Advancing the understanding of the mechanisms involved in the pathogenesis of multiple sclerosis (MS) likely will lead to new and better therapeutics. Although important information about the disease process has been obtained from research on pathologic specimens, peripheral blood lymphocytes and MRI studies, the elucidation of detailed mechanisms has progressed largely through investigations using animal models of MS. In addition, animal models serve as an important tool for the testing of putative interventions. The most commonly studied model of MS is experimental autoimmune encephalomyelitis (EAE). This model can be induced in a variety of species and by various means, but there has been concern that the model may not accurately reflect the disease process, and more importantly, it may give rise to erroneous findings when it is used to test possible therapeutics. Several reasons have been given to explain the shortcomings of this model as a useful testing platform, but one idea provides a framework for improving the value of this model, and thus, it deserves careful consideration. In particular, the idea asserts that EAE studies are inadequately designed to enable appropriate evaluation of putative therapeutics. Here we discuss problem areas within EAE study designs and provide suggestions for their improvement. This paper is principally directed at investigators new to the field of EAE, although experienced investigators may find useful suggestions herein.

Providing stimulation and allowing the performance of motivated behaviors through environmental enrichment improves learning and memory in rodents and delays cognitive impairment in neurodegenerative disease models. The leaner mutation affects the Ca_v2.1 voltage-gated calcium channel α_1A-subunit gene, and homozygous mice show severe phenotypic alterations. Although several authors have described heterozygous mice as normal, recent studies in our laboratory indicate motor and cognitive impairment in tg^la/+ mice. In the present study, we evaluated whether this impairment is robust to systematic variation of the housing environment from barren to standard and furnished (enriched) cages. Wildtype (n = 55) and tg^la/+ (n = 79) C57Bl/6J mice were assigned randomly to 1 of the 3 housing systems and tested on the Morris water maze at 6, 12, and 20 mo of age. The results confirmed impaired performance in tg^la/+ mice, particularly in older mice. At 12 and 20 mo, only wildtype (and not tg^la/+) mice showed evidence of learning (spending increased time in the target quadrant) during the probe trial. Housing also affected performance: at 12 mo, only mice from furnished cages showed evidence of learning, and in aged mice (20 mo), only those housed in more complex environments showed long-term memory (8 mo after previous testing) of the platform position. In conclusion, a heterozygous mutation in a Ca²⁺ channel gene causes cognitive deficits in leaner mice that are robust to environmental variation but attenuated by physical and behavioral stimulation.

Mucopolysaccharidosis type IIIB (MPS IIIB; Sanfilippo syndrome type B) is a metabolic disorder with devastating clinical characteristics starting in early childhood and leading to premature death. A knockout mouse strain was developed that models this disease. Mice of the strain B6.129S6- Naglu^tm1Efn/J are invaluable for investigating pathogenesis and possible treatment modalities. However, the mouse strain also exhibits some objectionable phenotypic features. One such feature, urinary retention, not only is atypical of human MPS IIIB but often leads to early termination of experiments due to animal welfare concerns. The aim of this study was to investigate abnormalities associated with the urinary retention. Necropsies were performed on 9-mo-old mice; urinalysis, hematology and blood chemistry parameters were evaluated, and urogenital specimens were microscopically examined. Histopathologic examinations of urinary tract specimens proved illuminating regarding pathology in the urinary tract. A large mononuclear cell infiltrate was discovered in mutant mice of both sexes, more pronounced in females compared with male mice. The infiltrate comprises of large rounded or polygonal cells with generous variably vacuolated, granular eosinophilic cytoplasm and small round vesicular nuclei. These cells were present throughout and expand the interstitium of the lower urinary tract. Either this results in extrinsic compression of the lumen of the urethra, eventually leading to obstructive uropathy, bladder hyperdistension, and urinary retention or possibly interferes with the neurogenic component of micturition needs to be further investigated. The novel finding of an unexpected mononuclear cell infiltrate in the urinary tract in the knockout mice B6.129S6- Naglu^tm1Efn/J is reported.

