The effect of adipose stem cell therapy on pulmonary fibrosis induced by repetitive intratracheal bleomycin in mice.

Adipose stem cells (ASCs) are detectable in the parenchyma and large airways of lungs after systemic administration, and ameliorate inflammatory infiltration and cell death in animal models of emphysema. We evaluated whether ASC treatment could attenuate lung fibrosis induced by repetitive intratracheal bleomycin administration. Male 8-week-old C57BL/6J mice (control group, bleomycin-only group, and bleomycin-plus-ASC group) were used. Eight biweekly doses of bleomycin were injected intratracheally via an intubation procedure at a dose of 0.04 units in a total volume of 100 µL of sterile saline. During the latter 2 months of the 4-month bleomycin exposure, human ASCs (3 × 10(5) cells) were administered repeatedly via intraperitoneal injection at the same time as bleomycin. Lung tissues were evaluated for histology, collagen content, TUNEL staining, and TGF-ß levels. Bronchoalveolar lavage (BAL) was performed for cell counting. Administrations of ASCs ameliorated the deleterious effects of repetitive intratracheal instillation of bleomycin, namely hyperplasia of Club cells (Clara cells) and cuboidal alveolar epithelial cells, infiltration of the perialveolar ducts by inflammatory cells, septal thickening, enlarged alveoli, and extensive fibrosis. Addition of ASC led to suppression of bleomycin-induced epithelial cell apoptosis and expression of TGF-ß. These results suggest a useful therapeutic effect of ASCs on pulmonary fibrosis induced by repetitive bleomycin administration. Further studies will be required to evaluate the efficacy of ASC therapy for the treatment of idiopathic pulmonary fibrosis.

The attenuation of cockroach allergy by DNA vaccine encoding cockroach allergen Bla g 2.

Bla g 2 is one of the most potent cockroach allergens. No effective treatment or vaccination strategies are yet available. We evaluated the prophylactic efficacy of Bla g 2 DNA vaccination in a mouse model of allergic airway inflammation. C57/BL6 mice were given Bla g 2 DNA vaccine prior to sensitization with recombinant Bla g 2 (rBla g 2) antigens, followed by nebulized rBla g 2 challenge. Bla g 2 vaccine could express at both transcriptional and translational levels in mammalian cells. Moreover, Bla g 2 vaccine significantly reduced the total inflammatory cell infiltrate and eosinophilia in bronchoalveolar lavage fluid, and markedly decreased allergen-induced inflammatory infiltrates in the lungs and Bla g 2-specific IgE in serum upon challenge with rBla g 2. Importantly, Bla g 2 vaccine could induce the production of antigen-specific IFN-γ and downregulated Th2 pro-inflammatory cytokines IL-4, IL-5, and IL-13. Thus, DNA vaccination showed protective efficacy against a clinically relevant allergen, Bla g 2.

Anti-Inflammatory Gene Therapy Improves Spatial Memory Performance in a Mouse Model of Alzheimer's Disease.

The immune system plays a critical role in neurodegenerative processes involved in Alzheimer's disease (AD). In this study, a gene-based immunotherapeutic method examined the effects of anti-inflammatory cellular immune response elements (CIREs) in the amyloid-ß protein precursor (AßPP) mouse model. Bi-monthly intramuscular administration, beginning at either 4 or 6 months, and examined at 7.5 through 16 months, with plasmids encoding Interleukin (IL)-10, IL-4, TGF-ß polynucleotides, or a combination thereof, into AßPP mice improved spatial memory performance. This work demonstrates an efficient gene therapy strategy to downregulate neuroinflammation, and possibly prevent or delay cognitive decline in AD.

The therapeutic efficacy of human adipose tissue-derived mesenchymal stem cells on experimental autoimmune hearing loss in mice.

Autoimmune inner ear disease is characterized by progressive, bilateral although asymmetric, sensorineural hearing loss. Patients with autoimmune inner ear disease had higher frequencies of interferon-γ-producing T cells than did control subjects tested. Human adipose-derived mesenchymal stem cells (hASCs) were recently found to suppress effector T cells and inflammatory responses and therefore have beneficial effects in various autoimmune diseases. The aim of this study was to examine the immunosuppressive activity of hASCs on autoreactive T cells from the experimental autoimmune hearing loss (EAHL) murine model. Female BALB/c mice underwent ß-tubulin immunization to develop EAHL; mice with EAHL were given hASCs or PBS intraperitoneally once a week for 6 consecutive weeks. Auditory brainstem responses were examined over time. The T helper type 1 (Th1)/Th17-mediated autoreactive responses were examined by determining the proliferative response and cytokine profile of splenocytes stimulated with ß-tubulin. The frequency of regulatory T (Treg) cells and their suppressive capacity on autoreactive T cells were also determined. Systemic infusion of hASCs significantly improved hearing function and protected hair cells in established EAHL. The hASCs decreased the proliferation of antigen-specific Th1/Th17 cells and induced the production of anti-inflammatory cytokine interleukin-10 in splenocytes. They also induced the generation of antigen-specific CD4(+) CD25(+) Foxp3(+) Treg cells with the capacity to suppress autoantigen-specific T-cell responses. The experiment demonstrated that hASCs are one of the important regulators of immune tolerance with the capacity to suppress effector T cells and to induce the generation of antigen-specific Treg cells.

