8
Views
8
CrossRef citations to date
0
Altmetric
Original Article

Hyperthermic inactivation, recovery and induced thermotolerance of human natural killer cell lytic function

&
Pages 35-49 | Received 14 Sep 1989, Accepted 08 Mar 1990, Published online: 09 Jul 2009
 

Abstract

Natural killer (NK) cytotoxic activity in human peripheral blood mononuclear cells or preparations of large granular lymphocytes was assayed after a hyperthermia treatment. Human NK cells are very sensitive to hyperthermic inactivation; 30 min at 42°C reduced NK lytic activity toward K562 target cells by 40–50%, 43 °C by 85–90% and 44°C or 45°C by 100%, but similar treatment of the target cells did not alter their sensitivity to lysis. However, holding at 37°C allowed heated NK cells to recover their lytic activity. The extent of the recovery was inversely correlated with the temperature as well as the recovery time. Heated and subsequently recovered NK cells were more thermotolerant to loss of lytic function by a further hyperthermia exposure. About 0.65°C increase in temperature was required for a 50% loss of lysis ability in the NK cells made thermotolerant by a previous hyperthermic exposure at 43°C for 30 min. The Vmax for NK lytic activity of cells heated at 42°C for 30 min was reduced by 70% compared with that of normal NK cells. When heated cells were incubated the Vmax recovered. There are at least two heat-sensitive processes involved in NK cytotoxic activity. Cells completely inactivated for target cell lysis by a 44°C exposure still showed recognition and binding functions and acted as competitive inhibitors of unheated NK cells. Cells heated at 45°C caused less inhibition and had lower ability to recognize and bind target cells. The lytic function is therefore a more heat-sensitive process than the recognition and binding functions, but both are heat-inhibitable. Individual variations in thermal sensitivity, recovery and induced thermotolerance were evident.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.