Advanced Therapy Medicinal Products for Age-Related Macular Degeneration; Scaffold Fabrication and Delivery Methods.

Retinal degenerative diseases such as age-related macular degeneration (AMD) represent a leading cause of blindness, resulting in permanent damage to retinal cells that are essential for maintaining normal vision. Around 12% of people over the age of 65 have some form of retinal degenerative disease. Whilst antibody-based drugs have revolutionised treatment of neovascular AMD, they are only effective at an early stage and cannot prevent eventual progression or allow recovery of previously lost vision. Hence, there is a clear unmet need to find innovative treatment strategies to develop a long-term cure. The replacement of damaged retinal cells is thought to be the best therapeutic strategy for the treatment of patients with retinal degeneration. Advanced therapy medicinal products (ATMPs) are a group of innovative and complex biological products including cell therapy medicinal products, gene therapy medicinal products, and tissue engineered products. Development of ATMPs for the treatment of retinal degeneration diseases has become a fast-growing field of research because it offers the potential to replace damaged retinal cells for long-term treatment of AMD. While gene therapy has shown encouraging results, its effectiveness for treatment of retinal disease may be hampered by the body's response and problems associated with inflammation in the eye. In this mini-review, we focus on describing ATMP approaches including cell- and gene-based therapies for treatment of AMD along with their applications. We also aim to provide a brief overview of biological substitutes, also known as scaffolds, that can be used for delivery of cells to the target tissue and describe biomechanical properties required for optimal delivery. We describe different fabrication methods for preparing cell-scaffolds and explain how the use of artificial intelligence (AI) can aid with the process. We predict that combining AI with 3D bioprinting for 3D cell-scaffold fabrication could potentially revolutionise retinal tissue engineering and open up new opportunities for developing innovative platforms to deliver therapeutic agents to the target tissues.

Bioengineering of Antibody Fragments: Challenges and Opportunities.

Antibody fragments are used in the clinic as important therapeutic proteins for treatment of indications where better tissue penetration and less immunogenic molecules are needed. Several expression platforms have been employed for the production of these recombinant proteins, from which E. coli and CHO cell-based systems have emerged as the most promising hosts for higher expression. Because antibody fragments such as Fabs and scFvs are smaller than traditional antibody structures and do not require specific patterns of glycosylation decoration for therapeutic efficacy, it is possible to express them in systems with reduced post-translational modification capacity and high expression yield, for example, in plant and insect cell-based systems. In this review, we describe different bioengineering technologies along with their opportunities and difficulties to manufacture antibody fragments with consideration of stability, efficacy and safety for humans. There is still potential for a new production technology with a view of being simple, fast and cost-effective while maintaining the stability and efficacy of biotherapeutic fragments.

High Incidence of Virulence Factors Among Clinical Enterococcus faecalis Isolates in Southwestern Iran / 감염과화학요법

BACKGROUND: Over the past two decades, enterococci have emerged as an important agent responsible for hospital acquired infection. Several virulence factors contribute to the adherence, colonization, evasion of the host immune response, and pathogenicity and severity of the infection. Enterococcus faecalis is the most common and virulent species causing infections in hospitalized patients. The aim of the present study was to examine the prevalence of genes encoding virulence factors and antimicrobial resistance patterns of E. faecalis strains isolated from hospitalized patients in Shiraz, south west of Iran. MATERIALS AND METHODS: A total of 51 E. faecalis isolates from the urine, blood, pleural fluid, peritoneal fluid, eye discharge, endotracheal tube (ETT) and transjugular intrahepatic portosystemic shunt (TIPS) specimens of patients were identified by phenotypic and genotypic methods. Antimicrobial sensitivity tests and detection of virulence factors were performed using standard methods. RESULTS: The efa and asa1 were the most frequently detected gene (100%) among the isolates, followed by esp (94.1%), ace (90.2%), gelE (80.4%), cylA (64.7%), and hyl (51%). More than half of the isolates (52.9%) were high level gentamicin resistant (HLGR). Vancomycin resistance was observed among 23 (45.1%) isolates. The lowest antimicrobial activity was related to erythromycin (3.9%), tetracycline (5.9%) and ciprofloxacin (9.8%). No isolate was found resistant to fosfomycin and linezolid. CONCLUSION: Our data indicated a high incidence of virulence factors among E. faecalis strains isolated from clinical samples. Colonization of drug resistant virulent isolates in hospital environment may lead to life threatening infection in hospitalized patients. Therefore, infection control procedures should be performed.

