N - Formylmethionyl - Leucyl - [ 3 H ] Phenylalanine Binding , Superoxide Release , and Chemotactic Responses of Human Blood Monocytes
نویسندگان
چکیده
Human blood monocytes comprise two subpopulations: one migrates to the chemoattractant. N-formylmethionylleucyl-phenylalanine (fMet-Leu-Phe). and has saturable binding sites for this peptide; the other does not migrate and exhibits little peptide binding. To determine if expression of binding sites was a function of monocyte maturation. we depleted human subjects of blood monocytes by leukapheresis so that the circulation was repopulated by monocytes released from the bone marrow. Preand postleukapheresis monocytes were then compared for fMet-Leu-rH]Phe binding. superoxide generation. and chemotactic responses. No significant differences in peptide
منابع مشابه
Only the chemotactic subpopulation of human blood monocytes expresses receptors for the chemotactic peptide N-formylmethionyl-leucyl-phenylalanine.
Human peripheral blood monocytes comprise a subpopulation of 20 to 40% that is capable of responding to chemoattractants and a remaining subpopulation that cannot respond. We were able to obtain 99%-pure attractant-responsive monocytes by using a newly constructed separation chamber. The binding of the radioactive chemotactic peptide N-formylmethionyl-leucyl-[3H]phenylalanine to migrating and n...
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