Chlamydia pneumoniae-induced tumour necrosis factor alpha responses are lower in children with asthma compared with non-asthma

Therapeutic Efficacy of Weissella cibaria CMU and CMS1 on Allergic Inflammation Exacerbated by Diesel Exhaust Particulate Matter in a Murine Asthma Model

Background and Objectives: Diesel exhaust particulate matter (DEPM) is an air pollutant that is associated with asthma. In this study, the therapeutic efficacy of Weissella cibaria strains CMU (Chonnam Medical University) and CMS (Chonnam Medical School) 1, together with the drug Synatura, an anti-tussive expectorant, was investigated in a murine asthma model exacerbated by DEPM. Materials and Methods: BALB/c mice were sensitized with ovalbumin (OVA) before intranasal challenge with OVA and DEPM. W. cibaria CMU, CMS1, and Synatura were administered orally for 21 days. Results: Neither Synatura nor W. cibaria strains affected spleen, liver, or lung weights. W. cibaria strains CMU and CMS1 significantly reduced the levels of interleukin (IL)-4, OVA-specific immunoglobulin E (IgE), and total lung collagen in bronchoalveolar lavage fluid (BALF), similar to those with Synatura, regardless of the oral dose concentration (p < 0.05). In addition, the W. cibaria CMU strain significantly alleviated IL-1β, IL-6, IL-12, monocyte chemotactic protein-1, and tumor necrosis factor-α in BALF, whereas the CMS1 strain significantly alleviated IL-10 and IL-12 in BALF (p < 0.05); however, Synatura did not show any statistical efficacy against them (p > 0.05). All concentrations of W. cibaria CMU and low concentrations of W. cibaria CMS1 significantly reduced lung bronchiolar changes and inflammatory cell infiltration. Conclusions: In conclusion, W. cibaria CMU in asthmatic mice showed better efficacy than W. cibaria CMS1 in improving asthma exacerbated by DEPM exposure, as well as better results than pharmaceuticals.

Beneficial Immunomodulatory Effects of Fluticasone Propionate in Chlamydia pneumoniae-Infected Mice

The associations between inhaled corticosteroid (ICS) use and pulmonary infections remains controversial. Chlamydia pneumoniae (C. pneumoniae) accounts for asthma exacerbations; however, there are no data regarding ICS effects on C. pneumoniae infections. Thus, we investigated whether fluticasone propionate (FP) or budesonide (BUD) could affect C. pneumoniae infection in vitro and in vivo, focusing on the possible mechanisms that lead to potential anti-chlamydial outcomes. We performed direct qPCR to detect C. pneumoniae growth in infected, FP-treated, and BUD-treated A549 cells. Furthermore, FP or BUD was administered by inhalation to C. pneumoniae-infected mice. The recoverable C. pneumoniae was determined by indirect immunofluorescence. Expression levels of interferon (IFN)-γ and IFN-γ inducible chemokines were assessed by qPCR. We measured the protein concentrations of IFN-γ and of other cytokines that potentially participate in the anti-chlamydial response by ELISA. We found that FP treatment suppressed Chlamydia growth in A549 cells and in mice. Higher levels of IFN-γ gene expression were observed in FP-treated mice compared to the untreated and BUD-treated mice (p < 0.0001). IFN-γ and anti-chlamydial protein MIG/CXCL9 values were significantly higher after FP inhalation. Collectively, FP, but not BUD, suppressed C. pneumoniae growth in vitro and in vivo, which was likely due to the enhanced IFN-γ related responses.

[Role of tumor necrosis factor-α in Chlamydia Muridarum infection in the urogenital tract of mice]

OBJECTIVE

To explore the role of tumor necrosis factor-α (TNF-α) in immune response to urogenital chlamydial infection and urogenital pathology in mice.

METHODS

Fifteen female wild-type (WT) C57BL/6J mice and 15 TNF-α receptor knockout (TNF-αR KO) mice were inoculated intravaginally with 1×104 inclusion forming units (IFUs) of live C. muridarum. At 56 days after the first inoculation, 8 mice from each group were subjected to a second inoculation at the same dose. Vaginal swabs were taken every 3 or 4 days to detect the number of inclusion bodies of chlamydia. On day 80 after the first inoculation, the mice were euthanized and peritoneal macrophages were collected and the vaginal tract and spleen were dissected. The pathologies in the fallopian tube and the uterine horn were observed and the severity of inflammatory cell infiltration and lumen dilatation were semi-quantitatively scored. The levels of interleukin-6 (IL-6), IL-8, IL-1α, IL-1β and TNF-α in the supernatant of the peritoneal macrophage were detected. Spleen cell suspension was prepared, and after stimulation with chlamydia EB in vitro, the levels of the cytokines including IL-4, IL-5, IL-17 and interferon-γ (IFN-γ) were determined in the cells.

RESULTS

The clearance rate of Chlamydia from the urogenital tract was similar between TNF-αR KO mice and WT mice regardless of the primary or second infection. The severity of inflammation in the fallopian tube and the uterine horn did not differ significantly between the two groups, but TNF-αR KO mice had significantly milder dilation of the fallopian tubes (P < 0.05). The peritoneal macrophages from TNF-αR KO mice produced a significantly higher level of TNF-α than those from WT mice (P < 0.05); the spleen cells from the two groups both produced high levels of IFN-γ, but IL-17 production by the spleen cells was significantly lower in TNF-αR KO mice than in WT mice (P < 0.05).

CONCLUSIONS

TNF-α is not associated with protective immune response against C. muridarum infection, and can worsen the inflammatory damages of the urogenital tract caused by C. muridarum in mice.

Chlamydia pneumoniae Influence on Cytokine Production in Steroid-Resistant and Steroid-Sensitive Asthmatics

Medications for asthma management consisting of inhaled corticosteroids act by controlling symptoms. However, some patients do not respond to steroid treatment due to immunological factors at the cytokine level. Chlamydia pneumoniae (C. pneumoniae) infection is strongly implicated in asthma pathogenesis, causing altered immune responses. We investigated the association of C. pneumoniae serostatus with the production of certain cytokines by peripheral blood mononuclear cells (PBMCs) of steroid-resistant and -sensitive asthmatic patients. Our most important findings are the following: In the case of C. pneumoniae seropositive patients we detected pronounced spontaneous interleukin (IL)-10 secretion and, in the case of steroid-resistant patients, IL-10 secretion was at a significantly higher level as compared with in-sensitive patients (p < 0.01). Furthermore, steroid-resistant seropositive patients produced a significantly higher level of IL-10 spontaneously and under antigen stimulation as compared with steroid-resistant seronegative individuals (p < 0.05). Concerning spontaneous TNF-α secretion by C. pneumoniae seropositive asthmatics, we observed that steroid-resistant patients produced significantly more of this cytokine than steroid-sensitive patients. In the steroid-resistant patients’ sera, a remarkably high MMP-9 concentration was associated with C. pneumoniae seronegativity. Our study revealed that the differences in the cytokine production in steroid-sensitive and -resistant asthmatic patients can be influenced by their C. pneumoniae serostatus.