Abstract
Purpose:
We investigated the myogenesis in human extraocular muscle and compared with that in human limb muscle in vitro.<br />
Methods:
We obtained human extraocular muscle and limb muscle during extraocular muscle surgery and limb muscle biopsy. Myoblast was isolated and harvested until enough fraction of myoblast had been achieved. Myogenesis was induced with F10 medium on collagen-coated dish for 18 days. When myotube formation and multiple nucleuses fusion were observed, cells were immunostained with desmin (muscle specific protein) and myoD (determination of the myogenic lineage) using each primary antibodies at day 10. We evaluated morphologic characteristics of extraocular muscle and limb muscle and compared extraocular muscle with limb muscle using daily taken phase contrast photograph. <br />
Results:
Myoblasts fusion to form multinucleate myotube in both human extraocular muscle and limb muscle primary culture started at day 4. Immunocytochemistry for desmin and myoD were shown positively stained at day 10 in both cells. Morphologic evaluation revealed that extraocular muscle myoblasts were smaller and round shape than limb muscle myoblasts at day 0. The process of myotube formation and multinucleus fusion were similar time course in extraocular muscle and limb muscle until day 7, but total area of myotube formation and total number of nucleus in extraocular muscle was smaller than limb muscle until day 10. However, total area of myotube formation and total number of nucleus in limb muscle at day 2,4 was lower than day 10 (All, p<0.05) and total area of myotube formation and total number of nucleus in extraocular muscle at day 3,5,7 was similar to day 10(All, p>0.05).<br />
Conclusions:
We have succeeded in primary culture of human extraocular muscle myoblast and inducing myogenesis to form multinucleated myotube in vitro. Our study reflects the differences in myoblast and myogenesis between human extraocular muscle and limb muscle<br />