Purpose: Dendritic cells (DC) are the most potent antigen-presenting cells
of the immune system. We have shown that DC, defined as LN-DR+ leukocytes f
rom the ascites of patients with ovarian or peritoneal carcinoma, have the
cell surface characteristics of immature cells. Moreover, p70 interleukin-1
2 has not been detected in the ascites of ovarian cancer patients in vivo.
In the current study, we examined the effects of in vitro treatment of DC f
rom peripheral blood and ascites samples of patients with ovarian cancer wi
th either cytokines or proteolytic enzymes (polyenzyme preparation). Method
s: Mononuclear leukocytes from the ascites of 15 patients or peripheral blo
od from 9 patients with epithelial ovarian cancer were cultured with tissue
culture medium containing either papain, trypsin and chymotrypsin for 5-7
days or recombinant human granulocyte-macrophage colony-stimulating factor,
tumor necrosis factor alpha and interleukin-4 (complete medium) or tissue
culture medium alone. Results: Phenotypic analysis of DC obtained on days 5
-7 of the culture showed higher proportions of CD83(+), CD40(+) and CD80(+)
cells when cultured with cytokines or enzymes as compared with DC cultured
with medium alone. Stimulation of allogeneic T cells was detected by the m
ixed leukocyte reaction (MLR) and higher concentrations of IL-12 were detec
ted after growing these cells in the presence of cytokines or enzymes as co
mpared to tissue culture medium alone. Conclusion: Our studies demonstrate
for the first time that DC obtained from the peritoneal cavity and peripher
al blood of ovarian cancer patients after culturing in the presence of a po
lyenzyme preparation, will undergo maturation. Further studies are warrante
d to determine whether polyenzyme preparations facilitate DC maturation in
vivo.