Inositol hexaphosphate (IP₆) is a naturally occurring polyphosphorylated carbohydrate that is abundant in many plants and in various high-fiber foods, such as cereals and legumes. IP₆ has a striking, broad-spectrum anticancer activity in various in vitro and animal models, in which it interferes with key pathways in malignancy to inhibit cell proliferation, cell-cycle progression, metastasis, invasion, and angiogenesis and to induce apoptosis. In this study, we investigated the protective effects of IP₆ in drinking water on the incidence of UVB-induced skin cancer in the SKH1 (Crl: SKH1-hr) mouse model. One group of 15 mice received 2% IP₆ in drinking water and UVB exposure, and the other group (n = 15) received UVB exposure only. All mice in both groups were fed an IP₆-deficient diet (AIN 76A). The treatment group started receiving 2% IP₆ in the drinking water 3 d before irradiation. Mice were irradiated 3 times each week, starting at a dose of 1.5 kJ/m², with weekly increases in increments of 1.5 kJ/m² to a final dose of 7.5 kJ/m². Tumor formation was monitored until the week 31. IP₆ in drinking water significantly decreased tumor incidence by 5-fold and tumor multiplicity by 4-fold. These results show that IP₆ has an antiphotocarcinogenic effect and can protect against UVB-induced tumor formation.

Data implicating mucosal cytokines in the pathogenesis of canine inflammatory bowel disease (IBD) are limited. The aims of the present study were to report new findings of intestinal cytokine expression in dogs with IBD and to compare these data with previous studies through meta-analysis. Cytokine mRNA abundance in intestinal biopsies collected prospectively was evaluated by using a semiquantitative RT-PCR technique. For meta-analysis, an electronic database search revealed 3 clinical trials, all of which were nonrandomized (type III) case series. Prospective analysis showed that the intestines of healthy dogs and those with IBD express numerous cytokines and that a proinflammatory expression profile is not a feature of small or large-intestinal IBD. The meta-analysis data included 158 dogs characterized as healthy (n = 45), diarrheic nonIBD dogs (n = 6), nonresponders (n = 2), small-intestinal IBD (n = 41), colonic IBD (n = 25), and chronic enteropathy (n = 39). German shepherd dogs were overrepresented in 3 of the 4 studies. Healthy dogs showed mRNA expression for most cytokines including IL2, IL4, IL5, IL10, IL12, IFNγ, TNFα, and TGFβ. Only IL12 mRNA expression was increased consistently in small-intestinal IBD, whereas IBD colitis lacked consistent patterns of expression. In summary, dogs with IBD fail to express a predominant Th1- or Th2 cytokine bias in inflamed mucosa. Heterogeneity of results among these studies might be explained by numerous factors including the method of mRNA quantification, stage of disease, and demographic differences in study populations.

A bovine colostral antibody against verotoxin (VT) 2 of Escherichia coli O157:H7 was administered orally to beagle dogs. The antibody remained in the dogs' small intestine for at least 2 h, whereas little serum antibody remained 1.5 h after administration. Furthermore, the antibody activity of secretory IgA did not change until 2 h after administration; however, the activity of IgG and IgM antibodies decreased by approximately 60% and 40% at 2 h after administration, respectively. Seven beagle dogs inoculated with Escherichia coli O157:H7 producing VT2 were administered bovine colostral antibody or bovine colostral whey without antibody. With administration of bovine colostral whey without antibody, the amount of VT2 in feces decreased gradually after administration and increased again at 5 d after inoculation, whereas bovine colostral antibody significantly reduced the amount of VT2 in feces on the day after administration. In addition, 9 beagle dogs were given bovine colostral antibody, bovine plasma antibody, or saline. The amount of VT2 in feces again decreased significantly more rapidly after administration of bovine colostral antibody than after administration of bovine plasma antibody or saline.

