Factors Affecting the Availability and Utilization of Essential Medicines in India: A Systematic Review.

Essential medicines or drugs are recognized as highly cost-effective components within contemporary healthcare, demonstrating significant potential for improving health outcomes. The provision of essential medicines directly impacts the functioning of healthcare facilities, resulting in financial hardship. This review aims to fill knowledge gaps by examining obstacles hindering access and utilization of essential medicines in India. This study conducted a comprehensive evidence synthesis, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, to analyse articles on the availability and utilization of essential medicines in India. The search strategy included various databases and keywords. Published, peer-reviewed articles focusing on the National/ State List of Essential Medicines and meeting specific criteria were considered. Data items included essential medicines, drug availability, utilization, and challenges. Data was extracted, synthesized, and analysed using thematic framework analysis. Out of 1,129 articles, 11 were selected for review. Studies consistently highlighted the inadequate availability of essential medicines in different Indian states. Availability of essential medicines varies in the range of 17-51 percent across major states of India. Stock-outs of medicines vary from 4 to 14 weeks. Governance issues including differential procurement mechanisms across states of India, hinder seamless availability of essential medicines. Other challenges included distribution and purchasing system inefficiencies, governance-related issues, and facility/ user-level challenges impacting drug utilization. Disruptions in utilization were observed due to improper prescription practices and non-availability of affordable options. Accessibility and affordability also affected drug utilization. Issues with supply chain management and conflicting guidelines further contributed to the obstacles faced in ensuring availability and utilization of essential medicines in India. Ensuring the availability, accessibility, and affordability of essential medicines is of utmost importance. The public health system needs to strengthen its procurement and distribution management. Strengthening the logistics support for an efficient supply of essential medicines will reduce the time lag in receipt of drugs. Guidelines on essential drugs prepared by the National Health System Resource Centre need to be strictly adhered to and monitored in inventory management system. There is an urgent need to develop a sustainable model for achieving uniformity in the availability and utilization of essential medicines in India.

Commitment of human mesenchymal stromal cells towards ACL fibroblast differentiation upon rAAV-mediated FGF-2 and TGF-ß overexpression using pNaSS-grafted PCL films.

Despite various clinical options, human anterior cruciate ligament (ACL) lesions do not fully heal. Biomaterial-guided gene therapy using recombinant adeno-associated virus (rAAV) vectors may improve the intrinsic mechanisms of ACL repair. Here, we examined whether poly(sodium styrene sulfonate)-grafted poly(ε-caprolactone) (pNaSS-grafted PCL) films can deliver rAAV vectors coding for the reparative basic fibroblast growth factor (FGF-2) and transforming growth factor beta (TGF-ß) in human mesenchymal stromal cells (hMSCs) as a source of implantable cells in ACL lesions. Efficient and sustained rAAV-mediated reporter (red fluorescent protein) and therapeutic (FGF-2 and TGF-ß) gene overexpression was achieved in the cells for at least 21 days in particular with pNaSS-grafted PCL films relative to all other conditions (up to 5.2-fold difference). Expression of FGF-2 and TGF-ß mediated by rAAV using PCL films increased the levels of cell proliferation, the DNA contents, and the deposition of proteoglycans and of type-I and -III collagen (up to 2.9-fold difference) over time in the cells with higher levels of transcription factor expression (Mohawk, Scleraxis) (up to 1.9-fold difference), without activation of inflammatory tumor necrosis alpha especially when using pNaSS-grafted PCL films compared with the controls. Overall, the effects mediated by TGF-ß were higher than those promoted by FGF-2, possibly due to higher levels of gene expression achieved upon rAAV gene transfer. This study shows the potential of using functionalized PCL films to apply rAAV vectors for ACL repair.

Locally Directed Recombinant Adeno- Associated Virus-Mediated IGF-1 Gene Therapy Enhances Osteochondral Repair and Counteracts Early Osteoarthritis In Vivo.

