Scientists can accurately assess a person's natural ability to fight infections or suppress cancers with a streamlined technique developed by Agricultural Research Service immunologist Tim Kramer. The technique began with a wish he made 21 years ago on a drive through the mountains of Thailand.

Called "whole blood microculture," the new technique enables scientists to test a chemical stimulant's ability to prompt T cells to multiply in their natural milieu--blood. T cells, the player-coaches of the immune system, are a sensitive indicator of immune function.

The new technique costs an estimated 35 to 40 percent less than the standard technique, and it more than triples the number of samples technicians can handle each day. So it could lead to routine screening of infants, children, the elderly and others whose immune competence may be suspect.

The need for a quick and easy way to test people's immune competence hit Kramer in 1976. He was working at the Anemia and Malnutrition Research Center in Thailand. One day he passed through several small, remote villages while driving a previously malnourished child to her home--four hours away across very hilly terrain.

He wished then he could gather some data on how malnutrition affects cellular immunity in such remote locations. But in a make-shift laboratory in the countryside, such measurements would have been very difficult. Highly trained technicians would have had to separate T cells from blood, using expensive equipment, before they could culture and test the cells.

During the past decade, Kramer has tweaked his technique into a fool-proof measure of cellular immune competence for nutritional studies. He's still improving it to measure the chemicals immune cells use to talk to one another. A few other immunologists are developing Kramer's technique for research and clinical use.

An article about the new technique appears in the December issue of Agricultural Research magazine. It's also on the World Wide Web at:

http://www.ars.usda.gov/is/AR/archive/dec97/tcel1297.htm

Scientific contact: Tim R. Kramer, ARS Beltsville Human Nutrition Research Center, Beltsville, Md., phone (301) 504-8459 or 504-6216, fax (301) 504-9456, kramer@307.bhnrc.usda.gov.