Assessment of glial fibrillary acidic protein and anti-glial fibrillary acidic protein autoantibody concentrations and necrotising meningoencephalitis risk genotype in dogs with pug dog myelopathy.

BACKGROUND: Pugs commonly present with thoracolumbar myelopathy, also known as pug dog myelopathy (PDM), which is clinically characterised by progressive signs involving the pelvic limbs, no apparent signs of pain and, often, incontinence. In addition to meningeal fibrosis and focal spinal cord destruction, histopathology has confirmed lymphohistiocytic infiltrates in the central nervous system (CNS) in a considerable number of pugs with PDM. Lymphohistiocytic CNS inflammation also characterises necrotising meningoencephalitis (NME) in pugs. This study aimed to investigate the potential contribution of an immunological aetiology to the development of PDM. METHODS: The concentrations of glial fibrillary acidic protein (GFAP) in serum and CSF and of anti-GFAP autoantibodies in CSF were measured with an ELISA. In addition, a commercial test was used for genetic characterisation of the dog leukocyte antigen class II haplotype, which is associated with NME susceptibility. RESULTS: This study included 87 dogs: 52 PDM pugs, 14 control pugs, four NME pugs and 17 dogs of breeds other than pugs that were investigated for neurological disease (neuro controls). Anti-GFAP autoantibodies were present in 15 of 19 (79%) of the PDM pugs tested versus six of 16 (38%) of the neuro controls tested (p = 0.018). All 18 PDM pugs evaluated had detectable CSF GFAP. Serum GFAP was detected in two of three (67%) of the NME pugs and in two of 11 (18%) of the control pugs but not in any of the 40 tested PDM pugs. Male pugs heterozygous for the NME risk haplotype had an earlier onset of clinical signs (70 months) compared to male pugs without the risk haplotype (78 months) (p = 0.036). LIMITATIONS: The study was limited by the lack of healthy dogs of breeds other than pugs and the small numbers of control pugs and pugs with NME. CONCLUSIONS: The high proportion of PDM pugs with anti-GFAP autoantibodies and high CSF GFAP concentrations provide support for a potential immunological contribution to the development of PDM.

Gene Expression Analysis of the Irrigation Solution Samples Collected during Vitrectomy for Idiopathic Epiretinal Membrane.

PURPOSE: The analysis of gene expression in idiopathic epiretinal membranes (iERMs) may help elucidate ERM formation and its pathology. Here, we conducted a case-control study, in order to determine the expression levels of cytokines and other genes in eyes with macular hole (MH) or iERM. METHODS: Twenty eyes, obtained from seven male and 13 female patients, were included in the study. The average age of the study subjects was 69.1 ± 7.67 years, and 15 eyes had iERM, while five eyes had MH. Irrigation solution samples were collected during vitrectomy, centrifuged, and the levels of cytokine and other mRNAs in the sediment were assessed using real-time PCR. The expression level of 11 cytokine genes, four transcription factor genes, two cytoskeletal genes, and genes encoding two extracellular matrix proteins in eyes with MH or iERM were determined and compared. RESULTS: The expression levels of interleukin 6 (IL6), tumor growth factor B2 (TGFB2), vascular endothelial growth factor A (VEGFA), chemokine C-X-C motif ligand 1 (CXCL1), v-rel avian reticuloendotheliosis viral oncogene homolog A (RELA), glial fibrillary acidic protein (GFAP), and tenascin C (TNC) were significantly higher in eyes with iERM than in eyes with MH. The expression of these genes was not associated with the preoperative visual acuity of the investigated patients. CONCLUSIONS: The obtained results indicate that real-time PCR analysis of irrigation solution samples collected during vitrectomy can help assess the expression levels of several genes, and that iERM is associated with the expression of pro-inflammatory genes and the genes expressed during angiogenesis and wound healing process (IL6, TGFB2, VEGFA, CXCL1, RELA, GFAP, and TNC).

