We have done RNAseq to unknown tumors in chicken. They tumors are are likely to be lymphoid tumors. I want to identify the tumor cell of origin (B-cell, T-cell, dendritic cell, macrophage,...). I tried 2 approaches: 1) I Identified 262 annotated genes with high FPKM ( > 200 as an arbitrary cut off) then I did pathway enrichment analysis using the available orthogonal genes in human (only 244 out of the initial 262). I did not have any pathognomonic signature, The lymphoid makers appears only in the low covered genes (FPKM <100). The group of gene of high coverage has a large no of ribosomal proteins. Any suggestions on this will be appreciated.
2) The second approach I tried was my trial to implement the "DeconRNASeq" R package (http://www.bioconductor.org/packages/2.12/bioc/html/DeconRNASeq.html) The package requires an expected expression profile of every cell type suspected to be seen in the heterogeneous tumor tissue. Is there a source of such expression profiles from different primary immune cells?