APP expression and Aβ secretion in SH-SY5Y cells. A. APP expression in non-transfected, APPwt- and APPswe-transfected SH-SY5Y cells. The three bands detected with 6E10 antibody in the cell lysates are most likely isoforms of full-length APP or mature/immature APP differentially modified by glycosylation. B. Densitometric quantification shows 50% increase of APP levels in APPwt transfected SH-SY5Y cells and 100% increase in APPswe transfected cells as compared to non-transfected ones. Data presented as means ± SEM, n = 2. C. Aβ40 and Aβ42 secretion during 24 h in non-transfected, APPwt- and APPswe-transfected SH-SY5Y cells.