grenz zone

grenz zone

in histopathology, a narrow layer beneath the epidermis that is not infiltrated or involved in the same way as are the lower layers of the dermis.
[Ger. Grenze, borderline, boundary]
A well-demarcated zone of separation in the upper dermis delineated by the collagen of the flattened basal epidermis from the upper dermis, the latter of which often has a dense, usually lymphocytic infiltrate. A grenz zone is seen in granuloma faciale, lepromatous leprosy, and lymphocytoma cutis and may separate a pilar tumour or leiomyoma from atrophic overlying skin

grenz zone

a zone of relatively normal collagen demarcating the boundary between normal epidermis and a dermal lesion such as a granuloma or a neoplasm.
References in periodicals archive ?
Biopsies showed increased Grenz zone collagen, as well as increased staining for mRNA for type I collagen.
Results showed a 50-80% increase in Grenz zone collagen (upper dermal collagen) in two of the three formulations designed to optimize growth factor penetration.