A Novel Method Using Extracted Human Neutrophil Antigens From HNA Gene-Transfected Cell Lines for Detection of Antibodies Against Human Neutrophil Antigens

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 3272-3272
Author(s):  
Rie Onodera ◽  
Kazuhiro Nakamura ◽  
Kikuyo Taniguchi ◽  
Emi Kurita ◽  
Asako Hiraoka ◽  
...  
Keyword(s):  
Cell Lines ◽  
Positive Reaction ◽  
Human Neutrophil ◽  
Conflicts Of Interest ◽  
Age Distribution ◽  
Easy Method ◽  
Novel Method ◽  
Immune Neutropenia ◽  
Relationship Of ◽  
Normal Controls

Abstract Abstract 3272 Antibodies against Human Neutrophil Antigen (anti-HNA antibodies) have been implicated in immune neutropenia and transfusion-related acute lung injury. Those have been usually analyzed by Granulocyte indirect immunofluorescence test by flow-cytometry (GIFT-FCM), which requires fresh blood for panel neutrophils that cannot be preserved more than a few hours. Furthermore, specificity for anti-HNA antibodies cannot be easily identified by GIFT-FCM because of several antigens on membrane of panel neutrophil. In this study, we have developed a novel method designated as KY-Luminex Method, which was modified from Monoclonal antibody-specific immobilization of granulocyte antigens. For KY-Luminex Method, extracted human neutrophil antigens (eHNAs) were established from gene-transfected cell lines (KY-1a, -1b, -1c, -2a, -4a, -4b, -5a, -5b) that express HNA-1a, -1b, -1c, -2a, -4a, -4b, -5a, -5b, respectively. These eHNAs were immobilized by monoclonal antibodies on microspheres (eHNA-microspheres). Sera were tested to the eHNA-microspheres in wells of a 96-well microplate, respectively. The reactivities of the sera were analyzed by Luminex100. From May 2010 to March 2012, sera were obtained from 101 patients with autoimmune neutropenia in children. The age distribution was from 2 months to 72 months. Sixty-three patients were females and 38 were males. As shown in Table, the sera from 74 patients showed positive reaction both in standard GIFT-FCM and KY-Luminex method. The sera from 11 patients showed positive in GIFT-FCM, and negative in KY-Luminex. These sera finally proved to have antibodies against antigens other than neutrophil such as anti-HLA antibody. The sera from 13 patients showed negative in GIFT-FCM, and positive in KY-Luminex. The sera from 3 patients showed negative both in GIFT-FCM and KY-Luminex. Sera with positive reaction against each panel neutrophil in GIFT-FCM have tendency to react against multiple antigens in KY-luminex method. Especially, majoryty of analyzed sera had antibodies against HNA-4a, 4b, 5a and 5b. No antibodies against each antigens were detected in sera from normal controls by KY-luminex method. These results indicate that KY-luminex method has superior to GIFT-FCM in both sensitivity and specificity of anti-HNA antibodies. Furthermore, eHNA-microspheres are stable at 4 centigrade for more than a half year, and many samples such as 96 samples could be analyzes at once in simple and easy method. Table. Relationship of reactivities of patient's sera between GIFT-FCM and KY-luminex method. Data represent the number in 101 patients GIFT-FCM KY-Luminex method positive negative positive 74 11 negative 13 3 Disclosures: No relevant conflicts of interest to declare.

scholarly journals CD16b: Primary Structure of Human Neutrophil Antigen Epitopes and Their Functional Consequences

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 3680-3680
Author(s):  
Ulrich J Sachs ◽  
Angelika Reil ◽  
Piyapong Simtong ◽  
Sentot Santoso
Keyword(s):  
Cell Lines ◽  
Human Neutrophil ◽  
Conflicts Of Interest ◽  
Solid Phase ◽  
Hek293 Cells ◽  
Adhesion Assay ◽  
Wild Type ◽  
Capture Assay ◽  
Diagnostic Work ◽  
And Function

