cell specificity of the measurement the results were obtained from a mixed population of hospitalised patients n 275 having both elevated and reduced levels of eosinophils in the their blood thus some patients had elevated numbers because of allergy and asthma chronic inflammatory diseases cancer etc and some had reduced numbers because of among other things acute infections in spite of the inclusion of these extremes in the calculation the relationship between number of eosinophils and the concentration of epo was linear over the entire range measured when epx was measured the corresponding correlation was r 0 93 and also with a linear relationship to the number of eosinophils over the entire range the above examples 1 3 describe neutrophils different maturation forms of neutrophils and eosinophils however the invention is not to be construed as limited to these cell types cell surface markers such as cd20 may measure b lymphocytes and cd3 t lymphocytes the cell surface markers cd4 and cd8 may be used to measure different lymphocyte populations determination of ratios is especially interesting for myeloid cells as described in example 2 but also for various subpopulations of lymphocytes borregaard n heiple j m simons e r et al subcellular localization of the b cytochrome component of the human neutrophil microbicidal oxidase translocation during activation j cell biol 1983 97 52 61 carlson m g ch peterson c g b.