Mechanism of Infantile Feire Kechuan Oral Solution against Mycoplasma pneumoniae infection of A549 cells.

BACKGROUND: Mycoplasma pneumoniae is a leading cause of community-acquired respiratory infections. Infantile Feire Kechuan Oral Solution (IFKOS) is effective for treatment of M. pneumoniae infection. The aim of this study was to explore the potential mechanism of IFKOS against M. pneumoniae infection in basal epithelial human lung adenocarcinoma A549 cells. METHODS: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to determine the effects of IFKOS on the viability of A549 cells infected with M. pneumoniae. Optical microscopy was used to observe cell morphology and a Muse cell analyzer was used to assess apoptosis and the cell cycle phase. Enzyme-linked immunosorbent assays were employed to assess the expression levels of interleukin (IL)-4, IL-6, IL-8, IL-17, tumor necrosis factor (TNF)-α, interferon (IFN)-α, and IFN-γ. RESULTS: Under certain conditions, M. pneumoniae infection reduced the viability and inhibited the proliferation of A549 cells, promoted early apoptosis, and arrested cells in the G0/G1 phase, thus shortening the S and G2/M phases (all p < 0.05). M. pneumoniae also upregulated expression of IL-8 and TNF-α and downregulated that of IL-6 (p < 0.05), which switched the immune balance of Th1/Th2 to Th1 cells. IFKOS (5.531 mg/mL) improved the viability and proliferation of M. pneumoniae-infected A549 cells, mitigated early apoptosis, and reversed cell cycle arrest in the G0/G1 phase, thereby extending the S and G2/M phases (all, p < 0.05). IFKOS downregulated expression of IL-8 and TNF-α and upregulated that of IL-6 (p < 0.01), thereby reversing the immune imbalance of Th1/Th2. Secretion of IL-4, IL-17, IFN-α, and IFN-γ was not observed. CONCLUSION: IFKOS played a protective role in the regulation of cell viability, apoptosis, the cell cycle, and Th1/Th2 immune imbalance induced by M. pneumoniae infection and conveyed an anti-inflammatory effect in A549 cells.

Dietary Supplementation with Low-Molecular-Weight Fucoidan Enhances Innate and Adaptive Immune Responses and Protects against Mycoplasma pneumoniae Antigen Stimulation.

In this study, the low-molecular-weight (LMW) fucoidan, rich in fucose and sulfate, was extracted and purified from the edible brown seaweed, Laminaria japonica. In this study, we orally administered LMW fucoidan to mice for 6 weeks. We then examined fucoidan's effects on innate immunity, adaptive immunity, and Mycoplasma pneumoniae (MP)-antigen-stimulated immune responses. Our data showed that LMW fucoidan stimulated the innate immune system by increasing splenocyte proliferation, natural killer (NK) cell activity, and phagocytic activity. LMW fucoidan also increased interleukin (IL)-2, IL-4, and interferon (IFN)-γ secretion by splenocytes and immunoglobulin (Ig)-G and IgA content in serum, which help regulate adaptive immune cell functions, and decreased allergen-specific IgE. In MP-antigen-stimulated immune responses, the IgM and IgG content in the serum were significantly higher in the LMW fucoidan group after MP-antigen stimulation. Our study provides further information about the immunomodulatory effects of LMW fucoidan and highlights a potential role in preventing M. pneumoniae infection.

[Effects of Huaiqihuang granules on immune function in children with severe Mycoplasma pneumoniae pneumonia].

