Expression of Toll-like receptor 2 in duodenal biopsies from dogs with inflammatory bowel disease is associated with severity of disease

There is growing evidence that aberrant innate immune responses towards the bacterial flora of the gut play a role in the pathogenesis of canine inflammatory bowel disease (IBD). Toll-like receptors (TLR) play an important role as primary sensors of invading pathogens and have gained significant attention in human IBD as differential expression and polymorphisms of certain TLR have been shown to occur in ulcerative colitis (UC) and Crohn's disease (CD). The aim of the current study was to evaluate the expression of two TLR important for recognition of commensals in the gut. TLR2 and TLR4 mRNA expression in duodenal biopsies from dogs with IBD was measured and correlated with clinical and histological disease severity. Endoscopic duodenal biopsies from 20 clinical cases and 7 healthy control dogs were used to extract mRNA. TLR2 and TLR4 mRNA expression was assessed using quantitative real-time PCR. TLR2 mRNA expression was significantly increased in the IBD dogs compared to controls, whereas TLR4 mRNA expression was similar in IBD and control cases. In addition, TLR2 mRNA expression was mildly correlated with clinical severity of disease, however, there was no correlation between TLR2 expression and histological severity of disease.

Treatment of clinically diagnosed equine sarcoid with a mistletoe extract (Viscum album austriacus)

BACKGROUND: Equine sarcoids (ES) are common, difficult to treat, and have high recurrence rates. Viscum album extracts (VAE) are used in human cancer treatment. HYPOTHESIS: That therapy with VAE (Iscador P) is effective in the treatment of ES. ANIMALS: Fifty-three horses (444 ES); 42 were treated with VAE or placebo as monotherapy; 11 were treated with VAE or placebo after selective excision of ES. METHODS: Prospective, randomised, blinded, clinical trial. Horses were randomly assigned to treatment (VAE; n=32) or control group (Placebo; n=21). One milliliter of VAE (Iscador P) in increasing concentrations from 0.1 to 20 mg/mL or physiological NaCl solution was given SC 3 times a week over 105 days. Number, localization, and type of the ES were documented over 12 months. A subset of 163 clinically diagnosed equine sarcoid (CDES) lesions (95 VAE, 68 Placebo) was evaluated in detail, considering clinical findings and tumor volume. RESULTS: No undesired adverse effects were observed except for mild edema at the injection site in 5 of 32 horses (16%). Complete or partial regression was observed in 13 horses of the VAE group (41%) and in 3 of the control horses (14%; P<.05). After VAE treatment, 48 of 95 CDES (67%) showed an improvement compared with 17 of 68 CDES in the control group (40%; P<.01). Twenty-seven CDES had disappeared completely in the VAE group (38%) compared with 9 CDES in the control group (13% NS). CONCLUSIONS AND CLINICAL IMPORTANCE: VAE (Iscador P) represents a safe and effective treatment for CDES.

Equine insect bite hypersensitivity: immunoblot analysis of IgE and IgG subclass responses to Culicoides nubeculosus salivary gland extract

Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by IgE-mediated reactions to bites of Culicoides and sometimes Simulium spp. The allergens causing IBH are probably salivary gland proteins from these insects, but they have not yet been identified. The aim of our study was to identify the number and molecular weight of salivary gland extract (SGE) proteins derived from Culicoides nubeculosus which are able to bind IgE antibodies (ab) from the sera of IBH-affected horses. Additionally, we sought to investigate the IgG subclass (IgGa, IgGb and IgGT) reactivity to these proteins. Individual IgE and IgG subclass responses to proteins of C. nubeculosus SGE were evaluated by immunoblot in 42 IBH-affected and 26 healthy horses belonging to different groups (Icelandic horses born in Iceland, Icelandic horses and horses from different breeds born in mainland Europe). Additionally, the specific antibody response was studied before exposure to bites of Culicoides spp. and over a period of 3 years in a cohort of 10 Icelandic horses born in Iceland and imported to Switzerland. Ten IgE-binding protein bands with approximate molecular weights of 75, 66, 52, 48, 47, 32, 22/21, 19, 15, 13/12 kDa were found in the SGE. Five of these bands bound IgE from 50% or more of the horse sera. Thirty-nine of the 42 IBH-affected horses but only 2 of the 26 healthy horses showed IgE-binding to the SGE (p<0.000001). Similarly, more IBH-affected than healthy horses had IgGa ab binding to the Culicoides SGE (19/22 and 9/22, respectively, p<0.01). Sera of IBH-affected horses contained IgE, IgGa and IgGT but not IgGb ab against significantly more protein bands than the sera of the healthy horses. The cohort of 10 Icelandic horses confirmed these results and showed that Culicoides SGE specific IgE correlates with onset of IBH. IBH-affected horses that were born in Iceland had IgGa and IgGT ab (p< or =0.01) as well as IgE ab (p=0.06) against a significantly higher number of SGE proteins than IBH-affected horses born in mainland Europe. The present study shows that Culicoides SGE contains at least 10 potential allergens for IBH and that IBH-affected horses show a large variety of IgE-binding patterns in immunoblots. These findings are important for the future development of a specific immunotherapy with recombinant salivary gland allergens.