BACKGROUND: Restoration of osteochondral defects is critical, because osteoarthritis (OA) can arise. HYPOTHESIS: Overexpression of insulin-like growth factor 1 (IGF-1) via recombinant adeno-associated viral (rAAV) vectors (rAAV-IGF-1) would improve osteochondral repair and reduce parameters of early perifocal OA in sheep after 6 months in vivo. STUDY DESIGN: Controlled laboratory study. METHODS: Osteochondral defects were created in the femoral trochlea of adult sheep and treated with rAAV-IGF-1 or rAAV-lacZ (control) (24 defects in 6 knees per group). After 6 months in vivo, osteochondral repair and perifocal OA were assessed by well-established macroscopic, histological, and immunohistochemical scoring systems as well as biochemical and micro-computed tomography evaluations. RESULTS: Application of rAAV-IGF-1 led to prolonged (6 months) IGF-1 overexpression without adverse effects, maintaining a significantly superior overall cartilage repair, together with significantly improved defect filling, extracellular matrix staining, cellular morphology, and surface architecture compared with rAAV-lacZ. Expression of type II collagen significantly increased and that of type I collagen significantly decreased. Subchondral bone repair and tidemark formation were significantly improved, and subchondral bone plate thickness and subarticular spongiosa mineral density returned to normal. The OA parameters of perifocal structure, cell cloning, and matrix staining were significantly better preserved upon rAAV-IGF-1 compared with rAAV-lacZ. Novel mechanistic associations between parameters of osteochondral repair and OA were identified. CONCLUSION: Local rAAV-mediated IGF-1 overexpression enhanced osteochondral repair and ameliorated parameters of perifocal early OA. CLINICAL RELEVANCE: IGF-1 gene therapy may be beneficial in repair of focal osteochondral defects and prevention of perifocal OA.

Comparison of visual outcomes in patients implanted with Tecnis Eyhance ICB00 and 1-Piece ZCB00 monofocal intraocular lenses.

PURPOSE: To compare the visual outcomes and monocular defocus curve of a new monofocal Tecnis Eyhance IOL (Tecnis ICB00) with Tecnis 1 single piece (ZCB00). METHODS: Eighty patients diagnosed with cataract were divided into two groups: Tecnis ICB00 (n = 40) and ZCB00 (n = 40). The visual outcome was evaluated using the following parameters: uncorrected distance visual acuity (UDVA), uncorrected intermediate visual acuity (UIVA), uncorrected near visual acuity (UNVA), corrected distance visual acuity (CDVA), distance corrected intermediate visual acuity (DCIVA), corrected near visual acuity (CNVA), uncorrected visual acuity contrast sensitivity (UVACS), best-corrected visual acuity contrast sensitivity (BCVACS), manifest refraction, and defocus curve and was compared at the 6th week and 3 months after surgery. RESULTS: The UIVA and UNVA were significantly (P < 0.05) better in ICB00 as compared with ZCB00 at 6 weeks and 3 months postoperative. The DCIVA was significantly better in ICB00 as compared with ZCB00 at 3 months postoperative (-0.015 ± 0.04 vs. 0.01 ± 0.020; P = 0.01). Regarding contrast sensitivity, UVACS and BCVACS were significantly better in ICB00 as compared with ZCB00 at 6 weeks and 3 months postoperative (P < 0.05). The defocus curves showed that the mean visual acuity of the ICB00 group was significantly better than that of the ZCB00 group at between - 0.5 D and - 2.50 D of defocus. CONCLUSION: In patients undergoing cataract surgery, Eyhance ICB00 provided better intermediate vision as compared with ZCB00.

Conjunctiva in strabismus surgery - to stitch or to stick? - A randomized clinical trial.

