Osteoarthritis is a painful and poorly understood condition that erodes cartilage – a tough tissue that lines the surfaces of joints to allow frictionless limb movement. It affects nine million Britons and threatens twice as many in 20 years due to rising obesity and population ageing. The pictured shinbone segment (stained red), from a two-month old human embryo where bone tissue hasn’t formed yet, offers a snapshot of cartilage cells at different stages of development. They start life as small undifferentiated cells (right-hand side) before growing in size to full maturity (left), taking on different shapes depending on their location. The process is controlled by all-important microRNA molecules, discovered ten years ago. These tiny genetic strands migrate between cells and fine-tune which genes are switched on and off. Researchers are now racing to identify which microRNAs could one day be injected into joints to promote cartilage repair.
Written by Tristan Farrow
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.