Certain lymphoid cells contain the membrane-associated component of the phagocyte-specific NADPH oxidase

Anionic amphiphiles such as long chain unsaturated fatty acids and SDS were shown to activate the superoxide (O₂^-) procuding NADPH oxidase in a cell-free system derived from sonically disrupted phagocytes (macrophages and granulocytes). O₂^- production required the cooperation of a membrane associated component sedimenting at 48,000 x g (π) and a cytosolic factor (σ). The purpose of the present investigation was to find out whether components π and σ were also present in non-phagocytic cells that do not produce O₂^- when stimulated. It was found that the 48,000 x g pellets of guinea pig lymph node and thymus cell sonicates contained significant amounts of component π, as shown by their ability to support SDS-elecited NADPH-dependent O₂^- production when supplemented with macrophage cytosol. Lymph node and thymus π could be extracted from the membrane by 30 mM octyl glucoside, just as its macrophage-derived equivalent. Combining lymph node and thymus 48,000 x g pellet with autologous cytosol did not yield and active enzyme preparation. Also, cytosol from lymph node and thymus cells could not cooperate with macrophage 48,000 x g pellet, indicating that component σ was lacking in lymphoid cells. Neither π nor σ could be detected in guinea pig kidney, the mouse myeloma cell line MOPC 315 and the canine cell line Cf2Th. The 48,000 x g pellet of all nonphagocytic cells examined contained a b-cytochrome that resembled, by its spectral characteristics, the cytochrome b₅₅₉ thought to be characteristic of phagocytes. In macrophages, cytochrome b₅₅₉ represented 80% of b-cytochrome content of the 48,000 x g pellet, whereas in non-phagocytic cells, the equivalent material represented only 50 to 60%. There was no correlation between the presence and quantity of the cytochrome b₅₅₉-like chromophore in the 48,000 x g pellet of a particular cell type and its ability to cooperate with macrophage cytosol in SDS-elicited O₂^- production.