OBJECTIVE: To observe the effects of Huaiqihuang granules on the immune function in children with severe Mycoplasma pneumoniae pneumonia. METHODS: Pediatric inpatients with severe Mycoplasma pneumoniae pneumonia were randomly divided into Huaiqihuang granule treatment group (n=51) and conventional treatment group (n=47). The Huaiqihuang granule treatment group was orally administered Huaiqihuang granules in addition to the conventional treatment, while the conventional treatment group received conventional treatment only. Levels of serum IgA, IgG, and IgM, percentages of CD4+ and CD8+ T lymphocyte subsets, and CD4+/CD8+ ratio were examined in the two groups. The incidence rate of respiratory tract re-infection within three months following treatment was compared between the two groups. RESULTS: The levels of serum IgA, IgG, and IgM, the percentage of CD4+ T lymphocytes, and the CD4+/CD8+ ratio were significantly higher in the Huaiqihuang granule treatment group than in the conventional treatment group three months after treatment (P<0.05). In contrast, the percentage of CD8+ T lymphocytes was significantly lower in the Huaiqihuang granule treatment group than in the conventional treatment group (P<0.05). In addition, the incidence rate of respiratory tract re-infection within three months following treatment was significantly lower in the Huaiqihuang granule treatment group than in the conventional treatment group (P<0.05). CONCLUSIONS: Huaiqihuang granules can regulate immune functions and reduce the incidence of short-term respiratory tract re-infection in children with severe Mycoplasma pneumoniae pneumonia.

Transient basal ganglia and thalamic involvement following Mycoplasma pneumoniae infection associated with antiganglioside antibodies.

A case of acute and reversible bilateral basal ganglia with thalami involvement associated with serological evidence of Mycoplasma pneumoniae infection is reported. Increased titers of immunoglobulin M antibodies against GM1 ganglioside components were found during an acute phase of neurological illness. Brain magnetic resonance imaging (MRI) showed bilateral involvement of the basal ganglia and thalamus, which disappeared 1 month later. The child recovered fully after corticosteroid and immunoglobulin therapy, and antiganglioside antibodies returned to within the normal range. The authors speculate on the diagnostic hypothesis regarding selective basal ganglia and thalamic involvement and the relationship with anti-GM1 ganglioside immunoglobulin M antibodies.

Evaluation of LBM415 (NVP PDF-713), a novel peptide deformylase inhibitor, for treatment of experimental Mycoplasma pneumoniae pneumonia.

Mycoplasma pneumoniae is a major cause of community-acquired pneumonia. We evaluated the efficacy of LBM415, a novel peptide deformylase inhibitor antimicrobial agent, for the treatment of M. pneumoniae pneumonia in a mouse model. Eight-week-old BALB/c mice were intranasally inoculated once with 10(7) CFU of M. pneumoniae. Groups of mice were treated with LBM415 (50 mg/kg of body weight) or placebo subcutaneously daily for 13 days, starting 24 h after inoculation. Groups of mice were evaluated at the baseline; at days of treatment 1, 3, 6, and 13; and at 7 days after treatment. The MIC of LBM415 against M. pneumoniae was <0.005 microg/ml. LBM415-treated mice had significantly lower bronchoalveolar lavage fluid M. pneumoniae concentrations than placebo-treated mice on days 6 and 13 of treatment. Compared with placebo treatment, therapy with LBM415 significantly decreased lung histopathology scores at days 3, 6, and 13 of treatment and at 7 days after treatment. Airway obstruction was significantly lower in LBM415-treated mice than in placebo-treated mice on days 1, 3, and 6 of treatment and after 7 days of therapy, while airway hyperresponsiveness was significantly lower only on day 3 of therapy. The bronchoalveolar lavage fluid concentrations of tumor necrosis factor alpha, gamma interferon (IFN-gamma), interleukin-6 (IL-6), IL-12, KC (functional IL-8), monocyte chemotactic protein 1, macrophage inflammatory protein 1alpha, monokine induced by IFN-gamma, and IFN-inducible protein 10 were significantly reduced in LBM415-treated mice compared with the levels in placebo-treated mice. There were no differences in the bronchoalveolar lavage fluid concentrations of granulocyte-macrophage colony-stimulating factor, IL-1beta, IL-2, IL-4, IL-5, and IL-10 between the two groups of mice. LBM415 therapy had beneficial microbiologic, histologic, respiratory, and immunologic effects on acute murine M. pneumoniae pneumonia.

[Study of huchang qingfei pellets on immune function in rats infected with Mycoplasma pneumoniae].

