A fully automated image analyzing system was developed for the quantitative study of cells in culture. It was able to count cells, to classify cells according to their morphological characteristics and to follow cell culture development. A specific procedure was designed to process Hoffman modulation contrast images. It detects local gray level differences while using conditional dilation techniques. We were able to successfully detect aggregated unstained cells, presently a technical limit in image segmentation. Living cells can be studied in a noninvasive and nondestructive way with this system. An improved automatic focusing algorithm was developed which ensured an accurate prediction of the optimal focus position. A strictly defined sampling procedure was applied to estimate unbiasedly cell density and obtain precisely cell contours. The evaluation of the system was carried out on Chinese hamster ovary (CHO-NTR) cell cultures treated with a newly developed neurotensin agonist JMV449. Chinese hamster ovary cell division was found to be retarded 20 hours after the JMV449 treatment, while the morphology of CHO-NTR cells has already undergone significant changes 12 hours after the treatment. This image analyzing system provides the possibility to follow cell culture development (e.g., cell density evolution, cell morphological changes) under various experimental conditions.

No abstract

Iron overload has been measured in 100 hepatic biopsies by three different methods: (i) biochemical assay of the liver iron concentration (LIC), (ii) histological grading (HISTO) and (iii) automated image analysis with a Leitz Texture Analysis System by estimating two parameters, (a) the total iron area (TIA) and (b) the first grey level step (FGLS) at which the iron is detected. Image analysis appears as a specific, sensitive, quick, reproducible and valid method. 45 copyright.

Mechanically dissociated brain cells of 14 and 18-day-old mouse embryos and of mouse neonates were cultured for 3 weeks. Neurons, oligodendrocytes and astrocytes were identified at the 7th, 14th and 21st day in vitro by staining the cultures using the indirect immunoperoxidase technique with antisera directed against neuron specific enolase, galactocerebroside, myelin basic protein and glial fibrillary acidic protein. The number of neurons and oligodendrocytes was higher in embryonic cultures than in neonate cultures. The expression of some antigens was also different in the two types of culture. Our results indicate that the development of brain cells in mechanically dissociated brain cell cultures depends on the age of the animal at the time of plating.