Secondary hepatic amyloidosis in nonhuman primates carries a grave prognosis once animals become clinically ill. The purpose of this study was to establish serologic parameters that potentially could be used to identify rhesus macaques undergoing subclinical development of secondary hepatic amyloidosis. A retrospective analysis was completed by using serum biochemical profiles from 26 histologically diagnosed amyloidotic macaques evaluated at 2 stages of disease, clinical and subclinical (3 to 32 mo prior to clinical signs of disease). Standard serum biochemistry values for cases were compared with institutional age- and gender-specific references ranges by construction of 95% confidence intervals for the difference between means. In addition, 19 histologically diagnosed amyloidotic macaques and 19 age-matched controls were assayed for changes in various parameters by using routinely banked, frozen (–80 °C) sera available from clinical and subclinical time points. Clinically amyloidotic animals displayed increased levels of alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase, gamma glutamyltranspeptidase, and macrophage colony-stimulating factor and significantly decreased quantities of albumin and total cholesterol. Subclinical amyloidotic animals displayed increased levels of alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase, and serum amyloid A and decreased concentrations of albumin and total cholesterol. The serologic parameters studied indicate a temporal relationship of these factors not previously described, show a clear pattern of disease progression, and could be useful in subclinical disease detection.

Giardia intestinalis is a common protozoan parasite that can infect many laboratory animal primates, although its role as a contributor to the induction of gastrointestinal disease remains unclear. This study sought to investigate the prevalence of Giardia in a colony of common marmosets by using a Giardia antigen-capture assay and to address the possible eradication of this infection by using tinidazole, an antiprotozoal similar to metronidazole but requiring fewer doses. Among 31 colony marmosets, 13 (42%) were positive for Giardia. Two doses of oral tinidazole eliminated the infection in all animals. Repeat testing of the 13 Giardia-positive monkeys 1 y later showed that 11 remained negative and that treated animals had a significant increase in weight at 1 y. Giardia antigen is common in common marmoset feces, and treatment using oral tinidazole is possible and highly effective.

An outbreak of mousepox in a research institution was caused by Ectromelia-contaminated mouse serum that had been used for bone marrow cell culture and the cells subsequently injected into the footpads of mice. The disease initially was diagnosed by identification of gross and microscopic lesions typical for Ectromelia infection, including foci of necrosis in the liver and spleen and eosinophilic intracytoplasmic inclusion bodies in the skin. The source of infection was determined by PCR analysis to be serum obtained from a commercial vendor. To determine whether viral growth in tissue culture was required to induce viral infection, 36 mice (BALB/cJ, C57BL/6J) were experimentally exposed intraperitoneally, intradermally (footpad), or intranasally to contaminated serum or bone marrow cell cultures using the contaminated serum in the culture medium. Mice were euthanized when clinical signs developed or after 12 wk. Necropsy, PCR of spleen, and serum ELISA were performed on all mice. Mice injected with cell cultures and their cage contacts developed mousepox, antibodies to Ectromelia, and lesions, whereas mice injected with serum without cells did not. Mouse antibody production, a tool commonly used to screen biologic materials for viral contamination, failed to detect active Ectromelia contamination in mouse serum.

We report here the characterization of an asymmetric ataxia syndrome (head tilt and circling, with death in the most severe cases) demonstrated by profoundly immunodeficient mice housed at the Institut Curie SPF facility. The immune system of the affected mice had been genetically modified so that they were deficient in both B and T cells. Extensive bacteriologic, parasitic, serologic, and histopathologic analysis of the affected animals and their healthy controls led us to identify Ralstonia pickettii as the causative agent of the ataxic syndrome. The outbreak was managed through a test-and-cull process. Even though they also carried Ralstonia pickettii, immunocompetent mice that were kept in the same facility, did not show any of the signs that were expressed by their immunodeficient counterparts. This case highlights the difficulty of maintaining immunocompetent and immunodeficient mice in the same microbiologic unit and the importance of enlarging the spectrum of health monitoring to opportunistic agents when investigating clinical cases in populations of immunocompromised rodents.