PURPOSE: To evaluate the clinical outcomes with fibrin glue in comparison with vicryl sutures for limbal conjunctival wound closure in strabismus surgery. METHODS: In this prospective interventional study, patients undergoing horizontal muscle strabismus surgery were randomized into two groups: the vicryl suture group and the fibrin glue group. The limbal conjunctival incisions were closed with 8-0 vicryl in the suture group and with fibrin glue in the other group. The outcomes measured were post-operative conjunctival inflammation and wound apposition, patient comfort with the help of a questionnaire, and conjunctival thickness using anterior segment optical coherence tomography (AS-OCT) for both groups at 6 weeks. RESULTS: The study included 64 eyes of 64 patients (32 eyes in each group). The fibrin glue group performed better than the vicryl suture group for most of the symptoms like redness, irritation, watering, and foreign body sensation till 2 weeks post-operatively ( P < 0.001), after which both the groups performed similarly. As for clinical signs, no significant difference was noted between the two groups, except for conjunctival hyperemia, which was significantly lesser in the fibrin glue group at 2 weeks post-operatively ( P < 0.001). The conjunctival thickness measured at 6 weeks using AS-OCT revealed that the thickness increased significantly in the suture group compared to that in the glue group ( P < 0.001 medial site, P = 0.004 lateral site). CONCLUSION: Because of greater patient comfort and reduced inflammation associated with fibrin glue, it may be considered as a procedure of choice for conjunctival wound closure in strabismus surgery in the absence of the cost constraints.

WATCHMEN: a case report highlighting the closure of a bilobed left atrial appendage using two WATCHMAN-FLX devices.

Background: Left atrial appendage occlusion (LAAO) performed percutaneously has emerged as a widely accepted method for stroke prevention, offering a viable alternative to anticoagulation. Numerous studies have demonstrated the effectiveness and safety of this procedure. However, in certain cases, the use of a single LAAO device may not adequately achieve optimal closure due to variations in the anatomy of the left atrial appendage (LAA). Case summary: In this manuscript, we highlight the successful closure of a bilobed LAA with a large ostium utilizing two WATCHMAN™ FLX devices and using the double sheath technique. The aim was to achieve optimal closure and address the unique anatomical characteristics of the patient's LAA. Discussion: The utilization of two LAAO devices in bilobed appendage anatomy, where a single device may not be sufficient, is possible, although it poses a challenge because of the lack of technical expertise and limited published evidence. Transoesophageal imaging can serve as a valuable tool for assessing the precise anatomy of the LAA and guide the selection and placement of the occlusion devices.

Guide extension catheters: Review of technology and future directions.

Although Percutaneous Coronary Intervention (PCI) has revolutionized the management of CAD, the deliverability of devices including balloons, specialty balloons, stents, atherectomy catheters, thrombectomy devices, and intravascular lithotripsy devices has become a common challenge faced by interventional cardiologists. Guide Extension Catheters (GECs) have been developed and are now widely used to create improved backup support to allow the advancement of interventional equipment required for the PCI. Improved lesion preparation, plaque modification (e.g., with atherectomy), and Guide Extension Catheters (GEC), also called as Mother-Child Technique, has proven critical to procedural success in complex cases. In this review, we discuss the role and limitations of current guide extension devices, with a brief discussion of next-generation GEC.

Melanoma With Cardiac Metastasis.

Melanoma is considered a masquerader of many diseases owing to its potential to metastasize to many organs. Several malignancies can metastasize to the heart including malignant melanoma. Historically, antemortem diagnosis of cardiac involvement of melanoma is not common, but with significant improvement in imaging modalities, the diagnosis can now be made early and accurately, aiding in treatment and improved survival. We present a case of a 36-year-old man with brief neurological symptoms and subsequent diagnosis of cerebrovascular accident (CVA). Cardiac imaging revealed incidental findings of right and left ventricular masses and lymph node biopsy, confirming metastatic melanoma. Cardioembolic etiology was suspected for his CVA. Prompt immunotherapy was initiated with improvement in his clinical condition.

A Photopolymerizable Biocompatible Hyaluronic Acid Hydrogel Promotes Early Articular Cartilage Repair in a Minipig Model In Vivo.

