This study explored systemic immune changes in 11 subjects with X-linked retinoschisis (XLRS) in a Phase I/IIa AAV8-RS1 gene therapy trial (www.ClinicalTrials.gov NCT02317887). Immune cell proportions and serum analytes were compared to 12 healthy male controls. At pre-dosing baseline the mean CD4/CD8 ratio of XLRS subjects was elevated. CD11c+ myeloid dendritic cells (DCs) and serum EGF level were decreased, while CD123+ plasmacytoid DCs and serum IFN-γ and TNF-α were increased, indicating that XLRS baseline immune status differs from controls. XLRS samples 14 days after AAV8-RS1 administration were compared with XLRS baseline. Frequency of CD11b+CD11c+ DC was decreased in 8 of 11 XLRS subjects across all vector doses (1e9 - 3e11 vg/eye). CD8+HLADR+ cytotoxic T cells and CD68+CD80+ macrophages were upregulated in 10 of 11 XLRS, along with increased serum granzyme-B in 8 of 11 XLRS and elevated IFN-γ in 9 of 11 XLRS. The six XLRS subjects with ocular inflammation after vector application gave modestly positive correlation of inflammation score to their respective baseline CD4/CD8 ratios. This exploratory study indicates that XLRS subjects may exhibit a proinflammatory, baseline immune phenotype, and that intravitreal dosing with AAV8-RS1 leads to systemic immune activation with an increase of activated lymphocytes, macrophages and proinflammatory cytokines.
Retinitis pigmentosa (RP) is a common retinal degeneration disease caused by mutation in any gene of the photo transduction cascade and results in photoreceptor dystrophy. Over decades, several animal models have been used to address the need for elucidation of effective therapeutics and factors regulating retinal degeneration to prohibit or renew the damaged retina. However, controversies over immune privilege of retina during cell transplantation and role of immune modulation during RP still remain largely uninvestigated due to lack of proper animal models. Therefore, in our present study, we have developed an immune compromised mouse model NOD.SCID- rd1 for retinitis pigmentosa (RP) by crossing CBA/J and NOD SCID mice and selecting homozygous double mutant animals for further breeding. Characterization of the newly developed RP model indicates similar retinal degeneration pattern as CBA/J with decreased apoptosis rate and rhodopsin loss. It also exhibits loss of T cells, B cells and NK cells. NOD.SCID- rd1model is extremely useful for xenogenic cell based therapeutics as indicated by higher cell integration capacity post transplantation. The dissection of underlying role of immune system in the progression of RP and effect of immune deficiency on immune privilege of eye has also been further elucidated using comparative qPCR studies of this model with immune competent RP model.
27 November 2019 in Journal of Visualized Experiments
Acute liver failure (ALF) is a clinical condition caused by various etiologies resulting in the loss of metabolic, biochemical, synthesizing, and detoxifying functions of the liver. In most irreversible liver damage cases, orthotropic liver transplant (OLT) remains the only available treatment. To study the therapeutic potential of a treatment for ALF, its prior testing in an animal model of ALF is essential. In the current study, an ALF model in rats was developed by combining 70% partial hepatectomy (PHx) and injections of acetaminophen (APAP) that provides a therapeutic window of 48 h. The median and left lateral lobes of the liver were removed to excise 70% of the liver mass and APAP was given 24 h postsurgically for 2 days. Survival in ALF-induced animals was found to be severely decreased. The development of ALF was confirmed by altered serum levels of the enzymes alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP); changes in prothrombin time (PT); and assessment of the international normalized ratio (INR). Study of the gene expression profile by qPCR revealed an increase in expression levels of genes involved in apoptosis, inflammation, and in the progression of liver injury. Diffused degeneration of hepatocytes and infiltration of immune cells was observed by histological evaluation. The reversibility of ALF was confirmed by the restoration of survival and serum levels of ALT, AST, and ALP after intrasplenic transplantation of syngeneic healthy rat hepatocytes. This model presents a reliable alternative to the available ALF animal models to study the pathophysiology of ALF as well as to evaluate the potential of a novel therapy for ALF. The use of two different approaches also makes it possible to study the combined effect of physical and drug-induced liver injury. The reproducibility and feasibility of current procedure is an added benefit of the model.
The cultivation of mycobacteria often requires the use of several antibiotics to limit the growth of other rapidly growing micro-flora present in the growth medium. This antibiotic cocktail is one of the most expensive reagents required for mycobacterium culture. Here we present a customized antibiotics mix that is easy to prepare at a fraction of the cost of the commercially available antibiotic mixture that protects against transient flora, which are normally present in lungs, without affecting mycobacterial colony number.