download.file(paste0(url, "/", panel_filename), destfile = panel_filename, 
  mode = "wb")

Metal Isotope Antigen Lineage Functional
1    Cd 110:114     CD3       1          0
2    In     115    CD45       1          0
3    La     139     BC1       0          0
4    Pr     141     BC2       0          0
5    Nd     142   pNFkB       0          1
6    Nd     144    pp38       0          1

panel$Antigen <- gsub("-", "_", panel$Antigen)

panel_fcs$desc <- gsub("-", "_", panel_fcs$desc)

(lineage_markers <- panel$Antigen[panel$Lineage == 1])

(functional_markers <- panel$Antigen[panel$Functional == 1])

[1] "pNFkB"  "pp38"   "pStat5" "pAkt"   "pStat1" "pSHP2"  "pZap70" "pStat3"
 [9] "pSlp76" "pBtk"   "pPlcg2" "pErk"   "pLat"   "pS6"