Abstract Neutrophil specific Fcg receptor IIIb (CD16b) is a glycosylphosphatidylinositol-anchored low-affinity glycoprotein that plays a significant role in phagocytosis and the clearance of immune complexes. CD16b has numerous polymorphic variants; the most relevant variants are associated with human neutrophil antigens (HNA) -1a, -1b, and -1c. HNA-1a and HNA-1b differ in four amino acids (aa) (positions 36, 65, 82 and 106). One additional aa mutation on HNA-1b at position 78 results in HNA-1c. Immunization against CD16b variants can lead to the production of alloantibodies (aabs) responsible for neonatal alloimmune neutropenia (NIN), autoimmune neutropenia of infancy (AIN) and transfusion-related acute lung injury (TRALI). The exact contribution of five aa mutations for the formation of HNA-1a, -1b and -1c and function of CD16b is currently unknown. In this study, permutation of each polymorphic aa from wild-type CD16b cDNA constructs was performed and stably expressed on HEK293 cells. In total, 3 cell lines expressing wild-type (HNA-1a, -1b and -1c) and 18 cell lines expressing mutant variants were produced; 14 derived from HNA-1a or HNA-1b (panel 1) and 4 derived from HNA-1c (panel 2). When panel 1 was tested with well-defined aabs by antigen capture assay, 4 cell lines reacted with anti-HNA-1a only, 4 with anti-HNA-1b only, 4 with both aabs, and 4 did not react with both aabs. These results indicate that aa36 and aa65 are responsible for the formation of the HNA-1a and HPA-1b epitope(s), respectively. Analysis of panel 2 showed that 2/4 mutant variants reacted with anti-HNA-1c exclusively, suggesting that the HNA-1c epitope is formed by Ala78Asp irrespective of the other polymorphic aa. To analyze the binding affinity of CD16b variants, adhesion assay onto immobilized IgG was performed. In comparison to HNA-1a, HNA-1b cells bound slightly weaker to IgG (p<0.002). In contrast, HNA-1c cells interacted significantly stronger with IgG in comparison to both, HNA-1a and -1b cells (p<0.0001). Similar results were obtained with HNA-1a, -1b and -1c recombinant proteins by direct protein-binding analysis (solid phase ELISA and Surface Plasmon Resonance). Interestingly, all mutant variants carrying HNA-1c bound also stronger to IgG than HNA-1a and -1b transfected cells. Similar results were observed with HNA-1c phenotyped neutrophils. In conclusion, although HNA-1a and HNA-1b differ in four aa positions, only two (aa36, aa65) are necessary for the complete formation of the respective epitopes. In contrast, the HNA-1c epitope is created by only one aa mutation (Ala78Asp). Furthermore, our results show that HNA-1c exhibits higher affinity to IgG compared to HNA-1a and HNA-1b forms. Accordingly, the Ala78Asp mutation is not only responsible for epitope formation, but is also involved in the regulation of CD16 affinity. Characterization of HNA-1 epitopes by tailored recombinant tools will help us to improve our diagnostic work-up in patients with suspected NIN, AIN and TRALI and our understanding on the role of CD16 polymorphism in other diseases such as, immune complex-mediated disorders. Disclosures No relevant conflicts of interest to declare.

Synthesis and Antitumor Activity Evaluation of New Phenanthrene-Based Tylophorine Derivatives

2019 ◽  
Vol 16 (6) ◽  
pp. 462-467
Author(s):  
Songtao Li ◽  
Hongling Zhao ◽  
Zhifeng Yin ◽  
Shuhua Deng ◽  
Yang Gao ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Cell Lines ◽  
Antitumor Activities ◽  
Human Carcinoma ◽  
Carcinoma Cell Lines ◽  
Structure Activity ◽  
Human Carcinoma Cell ◽  
Ic50 Values ◽  
Relationship Of

