ABSTRACT
BACKGROUND: The current study was conducted to investigate the antigenic effect of Marshallagia marshalli on the treatment of asthma by measuring the secreted inhibitory cytokine. METHODS: Case patients and controls were selected from clinics in Mashhad, Khorasan Razavi Province, Northeastern Iran in 2017-18. In this experimental study, peripheral blood mononuclear cells (PBMCs) were isolated from 15 patients with asthma and 10 healthy controls and were cultured. PBMCs were then converted to tolerogenic DCs through exposure to GM-CSF, IL-4 and M. marshalli antigen. Then, tolerogenic DCs were exposed to autologous T cells for five days and finally, the level of secreted TGF-ß1 was measured. RESULTS: The mean TGF-ß1 level in the control and control groups was 210.2 ± 8.2 and 225.4 ± 6.1 pq/ml, respectively. The results showed that TGF-ß1 levels in both groups significantly increased in both groups (P<0.001). In addition, TGF-ß1 levels in the case group were significantly higher than the control group (P<0.001). CONCLUSION: M. marshalli antigen increase the level of TGF-ß1 and can create antigen-bearing dendritic cells and shift T lymphocytes to the regulatory type. This parasite can be used in dendritic cell therapy to control allergic diseases.
ABSTRACT
AIM: This case-control study investigated the various PAI markers, phylogenetic groups and antimicrobial susceptibility among DEC and commensal E. coli isolates. BACKGROUND: Diarrheagenic Escherichia coli (DEC) is an emerging agent among pathogens that cause diarrheal diseases and represents a major public health problem in developing countries. The major difference in virulence among DEC pathotype and commensals may be related to the presence of specific genomic segments, termed pathogenicity islands (PAIs). PATIENTS AND METHODS: A total of 600 stool specimens from children (450 with and 150 without diarrhea) were collected and various PAI markers, phylogenetic groups and antimicrobial resistance profile among DEC and commensal E. coli isolates were detected. RESULTS: One hundred sixty eight (90.3%) isolates were resistant to one or more antimicrobial agents. PAI markers were detected in a substantial percentage of commensal (90%) and DEC isolates (99.3%) (P> 0.05). The most prevalent PAI marker among DEC and commensal isolates was HPI (91.9% DEC vs. 68% commensal). We found a high number of PAI markers such as SHI-2, She and LEE that were significantly associated with DEC. Several different combinations of PAIs were found among DEC isolates. Comparison of PAIs among DEC and commensal isolates showed that many DEC isolates (94.8%) carried two or more PAI markers, while 76% of commensals had only one PAI marker (P<0.05). According to the phylogenetic classification, group B2 was the most commonly found in the DEC isolates. Furthermore, our results showed that group B2 can be present in commensal isolates (18%). CONCLUSION: These results indicate that PAI markers are widespread among commensal and DEC isolates and these commensal isolates may be reservoirs for transmission of these markers.