Administering human adipose-derived mesenchymal stem cells to prevent and treat experimental arthritis.

Rheumatoid arthritis is a chronic autoimmune disease and affecting approximately 1% of the population. Human adipose-derived mesenchymal stem cells (hASCs) were recently found to suppress effector T cell and inflammatory responses and, thus, to have beneficial effects in various autoimmune diseases. In this study, we examined whether hASCs could play a protective and/or therapeutic role in collagen-induced arthritis (CIA). We showed that hASCs both prevented and treated CIA by significantly reducing the incidence and severity of experimental arthritis. We further demonstrated that treatment with hASCs inhibited the production of various inflammatory mediators, decreased antigen-specific Th1/Th17 cell expansion, and induced the production of anti-inflammatory cytokine interleukin-10. Moreover, hASCs could induce the generation of antigen-specific Treg cells with the capacity to suppress collagen-specific T cell responses.

Murine autoimmune hearing loss mediated by CD4+ T cells specific for ß-tubulin.

Autoimmune inner ear disease is described as progressive, bilateral although asymmetric, sensorineural hearing loss and can be improved by immunosuppressive therapy. We showed that the inner ear autoantigen ß-tubulin is capable of inducing experimental autoimmune hearing loss (EAHL) in mice. Immunization of BALB/c mice with ß-tubulin resulted in hair cell loss and hearing loss, effects that were not seen in animals immunized with control peptide. Moreover, the EAHL model showed that ß-tubulin responsiveness involved CD4(+) T cells producing IFN-γ, and T cell mediation of EAHL was determined by significantly increased auditory brainstem response after adoptive transfer of ß-tubulin-activated CD4(+) T cells into naive BALB/c recipients. The potential mechanisms responsible for the observed pathology of EAHL can be attributed to decreased frequency and impaired suppressive function of regulatory T cells. Our study suggests that EAHL may be a T cell-mediated organ-specific autoimmune disorder of the inner ear.

ENU induced single mutation locus on chr 16 leads to high-frequency hearing loss in mice.

The hallmark of age-related (presbycusis) and noise-induced hearing loss is high-frequency (> 20 kHz) hearing loss. Through a collaborative study with TMGC (Tennessee Mouse Genome Consortium), seventeen ENU-induced mouse mutation strains with high-frequency hearing loss have been identified, but affected genes are yet identified. As a first step in identifying the gene/s underlying the ENU mutations, we created a F2 population between a representative mutation strain, 118 TNE and a wild type strain, CAST/EJ (CAST). Phenotypic analysis showed that there is a 3:1 ratio of segregation between normal and hearing loss in the F2 population, suggestion a single locus regulation. However, the linkage mapping identified 2 QTLs, each on chromosomes 15 and 16. Further statistical analysis of marker segregation patterns revealed that the locus on Chr 16 was ENU induced while the one on Chr 15 was derived from the parental strain, CAST.

Identification of 17 hearing impaired mouse strains in the TMGC ENU-mutagenesis screen.

The Tennessee Mouse Genome Consortium (TMGC) employed an N-ethyl-N-nitrosourea (ENU)-mutagenesis scheme to identify mouse recessive mutants with hearing phenotypes. We employed auditory brainstem responses (ABR) to click and 8, 16, and 32 kHz stimuli and screened 285 pedigrees (1819 mice of 8-11 weeks old in various mixed genetic backgrounds) each bred to carry a homozygous ENU-induced mutation. To define mutant pedigrees, we measured > or = 12 mice per pedigree in > or = 2 generations and used a criterion where the mean ABR threshold per pedigree was two standard deviations above the mean of all offspring from the same parental strain. We thus identified 17 mutant pedigrees (6%), all exhibiting hearing loss at high frequencies (> or = 16 kHz) with an average threshold elevation of 30-35 dB SPL. Interestingly, four mutants showed sex-biased hearing loss and six mutants displayed wide range frequency hearing loss. Temporal bone histology revealed that six of the first nine mutants displayed cochlear morphological defects: degeneration of spiral ganglia, spiral ligament fibrocytes or inner hair cells (but not outer hair cells) mostly in basal turns. In contrast to other ENU-mutagenesis auditory screens, our screen identified high-frequency, mild and sex-biased hearing defects. Further characterization of these 17 mouse models will advance our understanding of presbycusis and noise-induced hearing loss in humans.

Protective effect of the DNA vaccine encoding the major house dust mite allergens on allergic inflammation in the murine model of house dust mite allergy.

