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INTRODUCTION: Congenital hydrocephalus often results in irreversible and severe damage to the brain despite postnatal interventions. The potential for prenatal intervention to mitigate these deleterious effects underscores the importance of a suitable animal model. We aimed assess the results of an ultrasound guided transuterine approach to replicate the BioGlue injection fetal hydrocephalus model. METHODS: Pregnant ewes were anesthetized at 95 days of gestation and BioGlue was injected into the fetal cisterna magna under ultrasound guidance through the uterus. Ventriculomegaly was assessed by MRI and histology. RESULTS: Nine pregnant ewes were included in the study, and their fetuses were divided into the the BioGlue intervention group (n=9 fetuses) or the control group (n=7 fetuses) who were not injected. Although hydrocephalus was noted in 5 of 9 fetuses in the intervention group, the ability to induce hydrocephalus went from 0% to 100% in the last 3 fetuses following technical modifications. None of the controls developed hydrocephalus. Fetal brains with hydrocephalus demonstrated increased IBA1+ compared to control animals. CONCLUSIONS: While technical challenges were noted, the ultrasound guided transuterine approach to replicate the BioGlue fetal hydrocephalus model in sheep showed consistent and reproducible results. This model offers the advantage of directly visualizing the location of the needle tip and injection of the BioGlue. This technique offers an alternative for testing novel approaches for prenatal congenital hydrocephalus treatment.
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Eosinophil granule proteins are deposited in cutaneous lesions in many human diseases, but how these proteins contribute to pathophysiology is obscure. We injected eosinophil cationic protein (ECP or RNase 3), eosinophil-derived neurotoxin (EDN or RNase 2), eosinophil peroxidase (EPO), and major basic protein-1 (MBP1) intradermally into guinea pig and rabbit skin. ECP and EDN each induced distinct skin lesions at >or=2.5 microM that began at 2 days, peaking at approximately 7 days and persisting up to 6 wk. These lesions were ulcerated (ECP) or crusted (EDN) with marked cellular infiltration. EPO and MBP1 (10 microM) each produced perceptible induration and erythema with moderate cellular infiltration resolving within 2 wk. ECP and EDN localized to dermal cells within 2 days, whereas EPO and MBP1 remained extracellular. Overall, cellular localization and RNase activity of ECP and EDN were critical for lesion formation; differential glycosylation, net cationic charge, or RNase activity alone did not account for lesion formation. Ulcerated lesions from patients with the hypereosinophilic syndrome showed ECP and EDN deposition comparable to that in guinea pig skin. In conclusion, ECP and EDN disrupt skin integrity and cause inflammation. Their presence in ulcerative skin lesions may explain certain findings in human eosinophil-associated diseases.
Assuntos
Proteínas Granulares de Eosinófilos/toxicidade , Eosinófilos/enzimologia , Ribonucleases/toxicidade , Dermatopatias/etiologia , Animais , Proteína Catiônica de Eosinófilo/administração & dosagem , Proteína Catiônica de Eosinófilo/toxicidade , Proteínas Granulares de Eosinófilos/administração & dosagem , Proteína Básica Maior de Eosinófilos/administração & dosagem , Proteína Básica Maior de Eosinófilos/toxicidade , Peroxidase de Eosinófilo/administração & dosagem , Peroxidase de Eosinófilo/toxicidade , Neurotoxina Derivada de Eosinófilo/administração & dosagem , Neurotoxina Derivada de Eosinófilo/toxicidade , Eosinofilia/patologia , Cobaias , Humanos , Coelhos , Ribonucleases/administração & dosagem , Dermatopatias/patologia , Úlcera/etiologiaRESUMO
To investigate the role of HLA-DQ molecules and/or CD4(+) T cells in the pathogenesis of allergic asthma, we generated HLA-DQ6 and HLA-DQ8 transgenic mice lacking endogenous class II (Abeta(null)) and CD4 genes and challenged them intranasally with short ragweed allergenic extract (SRW). We found that DQ6/CD4(null) mice developed a strong eosinophilic infiltration into the bronchoalveolar lavage and lung tissue, while DQ8/CD4(null) mice were normal. However, neither cytokines nor eosinophil peroxidase in the bronchoalveolar lavage of DQ6/CD4(null) mice was found. In addition, the airway reactivity to methacholine was elevated moderately in DQ6/CD4(null) mice compared with the high response in DQ/CD4(+) counterparts and was only partially augmented by CD4(+) T cell transfer. The DQ6/CD4(null) mice showed Th1/Th2-type cytokines and SRW-specific Abs in the immune sera in contrast to a direct Th2 response observed in DQ6/CD4(+) mice. The proliferative response of spleen mononuclear cells and peribronchial lymph node cells demonstrated that the response to SRW in DQ6/CD4(null) mice was mediated by HLA-DQ-restricted CD4(-)CD8(-)NK1.1(-) T cells. FACS analysis of PBMC and spleen mononuclear cells demonstrated an expansion of double-negative (DN) CD4(-)CD8(-)TCRalphabeta(+) T cells in SRW-treated DQ6/CD4(null) mice. These cells produced IL-4, IL-5, IL-13, and IFN-gamma when stimulated with immobilized anti-CD3. IL-5 ELISPOT assay revealed that DN T cells were the cellular origin of IL-5 in allergen-challenged DQ6/CD4(null) mice. Our study shows a role for HLA-DQ-restricted CD4(+) and DN T cells in the allergic response.