Fig. 2

LDH isoenzyme expression in AEC2 from fibrotic IPF vs. non-fibrotic control human lungs. A Schematic of LDHA and LDHB subunit compositions in the 5 isoforms of the active LDH tetramer. B Non-denatured lysates from purified AEC2s of 3 control/non-fibrotic and 3 IPF human lung samples were separated by native gel electrophoresis and subjected to colorimetric staining for LDH activity to measure the % of each isoenzyme tetramer (LDH1 to 5) comprising total LDH in each sample. The A549 cell-line was also analyzed for comparison. C Colorimetric LDH staining after native PAGE showing separated LDH tetramer isoforms of three AEC2 sample lysates from B. D Lysates from AEC2s purified from 3 control/non-fibrotic and 3 IPF lungs were analyzed by SDS-PAGE and western blot using anti-LDHA and –LDHB antibodies. Immunoblots and average LDHA:LDHB ratio of 3 samples from each lung type are shown. LDH subunit expression was normalized to β-actin expression