title: Reduced erythrocyte complement receptor type 1 in systemic lupus erythematosus is related to a disease activity index and not to the presence or severity of renal disease.
abstract: The present study investigated the expression of the complement receptor type 1 (CR1) on the membrane of erythrocytes (CR1/E) of patients with systemic lupus erythematosus (SLE) by flow cytometry. We found a significant reduction in CR1/E numbers in SLE patients (n = 52), compared to controls (512 +/- 171 and 689 +/- 146, respectively, P = 0.0001). Reduction was more pronounced in active disease patients. The mean CR1/E number observed in patients with inactive disease was 546 +/- 163 CR1/E, while active SLE patients presented a mean of 385 +/- 133 CR1/E (P = 0.001). Patients with SLE with similar activity indexes tend to have similar CR1/E numbers, irrespective of disease severity. We also observed a trend to CR1/E reduction in severe nephritis patients. A small group of SLE patients with chronic renal failure and inactive disease showed CR1/E numbers nearly identical to controls (689 +/- 146 versus 686 +/- 123, respectively, P = 0.95). This was the only group of SLE patients with normal CR1/E numbers. These results confirm the CR1/E reduction in SLE patients as previously described, and also suggest that this reduction is related to disease activity and not to disease severity.
authors.affiliation: Hospital de Base do Distrito Federal, Brasília, Distrito Federal, Brazil.
authors.forename: C E
authors.initials: CE
authors.lastname: de Carvalho Lins
authors.forename: L S
authors.initials: LS
authors.lastname: Pereira Crott
authors.forename: J E
authors.initials: JE
authors.lastname: Teixeira
authors.forename: J E
authors.initials: JE
authors.lastname: Barbosa
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D044383:Black People; D001782:Blood Donors; D001938:Brazil; D004912:Erythrocytes / Q000276:immunology*; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood* / Q000276:immunology* / Q000503:physiopathology; D008875:Middle Aged; D009393:Nephritis / Q000097:blood / Q000276:immunology; D011951:Receptors, Complement / Q000097:blood*; D012016:Reference Values; D012720:Severity of Illness Index; D044465:White People
chemical_list: D015415:Biomarkers; D011951:Receptors, Complement