We discuss probable immunomodulatory consequences of surface expression of CD80 by eosinophils in conditions with marked T-cell exhaustion (e.g., multiple myeloma).
These results suggest that myeloma cell vaccination co-transferred with p53, GM-CSF and B7-1 genes may be a promising immunotherapeutic approach against MM.
Studies were therefore conducted with murine myeloma BM1 cells expressing Flt3L (membrane bound or soluble forms) or GM-CSF and the IL-12 x CD80 combination.
Up-regulation of CD80 expression in response to stimulation by human huCD40LT + interleukin (IL)-2 was significantly reduced on the DCs of patients with myeloma during stable disease (n = 9) and was absent during progressive stages (n = 7) of disease.
In preclinical studies, the human myeloma cell line U266 was infected with MSCV-hIL12.B7 and a resulting clonal cell line, U/MSCV-h12.B7, was generated with stable expression of CD80 and secreting IL-12 at 1 ng/24 h/10(6) cells.