[Interaction of the synthetic immunomodulatory dipeptide bestim with murine macrophages and thymocytes].
The tritium-labeled dipeptide bestim (gamma-D-Glu-L-Trp) with a specific activity of 45 Ci/mmol was obtained by high-temperature solid-state catalytic isotope exchange. It was found that [3H]bestim binds with a high affinity to murine peritoneal macrophages (Kd 2.1 +/- 0.1 nM) and thymocytes (Kd 3.1 +/- 0.2 nM), as well as with plasma membranes isolated from these cells (Kd 18.6 +/- 0.2 and 16.7 +/- 0.3 nM, respectively). The specific binding of [3H]bestim to macrophages and thymocytes was inhibited by the unlabeled dipeptide thymogen (L-Glu-L-Trp) (Ki 0.9 +/- 0.1 and 1.1 +/- 0.1 nM, respectively). After treatment with trypsin, macrophages and thymocytes lost the ability to bind [3H]bestim. Bestim in the concentration range of 10(-10) to 10(-6) M reduced the adenylate cyclase activity in the membranes of murine macrophages and thymocytes.
Kolobov
A A
AA
Kolodkin
N I
NI
Zolotarev
Iu A
IuA
Tathill
C
C
Navolotskaia
E V
EV
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D002478:Cells, Cultured; D004151:Dipeptides / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology*; D017737:Macrophages, Peritoneal; D051379:Mice; D008807:Mice, Inbred BALB C; D011485:Protein Binding / Q000502:physiology; D013950:Thymus Gland / Q000166:cytology / Q000201:enzymology*
D004151:Dipeptides; D007155:Immunologic Factors; D000262:Adenylyl Cyclases