ARACHIDONIC-ACID ACTIVATABLE ELECTROGENIC H-LYMPHOCYTES( TRANSPORT INTHE ABSENCE OF CYTOCHROME B(558) IN HUMAN T)

To test the suggested structural relationship between the electrogenic H+ transporting system and the NADPH oxidase of phagocytes, the exist ence of the enzyme and the transport process was investigated in human tonsillar T lymphocytes. It is shown that tonsillar T cells possess a n arachidonic acid activatable, Cd2-- and Zn2+-sensitive electrogenic H+ efflux pathway with similar properties as reported earlier in vario us phagocytic cells. The presence of cytochrome b(558), the membrane c omponent of the oxidase, could not be detected in tonsillar T lymphocy tes either by immunoblot or by flow cytometric analysis, It is suggest ed that the electrogenic H+ transporting pathway is structurally indep endent of the NADPH oxidase complex.