HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Thorn, R. M. Articles by Henney, C. S. Search for Related Content PubMed Articles by Thorn, R. M. Articles by Henney, C. S.

Kinetic Analysis of Target Cell Destruction by Effector T Cells

I. Delineation of Parameters Related to the Frequency and Lytic Efficiency of Killer Cells¹

From the Departments of Medicine and Microbiology of the Johns Hopkins University School of Medicine and the O'Neill Memorial Research Laboratories of the Good Samaritan Hospital, Baltimore, Maryland

Abstract

Murine cytotoxic T cell activity was evaluated in analogy with the methods used to characterize enzymes. Concordant with this analogy, the relationship between "steady-state" lytic rates and target cell ("substrate") number was described by a hyperbola, the asymptote of which was the maximum rate of lysis ("V") and was directly proportional to the number of killer cells. The number of target cells required to reach a rate of one-half V ("K") was independent of the number of effector cells, but was found to vary with the total cell concentration in the cultures.

The kinetic analogy was extended to analyze this variability by studying the inhibition of cytolysis caused by normal syngeneic lymphocytes. A value for K in the absence of non-killer cells ("K_h") was evaluated. This term, which was independent of effector cell frequency, was a measure of lytic efficiency and, as such, was used to compare various effector cell populations.

The K_h value for a number of lymphoid cell populations from identically immunized C57BL/6 mice was found to vary considerably, thereby providing direct evidence that effector populations have different lytic efficiencies. Because of this variability, the widely used practice of comparing killer cell populations solely on the basis of their relative lytic activity may often be invalid.

Footnotes

¹ This work was supported by grant AI 10280 from the National Institute of Allergy and Infectious Disease and Contract NO1-CB-43965 from the National Cancer Institute. This is communication No. 247 from the O'Neill Memorial Research Laboratories.

² Recipient of Research Fellowship Award CA 01121 from the Public Health Service.

³ Recipient of Research Career Development Award AI 70393 from the National Institute of Allergy and Infectious Diseae.