RESUMO
Even in asymptomatic cases of Chlamydia trachomatis infection, the aim of the antibiotic strategy is eradication of the pathogen so as to avoid the severe late sequelae, such as pelvic inflammatory disease, ectopic pregnancy, and tubal infertility. Although first-line antimicrobial agents have been demonstrated to be predominantly successful in the treatment of C. trachomatis infection, treatment failures have been observed in some cases. Rich source of antimicrobial peptides was recently discovered in Medicago species, which act in plants as differentiation factors of the endosymbiotic bacterium partner. Several of these symbiotic plant peptides have proved to be potent killers of various bacteria in vitro. We show here that 7 of 11 peptides tested exhibited antimicrobial activity against C. trachomatis D, and that the killing activity of these peptides is most likely due to their interaction with specific bacterial targets.
Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Proteínas de Bactérias/metabolismo , Chaperonina 60/metabolismo , Chlamydia trachomatis/efeitos dos fármacos , Medicago truncatula/química , Proteínas de Plantas/farmacologia , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Proteínas de Bactérias/isolamento & purificação , Chaperonina 60/isolamento & purificação , Chlamydia trachomatis/crescimento & desenvolvimento , Chlamydia trachomatis/metabolismo , Células HeLa , Humanos , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Proteínas de Plantas/síntese química , Proteínas de Plantas/isolamento & purificação , Ligação ProteicaRESUMO
OBJECTIVE: Investigation of the effects of interleukin (IL)-17 cytokines in Chlamydophila pneumoniae-infected mice. METHODS: Mice were infected with C. pneumoniae once or three times and the expression of IL-17 cytokines was followed by RT qPCR from day 1 to day 28 after infection and re-infection. After the treatment of mice with anti-IL-17A, ELISA was used to detect the differences in cytokine and chemokine production. The number and phenotype of the IL-17A-producing cells were determined by ELISPOT. RESULTS: Chlamydophila pneumoniae induced IL-17A and IL-17F from day 2 after infection, and their levels remained elevated on day 28. The expression of IL-17C, IL-17D and IL-17E mRNA did not change significantly in response to a single infection. The in vivo neutralization of IL-17A resulted in a higher C. pneumoniae burden in the mouse lungs, a decreased cell influx, and diminished chemokine levels. The phenotype of IL-17A-producing cells was CD4(+). The re-infection of mice led to an increased expression of IL-17E mRNA. CONCLUSION: These results facilitate an understanding of the early inflammatory response after C. pneumoniae infection and suggest that C. pneumoniae re-infection induces the production of a high amount of IL-17E, which has an important role in the pathogenesis of allergic pulmonary diseases.