Method for epigenetic immune cell detection and counting in human blood samples for immunodiagnostics and newborn screening

A method for an improved methylation assay for identifying blood immune cells, comprising the steps of

• a) providing a sample of human blood, comprising genomic DNA of blood immune cells;
• b) treating said genomic DNA of said blood immune cells with bisulfite to convert unmethylated cytosines into uracil;
• c) amplifying said treated genomic DNA using suitable primer pairs to produce amplicons;
• and
• d) identifying said blood immune cells based on analyzing said amplicons as amplified, wherein said amplification and analysis comprise amplification and/or qPCR using primers and probes selected from at least one set select from SEQ ID NOs. 1 to 12 for CD4, SEQ ID NOs. 13 to 20 for CD8beta, SEQ ID NOs. 21 to 28 for lipoprotein receptor-related protein 5 (LRP5), SEQ ID NOs. 29 to 36 for mevalonate pyrophosphate decarboxylase (MVD), SEQ ID NOs. 37 to 44 for lipocalin-2 (LCN2), and SEQ ID NOs. 45 to 56 for CD3gamma/delta, and
• wherein a demethylation of at least one CpG position in said amplicon is indicative for at least one blood immune cell selected from CD3+ T cells, CD4+ T cells, CD8+ T cells, neutrophils, CD14+ monocytes, CD56+ NK cells, and CD19+ B cells.