Articular cartilage defects represent an unsolved clinical challenge. Photopolymerizable hydrogels are attractive candidates supporting repair. This study investigates the short-term safety and efficacy of two novel hyaluronic acid (HA)-triethylene glycol (TEG)-coumarin hydrogels photocrosslinked in situ in a clinically relevant large animal model. It is hypothesized that HA-hydrogel-augmented microfracture (MFX) is superior to MFX in enhancing early cartilage repair, and that the molar degree of substitution and concentration of HA affects repair. Chondral full-thickness defects in the knees of adult minipigs are treated with either 1) debridement (No MFX), 2) debridement and MFX, 3) debridement, MFX, and HA hydrogel (30% molar derivatization, 30 mg mL-1 HA; F3) (MFX+F3), and 4) debridement, MFX, and HA hydrogel (40% molar derivatization, 20 mg mL-1 HA; F4) (MFX+F4). After 8 weeks postoperatively, MFX+F3 significantly improves total macroscopic and histological scores compared with all other groups without negative effects, besides significantly enhancing the individual repair parameters "defect architecture," "repair tissue surface" (compared with No MFX, MFX), and "subchondral bone" (compared with MFX). These data indicate that photopolymerizable HA hydrogels enable a favorable metastable microenvironment promoting early chondrogenesis in vivo. This work also uncovers a mechanism for effective HA-augmented cartilage repair by combining lower molar derivatization with higher concentrations.

rAAV TGF-ß and FGF-2 Overexpression via pNaSS-Grafted PCL Films Stimulates the Reparative Activities of Human ACL Fibroblasts.

Lesions in the human anterior cruciate ligament (ACL) are frequent, unsolved clinical issues due to the limited self-healing ability of the ACL and lack of treatments supporting full, durable ACL repair. Gene therapy guided through the use of biomaterials may steadily activate the processes of repair in sites of ACL injury. The goal of the present study was to test the hypothesis that functionalized poly(sodium styrene sulfonate)-grafted poly(ε-caprolactone) (pNaSS-grafted PCL) films can effectively deliver recombinant adeno-associated virus (rAAV) vectors as a means of overexpressing two reparative factors (transforming growth factor beta-TGF-ß and basic fibroblast growth factor-FGF-2) in primary human ACL fibroblasts. Effective, durable rAAV reporter red fluorescent protein and candidate TGF-ß and FGF-2 gene overexpression was achieved in the cells for at least 21 days, especially when pNaSS-grafted PCL films were used versus control conditions, such as ungrafted films and systems lacking vectors or films (between 1.8- and 5.2-fold differences), showing interactive regulation of growth factor production. The expression of TGF-ß and FGF-2 from rAAV via PCL films safely enhanced extracellular matrix depositions of type-I/-III collagen, proteoglycans/decorin, and tenascin-C (between 1.4- and 4.5-fold differences) in the cells over time with increased levels of expression of the specific transcription factors Mohawk and scleraxis (between 1.7- and 3.7-fold differences) and without the activation of the inflammatory mediators IL-1ß and TNF-α, most particularly with pNaSS-grafted PCL films relative to the controls. This work shows the value of combining rAAV gene therapy with functionalized PCL films to enhance ACL repair.

Cytotoxic effects of different mouthwash solutions on primary human articular chondrocytes and normal human articular cartilage - an in vitro study.

OBJECTIVES: To compare the cytotoxicity of octenidine dihydrochloride and chlorhexidine gluconate at different concentrations on primary human articular chondrocytes and cartilage. MATERIALS AND METHODS: Primary cultures of human normal adult articular chondrocytes were exposed to octenidine dihydrochloride (0.001562%, 0.003125%, 0.00625%, 0.0125%, 0.025%, 0.05%, and 0.1%), chlorhexidine gluconate (0.003125%, 0.00625%, 0.0125%, 0.025%, 0.05%, 0.1%, and 0.2%), and control (Dulbecco's modified Eagle medium or phosphate-buffered saline) for 30 s. Normal human articular cartilage explants were exposed to octenidine dihydrochloride (0.1% versus control) and chlorhexidine gluconate (0.1% versus control) for 30 s. The viability of human articular chondrocytes was measured by Trypan blue staining, Cell Proliferation Reagent WST-1, and Live/Dead staining. The proliferation of human chondrocytes was measured using the Cell Proliferation Reagent WST-1. The viability of human articular cartilage explants was measured by using Live/Dead staining. RESULTS: Octenidine dihydrochloride and chlorhexidine gluconate exposure decreased cell viability and proliferation in a dose-dependent manner in primary human articular chondrocytes. Octenidine dihydrochloride and chlorhexidine gluconate exposure decreased cell viability in human articular cartilage explant cultures. CONCLUSION: The degree of toxicity varied between octenidine dihydrochloride and chlorhexidine gluconate, with chlorhexidine gluconate being less toxic than octenidine dihydrochloride at the same concentration. Additionally, both octenidine dihydrochloride and chlorhexidine gluconate evaluation had cytotoxic effects on human articular cartilage. Therefore, dosing for the antimicrobial mouthwash ingredients administration would ideally be determined to remain below IC50. CLINICAL RELEVANCE: These data support the in vitro safety of antimicrobial mouthwashes on primary adult human articular chondrocytes.

