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.

Happiness in dermatology: a holistic evaluation of the mental burden of skin diseases

BACKGROUND

According to the World Health Organization, mental health is a state of well-being and not merely the absence of disease. However, studies exploring subjective well-being in patients with skin diseases are very rare.

OBJECTIVES

To assess subjective well-being, i.e. 'happiness', in patients with different skin diseases and to compare them to other patient groups and healthy controls.

METHODS

A cross-sectional study was conducted from 12/2017 to 04/2019. Patients receiving in- or outpatient care for psoriasis, atopic eczema, nummular eczema, mastocytosis, skin cancer (malignant melanoma and keratinocyte carcinoma), human immunodeficiency virus (HIV) or chronic inflammatory bowel diseases (Crohn's disease and ulcerative colitis) were recruited at two hospitals in Bavaria, Germany. Healthy individuals living in or near Munich served as a control group. All participants filled in a questionnaire assessing happiness, measured as positive affect (PA), negative affect and satisfaction with life (SWL; together representing subjective well-being) and a heuristic evaluation of one's own happiness.

RESULTS

Data from 229 dermatologic patients (53.3 ± 18.5 years, 48% women), 49 patients with inflammatory bowel diseases (48.9 ± 18.7 years, 43% women), 49 patients with HIV (46 ± 10.1 years, 10% women) and 106 healthy controls (38.4 ± 13.4 years, 49% women) were analysed. Compared to the controls, dermatologic patients reported lower heuristic happiness (P = 0.023) and PA (P = 0.001) but higher SWL (P = 0.043). Patients with psoriasis and atopic eczema reported the lowest happiness, as they reported significantly lower PA (P = 0.032 and P < 0.001) and heuristic happiness (P = 0.002 and P = 0.015) than the control group. Patients with skin cancer reported higher SWL than the control group (P = 0.003). Dermatologic patients reported lower happiness than patients with HIV but reported greater happiness than patients with IBD.

CONCLUSIONS

Dermatologic patients experience lower levels of happiness, especially PA, compared to healthy controls. As PA is linked to desirable health outcomes, targeting PA could be a promising holistic approach for the treatment of skin diseases.

Comprehensive analysis of translational osteochondral repair: Focus on the histological assessment

Articular cartilage guarantees for an optimal functioning of diarthrodial joints by providing a gliding surface for smooth articulation, weight distribution, and shock absorbing while the subchondral bone plays a crucial role in its biomechanical and nutritive support. Both tissues together form the osteochondral unit. The structural assessment of the osteochondral unit is now considered the key standard procedure for evaluating articular cartilage repair in translational animal models. The aim of this review is to give a detailed overview of the different methods for a comprehensive evaluation of osteochondral repair. The main focus is on the histological assessment as the gold standard, together with immunohistochemistry, and polarized light microscopy. Additionally, standards of macroscopic, non-destructive imaging such as high resolution MRI and micro-CT, biochemical, and molecular biological evaluations are addressed. Potential pitfalls of analysis are outlined. A second focus is to suggest recommendations for osteochondral evaluation.