Osteoimmunological Aspects of Biomechanics

Reported by : Aviral Vatsa

Biomechanics is increasingly becoming the vital link between various biological modulations and physiological processes. Its quantification and 'predictable' nature makes biomechanical approach even more appealing.

Authours

• Katharina Kerschan-Schindl 
• , Gerold Ebenbichler

Abstract

Different endogenous and exogenous factors which interfere with bone health have been identified. Among these, physical activity that relates to regular intermittent mechanical bone loading seems to be one of the major factors controlling bone mass and the prevention of osteoporotic fractures. Moreover, an interaction between bone homeostasis and the immune system which may be modified by regular physical activity exists. Bone and immune cells share a common site of origin, the bone marrow. They are supposed to influence each other not only during maturation; osteoclasts and immune cells have a number of regulatory molecules in common including cytokines, receptors, signalling molecules, and transcription factors, which influence each other.

Chapter

Principles of Osteoimmunology

pp 109-124 Date: 19 August 2016

DOI 10.1007/978-3-319-34238-2_5

Link

Extracellular microvesicle microRNAs in children with sickle cell anaemia with divergent clinical phenotypes.

Reported by Aviral Vatsa

Khalyfa A1, Khalyfa AA1, Akbarpour M1, Connes P2,3,4,5, Romana M2,3, Lapping-Carr G6, Zhang C7, Andrade J7, Gozal D1.

Abstract

Sickle cell anaemia (SCA) is the most frequent genetic haemoglobinopathy, which exhibits a highly variable clinical course characterized by hyper-coagulable and pro-inflammatory states, as well as endothelial dysfunction. Extracellular microvesicles are released into biological fluids and play a role in modifying the functional phenotype of target cells. We hypothesized that potential differences in plasma-derived extracellular microvesicles (EV) function and cargo from SCA patients may underlie divergent clinical trajectories. Plasma EV from SCA patients with mild, intermediate and severe clinical disease course were isolated, and primary endothelial cell cultures were exposed. Endothelial cell activation, monocyte adhesion, barrier disruption and exosome cargo (microRNA microarrays) were assessed. EV disrupted the endothelial barrier and induced expression of adhesion molecules and monocyte adhesion in a SCA severity-dependent manner compared to healthy children. Microarray approaches identified a restricted signature of exosomal microRNAs that readily distinguished severe from mild SCA, as well as from healthy children. The microRNA candidates were further validated using quantitative real time polymerase chain reaction assays, and revealed putative gene targets. Circulating exosomal microRNAs may play important roles in predicting the clinical course of SCA, and in delineation of individually tailored, mechanistically-based clinical treatment approaches of SCA patients in the near future

Br J Haematol. 2016 May 10. doi: 10.1111/bjh.14104. [Epub ahead of print]