Lorraine Caruccio

CD177: A member of the Ly-6 gene superfamily involved with neutrophil proliferation and polycythemia vera

Genes in the Leukocyte Antigen 6 (Ly-6) superfamily encode glycosyl-phosphatidylinositol (GPI) anchored glycoproteins (gp) with conserved domains of 70 to 100 amino acids and 8 to 10 cysteine residues. Murine Ly-6 genes encode important lymphocyte and hematopoietic stem cell antigens. Recently, a new member of the human Ly-6 gene superfamily has been described, CD177. CD177 is polymorphic and has at least two alleles, PRV-1 and NB1. CD177 was first described as PRV-1, a gene that is overexpressed in neutrophils from approximately 95% of patients with polycythemia vera and from about half of patients with essential thrombocythemia. CD177 encodes NB1 gp, a 58–64 kD GPI gp that is expressed by neutrophils and neutrophil precursors. NB1 gp carries Human Neutrophil Antigen (HNA)-2a. Investigators working to identify the gene encoding NB1 gp called the CD177 allele they described NB1. NB1 gp is unusual in that neutrophils from some healthy people lack the NB1 gp completely and in most people NB1 gp is expressed by a subpopulation of neutrophils. The function of NB1 gp and the role of CD177 in the pathogenesis and clinical course of polycythemia vera and essential thrombocythemia are not yet known. However, measuring neutrophil CD177 mRNA levels has become an important marker for diagnosing the myeloproliferative disorders polycythemia vera and essential thrombocythemia.

Expression of human neutrophil antigen-2a (NB1) is increased in pregnancy.

BACKGROUND : The expression of human neutrophil antigen‐2a (HNA‐2a) or NB1 is highly variable. This study investigated variations in neutrophil expression of HNA‐2a by comparing the expression of epitopes recognized by three HNA‐2a‐specific CD177 antibodies among healthy adults and pregnant women.

Gene and microRNA analysis of neutrophils from patients with polycythemia vera and essential thrombocytosis: down-regulation of micro RNA-1 and -133a

BackgroundSince the V617F mutation in JAK2 may not be the initiating event in myeloprofilerative disorders (MPDs) we compared molecular changes in neutrophils from patients with polycythemia vera (PV) and essential thrombocythosis (ET), to neutrophils stimulated by G-CSF administration and to normal unstimulated neutrophilsMethodsA gene expression oligonucleotide microarray with more than 35,000 probes and a microRNA (miR) expression array with 827 probes were used to assess neutrophils from 6 MPD patients; 4 with PV and 2 with ET, 5 healthy subjects and 6 healthy subjects given G-CSF. In addition, neutrophil antigen expression was analyzed by flow cytometry and 64 serum protein levels were analyzed by ELISA.ResultsGene expression profiles of neutrophils from the MPD patients were similar but distinct from those of healthy subjects, either unstimulated or G-CSF-mobilized. The differentially expressed genes in MPD neutrophils were more likely to be in pathways involved with inflammation while those of G-CSF-mobilized neutrophils were more likely to belong to metabolic pathways. In MPD neutrophils the expression of CCR1 was increased and that of several NF-κB pathway genes were decreased. MicroRNA miR-133a and miR-1 in MPD neutrophils were down-regulated the most. Levels of 11 serum proteins were increased in MPD patients including MMP-10, MMP-13, VCAM, P-selectin, PDGF-BB and a CCR1 ligand, MIP-1α.ConclusionThese studies showed differential expression of genes particularly involved in inflammatory pathways including the NF-κB pathway and down-regulation of miR-133a and miR-1. These two microRNAs have been previous associated with certain cancers as well as the regulation of hyperthrophy of cardiac and skeletal muscle cells. These changes may contribute to the clinical manifestations of the MPDs.

CD177 polymorphisms: correlation between high-frequency single nucleotide polymorphisms and neutrophil surface protein expression

BACKGROUND:  Human neutrophil antigen‐2a (NB1) is located on NB1 glycoprotein, which is expressed on subpopulations of neutrophils. PRV‐1 is a gene that is over‐expressed in neutrophils from patients with polycythemia rubra vera. The gene encoding NB1 differs from PRV‐1 at four nucleotides. The purpose of this study was to determine if PRV‐1 and NB1 are alleles of the same gene or two separate genes; and, moreover, if they are alleles, to explore potential correlations to NB1 glycoprotein expression.

The gene overexpressed in polycythemia rubra vera, PRV-1, and the gene encoding a neutrophil alloantigen, NB1, are alleles of a single gene, CD177, in chromosome band 19q13.31.

BACKGROUND:  PRV‐1 mRNA is overexpressed by neutrophils from polycythemia vera patients and is homologous to NB1 a gene overexpressed in reactive neutrophilia.

A novel method using formamide for the elution of antibodies from erythrocytes

Background and Objectives Accurate identification of antibodies that sensitize red blood cells (RBCs) involves dissociating them from RBCs using an in vitro elution method that does not alter their antigen‐binding properties, and analysis of the eluates against a panel of RBCs.

Another example of a KEL1 variant red cell phenotype due to a threonine to serine change at position 193 of Kell glycoprotein.

BACKGROUND: Healthy subjects whose red blood cells (RBCs) react variably with anti‐KEL1, but strongly express other Kell blood group antigens, have been described and called KEL1 variant. A 53‐year‐old Caucasian blood donor was identified whose RBCs reacted with three monoclonal and two polyclonal anti‐KEL1 and did not react with two monoclonal and one polyclonal anti‐KEL1. The molecular basis of this phenotype was investigated.

KEL6 and KEL7 genotyping with sequence-specific primers.

BACKGROUND:  Although antibodies to Jsa and Jsb are clinically significant, reagent‐quality anti‐Jsa and anti‐Jsb are not readily available. A sequence‐specific primer–polymerase chain reaction (SSP‐PCR) genotyping assay was tested that makes use of two single‐nucleotide polymorphisms (SNPs) at positions 1910 and 2019 of KEL. These SNPs distinguish the gene encoding Jsa, KEL6; and Jsb, KEL7.