A series of new phenanthrene-based tylophorine derivatives (PBTs) were synthesized in good yield and their structures were characterized by 1H-NMR spectroscopy and ESI MS. In vitro antitumor activity of these compounds against five human carcinoma cell lines, including HCT116 (colorectal), BGC-823 (gastric), HepG-2 (hepatic), Hela (cervical) and H460 (lung) cells, was evaluated by MTT assay. Among these PBTs, compound 6b showed the highest antitumor activities against HCT116 and HepG-2 cell lines with IC50 values of 6.1 and 6.4 μM, respectively, which were comparable to that of adriamycin hydrochloride. The structure-activity relationship of these compounds was also discussed based on the results of their antitumor activity.

scholarly journals Elastase as a marker for neutrophilic myeloid cells.

1984 ◽  
Vol 32 (4) ◽  
pp. 389-394 ◽  
Author(s):  
J A Kramps ◽  
P van der Valk ◽  
M M van der Sandt ◽  
J Lindeman ◽  
C J Meijer
Keyword(s):  
Cell Lines ◽  
Neutrophil Elastase ◽  
Human Neutrophil ◽  
Myeloid Cells ◽  
Hematopoietic Cell ◽  
Human Neutrophil Elastase ◽  
Specific Marker ◽  
Neoplastic Cells ◽  
Myeloproliferative Diseases ◽  
Myelomonocytic Leukemia

The immunohistochemical results obtained with antibodies directed against human neutrophil elastase is described. It was found that neutrophil elastase can be used as a specific marker of cells of the neutrophilic lineage. In normal hematopoietic cell preparations, only promyelocytes and more differentiated myeloid cells stain positive for elastase. In acute or chronic myeloid and myelomonocytic leukemia, the same neutrophil myeloid cells stain positive, whereas neoplastic cells of the monocytoid line are negative. Using elastase in conjunction with other markers, it is possible to differentiate easily the involvement of different cell lines in myeloproliferative diseases.

scholarly journals Synthesis of Novel 2-Thioxothiazolidin-4-one and Thiazolidine-2, 4-dione Derivatives as Potential Anticancer Agents

2018 ◽  
Vol 13 (5) ◽  
pp. 1934578X1801300
Author(s):  
Alleni Suman Kumar ◽  
Rathod Aravind Kumar ◽  
Elala Pravardhan Reddy ◽  
Vavilapalli Satyanarayana ◽  
Jajula Kashanna ◽  
...  
Keyword(s):  
Anticancer Activity ◽  
Cell Lines ◽  
Cancer Cell ◽  
Anticancer Agents ◽  
Preliminary Data ◽  
Cancer Cell Lines ◽  
Structure Evolution ◽  
Model Compounds ◽  
Diverse Range ◽  
Novel Method

A variety of novel thiazolidine derivatives (2-thioxothiazolidin-4-one and thiazolidine-2, 4-dione derivatives) have been prepared by using 2,4-diphenyl-2 H-chromene-3-carbaldehyde and its derivatives as starting materials. This is the first example of the preparation of thiazolidine derivatives through this novel method. Structure evolution of the resulting thiazolidine derivatives leads to anticancer agents. Our preliminary data for some model compounds on three cancer cell lines (MCF7, A549 and B-16) suggested reasonable anticancer activity against the A549 and B-16 cell lines, with IC50 values of 20.7 and 20.4 μM, respectively. This method is operationally simple and works with a diverse range of substrates.

scholarly journals Super-Enhancer Profiling Identifies Novel Oncogenes and Therapeutic Targets in Multiple Myeloma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 362-362
Author(s):  
Jianbiao Zhou ◽  
Yunlu Jia ◽  
Tze King Tan ◽  
Tae-Hoon Chung ◽  
Takaomi Sanda ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Lines ◽  
Plasma Cell ◽  
Conflicts Of Interest ◽  
Cell Cancer ◽  
Ectopic Expression ◽  
Therapeutic Targets ◽  
Physical Interaction ◽  
Rna Seq ◽  
Normal Plasma

