The bone marrow peptide (myelopeptide-2) abolishes induced by human leukemia HL-60 cell suppression of T lymphocytes.
Myelopeptide-2 (MP-2) Leu-Val-Val-Tyr-Pro-Trp originally isolated from the supernatant of porcine bone marrow cell culture was examined for its capacity to restore the mitogen responsiveness of human T lymphocytes inhibited by conditioned media from HL-60 leukemia cells (HL-60 CM). MP-2 added to phytohemagglutinin (PHA)-stimulated T lymphocytes together with HL-60 CM abolished the suppression of T-lymphocyte proliferative response in a dose-dependent manner. Another bone marrow hexapeptide Phe-Leu-Gly-Phe-Pro-Thr, MP-1, did not display this action in that experimental system. MP-2 was also effective being added after T-lymphocyte exposure to HL-60 CM which suggests its recovery but not protective effect on T-lymphocytes treated with tumor cell products. Flow cytometry analysis revealed HL-60 CM influence on the expression of CD3 and CD4 T-cell surface antigens. It decreased the content of CD3- and CD4-positive cells and induced the appearance of T lymphocytes with reduced density of CD3 and CD4 antigens. MP-2 was able to restore the T-cell phenotype altered by HL-60 CM. MP-2 seems to be promising in anti-tumor therapy.
Strelkov
L A
LA
Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russia.
Mikhailova
A A
AA
Sapozhnikov
A M
AM
Fonina
L A
LA
Petrov
R V
RV
D001853:Bone Marrow / Q000276:immunology*; D001854:Bone Marrow Cells; D017252:CD3 Complex / Q000378:metabolism*; D015704:CD4 Antigens / Q000378:metabolism*; D016827:CD8 Antigens / Q000502:physiology; D005434:Flow Cytometry; D018922:HL-60 Cells; D006801:Humans; D007111:Immunity, Cellular; D008213:Lymphocyte Activation / Q000187:drug effects*; D008934:Mitogens / Q000494:pharmacology; D009842:Oligopeptides; D010455:Peptides / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*; D015854:Up-Regulation
D017252:CD3 Complex; D015704:CD4 Antigens; D016827:CD8 Antigens; D008934:Mitogens; D009842:Oligopeptides; D010455:Peptides; D010835:Phytohemagglutinins; C048617:myelopeptides