Anmeldung zur Tagung
Registration
Grußwort
Invitation
Themen
Topics
Allgemeiner Ablauf
General overview
Wissenschaftliches Programm
Scientific program
Kurse
Courses
Symposien
Symposiums
Frühstück mit Spezialisten
Breakfast with specialists
Arzthelferinnen-Fortbildung
Rahmenprogramm
Social program
DOG Information
DOG Information
Allgemeine Informationen
General Information
Autorenindex
Index of Authors
Ausstellerliste
Exhibitors
Sponsoren
Sponsors
Teilnahmegebühren
Registration fees
Impressum
The Crypt System of the Human Conjunctiva has a secretory and an immunologic function
Knop N., Knop E.
Abt. für Zellbiologie in der Anatomie, Medizinische Hochschule Hannover, D- 30625 Hannover
Objective: The normal human conjunctiva shows a system of surface
infoldings that are known as crypts. These structures are already known
from the old literature. However, except for a contribution in mucus secretion
derived from their richness in goblet cells, no distinct function has
been related to them up to now.
Methods: 53 complete normal human conjunctival sacs, obtained from
body donors at the department of anatomy, were investigated by a combined
analysis of translucent wholemounts together with section morphology,
immunohistochemistry and electron microscopy.
Results: The crypts consisted of infoldings of the surface epithelium
into the lamina propria. Tubular infoldings with roundish openings (Henle
crypts) occurred in the tarsal area and longish interwoven furrows (Stiedas
clefts) were seen in the region of the tarsal margin. In addition to these
we observed that similar crypt furrows also occurred at the lid margin
and that they were continuous with Stiedas clefts nasally and temporally.
Similar crypt furrows were also observed around the lacrimal puncta. The
crypt epithelium contained apart from numerous goblet cells also other
types of secretory cells. There were tall and slender ones with apical
secretory granula, columnar cells with a broad eosinophilic cytoplasm
and others with apical cytoplasmic protrusions, probably indicating an
apocrine mode of secretion. Conjunctival crypts were also associated with
the mucosal immune system. Lymphocytes and mostly IgA-positive plasma
cells of the diffuse conjunctiva-associated lymphoid tissue formed pericryptal
accumulations. Follicular organized lymphoid tissue with high endothelial
venules formed intercryptal arrangements encircled by crypt furrows. Intraepithelial
lymphocytes and a strong staining for IgA and its transporter molecule
secretory component (SC) were observed in the epithelium.
Conclusion: Our results show that human conjunctival crypts contain
different types of secretory cells and furthermore have an immune function
in the context of the conjunctiva-associated lymphoid tissue (CALT).