1H-MRS assessment of the therapeutic effect of bilateral intraventricular BDNF infusion into APP/PS1 double transgenic mice.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by extracellular accumulation of amyloid deposits. Brain-derived neurotrophic factor (BDNF) is a neurotrophic factor whose levels have been shown to be decreased in AD brains. BDNF supplementation can offer improvement in the course of AD. However, the means of assessment are still relatively limited. In the present study, 1H-MRS was used to evaluate the therapeutic effects of bilateral intraventricular BDNF infusion into Alzheimer's disease APP/PS1 double transgenic mice. For comparison to the 1H-MRS observations, Fluoro-Jade B staining and immunofluorescence for beta amyloid peptides (Aß), glial fibrillary acidic protein, and tropomyosin-related kinase B (TrkB) were also performed. Our results showed that N-acetylaspartate (NAA) levels increased and myoinositol levels decreased in the BDNF group compared with the PBS group. However, the BDNF group NAA level was still lower than the control group at 6 weeks after infusion. These changes correlated with increased immunoreactivity for TrkB, decreased compact Aß peptide containing plaques, and decreased Fluoro-Jade B-positive cells in the BDNF-infused mice compared to vehicle controls. These findings demonstrate that 1H-MRS may be a promising means of evaluating the therapeutic effects of BDNF on AD.

Morphological assessment of the development of multinucleated giant cells in glioma by using mitosis-specific phosphorylated antibodies.

OBJECT: The nature and origin of multinucleated giant cells in glioma have not been made clear. To investigate the phosphorylation of intermediate filaments, the authors studied multinucleated giant cells in vitro and in vivo by using mitosis-specific phosphorylated antibodies. METHODS: Cultured human glioma cells were immunostained with monoclonal antibodies (mAbs) 4A4, KT13, and TM71, which recognized the phosphorylation of vimentin at Ser55, glial fibrillary acidic protein at Serl3, and vimentin at Ser71, respectively. Subsequently, the nature of multinucleated giant cells was investigated using laser scanning confocal microscopy. In addition, paraffin-embedded tissue sections obtained in three patients with giant cell glioblastoma were also investigated. Multinucleated giant cells were immunoreacted with the mAb 4A4 and not with KT13 and TM71 in vitro and in vivo. In addition, the authors obtained these results in multinucleated giant cells under natural conditions, without drug treatments. CONCLUSIONS: Findings in this investigation indicated that multinucleated giant cells are those remaining in mitosis between metaphase and telophase, undergoing neither fusion nor degeneration.

Neuronal activity regulates correlated network properties of spontaneous calcium transients in astrocytes in situ.

Spontaneous neuronal activity is essential to neural development. Until recently, neurons were believed to be the only excitable cells to display spontaneous activity. However, cultured astrocytes and, more recently, astrocytes in situ are now known to exhibit spontaneous Ca2+ transients. Here we used Ca2+ imaging of astrocytes from transgenic mice for the simultaneous monitoring of [Ca2+]i changes in large numbers of astrocytes. We found that spontaneous activity is a common property of most brain astrocytes that is lost in response to a lesion. These spontaneous [Ca2+]i oscillations require extracellular and intracellular Ca2+. Moreover, network analysis revealed that most astrocytes formed correlated networks of dozens of these cells, which were synchronous with both astrocytes and neurons. We found that decreasing spontaneous [Ca2+]i transients in neurons by TTX does not alter the number of active astrocytes, although it impairs their synchronous network activity. Conversely, bicuculline-induced epileptic patterns of [Ca2+]i transients in neurons cause an increase in the number of active astrocytes and in their network synchrony. Furthermore, activation of non-NMDA and NMDA ionotropic glutamate receptors is required to correlate astrocytic networks. These results show that spontaneous activity in astrocytes and neurons is patterned into correlated neuronal/astrocytic networks in which neuronal activity regulates the network properties of astrocytes. This network activity may be essential for neural development and synaptic plasticity.