érik V. Guimarães, Helene S. Barbosa, and Luis G. Alonso

HSP90B1 is a gene that codifies heat shock protein 108 (HSP108) that belongs to a group of proteins induced under stress situation, and it has close relation with the nervous system, especially in the retina. Toxoplasma gondii causes ocular toxoplasmosis that has been associated with a late manifestation of the congenital toxoplasmosis although experimental models show that morphological alterations are already present during embryological development. Here, we used 18 eyes of Gallus domesticus embryos in 7th and 20th embryonic days to establish a model of congenital ocular toxoplasmosis, experimentally infected in its fifth day correlating with HSP90B1 gene expression. Embryos’ eyes were histologically evaluated, and gene expression was performed by real-time polymerase chain reaction (PCR). Our data showed parasite present in the choroid, unusual migration of retinal pigment epithelium, and chorioretinal scars, and a tendency to a lower expression of the HSP90B1 gene upon experimental infection. This is a promising model to better understand T. gondii etiopathogeny.

Open access

ESBL (extended-spectrum-β-lactamase)-positive Enterobacteriaceae, which colonized European soldiers in tropical Western African Mali, were subjected to a molecular assessment of their resistance determinants. By doing so, a better insight into the locally endemic pattern of ESBL-associated β-lactamase genes was aspired.

From a previous study on diarrhea in European soldiers on deployment in tropical Mali, 15 ESBL-positive Escherichia coli with demonstrated high clonal diversity and one positive Klebsiella pneumoniae were assessed. Polymerase chain reactions (PCRs) for bla TEM and bla SHV β-lactamase genes with subsequent sequencing for the discrimination of ESBL- and non-ESBL variants were performed, followed by four group-specific PCRs for bla CTX-M genes.

Non-ESBL-associated bla TEM-1 was identified in six out of 15 (40%) E. coli strains, while 100% of the assessed strains were positive for group I bla CTX-M.

Considering the known clonal diversity of the assessed strains, the striking restriction to one group of bla CTX-M genes accounting for the ESBL phenotypes of the isolates suggests little genetic exchange in the local setting. Under such circumstances of restricted numbers of locally endemic target genes, PCR-based screening approaches for ESBL colonization might be promising.

Open access
European Journal of Microbiology and Immunology
Authors: Liliane Kouabla Siransy, Zizendorf Yves Nanga, Flore Sandrine Zaba, Nyasenu Yawo Tufa, and Sery Romuald Dasse

Hepatitis B and HIV infection are two viral infections that represent real global public health problems. In order to improve their management, some hypotheses suggest that genetic predispositions like ABO and Rh blood groups would influence the occurrence of these diseases.

The aim of the present study was to examine the association between ABO and Rhesus blood groups and the susceptibility to HIV infection and hepatitis B.

We conducted a cross-sectional and analytical study in a population of voluntary blood donors in the Blood Transfusion Center of Abidjan. All blood donors who donated blood between January and June 2014 were tested for HBs antigen and anti-HIV antibodies (ELISA tests) and were ABO typed.

The total number of examined blood donors during this period was 45,538, of which 0.32% and 8.07% were respectively infected with HIV and hepatitis B virus. O-group donors were more infected than non-O donors.

Our study is an outline concerning the search for a link between ABO and Rh blood groups and hepatitis B and HIV infection. Further studies should be conducted to confirm the interaction between these two infections and contribute to the search for new therapeutic approaches.

Open access
European Journal of Microbiology and Immunology
Authors: Markus M. Heimesaat, André Fischer, Anja A. Kühl, Ulf B. Göbel, Illana Gozes, and Stefan Bereswill

The octapeptide NAP has been shown to exert neuroprotective properties. Here, we investigated potential anti-inflammatory effects of NAP in an acute ileitis model. To address this, C57BL/6j mice were perorally infected with Toxoplasma gondii (day 0). Within 1 week postinfection (p.i.), placebo (PLC)-treated mice developed acute ileitis due to Th1-type immune responses. Mice that were subjected to intraperitoneal NAP treatment from day 1 until day 6 p.i., however, developed less distinct macroscopic and microscopic disease as indicated by less body weight loss, less distinct histopathological ileal changes, and lower ileal apoptotic, but higher proliferating cell numbers, less abundance of neutrophils, macrophages, monocytes, and T lymphocytes, but higher numbers of regulatory T cells in the ileal mucosa and lamina propria, and lower concentrations of pro-inflammatory mediators in the ilea as compared to PLC controls at day 7 p.i. Remarkably, NAP-mediated anti-inflammatory effects could also be observed in extra-intestinal compartments including liver and spleen. Strikingly, lower MCP-1, TNF, and IL-12p70 serum concentrations in NAP as compared to PLC-treated mice at day 7 p.i. indicate a pronounced systemic anti-inflammatory effect of NAP in acute ileitis. These findings provide first evidence for NAP as a potential novel treatment option in intestinal inflammation.

Open access