Anti-polymorphonuclear neutrophil antibodies in patients with leukopenia or neutropenia.
BACKGROUND
Immune humoral neutropenia (Np) could be the consequence of anti-polymorphonuclear neutrophil (PMN) antibodies, circulating immune complexes (CIC) and/or antibodies against myeloid precursors. Granulocyte immunofluorescence test (GIFT) and a leukoagglutination technique (LAGT) assays are recommended for its diagnosis.


METHODS
Fifty adult patients with secondary Np were screened for anti-PMN. GIFT by flow cytometry from viable PMN and LAGT were employed. In addition, CIC levels, low expression of CD16(b) (CD16 (b)(low)), PMN phenotype and sera tumor necrosis factor-alpha (TNF-alpha) were also evaluated.


RESULTS
Direct IgG-PMN binding (dir-GIFT) was positive in 16% of the patients. Antibodies against autologous PMN were detected in 32% of the samples by indirect (ind)-GIFT and demonstrated in 70% of the sera by both ind-GIFT and/or LAGT. Predominance of human neutrophil alloantigen (HNA)-1b and HNA-2 expression was confirmed. CD16(b)(low) was detected in 16% of the patient's PMN and TNF-alpha in 68% of sera patients.


CONCLUSIONS
Our results suggest that diagnosis of immune Np in the laboratory may be improved by focusing on patient's PMN together with the assessment of cellular markers.
Riera
N E
NE
Citometria de Flujo-CONICET, Academia Nacional de Medicina de Buenos Aires, Ciudad Autónoma de Buenos Aires, República Argentina. nriera@hematologia.anm.edu.ar
Rosso Saltó
M
M
Galán
V
V
Canalejo
K
K
Khoury
M
M
Aixalá
M
M
Kantor
G L
GL
Vermeulen
M
M
Bengió
R
R
De Bracco
M M E
MM
D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology*; D005260:Female; D006801:Humans; D007970:Leukopenia / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009503:Neutropenia / Q000276:immunology*; D009504:Neutrophils / Q000276:immunology*
D000906:Antibodies