Antigenic and morphologic regeneration of epidermal basement membrane in short term organ culture of human skin.

In fetal life the development of bullous pemphigoid antigen is preceded by a morphologically detectable basement membrane zone (BMZ). The present study investigated the possibility that similar morphologic and antigenic changes of the BMZ occur in short term organ culture of human skin. Twenty small pieces from each of four neonatal foreskin specimens were cultured under standard conditions. At regular intervals two pieces from each specimen were removed. One piece was frozen and cryostat sections were processed for indirect immunofluorescence using a patient's serum that was proven to have circulating pemphigoid IgG antibodies. Additional sections were stained with periodic acid-Schiff and hematoxylin and eosin. The other piece was processed for electron microscopic examination. Morphologically the BMZ started degenerating after 24 hours. Regeneration started on the 4th day and reached an optimal level on the 5th day. Chance of the immunofluorescence line at the BMZ began with a slight weakening at 24 hours followed by progressive widening and breakage until the 4th day when fluorescence was no longer detectable. Except for a few punctate areas immunofluorescence remained absent on the 5th day. Sixth day specimens, however, revealed reappearance of the immunofluorescence line in a continuous pattern. By the 7th day a second morphologic and antigenic degeneration started at the BMZ. This lag between the morphologic and antigenic regeneration of the BMZ in organ culture although shorter is comparable to the one observed during the development of the BMZ in fetal life.