EXPRESSION OF MESSENGER-RNAS OF MULTIPLE GROWTH-FACTORS AND RECEPTORSBY ASTROCYTES AND GLIOMA-CELLS - DETECTION WITH REVERSE TRANSCRIPTION-POLYMERASE CHAIN-REACTION

1. Although glial cells in culture are known to secrete growth factors and are also known to be responsive to some of them, detailed compari sons are difficult because the bulk of information was based on variou s animals of origin, developmental stages, growth properties, culture age, and culture conditions. 2. To present a unified picture of the gr owth factors and their receptors found in glial cells, we surveyed the expression of messenger RNAs of a panel of growth factors and recepto rs, using reverse transcription-polymerase chain reaction (RT-PCR), in three common glial cell types: rat astrocytes in primary culture, rat glioma line C6, and human glioma line A172. 3. We observed that norma l and neoplastic glial cells in culture express multiple growth factor s and also possess most of the receptors to these factors, suggesting multiple autocrine functions, In addition, glia produce growth factors known to be capable of acting on neurons, implicating paracrine funct ion involving glia-neuron interaction. Glial cells also produce growth factors and receptors that are capable of communicating with hematopo ietic cells, suggesting neuroimmunologic interaction. What is most int eresting is that glial cells express receptors for growth factors prev iously thought to be acting on neurons only. 4. The current study demo nstrates the feasibility of screening from a small sample a large numb er of growth factors and receptors. The method portends future clinica l application to biopsy or necropsy samples from brain tumors or patho logic brains suffering from degenerative diseases such as Alzheimer's or Parkinson's disease.