Glial Fibrillary Acidic Protein and Ionized Calcium-Binding Adapter Molecule 1 Immunostaining Score for the Central Nervous System of Horses With Non-suppurative Encephalitis and Encephalopathies

Abstract

Like humans, horses are susceptible to neurotropic and neuroinvasive pathogens that are not always readily identified in histological sections. Instead, alterations in astrocytes and microglia cells can be used as pathological hallmarks of injured nervous tissue in a variety of infectious and degenerative diseases. On the other hand, equine glial cell alterations are poorly characterized in diseases. Therefore, in this study, we provide a statistically proved score system to classify astrogliosis and microgliosis in the central nervous system (CNS) of horses, based on morphological and quantitative analyses of 35 equine cases of encephalitis and/or encephalopathies and four non-altered CNS as controls. For this system, we used glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (Iba1) immunohistochemistry, allied to statistical analysis to confirm that the scores were correctly designated. The scores of alterations ranged from 0 (non-altered) to 3 (severely altered) and provided a helpful method for describing astrocytic and microglial alterations in horses suffering from inflammatory and degenerative lesions. This system could be a template for comparative studies in other animal species and could aid algorithms designed for artificial intelligence methods lacking a defined morphological pattern.

Metallothionein I/II Expression and Metal Ion Levels in Correlation with Amyloid Beta Deposits in the Aged Feline Brain

“…Age-dependent astrogliosis has been reported in animals including dogs [23,70], cattle [71], horses [72], and cats [6,28]. Accordingly, in the present study, the identification of GFAPpositive astrocytes and further classification into four separate grades were performed based on Boos et al (2021), and a statistically significant age-related increase in size and number of positive astrocytes was observed [35]. Given that astrocytes outnumber neurons in the brain and reactive astrogliosis is associated with aging, these could lead to astrocyte contribution in Aβ production in aged humans and/or animals [30,68].…”

“…Tissue sections examined immunohistochemically for GFAP were evaluated by performing both morphological and quantitative analysis. Astrocytic GFAP grading based on morphological and quantitative criteria was classified according to Boos et al (2021), as described in Table 3 [35]. The number of GFAP-positive astrocytes was assessed by calculating the mean number of astrocytes counted in five random fields (20× original magnification).…”

Adeno-Associated Virus-Mediated Dorsal Root Ganglion Toxicity in the New Zealand White Rabbit

“…In addition to the routine H&E stain, IHC staining against GFAP and GLUL, 13 both known markers for satellite glial cells, were performed on all DRG for all animals in Study 2 only to better distinguish satellite glial cells from mononuclear cell infiltrates. GLUL IHC signal intensity in the immunopositive satellite glial cells appeared more consistent across all groups including controls when compared with the GFAP IHC signal intensity; therefore, only GLUL IHC was used to assess AAV-related increased cellularity of these cells (Table 3).…”

“…The care and use of the animals on the study were conducted in accordance with the guidelines of the US National Research Council and the Canadian Council on Animal Care. 7 All rabbits were housed in set-ups as described, 13 provided with toys and food enrichment, and fed 120 g per day of a certified laboratory rabbit diet and provided water ad libitum. At the time of necropsy, all animals were administered a sedative, Ketamine HCl for injection, xylazine and glycopyrrolate by intramuscular injection and euthanized by exsanguination via incision of the axillary or femoral arteries.…”

The protective effect of taurine, piracetam and vinpocetine on etoposideinduced inflammation and brain injury in the serum of female albino rats

“…All slides were coded with random numbers for the blind investigation conducted by a skillful pathologist. The morphological alterations in astrocytes were graded semi-quantitively according to Boos et al [50] scoring system illustrated in Table 1. Quantitative analysis of GFAP immunostaining intensity was also determined by measuring the area percent of GFAP-expression of all photomicrographs of brain sections from each group using image analysis software (Image J, version 1.53k, NIH, Bethesda, MD, USA).…”