Effect of some constituents of chicken egg yolk lipoprotein on the growth and IgM production of human-human hybridoma cells and other human-derived cells.

Chicken egg yolk lipoprotein (YLP) was partially fractionated into some constituents, and the effect of constituents of YLP were examined on the growth and immunoglobulin (IgM and IgG) secretion of a HB4C5 human-human hybridoma cell line cultured in serum-free medium. Among the fractions, YP-1 and YP-2 fractions (LDL-rich fractions) were found to enhance the growth and IgM secretion of HB4C5 cells. The promoting activity was found in the commercial LDL. The lipid fraction in YP-2 fraction conjugated with 2-maltosyl-a-cyclodextrin was found to enhance the growth and IgM secretion of HB4C5 cells. Livetin-rich YP-3 and YP-4 fractions had no significant promoting activity. Commercial gamma-livetin and phosphatidyl choline possessed no growth-promoting activity. Phosphatidyl choline enhanced the IgM secretion of HB4C5 cells.