Figure 6: Immunhistochemical assays of stem cell biomarker expression in adult NP cells. Single stem cell suspensions derived from discospheres were plated on cover slips coated with 50-μg/ml laminin in chondrogenic media supplemented with 10% fetal calf serum and chondrogenic culture conditions for 14 days. A. and C. Negative controls for immunostaining of Collagen 2a (A) and Vimentin (C). B. and D. Immunohistochemistry for. B and D. The expression of the NP cell biomarkers Collagen2a (B) and Vimentin (D) in NP cells. Shown are photomicrographs taken with fluorescent confocal microscopy at 60X magnification.