Mass cytometry immunostaining protocol for multiplexing clinical samples.

This is a cytometry by time-of-flight (CyTOF) staining protocol for hematopoietic-derived cells, that leverages live-cell barcoding using receptor-type tyrosine-protein phosphatase C (CD45) antibodies conjugated to metal isotopes in combination with DNA-based palladium barcoding to multiplex up to 40 samples. In this protocol, DNA-based barcoding is performed before surface and intracellular immunostaining, which reduces the batch effects that result from day-to-day variations in staining and instrument sensitivity. This protocol also reduces antibody consumption and eliminates the need for repeated instrument adjustment.