Open AccessMDHM, a macrophage‐activating product of Mycoplasma fermentans , stimulates murine macrophages to synthesize nitric oxide and become tumoricidal
Author(s) -
Ruschmeyer Dorothee,
Thude Hansjörg,
Mühlradt Peter F.
Publication year - 1993
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.1993.tb00402.x
Subject(s) - nitric oxide , macrophage , nitrite , griess test , biology , microbiology and biotechnology , cell culture , mycoplasma , mastocytoma , biochemistry , in vitro , ecology , genetics , nitrate , endocrinology
In continuation of previous work on macrophage activation by a Mycoplasma fermentans ‐derived product, originally named “mycoplasma‐derived high mol. wt. material” (MDHM), we have investigated whether MDHM was capable of inducing synthesis of the reactive nitrogen intermediate nitric oxide (NO), thus rendering macrophages cytocidal. Mycoplasmas were first delipidated with acetone, and MDHM activity was then extracted with 50 mM 1‐O‐octyl‐β‐ d ‐glucopyranoside to yield a particularly active new preparation of MDHM which we have named MDHM‐D (D for detergent). In combination with IFN‐γ, MDHM‐D activated macrophages to produce reactive nitrogen intermediates and kill P815 mastocytoma cells in co‐culture. P815 target cells were chosen because they are TNF‐resistant. Macrophages from the LPS‐low responder strain C3H/HeJ were used to minimize interference from possible LPS contamination. MDHM‐D activity in this system was strictly IFN‐γ‐dependent. In the presence of 25 U/ml IFN‐γ MDHM‐D gave a half maximal response at a dilution of 1/100 000, showing a parallel concentration dependency for nitrite production and cytocidal activity.