Metabolic monitoring of cells in a microplate reader

PCT No. PCT/US93/07177 Sec. 371 Date Jan. 31, 1995 Sec. 102(e) Date Jan. 31, 1995 PCT Filed Jul. 30, 1993 PCT Pub. No. WO91/03191 PCT Pub. Date Feb. 17, 1994The present invention method may be practiced with many different types of biological cells. Biological cells may be either eucaryotic or procaryotic cells. The cells may be in the form of tissue slices or tissue homogenates or may be in the form of suspensions of intact single cells. The intact single cells may be grown in cell culture, as described in the previous examples, or may be obtained from blood, other body fluids, or from tissue biopsy. The cells may be cells containing receptors transfected by recombinant DNA techniques, or alternatively may be cells naturally responding to cell-affecting agents. The cells may be fresh or may have been previously preserved by dehydration, refrigeration, or freezing. When the cells have been preserved, preservative agents (for example dimethylsulfoxide in the case of frozen cells) may be removed prior to measurement of the effect of cell-affecting agents on rates of extracellular acidification. The cells may be either plant cells or animal cells. The cells also may be obtained from fresh or salt water samples. The biological cells also may be microbial cells including bacteria, rickettsia, or mycoplasma. Also, various types of fungi, including yeast, may be employed. Other types of cells include algae, protozoans, and the like. The cells may also be unable to reproduce. That is, the cells may be made synthetically, for example by encapsulation of enzymes capable of causing a change in extracellular acidification upon providing a suitable enzyme substrate.