title: Angiotensin II type 1 receptor expression on human leukocyte subsets: a flow cytometric and RT-PCR study.
abstract: The renin-angiotensin system plays a key role in the regulation of cardiovascular functions and in particular angiotensin II type 1 receptor (AT1R)-operated pathways are involved in the modulation of inflammation in the vascular wall. In the present study we assessed the pattern of expression of AT1Rs on different human circulating leukocyte subsets. Venous blood was obtained from healthy male subjects. Leukocyte subsets were purified by immunomagnetic cell sorting or identified in whole blood using multiparametric cytometric analysis. RT-PCR analysis showed that AT1R mRNA was expressed in polymorphonuclear leukocytes (PMNs), monocytes, B-lymphocytes, and, to a lesser extent, T-lymphocytes. Flow cytometric analysis revealed that the frequency of expression of AT1Rs was: PMNs>monocytes>or=B-lymphocytes>>T-lymphocytes, while receptor density per positive cells was: PMNs>or=B-lymphocytes>T-lymphocytes>or=monocytes. AT1Rs are expressed on PMNs, monocytes, T- and B-lymphocytes, however the expression pattern is peculiar to each subset, possibly suggesting distinct roles in the various cell types. Investigating the expression and the functional role of AT1Rs on circulating leukocyte subsets, as well as their possible modifications in disease conditions before and after pharmacological treatments, is likely to provide novel clues to the comprehension of the mechanisms involved in the therapeutic efficacy of currently available agents.
authors.affiliation: Department of Clinical Medicine, University of Insubria, Varese, Italy.
authors.forename: Emanuela
authors.initials: E
authors.lastname: Rasini
authors.forename: Marco
authors.initials: M
authors.lastname: Cosentino
authors.forename: Franca
authors.initials: F
authors.lastname: Marino
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Legnaro
authors.forename: Marco
authors.initials: M
authors.lastname: Ferrari
authors.forename: Luigina
authors.initials: L
authors.lastname: Guasti
authors.forename: Achille
authors.initials: A
authors.lastname: Venco
authors.forename: Sergio
authors.initials: S
authors.lastname: Lecchini
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000378:metabolism; D005434:Flow Cytometry / Q000379:methods; D015870:Gene Expression; D006801:Humans; D017493:Leukocyte Common Antigens; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1; D012333:RNA, Messenger / Q000032:analysis; D044140:Receptor, Angiotensin, Type 1 / Q000096:biosynthesis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D044140:Receptor, Angiotensin, Type 1; D017493:Leukocyte Common Antigens; D054562:Protein Tyrosine Phosphatase, Non-Receptor Type 1