Crucial cytokine interactions in nitric oxide production induced by Mycoplasma arthritidis superantigen

Ainsliaea fragrans champ. Extract prevents cervicitis in BALB/c mice and regulates MyD88-NF-κB signaling pathway in MALP-2-stimulated RAW264.7 cells

Ethnopharmacological relevance Ainsliaea fragrans Champ. (A. fragrans) is used to treat infection of the lower genital tract in gynecology, such as cervicitis and pelvic inflammatory disease. This study analyzed the therapeutic efficiency of A. fragrans on cervicitis and the inhibition mechanism of AF-p2 in MALP-2-stimulated RAW264.7 cells. Materials and methods The anti- Ureaplasma urealyticum (Uu) activity of A. fragrans and AF-p2 were determined by antimicrobial susceptibility testing. The activity of A. fragrans extracts (AFext) was evaluated in female BALB/c mice with cervicitis induced by Uu. Furthermore, the therapeutic mechanism of AFext and AF-p2 on myeloid differentiation factor 88 (MyD88) pathway were studied in macrophage activating lipopeptide-2 (MALP-2) irritated RAW264.7 cells. Results AFext could suppress the proliferation of Uu in vitro, including the azithromycin resistant strains. Meanwhile, AFext prevented cervicitis caused by Uu infection in BALB/c mice. Moreover, both AFext and AF-p2 could significantly suppress the nitric oxide (NO) production as well as other proinflammatory cytokines (IL-1β,IL-6,TNF-α) in MALP-2 stimulated RAW264.7 cells. Moreover, AF-p2 also down-regulated iNOS, p65, Iκ-Bα, MyD88 and cyclooxygenase-2 (COX-2) levels in RAW264.7 cells. Conclusion This study indicated that AFext had a therapeutic effect in cervicitis induced by Uu infection. Furthermore, the lead compound AF-p2 showed an anti-infectious effect in MALP-2 irritated RAW264.7 cells through downregulating MyD88-NF-κB signaling pathway.

Clinical characteristics of Kawasaki disease complicated with Mycoplasma pneumoniae pneumonia: A retrospective study

This study aimed to investigate the inner linkage and mechanism of Mycoplasma pneumoniae (MP) infection and Kawasaki disease (KD), as well as the risk factors of outcome in this cohort of patients.A retrospective study was performed in 210 patients diagnosed with KD complicated with community acquired pneumonia (CAP) in Children's Hospital, Zhejiang University School of Medicine from January 2014 to December 2017. They were divided into two groups based on MP infection: MP infection group (n = 97) and non-MP infection group (n = 113). We compared the variables of these two groups based on medical records.The MP infection group had higher ESR than the non-MP infection group. During hospitalization, the non-MP infection group had higher levels of WBC during hospital, LDH, PCT, and lower HB when compared to the MP infection group. No differences were found in the hs-CRP level, N%, PLT, ALT, CKMB, and cytokine levels (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) between MP and non-MP infection group. Likewise, no difference was found in fever duration or hospital stays between them. Totally 19 patients in the infection group had CAA with a rate of 19.59%; and 27 (23.89%) patients had CAA in the non-MP infection group. Unfortunately, no difference was found in CAA rate between the two groups.MP infection may occur simultaneously in children with Kawasaki disease. KD patients with MP infection tended to occur in older population. MP infection may not increase the risk of CAA, which still needs further large-scaled studies to confirm. Clinicians should be alert to KD patients with high level of ESR. MP should be screened and early treatment with macrolides should be given timely.

Kawasaki disease associated with Mycoplasma pneumoniae

BACKGROUND

Kawasaki disease (KD) is an illness of unknown etiology that mostly occurs in children under 5 years of age and is the leading cause of acquired heart disease all over the world. Mycoplasma pneumoniae (MP) was one of the likely causative agents of KD. However, the etiologic effect of MP in KD has not been fully recognized.

METHODS

We prospectively analyzed the clinical records of 450 patients with KD hospitalized in Children's Hospital of Soochow University from 2012 to 2014. Using medical records, we retrospectively identified patients with low respiratory tract infection (non-KD group).

