Flow cytometric studies on actin polymerization in PMN cells from chronic myeloid leukemia (CML) patients.
Studies in our laboratory have shown that polymorphonuclear leucocytes (PMNL) from chronic myeloid leukemia (CML) patients are defective in chemotaxis towards a synthetic peptide, n-formyl-methionyl-leucyl-phenylalanine (FMLP), during the active phases of the disease and in remission. Actin plays a major role in cellular movements and binding of chemo-attractant to cells induces polymerization of G-actin to F-actin. We have, therefore, compared polymerization of actin in FMLP stimulated PMNL from CML patients with those from normal subjects by fluorescence microscopy and flow cytometry, using F-actin specific probe, NBD-phallacidin. Our results show that binding of FMLP to normal PMNL induces rapid conversion of G-actin to F-actin followed by depolymerization to some extent. In CML PMNL, such a biphasic response is not seen. Conversion of G-actin to F-actin is slower and F-actin content is significantly lower than that in normal PMNL. Moreover, organization of F-actin is different in CML PMNL as compared to that in normal PMNL.
Naik
N R
NR
Cancer Research Institute, Tata Memorial Centre, Parel, Bombay, India.
Bhisey
A N
AN
Advani
S H
SH
D000199:Actins / Q000378:metabolism*; D000546:Amanitins; D005434:Flow Cytometry; D006801:Humans; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood*; D008856:Microscopy, Fluorescence; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000378:metabolism / Q000494:pharmacology; D009504:Neutrophils / Q000378:metabolism*; D011108:Polymers
D000199:Actins; D000546:Amanitins; D011108:Polymers; D009240:N-Formylmethionine Leucyl-Phenylalanine; C028877:7-nitrobenz-2-oxa-1,3-diazole-phallacidin