Background: Multiple myeloma (MM) is an aggressive neoplastic plasma cell cancer characterized by diversely cytogenetic abnormalities. MM can be divided into subtypes with immunoglobulin heavy chain (IGH) gene translocations involving CCND1-3, FGFR3/MMSET, MAFs and hyperdiploid myeloma containing trisomies of several odd numbered chromosomes 3, 5, 7, 9, 11, 15, 19, and 21. Although several new drugs have been introduced into clinic, treatment for MM patients remains challenge and refractory/resistant to therapy is often seen. Thus, a better understanding of the molecular pathogenesis of MM can lead to generate new prognostic classification and identify new therapeutic targets. Super-enhancers (SEs) are defined as large clusters of cis-acting enhancers, marked by high level bindings of acetylation of histone H3 lysine 27 (H3K27ac) and mediator complex. SEs have been shown to control genes for maintaining cellular identity and also key tumor drivers in various malignancies. Methods: H3K27Ac ChIP-seq and RNA-seq were performed on primary MM patient samples, MM cell lines. Normal plasma cells and lymphoma cell lines were served as controls. We systematically compared SEs and their associated genes of normal and cancerous tissue. THZ1, a CDK7 inhibitor, was used to efficiently down-regulate SE-associated genes. Combinatory analysis of THZ1-sensitive and SE-associated gene revealed a number of promising MM oncogenes. CRISPR/Cas9 technology and ectopic expression experiments in conjunction with cellular functional assays were performed to determine the effects of candidate SE-genes on MM cells. Circularized chromatin conformation capture followed by sequencing (4C-seq) was applied to explore the direct contact of SE and promoter. Results: SE analysis uncovered some cell lineage-specific transcription factors (TFs) and known oncogenes in MM. Several key TFs, including IRF4, PRDM1, MYC and XBP1, were identified in most MM samples, confirming the origin of MM cells. These data reinforce the concept that SE establishment is a key component of MM biology. The acquisition of SEs around oncogene drivers is widely observed during tumorigenesis. ST3GAL6 and ADM were two known oncogenic drivers in myeloma cells, which were associated with super-enhancers in all MM samples but not in normal plasma cell and lymphoma cells. We also found SE constituents for multiple subtype-specific key oncogenes such as CCND1 in t(11;14) cells, C-MAF in t(14;16) cells, and NSD2 and FGFR3 in t(4;14) cells. Furthermore, THZ1 showed prominent anti-neoplastic effect against MM cells. SE-associated genes were more sensitive to THZ1 compared with those genes associated with typical enhancers (TEs). By overlapping THZ1-sensitve gene with SE-associated genes, we identified a number of novel MM oncogenes, including MAGI2, EDEM3, HJURP, LAMP5, MBD1 and UCK2 as a potential druggable kinase. The expression level of MAGI2 and HJURP confers poor prognosis in several MM datasets. MAGI2 silencing in MM cells decreased cell proliferation and induced apoptosis. qRT-PCR and Western blot analysis confirmed the overexpression of HJURP in t(4;14) cells relative to non-t(4;14) MM cells. Furthermore, 4C-seq analysis revealed the physical interaction between HJURP-SE and promoter and THZ1 treatment diminished this interaction. Motif search at SE constituents revealed a highly significant enrichment of NSD2 recognition. Significant reduction of NSD2 binding at HJURP-SE region was observed in KMS11 infected with NSD2-specific shRNAs. Interestingly, blocking SE sites by CRISPR/Cas9i or silencing HJURP by shRNA led to decreased HJURP expression and cell apoptosis, whereas overexpression of this gene promoted cell growth. Taken together, our data demonstrated that HJURP is a novel SE-associated oncogene in t(4;14) MM. Conclusions: Our integrative approaches by combing H3K27Ac ChIP-seq, RNA-seq and THZ1-sensitive transcript defined the landscape of SE and identified SE-associated novel oncogenes, as well as lineage-specific TFs in MM. Furthermore, we also revealed subtype-specific SE-driving oncogenic program in MM. Taken together, these results not provide novel insight into the MM pathology, but also offer novel, potential therapeutic targets, such as MAGI2, and HJURP for the treatment of MM patients. Disclosures No relevant conflicts of interest to declare.

