Fig. (6) IGFBP-4 does not alter the thickness of the dermis or the collagen bundles. Human skin explants were treated as in Fig. (3) except that skin explants were injected with control cAd, Ad3, Ad5, or Ad expressing IGFBP-4 (Ad4). (A) Dermal thickness was measured in skin tissues one week post-injection. (B) Collagen bundle thickness was measured in skin tissues one week post-injection. *p < 0.02; **p < 0.03 ***p< 0.04. Panel A: H & E, 20X; Panel B: H & E, 800X.