Management of Atrial Fibrillation Post Transcatheter Aortic Valve Implantation.

Atrial fibrillation (AF) is a common complication in patients who underwent transcatheter aortic valve implantation. Some of these patients have preexisting AF as well. The management of these patients is complex, especially after the procedure, when there is a sudden change in hemodynamics. There are no established guidelines about the management of the patients who underwent transcatheter aortic valve replacement with preexisting or new-onset AF. This review article discusses the management of these patients with rate and rhythm control strategies with medications. This article also highlights the role of newer oral anticoagulation medications and left atrial occlusion devices to prevent stroke after the procedure. We will also discuss new advances in the care of this patient population to prevent the occurrence of AF after transcatheter aortic valve implantation. In conclusion, this article is a synopsis of both pharmacologic and device interventions for the management of AF in patients who underwent transcatheter aortic valve replacement.

Intra-articular injection of rAAV-hFGF-2 ameliorates monosodium iodoacetate-induced osteoarthritis in rats via inhibiting TLR-4 signaling and activating TIMP-1.

Osteoarthritis (OA) is a chronic debilitating degenerative disorder leading to structural, and functional anomaly of the joint. The present study tests the hypothesis that overexpression of the basic fibroblast growth factor (FGF-2) via direct rAAV-mediated gene transfer suppresses monosodium iodoacetate (MIA)-induced knee OA in rats relative to control (reporter rAAV-lacZ vector) gene transfer by intra-articular injection. Rats were treated with 20 µl rAAV-hFGF-2 on weekly basis; on days 7, 14, and 21 after single intra-articular injection of MIA (3 mg/50 µl saline). FGF-2 reduced knee joint swelling and improved motor performance and muscle coordination as evidenced by increased distance travelled, mean speed, rearing frequency in open field test (OFT) as well as fall-off latency in rotarod test together with reduced immobility time in OFT. Moreover, FGF-2 attenuated MIA-related radiological and histological alterations. Indeed, FGF-2 decreased knee joint inflammatory biomarker as demonstrated by reduced mRNA expression of toll like receptor (TLR)-4 and its downstream mediators such as tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1ß) and high motility group box (HMGB) 1. In parallel, FGF-2 attenuated knee joint degradation biomarkers as reflected by the downregulation of ADAMTS-5 mRNA expression and matrix metalloproteinase 13 (MMP-13) content together with the up-regulation of tissue inhibitor of metalloproteinase (TIMP)-1 mRNA expression. These findings suggest a potential therapeutic role for FGF-2 against MIA-induced knee OA in rats via inhibition of TLR4 signaling and activating TIMP-1, resulting in down-regulation of ADAMTS-5 and MMP-13.

Advanced Gene Therapy Strategies for the Repair of ACL Injuries.

The anterior cruciate ligament (ACL), the principal ligament for stabilization of the knee, is highly predisposed to injury in the human population. As a result of its poor intrinsic healing capacities, surgical intervention is generally necessary to repair ACL lesions, yet the outcomes are never fully satisfactory in terms of long-lasting, complete, and safe repair. Gene therapy, based on the transfer of therapeutic genetic sequences via a gene vector, is a potent tool to durably and adeptly enhance the processes of ACL repair and has been reported for its workability in various experimental models relevant to ACL injuries in vitro, in situ, and in vivo. As critical hurdles to the effective and safe translation of gene therapy for clinical applications still remain, including physiological barriers and host immune responses, biomaterial-guided gene therapy inspired by drug delivery systems has been further developed to protect and improve the classical procedures of gene transfer in the future treatment of ACL injuries in patients, as critically presented here.