BACKGROUND: Vaccination with naked DNA encoding antigen induces cellular and humoral immunity characterized by the activation of specific Th1 cells. OBJECTIVE: To evaluate the effects of vaccination with mixed naked DNA plasmids encoding Der p 1, Der p 2, Der p 3, Der f 1, Der f 2, and Der f 3, the major house dust mite allergens on the allergic inflammation to the whole house dust mites (HDM) crude extract. METHODS: Three hundred micrograms of these gene mixtures were injected into muscle of BALB/c mice. Control mice were injected with the pcDNA 3.1 blank vector. After 3 weeks, the mice were actively sensitized and inhaled with the whole house dust mite extract intranasally. RESULTS: The vaccinated mice showed a significantly decreased synthesis of total and HDM-specific IgE compared with controls. Analysis of the cytokine profile of lymphocytes after challenge with HDM crude extract revealed that mRNA expression of interferon-gamma was higher in the vaccinated mice than in the controls. Reduced infiltration of inflammatory cells and the prominent infiltration of CD8+ T cells were observed in histology of lung tissue from the vaccinated mice. CONCLUSION: Vaccination with DNA encoding the major house dust mite allergens provides a promising approach for treating allergic responses to whole house dust mite allergens.

Morphological and functional alterations of the cochlea in apolipoprotein E gene deficient mice.

The relationship between hyperlipidemia and sensorineural hearing loss remains obscure. In this study, we elucidate for the first time the cochlear morphological and auditory alterations and their relationships with hyperlipidemia, atherosclerosis, and endothelial dysfunction in apolipoprotein-E knockout (ApoE-KO) mice. Ten-week-old ApoE-KO mice were fed either atherosclerotic diet (1.25% cholesterol) or normal diet. Wild type mice (C57BL/6J) served as normal controls. Fourteen weeks later, marked hyperlipidemia, atherosclerosis, endothelial dysfunction, and hearing impairment, especially in the high frequencies, had developed in ApoE-KO mice as compared with C57BL/6J mice (P<0.001). A high positive correlation between hearing loss and the extent of atherosclerosis and plasma total cholesterol levels was found. Hearing loss, especially at high frequencies, was detected in all ApoE-KO mice. Hair cell loss mainly at the base turn, thickening of vascular intima, and lumen stenosis of the spiral modiolar artery (SMA) in cochlea were also found; these histological changes were exacerbated by the atherosclerotic diet. Furthermore, endothelial nitric oxide synthase (eNOS) in aortic wall and cochlea was distinctly reduced in ApoE-KO mice. These results demonstrate that hyperlipidemia and atherosclerosis can induce alterations in cochlear morphology and function. The stenosis of SMA, which may cause cochlear ischemia and hypoxia, endothelial dysfunction, and low eNOS activity, may contribute to hearing loss.

Is interstitial cystitis an allergic disorder?: A case of interstitial cystitis treated successfully with anti-IgE.

Interstitial cystitis (IC) is a chronic disorder diagnosed by symptomatology of pelvic pain and urinary frequency, which are extremely variable and unpredictable fluctuating among patients. IC has recently been found combined with some allergic disorders and histopathologic abnormalities resembling that of allergic disorders, including mast cell activation, histamine release and eosinophil infiltration. Therefore, it could be cautiously postulated that IC is one of the allergic disorders of the urogenital system. A 28-year-old Caucasian female patient, who was diagnosed with asthma and allergic rhinitis, suffered from bladder symptoms of frequency, urgency and pelvic pain for the past 3 years. The symptoms disturbed her every day and were intractable for treatment. Urologists concluded that she had interstitial cystitis. Specific immunotherapy (SIT) was recommended for her allergic symptoms. While taking specific immunotherapy, she had anaphylaxis. She still had the reaction even with the 1000-fold diluted shot of SIT. Omalizumab was used for her allergic symptoms and possible prevention of anaphylactic reaction to SIT. Interestingly, she reported that her urogenital symptoms had subsided since omalizumab had been started. According to the published literature, we postulate that interstitial cystitis might be one of the IgE mediated, mast cell driven allergic disorders of the urogenital system. Therefore, in this case, the patient's bladder symptoms are successfully controlled primarily by anti-IgE therapy and the improvement could be maintained by SIT. We report, for the first time, a case of interstitial cystitis with allergic rhinitis and asthma, successfully treated by anti-IgE therapy and specific immunotherapy.

Vaccination with DNA encoding human T-cell epitopes suppresses Der p induced allergic responses in mice.

The apparent complexity of allergen-specific T-cell response in terms of epitope usage in humans is a potential barrier to peptide-based immunotherapy for allergy. A knowledge of cross-reacting T-cell epitopes of common allergens might have an impact on the development of vaccines for immunotherapy. We examined the efficiency of vaccinating with plasmid DNA coding only human T-cell epitopes on the suppression of allergic reactions in mice. BALB/c mice that received an injection of mixed naked DNA plasmids encoding the five classes of human T-cell epitopes on Der p 1 and Der p 2 produced a significant reduction in total and Der p-specific immunoglobulin E (IgE) synthesis. In Der p specific-IgG2a antibody responses, vaccinated mice showed more prominent responses than controls. Higher levels of interferon-gamma, a Th1 cytokine associated with the suppression of IgE production, were found in the sera of vaccinated mice. Histologic studies showed a marked reduction in the infiltration of inflammatory cells in the lung tissues of vaccinated mice vs. controls. These results suggest that vaccination with DNA encoding human T-cell epitopes effectively inhibits allergic responses in mice and might induce cross-regulation on helper T-cell level in vivo.