Fig. 4From: Collagen type IV alpha 1 chain (COL4A1) expression in the developing human lungRepresentative microscopic images of the four groups and adult controls. Group 1: mainly extracellular expression of COL4A1. Group 2: general low expression of COL4A1. Group 3: mainly intracellular expression of COL4A1. Group 4: both intracellular and extracellular expression occurs (all parameters increase)Back to article page