scholarly journals A Gain of Function Mutation in the NSD2 Histone Methyltransferase Drives Glucocorticoid Resistance Via Blocking Receptor Auto-Induction and BIM/Bmf Expression in ALL

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3758-3758
Author(s):  
Jianping Li ◽  
Catalina Troche ◽  
Julia Hlavka Zhang ◽  
Jonathan Shrimp ◽  
Jacob S. Roth ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Line ◽  
Cell Lines ◽  
Mutant Allele ◽  
Gene Editing ◽  
Conflicts Of Interest ◽  
Chemotherapeutic Agents ◽  
Rna Seq ◽  
Mesenchymal Transition ◽  
Pediatric All

Despite improvements in chemotherapy that have increased the 5-year survival rates of pediatric ALL to close to 90%, 15-20% of patients may relapse with a very poor prognosis. Pediatric ALL patients, particularly those in relapse can harbor a specific point mutation (E1099K) in NSD2 (nuclear receptor binding SET domain protein 2) gene, also known as MMSET or WHSC1, which encodes a histone methyl transferase specific for H3K36me2. To understand the biology of mutant NSD2, we used CRISPR-Cas9 gene editing to disrupt the NSD2E1099K mutant allele in B-ALL cell lines (RCH-ACV and SEM) and T-ALL cell line (RPMI-8402) or insert the E1099K mutation into the NSD2WT T-ALL cell line (CEM) and B-ALL cell line (697). Cell lines in which the NSD2E1099K mutant allele is present display increased global levels of H3K36me2 and decreased H3K27me3. NSD2E1099Kcells demonstrate enhanced cell growth, colony formation and migration. NSD2E1099K mutant cell lines assayed by RNA-Seq exhibit an aberrant gene signature, mostly representing gene activation, with activation of signaling pathways, genes implicated in the epithelial mesenchymal transition and prominent expression of neural genes not generally found in hematopoietic tissues. Accordingly, NSD2E1099K cell lines showed prominent tropism to the central neural system in xenografts. To understand why this NSD2 mutations are identified prominently in children who relapse early from therapy for ALL, we performed high-throughput screening in our isogenic cell lines with the National Center for Advancing Translation Science (NCATS) Pharmaceutical Collection and other annotated chemical libraries and found that NSD2E1099K cells are resistant to glucocorticoids (GC) but not to other chemotherapeutic agents used to treat ALL such as vincristine, doxorubicin, cyclophosphamide, methotrexate, and 6-mercaptopurine. Accordingly, patient-derived-xenograft ALL cells with NSD2E1099K mutation were resistant to GC treatment. Reversion of NSD2E1099K mutation to NSD2WT restored GC sensitivity to both B- and T-ALL cell lines, which was accompanied by cell cycle arrest in G1 and induced-apoptosis. Furthermore, knock-in of the NSD2E1099K mutation conferred GC resistance to ALL cell lines by triggering cell cycle progression, proliferation and anti-apoptotic processes. Mice with NSD2E1099K xenografts were completely resistant to GC treatment while treatment of mice injected with isogenic NSD2WT cells led to significant tumor reduction and survival benefit. To illustrate these biological phenotypes and understand the molecular mechanism of GC resistance driven by NSD2E1099Kmutation, we investigated the GC-induced transcriptome, GC receptor (GR) binding sites and related epigenetic changes in isogenic ALL cell lines in response to GC treatment. RNA-Seq showed that GC transcriptional response was almost completely blocked in NSD2E1099K cells, especially in T-ALL cell lines, correlating with their lack of biological response. GC treatment activated apoptotic pathways and downregulated cell cycle and DNA repair pathways only in NSD2WT cells. The critical pro-apoptotic regulators BIM and BMF failed to be activated by GC in NSD2E1099K cells but were prominently activated when the NSD2 mutation was removed. Chromatin immunoprecipitation sequencing (ChIP-Seq) showed that, the NSD2E1099K mutation blocked the ability of GR and CTCF to bind most GC response elements (GREs) such as those within BIM and BMF. While GR binding in NSD2WT cells was accompanied by increased H3K27 acetylation and gene expression, this failed to occur in NSD2 mutant cells. Furthermore, we found that GR RNA and protein levels were repressed in ALL cells expressing NSD2E1099K and GC failed to induce GR expression in these cells. Paradoxically, while H3K27me3 levels were generally decreased in NSD2E1099K cells, we saw increased levels of H3K27me3 at the GRE within the GR gene body where GR itself and CTCF normally bind, suggesting a novel role for the polycomb repressive complex 2 and EZH2 inhibitors for this form of GC resistance. In conclusion, these studies demonstrate that NSD2E1099K mutation may play an important role in treatment failure of pediatric ALL relapse by interfering with the GR expression and its ability to bind and activate key target genes. Gene editing screens are being performed to understand how to overcome this resistance. Disclosures No relevant conflicts of interest to declare.

