Serum-free culture of porcine and rabbit corneal epithelial cells.

To better define the growth requirements for corneal epithelial cells, methods for serum-free culture were established. Sheets of corneal epithelium from eyes of swine and rabbits were obtained by dispase treatment of corneal buttons, and single cells and small clumps were obtained by further dissociation with trypsin/EDTA. Growth of cells with epithelial-like morphology was readily achieved in low calcium MCDB 153 medium containing epidermal growth factor, insulin, hydrocortisone, and bovine pituitary extract.

A putative approach for gene therapy against human immunodeficiency virus (HIV).

It is proposed here that a form of intracellular immunity can be devised which would protect cells from virus infection and, in particular, could be used as a treatment for the human immunodeficiency virus (HIV) infected individual. Following in vitro immunization of naive human B lymphocytes with reverse-transcriptase (RT) or HIV transactivator protein (tat), messenger RNA (mRNA) would be isolated from these cells. Using the mRNA molecules as templates, copy DNA (cDNA) molecules encoding the RT or tat-specific immunoglobulins, are prepared and amplified by the polymerase chain reaction.

An enzyme immunoassay for estimating small numbers of cells.

In this report we describe an enzyme immunoassay for determination of cell number in small samples. The assay utilizes a commercially available monoclonal antibody that recognizes double- and single-stranded DNA and works with several different methods of cell fixation. DNA extraction is not required.

Effect of removal of glutamine and addition of dexamethasone on the activities of glutamine synthetase, ornithine decarboxylase and lactate dehydrogenase in primary cultures of forebrain and cerebellar astrocytes.

The regulation of glutamine synthetase (GS) and ornithine decarboxylase (ODC) was studied in primary cultures of two types of astrocytes derived from either newborn forebrain or 8-day-old cerebellum of the rat. In the 14-day-old cultures the specific activities of both these enzymes were about twice as great in forebrain astrocytes as in cerebellar astrocytes. Treatment with dexamethasone or removal of glutamine from the culture medium caused a marked increase in the specific activity of GS.