Epithelial growth by rat vibrissae follicles in vitro requires mesenchymal contact via native extracellular matrix

Journal Article · Wed Aug 01 04:00:00 EDT 1990 · Journal of Investigative Dermatology; (USA)

DOI:https://doi.org/10.1111/1523-1747.ep12478002· OSTI ID:6794303

Link, R E; Paus, R; Stenn, K S; Kuklinska, E; Moellmann, G ^[1]

---

1. Yale Univ. School of Medicine, New Haven, CT (USA)

An in vitro assay utilizing the rat vibrissa anagen follicle as a model for studying the epithelial-mesenchymal interactions (EMI) in hair growth is described. Through selective disruption of the epithelial-mesenchymal interface, we investigate whether the specialized extracellular matrix (ECM) of the dermal papilla and basement membrane zone (BMZ) serves a crucial function in hair follicle EMI. Epithelial bulbs incubated intact within their follicular sheaths incorporate thymidine primarily into cells of the hair matrix and outer root sheath, as shown by autoradiography. However, after removal of its mesenchymal associations (dermal papilla and extrabulbar connective tissue), the epithelial bulb showed no incorporation. Neither externally added collagen (type I or IV) nor the basement membrane components in Matrigel could substitute for the growth supporting influence of native surrounding stroma. Mechanical separation of the bulb from the dermal papilla in the basement membrane zone inhibited thymidine incorporation by the epithelium even though mesenchyme was still in close proximity. Enzymatic digestion of the dermal papilla ECM and the basal lamina by Dispase, a fibronectinase and type IV collagenase, also inhibited bulb growth without evidence of cytotoxicity. These experiments suggest that direct epithelial to mesenchymal contact is required for the support of follicular epithelial growth in vitro and that specific ECM components, possibly fibronectin and/or type IV collagen, rather than diffusable factors alone, play a crucial role in the mechanism of hair follicle EMI. The in vitro system described here provides an alternative to developmental EMI models and may serve as a valuable tool for studying EMI in the adult mammalian organism.

• OSTI ID: 6794303
• Journal Information: Journal of Investigative Dermatology; (USA), Journal Name: Journal of Investigative Dermatology; (USA) Vol. 95:2; ISSN 0022-202X; ISSN JIDEA
• Country of Publication: United States
• Language: English

Related Subjects

550301* -- Cytology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMAL TISSUES
AUTORADIOGRAPHY
AZINES
BIOLOGICAL FUNCTIONS
BODY
COLLAGEN
DNA REPLICATION
ENZYMES
EPITHELIUM
FUNCTIONS
GROWTH
HAIR FOLLICLES
HETEROCYCLIC COMPOUNDS
HYDROLASES
IN VITRO
NUCLEIC ACID REPLICATION
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PEPTIDE HYDROLASES
PROTEINS
PYRIMIDINES
RIBOSIDES
SCLEROPROTEINS
THYMIDINE
TISSUES