Nice to know you're working with virus. Maybe you have the same concerns I have. Study the protein expression of a viral protein of HTLV-1, which expresses little. Using FACS is difficult to have statistics significances when measured in some PBMCs.
I was thinking of using the antibody used in FACS (Lt4) to measure this protein on another platform (ELISA, Beads, Luminescence) but it is difficult to adsorb the antibody to the solid phase.
Thinking now in immuno-PCR, will be possible to make all the liquid phase and detection by PCR ?