Detailed immunophenotypic characterization of different major and minor subsets of peripheral blood cells in patients with paroxysmal nocturnal hemoglobinuria.
BACKGROUND
Paroxysmal nocturnal hemoglobinuria (PNH) is characterized by a deficient expression of glycosylphosphatidylinositol-anchored proteins (GPI-APs), due to somatic mutations of the phosphatidylinositolglycan complementation Class A (PIG-A) gene.


METHODS
In this study, the expression of a high number of GPI-APs on different subsets of peripheral blood (PB) cells from 14 PNH patients and their potential association with underlying genetic abnormalities has been analyzed.


RESULTS
This study confirms the existence of variable patterns of expression of different GPI-APs on both major and minor PB-cell subsets from PNH patients. The size of the PNH clone within PB neutrophils and monocytes was systematically higher than that of other cell populations. Genetic changes were detected in the PIG-A gene in 5 of 13 cases analyzed. Interestingly, the reactivity for many GPI-APs was significantly higher on different subsets of normal PB cells from PNH patients than those observed on healthy volunteers.


CONCLUSIONS
The best combination of markers for the diagnostic screening of PNH would include evaluation of CD14 on monocytes and of CD16 on neutrophils, although further analysis of CD55 and CD59 expression may contain additional clinically useful information. Clear association between the genetic changes detected in the PIG-A gene in 5 of 13 cases analyzed, and the phenotypic profile of PNH cells has not been found. Additionally, an abnormally higher expression of several GPI-APs among normal residual cells from PNH patients in comparison to healthy donors was observed, suggesting that factors other than the PIG-A mutation could determine the phenotypic profile of PB cells in PNH.
Hernández-Campo
Pilar M
PM
Servicio General de Citometría, Departamento de Medicina and Centro de Investigación del Cáncer, Universidad de Salamanca, Salamanca, Spain.
Almeida
Julia
J
Acevedo
María J
MJ
Sánchez
María L
ML
Alberca
Ignacio
I
Vidriales
Belén
B
Martínez
Elvira
E
Romero
Juan R
JR
Orfao
Alberto
A
D036541:ADP-ribosyl Cyclase / Q000097:blood; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000097:blood; D051927:CD24 Antigen / Q000097:blood; D018958:CD55 Antigens / Q000097:blood; D018957:CD59 Antigens / Q000097:blood; D005260:Female; D058851:GPI-Linked Proteins; D006457:Hemoglobinuria, Paroxysmal / Q000097:blood* / Q000235:genetics / Q000276:immunology*; D006801:Humans; D016130:Immunophenotyping / Q000379:methods*; D018950:Lipopolysaccharide Receptors / Q000097:blood; D008297:Male; D051916:Membrane Cofactor Protein / Q000097:blood; D008565:Membrane Proteins / Q000097:blood / Q000235:genetics; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D009154:Mutation; D009504:Neutrophils / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D017452:Receptors, IgG / Q000097:blood
D015703:Antigens, CD; D051927:CD24 Antigen; D018958:CD55 Antigens; D018957:CD59 Antigens; D058851:GPI-Linked Proteins; D018950:Lipopolysaccharide Receptors; D051916:Membrane Cofactor Protein; D008565:Membrane Proteins; D017452:Receptors, IgG; C080086:phosphatidylinositol glycan-class A protein; D036541:ADP-ribosyl Cyclase; C087521:ADP-ribosyl cyclase 2