Relationship of Area-Level Socioeconomic Status Indicators and Nutritional Anemias: Analysis of Folate, Vitamin B12, and Iron Deficiencies

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 16-17
Author(s):  
Miguel Gonzalez Velez ◽  
Carolyn Mead-Harvey ◽  
Heidi E. Kosiorek ◽  
Yael Kusne ◽  
Leyla Bojanini ◽  
...  
Keyword(s):  
Socioeconomic Status ◽  
Vitamin B12 ◽  
Conflicts Of Interest ◽  
Population Level ◽  
Serum Folate ◽  
Continuous Variables ◽  
Cross Sectional ◽  
The Us ◽  
Relationship Of ◽  
The Relationship

Introduction: Serum folate (SF), vitamin B12 (B12), and iron deficiency (def) are common causes of nutritional anemias (NA). These deficiencies are usually multifactorial, with nutritional and non-nutritional causes playing a role. SF, B12, and iron levels are usually ordered in the setting of anemia, and malnutrition with or without neurologic symptoms. Clinical evidence suggests that these def have a strong dietary component and socioeconomic status (SES). The relationship of NA and area-based SES in the US has not been studied. We aimed to determine the relationship of SES with the prevalence of NA. Methods: We performed a cross-sectional analysis of adult patients with SF, B12 and iron levels at Mayo Clinic Arizona and Florida between 2010 and 2018. Race was classified using the NIH criteria. Normal laboratory values were determined according to our lab reference and the US NHANES III. SF levels (mcg/Lt) were defined as deficient &lt;4, normal ≥4.0, and excess ≥20. B12 levels (ng/L) as deficient &lt;150, borderline 150-400, normal &gt;400-900, and excess ≥900. Iron def was determined by ferritin levels (mcg/L) as low &lt;24, normal 24-336, elevated &gt;336 for men, low &lt;11, normal 11-307, elevated &gt;307 for women. Area-Level SES indicators: Median Household income (MHI), unemployment rate (UR), median gross rent month (MGRM), % uninsured, median house value (MHV), % high school; were geocoded by zip code using the 2014 American Community Survey. Demographics and clinical variables were compared between groups by chi-square test for frequency data or Kruskal Wallis rank-sum test for continuous variables. Results: 202,046 samples from 128,084 patients were analyzed. In the sample-level analysis, there were statistically significant associations between SES and SF def; all SES indicators except UR for B12 def; and no differences for iron def, except % uninsured (Table 1). There was no statistically significant interaction between race and SES for SF def and iron def. Race was a statistically significant modifier between B12 def and MHI (p&lt;0.001), % uninsured (p=0.002), and MHV (p=0.007). Asian and Other race had an increase in odds of B12 def with increasing MHI (Asian OR=1.11 , Other OR=1.18); white race had a decrease in odds of B12 def with increasing MHI (OR=0.95 for a $10,000 increase in MHI). Conclusions: We show significant relationships between SES and NA in the US. Differences were observed between SF def and all the SES indicators without race interactions. There were significant interactions between B12 def, race and SES for pts of White, Asian and Other race. There were no differences between SES and race for iron def. These relationships confirm that NA are related to area-level SES and other social determinants of health. Research regarding the causes of these disparities on a population level are needed. Disclosures No relevant conflicts of interest to declare.