The butterbur extract petasin has no effect on skin test reactivity induced by different stimuli: a randomized, double-blind crossover study using histamine, codeine, methacholine, and aeroallergen solutions

BACKGROUND: Petasin (Ze 339) was recently introduced on the market as a potent herbal antiallergic drug for treatment of respiratory allergies such as hay fever. Few clinical studies have been performed so far addressing the clinical effectiveness of Ze 339. OBJECTIVE: To evaluate the antiallergic properties of Ze 339 using skin prick tests with different stimuli, such as codeine, histamine, methacholine, and a relevant inhalant allergen. METHODS: A randomized, double-blind, placebo-controlled study was performed in which Ze 339 was compared to acrivastine, a short-acting antihistamine, in 8 patients with respiratory allergy and in 10 nonatopic, healthy volunteers. Antiallergic activity of Ze 339 was determined by analyzing inhibitory potency in skin prick tests with codeine, histamine, methacholine, and an inhalant allergen. Wheal-and-flare reactions were assessed 90 minutes after a double dose of Ze 339, acrivastine, or placebo. An interval of at least 3 days was left between the skin tests. RESULTS: Acrivastine was identified as the only substance that significantly inhibited skin test reactivity to all solutions analyzed in all study subjects. In contrast, no significant inhibition could be demonstrated for Ze 339 with any test solution. Moreover, the results of Ze 339 did not differ significantly from placebo. CONCLUSIONS: In this study we found no antiallergic, particularly antihistaminic, effect of Ze 339 in skin tests using a variety of stimuli often used to evaluate immediate skin test reactivity. The mechanism by which Ze 339 is effective in the treatment of seasonal allergic rhinitis still needs to be elucidated.

Decreasing gut wall glucose as an early marker of impaired intestinal perfusion

OBJECTIVE: The aim of this study was to assess the microcirculatory and metabolic consequences of reduced mesenteric blood flow. DESIGN: Prospective, controlled animal study. SETTING: The surgical research unit of a university hospital. SUBJECTS: A total of 13 anesthetized and mechanically ventilated pigs. INTERVENTIONS: Pigs were subjected to stepwise mesenteric blood flow reduction (15% in each step, n = 8) or served as controls (n = 5). Superior mesenteric arterial blood flow was measured with ultrasonic transit time flowmetry, and mucosal and muscularis microcirculatory perfusion in the small bowel were each measured with three laser Doppler flow probes. Small-bowel intramucosal Pco2 was measured by tonometry, and glucose, lactate (L), and pyruvate (P) were measured by microdialysis. MEASUREMENTS AND MAIN RESULTS: In control animals, superior mesenteric arterial blood flow, mucosal microcirculatory blood flow, intramucosal Pco2, and the lactate/pyruvate ratio remained unchanged. In both groups, mucosal blood flow was better preserved than muscularis blood flow. During stepwise mesenteric blood flow reduction, heterogeneous microcirculatory blood flow remained a prominent feature (coefficient of variation, approximately 45%). A 30% flow reduction from baseline was associated with a decrease in microdialysis glucose concentration from 2.37 (2.10-2.70) mmol/L to 0.57 (0.22-1.60) mmol/L (p < .05). After 75% flow reduction, the microdialysis lactate/pyruvate ratio increased from 8.6 (8.0-14.1) to 27.6 (15.5-37.4, p < .05), and arterial-intramucosal Pco2 gradients increased from 1.3 (0.4-3.5) kPa to 10.8 (8.0-16.0) kPa (p < .05). CONCLUSIONS: Blood flow redistribution and heterogeneous microcirculatory perfusion can explain apparently maintained regional oxidative metabolism during mesenteric hypoperfusion, despite local signs of anaerobic metabolism. Early decreasing glucose concentrations suggest that substrate supply may become crucial before oxygen consumption decreases.

Antiproliferative effects of mistletoe (Viscum album L.) extract in urinary bladder carcinoma cell lines

BACKGROUND: The aim of the study was to evaluate the antiproliferative potency of Viscum album extract (VA-E) in human bladder carcinoma cell lines with regard to its possible use for intravesical therapy of superficial bladder cancer. MATERIALS AND METHODS: Proliferation (MTT-test or 3H-thymidine incorporation), necrotic disintegration (3H-thymidine release of prelabelled cells) and portions of apoptotic and/or necrotic cells (Annexin-V binding, propidium iodide (PI) labelling and DNA-fluorescence profiles by flow cytometry) were measured in four different human bladder carcinoma cell lines (T24, TCCSUP, J82 and UM-UC3) cultured in vitro. RESULTS: Antiproliferative effects of VA-E were observed in the four bladder carcinoma cell lines tested. Metabolic activity could also be completely abrogated by short-time contact of the cells with VA-E. Apoptosis and necrosis, as underlying mechanisms of action, were differentially expressed by the different cell lines. CONCLUSION: VA-E and cytotoxic proteins, i.e., mistletoe lectins (ML) and viscotoxins (VT), were able to block the growth of bladder carcinoma cells. Together with the immunomodulating properties of VA-E, the observed antiproliferative potency might give a rationale for the topical intravesical application of VA-E for the treatment of superficial bladder cancer.