Organotypic Differentiation Research Articles

Metanephric development in serum-free organ culture.

A new mouse metanephric organ culture system has been developed to study mammalian renal development. The system permits in vitro organotypic differentiation in a serum-free, hormone supplemented medium consisting of Dulbecco's minimal essential medium (MEM) and Ham's F12 medium supplemented with insulin, 5 microgram/ml; PGE1, 25 ng/ml; T3, 3.2 pg/ml; hydrocortisone, 5 microgram/ml; and transferrin, 5 microgram/ml. In this system, metanephric development continues morphologically beyond the S-shaped tubule stage. A well differentiated proximal tubule forms with a well defined brush border, specialized intercellular connections, and an apical endocytic network. In addition, a unique devascularized glomerulus, with highly differentiated podocytes surrounding areas of basement membrane, forms entirely from epithelial elements. The present organ culture model goes beyond the limitations of previously described systems in that it does not require separation of nephrogenic blastema from ureteric bud, nor require animal serum or nonspecific tissue extracts for metanephric development. The model is thus suited for morphological, biochemical, and endocrinological study of normal and abnormal renal organogenesis.

Organogenetic Potentialities of Rat Intestinal Epithelioid Cell Cultures

The aim of the present study was to investigate the mesenchymal influence on cultured epithelioid cells originating from an already differentiated intestine. Epithelioid cell cultures of 6-day-old suckling rat intestine were established by sequential trypsinizations of the mucosa. Embryonic intestinal monolayers of quail cells (13 days) were used as control because of their natural cell marker. Six to thirty days after plating, both types of epithelioid cells were associated in heterospecific combination with 5 1/2-day-old chick embryonic small intestinal mesenchyme, after removal of the endoderm by collagenase treatment. In order to test the differentiation capabilities of the associations, they were grafted for 10-12 days into 3-day-old chick embryos. The results show that in such an in vivo culture system, the chimeric associations gave rise to well differentiated intestinal structures indicating that the epithelioid cell cultures derived from late embryonic or neonatal intestine will go through organotypic differentiation when recombined with an appropriate mesenchyme.

In vitro preservation of human pituitary tumours in organotypic differentiation.

Three types of human pituitary adenomas--growth hormone producing, prolactin producing, as well as endocrinologically inactive ('chromophobe') tumours--were explanted to an in vitro system for organ culture. After one month, surviving hypophyseal cells demonstrated preserved hormone activity and no dedifferentiation of cell characteristics. During the first weeks in culture, close similarity existed between in vivo and in vitro conditions with regard to cell survival/cell morphology and physiological function/hormone release.