Tissue typing of cells in culture. I. Distinction between cell lines by the various patterns produced in mixed haemadsorption with selected multiparous sera.

From over 3000 sera of multiparous women about 150 were selected that reacted with some (between 1--50%) of a panel of 20--30 non-HeLa cell lines, mostly of tumour origin. In the mixed haemadsorption method the diameters of zones formed by certain sera on particular cultures were measured and scored. The haemadsorption culture patterns produced by 70--135 discriminating sera were compared in pairs with the patterns formed on other cell lines. Comparisons between replicate cultures gave 'significant' differences with 0--10% of the sera used. In these instances deviations were in one direction, whereas in every other pair comparison, deviations were in both directions. It is concluded that in cases where pair comparisons initially give only 10%, or fewer significant differences, tests using carefully selected sera or typing for HLA-antigens should be performed. When comparisons yield more than 10% significant differences and deviations occur in both directions, cultures may be considered different.