Effects of Hydro-alcoholic Extract from Arctium lappa L. (Burdock) Root on Gonadotropins, Testosterone, and Sperm Count and Viability in Male Mice with Nicotinamide/ Streptozotocin-Induced Type 2 Diabetes

Background: Reproductive dysfunction is a complication of diabetes. Arctium lappa (burdock) root has hypoglycemic and antioxidative properties, which are traditionally used for treatment of impotence and sterility. Therefore, the aim of this study is to investigate the effects of its hydro alcoholic extract on gonadotropin, testosterone, and sperm parameters in nicotinamide/ streptozotocin-induced diabetic mice. Methods: In this experimental study, 56 adult male Naval Medical Research Institute (NMRI) mice (30–35 g) were randomly divided into seven groups: control, diabetes, diabetes + glibenclamide (0.25 mg/kg), diabetes + extract (200 or 300 mg/kg), and extract (200 or 300 mg/kg). Diabetes was induced with intraperitoneal injection of nicotinamide (NA) and streptozotocin (STZ). Twenty-four hours after the last extract and drug administration, serum samples, testes, and cauda epididymis were removed immediately for experimental assessment. Results: Body weight, serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone levels, and sperm count (P < 0.05) and viability (P < 0.01) decreased in diabetic mice. Administration of glibenclamide significantly improved these reductions in diabetic animals (P < 0.05). However, the hydro alcoholic extract (300 mg/kg) enhanced sperm viability only in diabetic mice (P < 0.01). In addition, this dose of extract increased sperm count, LH, FSH, and testosterone in nondiabetic animals compared with the control group (P < 0.05). Conclusion: The results indicate that applied burdock root extract has anti-infertility effects in nondiabetic mice. Hence, this part of the A. lappa plant has an effect on the health of the reproductive system in order to improve diabetic conditions.

Effects of Hydro-Alcoholic Extract of Rhus coriaria (Sumac) Seeds on Reproductive Complications of Nicotinamide-Streptozotocin Induced Type-2 Diabetes in Male Mice

PURPOSE: The purpose of this study was to investigate the effects of the hydro-alcoholic extract of Rhus coriaria seeds on the reproductive system of nicotinamide-streptozotocin-induced type-2 diabetic mice. MATERIALS AND METHODS: In this experimental study, 56 male Naval Medical Research Institute mice were randomly divided into seven groups (n=8): control; diabetic mice; diabetic mice administered glibenclamide (0.25 mg/kg); diabetic mice who received the hydro-alcoholic extract of R. coriaria seeds (200 and 400 mg/kg groups); and normal mice who received this extract (200 and 400 mg/kg groups). Diabetes was induced by intraperitoneal administration of streptozotocin (65 mg/kg) 15 minutes after an injection of nicotinamide (120 mg/kg). Then, glibenclamide and the above mentioned extract were administered orally for 28 consecutive days. Twenty-four hours after the last treatment, serum samples, the testes, and the cauda epididymis were removed immediately for hormonal, testis morphology, and sperm parameter assessments. RESULTS: Body and testicular weight, sperm count and viability, and serum luteinizing hormone, follicle-stimulating hormone and testosterone levels were significantly lower in the diabetic mice (p<0.05). The diabetic mice treated with 400 mg/kg of the hydro-alcoholic extract of R. coriaria seeds recovered from these reductions (p<0.05). Further, glibenclamide alleviated hormonal and sperm count depletion in diabetes-induced mice (p<0.05). CONCLUSIONS: The present results indicated that the hydro-alcoholic extract of R. coriaria seeds has anti-infertility effects in diabetic males.

Effects of Exendin-4 on Male Reproductive Parameters of D-Galactose Induced Aging Mouse Model

PURPOSE: The purpose of this study was to evaluate the role of exendin-4 on reproductive alteration in a D-galactose-induced aging mouse model. MATERIALS AND METHODS: In this experimental study, 72 male Naval Medical Research Institute mice (20~25 g) were randomly divided into six groups: control, exendin-4 (1 nmol/kg), exendin-4 (10 nmol/kg), D-galactose (500 mg/kg), D-galactose+exendin-4 (1 nmol/kg), and D-galactose+exendin-4 (10 nmol/kg). The aging model animals were gavaged with D-galactose for six weeks, and exendin-4 was injected intraperitoneally in the last 10 days. At the end of treatment serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone levels were evaluated and the cauda epididymis and testis were removed to analyze the sperm count and testis morphology. RESULTS: The testis weight and volume decreased in the D-galactose group (p<0.01 and p<0.05) respectively. Exendin-4 (1, 10 nmol/kg) increased these parameters in the normal and aging mouse models. Serum LH and FSH levels increased and the sperm count decreased in the D-galactose group (p<0.05). Further, exendin-4 (1 nmol/kg) decreased LH and FSH levels and increased the serum testosterone level and sperm count in both normal and aging animals. CONCLUSIONS: D-galactose can induce aging alternations in the male reproductive system such as decreased sperm count and increased serum LH and FSH levels through reactive oxygen species over production and reduced antioxidant enzyme activity. Further, co-administration of exendin-4 reduced reproductive complications of D-galactose in an aging mouse model.