Coronary Arteriovenous Fistula Originating From the Left Main Coronary Artery.

We report a case of coronary artery fistula arising from the left main coronary artery in a 62-year-old patient presenting with atrial fibrillation. He underwent a transthoracic echocardiogram which suggested a possible coronary artery fistula. Cardiac computed tomographic angiography and cardiac catheterization confirmed the diagnosis. Coronary artery fistula originated from the left main coronary artery, which is rare and terminated in the coronary sinus. Multi-modality imaging helps to delineate anatomy and decide treatment options. Small asymptomatic fistulas do not require treatment, and large or symptomatic fistulas need closure. Our patient was asymptomatic, and we opted for conservative management with close outpatient echocardiographic monitoring.

Effects of Recombinant Adeno-Associated Virus-Mediated Overexpression of Bone Morphogenetic Protein 3 on the Chondrogenic Fate of Human Bone Marrow-Derived Mesenchymal Stromal Cells.

Implantation of genetically modified chondrogenically competent human bone marrow-derived mesenchymal stromal cells (hMSCs) is an attractive strategy to improve cartilage repair. The goal of this study was to examine the potential benefits of transferring a sequence coding for the bone morphogenetic protein 3 (BMP-3) that modulates bone and cartilage formation, using recombinant adeno-associated virus (rAAV) vectors on the chondroreparative activities of hMSCs. Undifferentiated and chondrogenically induced primary human MSCs were treated with an rAAV-hBMP-3 construct to evaluate its effects on the proliferative, metabolic, and chondrogenic activities of the cells compared with control (reporter rAAV-lacZ vector) condition. Effective BMP-3 expression was noted both in undifferentiated and chondrogenically differentiated cells in the presence of rAAV-hBMP-3 relative to rAAV-lacZ, stimulating cell proliferation and extracellular matrix (proteoglycans, type-II collagen) deposition together with higher levels of chondrogenic sex-determining region Y-type high-mobility group box 9 (SOX9) expression. rAAV-hBMP-3 also advantageously decreased terminal differentiation, hypertrophy, and osteogenesis (type-I/-X collagen and alkaline phosphatase expression), with reduced levels of osteoblast-related runt-related transcription factor 2 (RUNX-2) transcription factor and ß-catenin (osteodifferentiation mediator) and enhanced parathyroid hormone-related protein expression (inhibitor of hypertrophic maturation, calcification, and bone formation). This study shows the advantage of modifying hMSCs with rAAV-hBMP-3 to trigger adapted chondroreparative activities as a source of improved cells for transplantation protocols in cartilage defects.

Pull-down of Biotinylated RNA and Associated Proteins.

Mapping networks of RNA-protein interactions in cells is essential for understanding the inner workings of many biological processes, including RNA processing, trafficking, and translation. Current in vivo methods for studying protein-RNA interactions rely mostly on purification of poly(A) transcripts, which represent only ~2-3% of total RNAs (Figure 1). Alternate robust methods for tagging RNA molecules with an RNA aptamer (e.g., MS2-, U1A- and biotin-RNA aptamer) and capturing the RNA-protein complex by the respective aptamer-specific partner are not extensively studied. Here, we describe a protocol (Figure 2) in which a biotin-RNA aptamer, referred to as the RNA mimic of biotin (RMB), was conjugated separately to two small RNA secondary structures that contribute to trafficking and translating HAC1 mRNA in the budding yeast Saccharomyces cerevisiae. The RMB-tagged RNA was expressed in yeast cells from a constitutive promoter. The biotinylated RNA bound to proteins was pulled down from the cell lysate by streptavidin agarose beads. RNA was detected by RT-PCR (Figure 3) and associated proteins by mass spectrometry (Figure 4). Our findings show that an RNA aptamer tag to RNA molecule is an effective method to explore the functional roles of RNA-protein networks in vivo.

