MULTIPLEX MESSENGER ASSAY - SIMULTANEOUS, QUANTITATIVE MEASUREMENT OFEXPRESSION OF MANY GENES IN THE CONTEXT OF T-CELL ACTIVATION

The hybridization signature approach, using colony filters and labeled complex probes, can provide high throughput measurement of gene activ ity. We describe here the implementation of this method to follow the expression levels of 47 genes in resting and activated T cells, as wel l as in epithelial cells. Using 4-fold spotting of colonies, imaging p late detection and various correction and normalization procedures, th e technique is sensitive enough to quantify expression levels for sequ ences present at 0.005% abundance in the probe. Comparison with Northe rn blotting shows good consistency between the two methods. Upon activ ation of a T cell done by an anti-CDS antibody variations ranging from 2- to 20-fold are measured, some of which had not been reported previ ously. This 'multiplex messenger assay' method, performed using availa ble commercial apparatus, can be used in many cases where simultaneous assessment of mRNA levels for many genes is of interest.