
Growing Good-Guy Blood Cells in
CultureBy Jan Suszkiw June 29, 2000A laboratory method for growing white
blood cells called macrophages may bolster studies aimed at combating pathogens
that exploit the immune systems of animals and humans. Multiplying macrophages in culture avoids the standard practice of flushing
them from fluids pumped into an animals lungs or peritoneal cavity,
according to Neil Talbot, at the Agricultural Research Services
Gene Evaluation and Mapping
Laboratory at Beltsville, Md. The work was done with Joan Lunney, Max Paape
and Mulumebet Worku of ARS Immunology and Disease Resistance
Laboratory, also at Beltsville. In humans and livestock such as pigs, the amoeba-like macrophages help
eliminate dead cells, used proteins and other refuse. They also attack
bacteria, viruses, fungi or other pathogenic organisms at infection sites. And
by wearing a dead pathogens proteins, macrophages also
mobilize the immune system's T-cells and antibody-producing B-cells. But in pigs, one such pathogen--the virus that causes porcine reproductive
and respiratory syndrome (PRRS)--actually infects macrophages to replicate
itself. Only partially controlled by existing vaccines and other measures, the
PRRS virus causes late-term abortion, stillbirths and other costly problems in
pigs. Talbot hopes veterinary researchers will find macrophage tissue-culturing
useful in deciphering the virus's biological machinery. That might reveal
weaknesses for finding new drug targets. It may also benefit medical
researchers seeking alternatives to using human macrophages derived from
cancers. Such cells differ in various ways from normal macrophages. In published research, Talbots team overcame the problem of growing
pig macrophages by first culturing precursor cells called monocytes from 10
drops of blood on a special layer of feeder cells. After several
weeks, a bumper crop of hundreds of millions of mature macrophages is ready for
storage or immediate research use. Importantly, macrophage culturing doesn't
harm animal donors and yields cells similar to those found in the animals
bodies. ARS is the
U.S. Department of Agriculture's principal
research agency. Scientific contact: Neil Talbot, ARS Gene Evaluation and Mapping
Laboratory, Beltsville, Md., phone (301) 504-8216, fax (301) 504-8414,
[email protected]. Story contacts Joan K Lunney Max J Paape Jan R Suszkiw Neil C Talbot U.S. Department of Agriculture |