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 Kook, A. I. Articles by Trainin, N. Search for Related Content PubMed Articles by Kook, A. I. Articles by Trainin, N.

Intracellular Events Involved in the Induction of Immune Competence in Lymphoid Cells by a Thymus Humoral Factor¹

Department of Cell Biology, The Weizmann Institute of Science, Rehovot, Israel

Abstract

A humoral factor extracted from calf thymus (THF) restores the immunocompetence of spleen cells from neonatally thymectomized (NTx) mice to induce an in vitro graft-vs-host (GVH) response. This acquisition of immunocompetence consists of a series of biochemical events, the first of which involves an obligatory rapid increase in adenyl cyclase activity and in intracellular levels of cyclic AMP. Protein synthesis occurs as a further step in the events leading to induction of immunocompetence by THF and could be blocked by cycloheximide with the consequent abolishment of the immunocompetence of the lymphoid cells tested. The induction of competence by THF is accompanied by a simultaneous reduction in DNA synthesis resulting from the increase in intracellular cyclic AMP levels. These steps have been studied in the absence of antigenic stimulation which is not required for the induction of competence by THF. Spleen extracts prepared by a similar procedure as THF were found to be devoid of the properties described above.

Footnotes

¹ This work was supported by a grant of the Talisman Foundation, New York, and by The National Institutes of Health, Agreement NCI-G-72-3890.

² Send all correspondence to: Dr. A. I. Kook, Department of Cell Biology, The Weizmann Institute of Science, Rehovot, Israel.

³ Harold L. Korda Professor of Cancer Research.