Brigitte K. Flesch

Transfusion-related acute lung injury caused by human leucocyte antigen class II antibody

Summary.  Fcγ receptor (FcγR)‐mediated destruction of immunoglobulin‐coated red blood cells (RBCs) is the underlying mechanism of haemolytic disease of the newborn. Human leucocyte antigen (HLA) antibodies in vitro are able to block monocyte FcγRs and prevent phagocytosis. The intention was to demonstrate this effect in vivo upon a volunteer. Plasma containing a non‐cytotoxic HLA‐DR alloantibody was infused into the subject. The FcγR blockade was achieved and persisted for about 2·5 d, but, unexpectedly, a mild transfusion‐related acute lung injury (TRALI) was also caused. Monocytes disappeared completely from the peripheral blood within the first hour after infusion and a mild pulmonary oedema was observed within 3–4 h. The subject recovered within 2 d.

FCGR3 variants and expression of human neutrophil antigen‐1a, ‐1b, and ‐1c in the populations of northern Germany and Uganda

BACKGROUND: Human neutrophil antigen‐1c (HNA‐1c) (SH) has been described as the third alloantigen of the Fc receptor type IIIb (FcγRIIIb) for IgG beside the known alloantigens HNA‐1a (NA1) and HNA‐1b (NA2). Controversy exists on the assignment of the HNA‐1c coding gene to the FCGR3B locus and on a possible linkage between the HNA‐1c and HNA‐1a coding genes.

Rapid typing of the human Fc gamma receptor IIA polymorphism by polymerase chain reaction amplification with allele-specific primers

BACKGROUND: The human Fc gamma receptor IIa (Fc gamma RIIa) is expressed in two polymorphic forms, Fc gamma RIIa‐H131 and Fc gamma RIIa‐R131, that differ by the replacement of histidine by arginine at position 131. This replacement is caused by a single‐nucleotide exchange of A–>G. The resulting receptor forms differ in their binding to human IgG2 and mouse IgG1, which may lead to a different immunologic defense to bacterial polysaccharides and encapsulated bacteria. STUDY DESIGN AND METHODS: A rapid and easy polymerase chain reaction(PCR) method of genotyping the Fc gamma RIIa was developed. Allele‐specific primers discriminate between the Fc gamma RIIa‐H131 and the Fc gamma RIIa‐R131 forms of the receptor. The results were compared with those obtained by another DNA‐based genotyping method, in which PCR‐amplified DNA was hybridized with allele‐specific oligonucleotides, and with a functional phagocytosis assay using mouse IgG1‐coated red cells as target antigens. RESULTS: The genotypes deduced from the PCR with allele‐specific primers were in complete accordance with those obtained by the data from the hybridization of PCR‐amplified DNA with allele‐ specific oligonucleotides. Furthermore, the Fc gamma RIIa genotypes of 28 individuals in all cases corresponded to the functional phenotypes. CONCLUSION: The use of PCR with allele‐specific primers provides a rapid and easily performed method for the determination the Fc gamma RIIa polymorphism.

HNA-1d: a new human neutrophil antigen located on Fcγ receptor IIIb associated with neonatal immune neutropenia.

Neonatal immune neutropenia (NIN) is a rare, but potentially life‐threatening, disorder caused by maternal alloantibodies recognizing paternal neutrophil antigens on fetal cells. Alloantibodies directed against the human neutrophil alloantigen system (HNA)‐1 located on Fcγ receptor IIIb (FcγRIIIb) are most frequently implicated in NIN. In this report, we describe two cases of NIN with alloantibodies against FcγRIIIb, which did not match one of the known HNA‐1a, ‐1b, or ‐1c specificities, but define a new antigen, HNA‐1d.

IMMUNOHEMATOLOGY: Rapid screening of granulocyte antibodies with a novel assay: flow cytometric granulocyte immunofluorescence test

BACKGROUND: White blood cell (WBC)‐associated antibodies can lead to severe pulmonary transfusion reactions (transfusion‐related acute lung injury [TRALI]). Investigation of a large number of blood donor samples using the standard granulocyte immunofluorescence test (GIFT) and granulocyte agglutination test (GAT) proved to be difficult to perform due to the time‐consuming process and the large quantity of test cells required. This study describes the novel flow cytometric GIFT (Flow‐GIFT) method for a rapid detection of granulocyte antibodies by flow cytometric analysis.

Expression of the CTL2 transcript variants in human peripheral blood cells and human tissues

The HNA‐3a antigen is an important antibody target in the pathophysiology of transfusion‐related acute lung injury (TRALI). It is encoded by the choline transporter‐like protein 2 (CTL2) gene, which exists in the two transcript variants TV1 and TV2, differing in the upstream promoter and coding region. Only TV1 has been demonstrated to enable choline transport across the cell membrane.

Paired crossover study of two plateletpheresis systems concerning platelet product quality and donor comfort

BACKGROUND: Two plateletpheresis cell separator systems were compared in a paired crossover study with respect to the product quality, the number of platelet (PLT) units per donation, and the donor comfort.

Rapid screening of granulocyte antibodies with a novel assay: flow cytometric granulocyte immunofluorescence test.

BACKGROUND: White blood cell (WBC)‐associated antibodies can lead to severe pulmonary transfusion reactions (transfusion‐related acute lung injury [TRALI]). Investigation of a large number of blood donor samples using the standard granulocyte immunofluorescence test (GIFT) and granulocyte agglutination test (GAT) proved to be difficult to perform due to the time‐consuming process and the large quantity of test cells required. This study describes the novel flow cytometric GIFT (Flow‐GIFT) method for a rapid detection of granulocyte antibodies by flow cytometric analysis.

FCGR3B gene frequencies and FCGR3 variants in a Chinese population from Zhejiang Province

The human neutrophil antigens HNA-1a, -1b and -1c play an important role in immune neutropenia. The frequencies of the coding FCGR3B genes were determined in different populations. New FCGR3B variants were also found in some populations. This study investigated the FCGR3B gene frequencies and FCGR3 variants in a Chinese population compared with the results of Northern Germans and African Blacks (Uganda). Our results show that the gene frequencies in 413 healthy Chinese individuals from Zhejiang Province were 0.565 for FCGR3B*1, 0.430 for FCGR3B*2 and 0.00 for FCGR3B*3. The genotype frequency of FCGR3Bnull was 0.48% (2/413). Sequencing of FCGR3 revealed that in seven out of 19 Chinese individuals, cloned and sequenced DNA fragments that exhibited variants caused by single nucleotide exchanges at one or more of the polymorphic positions 141, 147, 227, 266 and 277 in exon 3 also existed in this Chinese population. From the present study, it is concluded that the FCGR3B*1 gene is more frequent in a Chinese population from Zhejiang Province than the FCGR3B*2 gene, and the FCGR3B*3 gene seems to be absent, which is in contrast to studies in the white populations. Gene variants caused by single nucleotide exchanges were found in addition to the well-known forms, but the reason for this remains unclear.

Evidence for gene recombination in FCGR3 gene variants

Background and Objectives  The genes encoding the Fcγ receptors (FcγR) IIIa and IIIb (FCGR3A and FCGR3B) are clustered on chromosome 1 band q23–24 and exhibit allelic polymorphism. We investigated the molecular basis of additional new FCGR3 genomic variation.