Three distinct profiles of serum complement C4 proteins in pediatric systemic lupus erythematosus (SLE) patients: tight associations of complement C4 and C3 protein levels in SLE but not in healthy subjects.
The serial changes of serum complement proteins C4 and C3 in SLE were characterized in 33 pediatric SLE patients with defined C4 genotypes. Three distinct groups of C4 protein profiles were observed. The first group was characterized by persistently low C4 levels (<10 mg/dL) throughout the course of the study. Patients with this profile had mild disease manifestations and low to medium copy numbers of C4 genes. The second group featured periodic fluctuations of serum C4 protein concentrations above and below 10 mg/dL, paralleled with ups and downs of SLE disease activities. Most patients with the second profile had unequal copy numbers of C4A and C4B genes and relatively severe disease. The third group had normal serum C4 levels (>15 mg/dL) most of the time and occasionally low C4 and C3 levels that were mostly coincident with disease flares prior to effective medical treatment. Most patients in this group
Wu
Yee-Ling
YL
Columbus Children's Research Institute, The Ohio State University, Columbus, Ohio 43205 USA.
Higgins
Gloria C
GC
Rennebohm
Robert M
RM
Chung
Erwin K
EK
Yang
Yan
Y
Zhou
Bi
B
Nagaraja
Haikady N
HN
Birmingham
Dan J
DJ
Rovin
Brad H
BH
Hebert
Lee A
LA
Yu
C Yung
CY
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003176:Complement C3 / Q000276:immunology*; D015934:Complement C4a / Q000235:genetics / Q000276:immunology*; D015935:Complement C4b / Q000235:genetics / Q000276:immunology*; D005260:Female; D018628:Gene Dosage; D005838:Genotype; D006801:Humans; D007155:Immunologic Factors / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000276:immunology; D008297:Male; D009154:Mutation; D010641:Phenotype; D013223:Statistics as Topic
D003176:Complement C3; D007155:Immunologic Factors; D015934:Complement C4a; D015935:Complement C4b