OBJECTIVE: To study the effects and mechanism of Huchang Qingfei pellets on immune function in rats infected with mycoplasma pneumoniae. METHOD: A rat model of mycoplasmal pneumonia (MP) was developed in repeated intranasal infectious routes and then the humoral and cellular immunocompetences were detected by radioimmunoassay, immune-turbidimetry and flow cytometry. RESULT: The levels of serum IgG,IgM and IL-2, IL-6 were enhinced obviously, the complement C3 and TNF-alpha were decreased and the ratio of CD4+ /CD8+ was improved significantly in the Huchang groups as compared with MP model group. CONCLUSION: Huchang Qingfei pellets can reinforce immune function via preventing both cellular and humoral immunity from depression in the rats with MP.

[Effect of selenium on children suffered from Mycoplasma pneumonia].

In order to evaluate the therapeutic effects of Selenium (Se) on Mycoplasma pneumonia, a clinical study was conducted in hospitalized patients using a double blind controlled method. The patients were randomly divided into two groups, the control patients received the routine treatment, and the supplemented group was given 1 mg sodium selenite one time only in addition to the routine treatment. The present study showed that concomitant of Se and routine treatment was superior to routine treatment alone in terms of improvement of clinical signs, time needed for relieving symptoms and signs (P < 0.05). The levels of Se and glutathione peroxidase in plasma and white blood cell were increased in Se supplemented group (P < 0.05). Higher proportion of patients in the treated group showed normalization of T cell subset parameters as compared with the control group. It can be concluded that supplementation of Se would be conducive to the improvement of the nutritional status and the increase of the ability of resisting-infection.

Immune responses to the capsular polysaccharide of Mycoplasma dispar in calves and mice.

Humoral and cell-mediated immune responses to the capsular polysaccharide (CPS) of M. dispar and polygalacturonic acid (pGaIU--a structurally similar polysaccharide) were investigated in calves experimentally infected with Mycoplasma dispar and in mice immunized with CPS or pGaIU. Sera, tracheobronchial lavage and nasal fluids, collected before and after infection in calves, were checked for the presence of anti-CPS and anti-pGaIU antibodies. The sera from mice injected with CPS or pGaIU were checked for different classes of anti-CPS and anti-pGaIU antibodies. Peripheral blood lymphocytes from calves and splenic lymphocytes from mice were monitored for specific proliferative responses to CPS and pGaIU. At about 2 weeks post-infection, anti-CPS IgM response in serum, anti-CPS and anti-pGaIU IgM and IgA response in lavage fluid and lymphocyte proliferative response was seen in the calves. Mice immunized with CPS and pGaIU gave exclusively IgM responses. No secondary response was seen in mice immunized with CPS in contrast to mice immunized with pGaIU. Antibodies cross-reactive with pGaIU were present in the sera of CPS-immunized mice but antibodies cross-reactive with CPS were not found in pGaIU-immunized mice. No significant blastogenic response was shown by mouse splenocytes to CPS or pGaIU.

Protective effect of colostrum in Mycoplasma pneumoniae infection induced in infant mice.

The immunological responses and mechanism of maternal immunity in Mycoplasma pneumoniae infection of mice were investigated. ICR female mice, 4 weeks old, and infant mice, 2 to 4 days old, were infected with M. pneumoniae. Anti-M. pneumoniae antibodies in serum and colostrum were determined by enzyme-linked immunosorbent assay. The specific IgG antibody production persisted for 9 months or longer in both the young and infant mice. These infected mice were protected from rechallenge with M. pneumoniae. In addition, the infected dams conferred passive immunity on their offspring. The infant mice born to uninfected normal dams were protected from the challenge with M. pneumoniae when fed by infected foster dams. Conversely, the infant mice born to infected dams were not protected from the challenge with M. pneumoniae when the infants were fed by uninfected dams. The specific IgG antibody appeared in serum of infant mice inoculated orally with M. pneumoniae-infected mouse serum and the infants were protected from challenge with M. pneumoniae, while the infants given protein A-absorbed serum were not protected from the challenge. These results suggest that one of the factors involved in the resistance of infant mice to M. pneumoniae infection is the specific IgG antibody present in the colostrum rather than the result of transplacental transfer.