Apoptosis: the link between autoantibodies and leuko-/lymphocytopenia in patients with lupus erythematosus.
OBJECTIVE
To analyse the relation between serum autoantibodies and leuko-/lymphocytopenia in patients with lupus erythematosus (LE).


METHODS
Laboratory routine analyses (white blood cell counts, autoantibody detection), and flow cytometry (annexin V, CD3, CD4, CD8, CD95, F(ab)2 anti-human IgG) have been performed in LE-patients versus healthy controls. In vitro, the influence of pooled serum containing anti-dsDNA antibodies has been analysed on the CD95 expression.


RESULTS
Leukocytes, lymphocytes, CD3+, CD3+ CD4+, and CD3+ CD8+ cells from LE-patients were significantly reduced compared with controls. Patients with autoantibodies had significantly lower absolute cell counts than those without. Apoptosis was increased in LE versus controls (p < 0.04). The percentage of CD95+ T-cells was increased, and the absolute number of CD95+ cells was reduced in LE. In vitro up-regulation of CD95 could be detected on T-cells of healthy donors. Induction of CD95 seems to be donor-dependent.


CONCLUSIONS
The data suggest that autoantibodies may be associated with blood cytopenias. CD95 seems to play a central role in this signalling cascade. The underlying mechanism is unclear, but seems to be autoantibody-related apoptosis induction.
Böhm
I
I
Department of Radiology, University of Bonn, Germany. i.boehm@uni-bonn.de
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000276:immunology*; D017209:Apoptosis / Q000502:physiology*; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D002648:Child; D018450:Disease Progression; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007970:Leukopenia / Q000175:diagnosis*; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis / Q000276:immunology*; D008231:Lymphopenia / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D011336:Probability; D012016:Reference Values; D012307:Risk Factors; D012494:Sampling Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013601:T-Lymphocytes / Q000276:immunology
D015703:Antigens, CD; D001323:Autoantibodies; D015415:Biomarkers