Advances in Human Mitochondria-Based Therapies.

Mitochondria are the key biological generators of eukaryotic cells, controlling the energy supply while providing many important biosynthetic intermediates. Mitochondria act as a dynamic, functionally and structurally interconnected network hub closely integrated with other cellular compartments via biomembrane systems, transmitting biological information by shuttling between cells and tissues. Defects and dysregulation of mitochondrial functions are critically involved in pathological mechanisms contributing to aging, cancer, inflammation, neurodegenerative diseases, and other severe human diseases. Mediating and rejuvenating the mitochondria may therefore be of significant benefit to prevent, reverse, and even treat such pathological conditions in patients. The goal of this review is to present the most advanced strategies using mitochondria to manage such disorders and to further explore innovative approaches in the field of human mitochondria-based therapies.

Competencies for Point-of-care Ultrasonography in ICU: An ISCCM Expert Panel Practice Recommendation.

How to cite this article: Srinivasan S, Kumar PG, Govil D, Gupta S, Kumar V, Pichamuthu K, et al. Competencies for Point-of-care Ultrasonography in ICU: An ISCCM Expert Panel Practice Recommendation. Indian J Crit Care Med 2022;26(S2):S7-S12.

rAAV-Mediated sox9 Overexpression Improves the Repair of Osteochondral Defects in a Clinically Relevant Large Animal Model Over Time In Vivo and Reduces Perifocal Osteoarthritic Changes.

BACKGROUND: Gene transfer of the transcription factor SOX9 with clinically adapted recombinant adeno-associated virus (rAAV) vectors offers a powerful tool to durably enhance the repair process at sites of osteochondral injuries and counteract the development of perifocal osteoarthritis (OA) in the adjacent articular cartilage. PURPOSE: To examine the ability of an rAAV sox9 construct to improve the repair of focal osteochondral defects and oppose perifocal OA development over time in a large translational model relative to control gene transfer. STUDY DESIGN: Controlled laboratory study. METHODS: Standardized osteochondral defects created in the knee joints of adult sheep were treated with rAAV-FLAG-hsox9 relative to control (reporter) rAAV-lacZ gene transfer. Osteochondral repair and degenerative changes in the adjacent cartilage were monitored using macroscopic, histological, immunohistological, and biochemical evaluations after 6 months. The microarchitecture of the subchondral bone was assessed by micro-computed tomography. RESULTS: Effective, prolonged sox9 overexpression via rAAV was significantly achieved in the defects after 6 months versus rAAV-lacZ treatment. The application of rAAV-FLAG-hsox9 improved the individual parameters of defect filling, matrix staining, cellular morphology, defect architecture, surface architecture, subchondral bone, and tidemark as well as the overall score of cartilage repair in the defects compared with rAAV-lacZ. The overexpression of sox9 led to higher levels of proteoglycan production, stronger type II collagen deposition, and reduced type I collagen immunoreactivity in the sox9- versus lacZ-treated defects, together with decreased cell densities and DNA content. rAAV-FLAG-hsox9 enhanced semiquantitative histological subchondral bone repair, while the microstructure of the incompletely restored subchondral bone in the sox9 defects was not different from that in the lacZ defects. The articular cartilage adjacent to the sox9-treated defects showed reduced histological signs of perifocal OA changes versus rAAV-lacZ. CONCLUSION: rAAV-mediated sox9 gene transfer enhanced osteochondral repair in sheep after 6 months and reduced perifocal OA changes. These results underline the potential of rAAV-FLAG-hsox9 as a therapeutic tool to treat cartilage defects and afford protection against OA. CLINICAL RELEVANCE: The delivery of therapeutic rAAV sox9 to sites of focal injuries may offer a novel, convenient tool to enhance the repair of osteochondral defects involving both the articular cartilage and the underlying subchondral bone and provide a protective role by reducing the extent of perifocal OA.