Activation of the complement system in systemic sclerosis. Relationship to clinical severity.
Using newly developed techniques, we investigated the complement pathways and the extent of their activation in patients with systemic sclerosis (SSc) of both the diffuse cutaneous and limited cutaneous types. Plasma levels of the fragments C3d, C4d, and Ba were measured in patients with SSc and in matched control subjects. All fragments and ratios were higher in SSc patients than in controls (P less than 0.05), demonstrating that complement activation occurs in SSc. Levels of C3d, C3d:C3, Ba, and Ba:factor B were higher in patients with diffuse cutaneous SSc patients than in controls (P less than 0.01). C3d, C3d:C3, C4d, and C4d:C4 levels were also higher in patients with limited cutaneous SSc than in controls (P less than 0.05). These results show that complement activation occurs in SSc patients and that it reflects clinical severity. Complement activation may therefore have a pathogenetic role in SSc, and its measurement may prove useful in monitoring the disease.
Senaldi
G
G
Department of Immunology, King's College School of Medicine and Dentistry, London, United Kingdom.
Lupoli
S
S
Vergani
D
D
Black
C M
CM
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D003167:Complement Activation; D015933:Complement C3d / Q000032:analysis; D003181:Complement C4 / Q000032:analysis; D015935:Complement C4b; D011415:Complement Factor B / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000032:analysis; D012595:Scleroderma, Systemic / Q000276:immunology* / Q000473:pathology
D003181:Complement C4; D010446:Peptide Fragments; D015933:Complement C3d; D015935:Complement C4b; C032261:complement C4d; D011415:Complement Factor B