RESULTS

Of the 450 KD patients, MP was positive in 62 (13.8 %). The median age of the MP + KD+ group was significantly older than the MP-KD+ group (25 vs 14.5 months, P < 0.01). MP + KD+ group had higher levels of ESR, N% and CRP than the MP-KD+ group. MP + KD+ group were more frequent in respiratory disorders than MP-KD+ group with a P < 0.05. No statistical difference of non-responders or coronary artery lesion was found between the groups.

CONCLUSIONS

MP infections are found in an important proportion of the KD patients (13.8 % in our series). MP infection tended to occur in older populations and with a higher rate of respiratory tract involvement in patients with KD. No statistical difference of non-responders or coronary artery lesion was found between the MP+ and MP- KD patients.

Evidence of acute Mycoplasma infection in a patient with incomplete and atypical kawasaki disease: a case report

The etiology of Kawasaki disease remains unknown despite extensive studies. Some researchers suggest that it is caused by an infectious agent. This is a case report where a patient with incomplete Kawasaki disease was found to have evidence compatible with acute Mycoplasma pneumoniae infection. This is one of the several case reports linking Mycoplasma pneumoniae to Kawasaki disease as a possible trigger. This is perhaps due to a superantigen or is mediated by some other mechanism. Accurate and timely testing for Mycoplasma infections is difficult and has its limitations. Despite this, Mycoplasma pneumoniae should be considered in the differential and workup for Kawasaki disease.

Mycoplasmal lipid-associated membrane proteins and Mycoplasma arthritidis mitogen recognition by serum antibodies from patients with rheumatoid arthritis

Mycoplasmal lipid-associated membrane proteins (LAMPs) and Mycoplasma arthritidis mitogen (MAM superantigen) are potent stimulators of the immune system. The objective of this work was to detect antibodies to MAM and LAMPs of Mycoplasma hominis and M. fermentans in the sera of patients affected by rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) to identify mycoplasmal products that can be involved in the etiopathogenesis of these autoimmune diseases. Serum samples from female RA and SLE patients and controls, recombinant MAM, and LAMPs of M. hominis PG21 and M. fermentans PG18 were used in Western blot assays. A similar frequency of sera from patients and controls reactive to MAM was detected. A larger number of M. hominis and M. fermentans LAMPs were recognized by sera from RA patients than controls, but no differences were detected between sera from SLE patients and controls. Among the LAMPs recognized by IgG antibodies from RA patients, proteins of molecular masses in a range of <49 and ≥20 KDa (M. hominis) and <102 and ≥58 KDa (M. fermentans) were the most reactive. These preliminary results demonstrate the strong reactivity of antibodies of RA patients with some M. hominis and M. fermentans LAMPs. These LAMPs could be investigated as mycoplasmal antigens that can take part in the induction or amplification of human autoimmune responses.

IL-2 and IFN-gamma in the retina of diabetic rats

BACKGROUND

The pathophysiology of the early events leading to diabetic retinopathy is not fully understood. It has been suggested that Inflammatory processes are involved in the development of the disease; however, the concentrations of tissue retinal inflammatory mediators and their possible alteration in diabetic retinopathy have not been described. The aim of this work was to study T-helper cell cytokine and chemokine profiles, and tyrosine nitration in retinal tissue of diabetic rats.

METHODS

Cytokines (interleukin IL-1a, IL-1b, IL-2, IL-4, IL-6, IL-10, TNFa, GM-CSF, IFN-g), chemokines (MIP-1a, MIP-2, MIP-3a, MCP-1, GRO/KC, RANTES, Fractalkine), and tyrosine nitration were measured in retinal homogenate obtained from Long-Evans rats after 5 months of experimental diabetes.

RESULTS

The T-helper type 1 cytokines IL-2 and INF-gamma, in addition to NO production (measured as nitrotyrosine), were found to be significantly elevated in diabetic rat retina homogenates. None of the other cytokines and chemokines studied were affected by the diabetic condition.

CONCLUSIONS

Immunoregulatory cytokines belonging to the Th-1 group (IL-2 and IFN-gamma) were increased in the retina of experimental diabetic rats. Moreover, the nitrotyrosine formation (as an expression of increased NO production) was significantly elevated in the diabetic retina, supporting the concept of an inflammatory element in the development of diabetic retinopathy.