Neutralization of Interleukin-9 Decreasing Mast Cells Infiltration in Experimental Autoimmune Encephalomyelitis.

BACKGROUND: Th9 cells are a newly discovered CD4+ T helper cell subtype, characterized by high interleukin (IL)-9 secretion. Growing evidences suggest that Th9 cells are involved in the pathogenic mechanism of multiple sclerosis (MS). Mast cells are multifunctional innate immune cells, which are perhaps best known for their role as dominant effector cells in allergies and asthma. Several lines of evidence point to an important role for mast cells in MS and its animal models. Simultaneously, there is dynamic "cross-talk" between Th9 and mast cells. The aim of the present study was to examine the IL-9-mast cell axis in experimental autoimmune encephalomyelitis (EAE) and determine its interaction after neutralizing anti-IL-9 antibody treatment. METHODS: Female C57BL/6 mice were randomly divided into three groups (n = 5 in each group): mice with myelin oligodendrocyte glycoprotein (MOG)-induced EAE (EAE group), EAE mice treated with anti-IL-9 antibody (anti-IL-9 Abs group), and EAE mice treated with IgG isotype control (IgG group). EAE clinical score was evaluated. Mast cells from central nervous system (CNS) were detected by flow cytometry. The production of chemokine recruiting mast cells in the CNS was explored by reverse transcription-polymerase chain reaction (RT-PCR). In mice with MOG-induced EAE, the expression of IL-9 receptor (IL-9R) complexes in CNS and spleen mast cells was also explored by RT-PCR, and then was repeating validated by immunocytochemistry. In vitro, spleen cells from EAE mice were cultured with anti-IL-9 antibody, and quantity of mast cells was counted by flow cytometry after co-culture. RESULTS: Compared with IgG group, IL-9 blockade delayed clinical disease onset and ameliorated EAE severity (t = -2.217, P = 0.031), accompany with mast cells infiltration decreases (day 5: t = -8.005, P < 0.001; day 15: t = -11.857, P < 0.001; day 20: t = -5.243, P = 0.001) in anti-IL-9 Abs group. The messenger RNA expressions of C-C motif chemokine ligand 5 (t = -5.932, P = 0.003) and vascular cell adhesion molecule-1 (t = -4.029, P = 0.004) were significantly decreased after IL-9 neutralization in anti-IL-9 Abs group, compared with IgG group. In MOG-induced EAE, the IL-9R complexes were expressed in CNS and spleen mast cells. In vitro, splenocytes cultured with anti-IL-9 antibody showed significantly lower levels of mast cells in a dose-dependent manner, compared with splenocytes cultured with anti-mouse IgG (5 µg/ml: t = -0.894, P = 0.397; 10 µg/ml: t = -3.348, P = 0.019; 20 µg/ml: t = -7.639, P < 0.001). CONCLUSIONS: This study revealed that IL-9 neutralization reduced mast cell infiltration in CNS and ameliorated EAE, which might be relate to the interaction between IL-9 and mast cells.

Effects of Naoxintong on atherosclerosis and inducible nitric oxide synthase expression in atherosclerotic rabbit.

BACKGROUND: High levels of nitric oxide (NO) produced by inducible NO synthase (iNOS) have been associated with atherosclerosis processes. Naoxintong is a traditional Chinese medicine for treatment of cerebrovascular and cardiovascular disease. The aim of the present study was to detect and quantify changes of iNOS mRNA and NO levels in the vessel wall after the administration of Naoxintong in an atherosclerotic rabbit model. METHODS: Forty New Zealand white rabbits were randomly divided into five groups (n = 8). Rabbits were fed a standard diet (group A), an atherogenic diet consisting of 79% standard feed + 1% cholesterol + 5% lard + 15% egg yolk powder (group B), an atherogenic diet with Naoxintong 0.25 mg×kg(-1)×d(-1) (group C), an atherogenic diet with Naoxintong 0.5 mg×kg(-1)×d(-1) (group D), or atherogenic diet with Naoxintong 1.0 mg×kg(-1)×d(-1) (group E) for 12 weeks. RESULTS: Supplemented administration of Naoxintong led to a down-regulation of cholesterol (CHOL) (P < 0.001) and low-density lipoprotein (LDL) (P < 0.001). The trend became more notable as the dose of Naoxintong increased; group C vs. group B (CHOL, P = 0.568; LDL-cholesterol (LDL-C), P = 0.119), group D vs. group B (CHOL, P = 0.264; LDL-C, P = 0.027), group E vs. group B (CHOL, P = 0.028; LDL-C, P = 0.002). Atherosclerotic lesions in aorta were reduced in Naoxintong groups (groups C, D, E) compared to group B. Group B had higher iNOS mRNA (P = 0.001) and NO level (P < 0.001) than group A. Compared with the atherogenic diet fed-rabbits, Naoxintong supplements decreased the expression of iNOS mRNA (P < 0.001) and the NO level (P < 0.001) in the vessel wall. Groups given a higher Naoxintong dose exhibited greater benefits. iNOS mRNA and NO levels seemed to be reduced in group C, although the difference did not quite reach statistical significance (iNOS mRNA, P = 0.130; NO, P = 0.038). iNOS mRNA and NO levels significantly decreased in group D (iNOS mRNA, P = 0.019; NO, P = 0.018) and group E (iNOS mRNA, P = 0.004; NO, P < 0.001). CONCLUSION: Naoxintong has beneficial effects on atherosclerosis treatment by reducing expression of iNOS mRNA and the NO level in the vessel wall.

Relationship between neuromyelitis optica-IgG status and spinal cord magnetic resonance imaging in patients with neuromyelitis optica.

BACKGROUND: Despite the large scale technical innovations that have been made, a number of patients with neuromyelitis optica (NMO) are lacking NMO-IgG in both serum and cerebrospinal fluid. Longitudinally extensive spinal cord (LESC) lesions and linear lesions are associated with NMO. However, differences of spinal cord magnetic resonance imaging (MRI) features, including LESC lesions and linear lesions, between NMO-IgG positive and negative patients still remain unknown. The aim of the present study was to analyze the relationship between NMO-IgG status and spinal cord MRI features in NMO patients, particularly concerned about LESC lesions and linear lesions. METHODS: Clinical data and spinal cord MRI of 52 NMO patients were retrospectively analyzed. Eight patients were NMO-IgG negative in both serum and cerebrospinal fluid, while 44 were NMO-IgG positive. Quantitative data between the two cohorts were compared by the Student's t test or Mann-Whitney U test, the chi-square test or Fisher's exact test was used to evaluate qualitative data. RESULTS: NMO-IgG negative patients had a higher sex ratio (male/female) (P = 0.014). On axial MRI, lesions in the NMO-IgG negative group were mostly located in the peripheral cord (50%), and central lesions (55%) were more common in the NMO-IgG positive group (P = 0.051). LESC lesions were common in both cohorts. None of linear lesions was found in NMO-IgG negative patients, while the NMO-IgG positive cohort had significantly more linear lesions (48%) (P = 0.016). CONCLUSIONS: Patients with NMO-IgG negativity may have different spinal cord lesion features compared to NMO-IgG positive patients. Diagnosis of NMO cannot be excluded even when NMO-IgG negativity and non-specific spinal lesions occur.