The Landsteiner–Wiener (LW) antigen is a type of red blood cell antigen. Anti-LW appears in various situations, including alloantibodies, autoantibodies, and even transiently occurring antibodies. Anti-LW has similar characteristics to anti-D, so it can interfere with interpreting pre-transfusion tests and finding compatible blood. This paper introduces three cases in whom anti-LW was detected through antibody identification tests. All three cases were examined using the column agglutination technique with ID-DiaPanel (Bio-Rad, Hercules, CA, USA) on a LISS/Coombs card, ID-DiaPanel p (Bio-Rad) on a NaCl/Enzyme card, and ID-DiaPanel (Bio-Rad) on a LISS/Coombs card using red blood cells treated with dithiothreitol. The auto-control test, direct antiglobulin test, and umbilical cord blood test were also performed. In all three cases, the reaction with D-positive panel cells was stronger than that with the D-negative panel cells, and two of them showed a pan-agglutinated reaction in ID-DiaPanel p (Bio-Rad) with NaCl/Enzyme card. They were reported as anti-LW, and as in these cases, anti-LW can occur under a range of conditions and interfere with proper transfusion. Therefore, it is important to identify anti-LW accurately, and if anti-LW is present, the transfusion of D-negative ABO matched blood should be recommended because of the low expression of the LW-antigen. On the other hand, D-positive blood is not a contraindication when an urgent transfusion is needed.

BACKGROUND: It is very important to accurately enumerate CD34-positive (CD34+) cells for successful hematopoietic stem cell transplantation (HSCT). We evaluated the ability of the newly developed image based-immunofluorescence cell counter ADAMII (NanoEntek, Seoul, Korea) to enumerate CD34+ cells, which was improved through simultaneous CD45 analysis. METHODS: We enumerated CD34+ cells with ADAMII using 19 peripheral blood (PB) and 91 leukapheresis samples from HSCT donors. Analytical performance, including precision and linearity, was analyzed, and sample stability during storage was evaluated. Viable CD34+ cell count (vCD34) and viable CD45+ cell count (vCD45) and the percentage of viable CD34+ cells among viable CD45+ cells (CD34/CD45) as measured by ADAMII were compared with the corresponding values from two flow cytometry assays, using regression analysis. RESULTS: ADAMII demonstrated acceptable precision, as CV values of vCD34 from six samples with different counts were all < 10% (range: 3.49–9.51%). CV values of the vCD45 and CD34/45 ranged from 4.03% to 9.67% and from 2.48% to 10.07%, respectively. The linearity of vCD34 showed an excellent R 2 value (0.99) when analyzed using the intended count and flow cytometry data. The ADAMII and two flow cytometry-based assays generated very similar data for the PB and leukapheresis samples. CONCLUSIONS: ADAMII demonstrated excellent performance for use as a routine clinical assay in terms of CD34+ cell enumeration from PB and leukapheresis samples. Moreover, it could be used as a point-of-care-test for determining mobilization time and predicting an adequate apheresis stem cell product.
Blood Component Removal ; Cell Count ; Flow Cytometry ; Fluorescence ; Hematopoietic Stem Cell Transplantation ; Humans ; Leukapheresis ; Seoul ; Stem Cells ; Tissue Donors