Figure 3: Effect of AGEs and/or alendronate on osteoclastic recruitment. (A) The photographs show representative fields of TRAP-stained macrophage/ osteoblast co-cultures, incubated either with BSA (left) or with AGEs (right). Exposure to AGEs clearly decreases the abundance of multi-nucleated TRAP (+) osteoclasts. (B) Average number of osteoclasts per field in different culture conditions. UMR-106 osteoblastic cells and Raw 264.7 macrophages were co-cultured on coverslips placed in 6-well plates for 4 days until formation of multinucleated cells. They were then incubated for an additional 4 days with 100 μg/ml of BSA or AGEs, and/or different doses of alendronate (10-8M or 10-5M). Cell monolayers were then fixed, stained with Giemsa, mounted on slides and cells with 3 or more nuclei in 50 fields at 400x were counted and averaged per field. Results are shown as the mean ± S.E.M. (* p<0.05, ** p<0.001 versus BSA alone) (# p<0.01 versus AGEs alone)