Positional specificity of defensin gene expression reveals paneth
cell heterogeneity in mouse small intestine
Darmoul, Dalila, and Andre J. Ouellette.
Department of Medicine, Harvard Medical School, and
Gastrointestinal Unit, Medical Services, Massachusetts General
Hospital, 50 Fruit Street, Boston, Massachusetts 02114
APStracts 3:0001G, 1996.
Cryptdins are antimicrobial peptides of the defensin family that are
expressed specifically by Paneth cells in small intestinal crypts
(Selsted, et al., J. Cell Biol. 118:929-936, 1992), and at least 17
cryptdin isoforms have been reported in mouse small intestine
(Ouellette, et al., Infect. Immun. 62:5040-5047, 1994). Analysis of
cryptdin gene expression in adult mouse small bowel revealed that the
cryptdin-4 isoform is differentially expressed along the proximal-to
-distal intestinal axis. By peptide-specific RT-PCR-based assays,
cryptdin-4 mRNA was found to be absent from the proximal small bowel,
increasing to maximal levels in the ileum. In contrast, intestinal
content of cryptdin-1 and cryptdin-5 mRNAs was equivalent in
duodenum, jejunum, and ileum, and Northern blot hybridization
experiments were consistent with both sets of data. Similarly,
individual crypts isolated from duodenum contain cryptdin-1 mRNA but
not cryptdin-4 mRNA. Taken together, the results show that Paneth
cells are heterogeneous depending upon their position along the
longitudinal axis of the small bowel. The positional specificity of
defensin gene expression suggests that cryptdins may be useful
markers for investigating the establishment and maintenance of this
epithelial lineage in the mouse small intestine.
Received 7 September 1995; accepted in final form 15 December
1995.
APS Manuscript Number G394-5.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 22 January 96