Magnetic nanoparticles for the measurement of cell mechanics using force-induced remnant magnetization spectroscopy

Nanoscale ◽  
2020 ◽  
Vol 12 (27) ◽  
pp. 14573-14580
Author(s):  
Min Xu ◽  
Xueyan Feng ◽  
Feng Feng ◽  
Hantao Pei ◽  
Ruping Liu ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cell Mechanics ◽  
Magnetic Nanoparticle ◽  
Adhesion Force ◽  
Force Spectroscopy ◽  
Remnant Magnetization ◽  
A Cell ◽  
Novel Method

Interactions of magnetic nanoparticles with cells were investigated from a cell mechanics perspective, and magnetic nanoparticle-based force spectroscopy was developed as a novel method to measure the adhesion force among various cancer cell lines.

scholarly journals Multicenter Study on Differential Human Neutrophil Antigen 2 Expression and Underlying Molecular Mechanisms

2020 ◽  
Vol 47 (5) ◽  
pp. 385-395
Author(s):  
Brigitte K. Flesch ◽  
Angelika Reil ◽  
Núria Nogués ◽  
Carme Canals ◽  
Peter Bugert ◽  
...  
Keyword(s):  
Expression Pattern ◽  
Human Neutrophil ◽  
Molecular Mechanisms ◽  
Normal Population ◽  
Regulatory Elements ◽  
Population Exposure ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Immune Neutropenia ◽  
The Impact

Background: The human neutrophil antigen 2 (HNA-2), which is expressed on CD177, is undetectable in 3–5% of the normal population. Exposure of these HNA-2null individuals to HNA-2-positive cells can cause immunization and pro­duction of HNA-2 antibodies, which can induce immune neutropenia and transfusion-related acute lung injury. In HNA-2-positive individuals, neutrophils are divided into a CD177pos. and a CD177neg. subpopulation. The molecular background of HNA-2 deficiency and the bimodal expression pattern, however, are not completely decoded. Study Design: An international collaboration was conducted on the genetic analysis of HNA-2-phenotyped blood samples, including HNA-2-deficient individuals, mothers, and the respective children with neonatal immune neutropenia and regular blood donors. Results: From a total of 54 HNA-2null individuals, 43 were homozygous for the CD177*787A>T substitution. Six carried the CD177*c.1291G>A single nucleotide polymorphism. All HNA-2-positive samples with >40% CD177pos. neutrophils carried the *787A wild-type allele, whereas a lower rate of CD177pos. neutrophils was preferentially associated with *c.787AT heterozygosity. Interestingly, only the *c.787A allele sequence was detected in complementary DNA (cDNA) sequence analysis carried out on all *c.787AT heterozygous individuals. However, cDNA analysis after sorting of CD177pos. and CD177neg. neutrophil subsets from HNA-2-positive individuals showed identical sequences, which makes regulatory elements within the promoter unlikely to affect CD177 gene transcription in different CD177 neutrophil subsets. Conclusion: This comprehensive study clearly demonstrates the impact of single nucleotide polymorphisms on the expression of HNA-2 on the neutrophil surface but challenges the hypothesis of regulatory epigenetic effects being implicated in the bimodal CD177 expression pattern.

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