Parathyroid hormone-related protein is a possible autocrine growth inhibitor for lymphocytes.
Adult T-cell leukemia (ATL)-related cells have the ability to produce a newly-isolated calcium-regulating protein, parathyroid hormone-related protein (PTHrP). The present study revealed that lectin-stimulated normal lymphocytes produce immunoreactive (IR)-PTHrP. When the T-cell-enriched fraction was purified from normal lymphocytes and then treated with lectin, a similar amount of IR-PTHrP was detected, suggesting that IR-PTHrP is an actual product of T-lymphocytes. A biologically active fragment of PTHrP, PTHrP(1-34), suppressed DNA synthesis in lectin-stimulated lymphocytes at concentrations greater than 50 pg/mL; the same concentration range of IR-PTHrP detected in the cultured media of lectin-stimulated lymphocytes. Therefore, it is reasonable to postulate that PTHrP is a cytokine inhibiting the cellular growth of normal lymphocytes.
Adachi
N
N
Growth Factor Division, National Cancer Center Research Institute, Tokyo, Japan.
Yamaguchi
K
K
Miyake
Y
Y
Honda
S
S
Nagasaki
K
K
Akiyama
Y
Y
Adachi
I
I
Abe
K
K
D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects*; D006131:Growth Inhibitors / Q000096:biosynthesis*; D006801:Humans; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D010281:Parathyroid Hormone / Q000096:biosynthesis*; D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments / Q000494:pharmacology; D014176:Protein Biosynthesis; D011506:Proteins / Q000302:isolation & purification / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
D006131:Growth Inhibitors; C470121:PTHLH protein, human; D010281:Parathyroid Hormone; D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments; D011506:Proteins; C054296:parathyroid hormone-related protein (1-34)