Expression and turnover of an interstitial matrix component of the pericryptal sheath in neonatal mice

The aim of the present study was to determine the expression and turnover of antigen 1/130, a component of the interstitial matrix associated with collagen fibrils in the pericryptal sheath, in neonatal mice (CD1). Anti-laminin was used as a control. Starting on day 9 after birth, monoclonal antibody 1/130 (Mab-1/130) or anti-laminin were either fed orogastrically or injected intraperitoneally twice daily for 3 days. Bound immunoglobulins were disclosed by indirect immunofluorescence at days 12, 16, 23, 30 and 40. Sections from duodenum, ileum and colon were incubated together on the same glass slide. At day 12, the levels of labelling in orogastrically fed animals with Mab-1/130 exhibited a proximo-distal gradient (duodenum>ileum>colon); labelling with anti-laminin was found in the duodenum only. In injected animals, the levels of labelling with both antibodies showed the same gradient (duodenum>ileum>colon). At day 23, Mab-1/130 was still detected in both groups in the duodenum and ileum, whereas anti-laminin was barely detectable and only in the duodenum. At day 30, in animals fed as above or injected intraperitoneally, Mab-1/130 was present in the duodenum at the bottom of the crypts; anti-laminin was completely absent. During the postnatal period, the turnover of antigen-1/130 appeared to be slow and, as the crypts elongated, the mesenchymal pericryptal sheath did not co-migrate with the epithelial cells.