Alpha‐1‐antitrypsin (A1AT) is an important inhibitor of neutrophil proteases including elastase, cathepsin G, and proteinase 3. Transcription profiling data suggest that A1AT is expressed by human ...neutrophil granulocytes during all developmental stages. A1AT has hitherto only been found associated with azurophile granules in neutrophils indicative of A1AT expression being restricted to the promyelocyte stage. We examined the localization and production of A1AT in healthy donor neutrophils and found A1AT to be a constituent of all granule subtypes and to be released from neutrophils following stimulation. A1AT is produced at all stages of myeloid maturation in the bone marrow. The production increases as neutrophils enter circulation and increases further upon migration to tissues as observed in skin windows and when blood neutrophils are incubated with granulocyte colony‐stimulating factor. Neutrophils from patients with A1AT‐deficiency carrying the (PI)ZZ mutation in the A1AT gene appeared structurally and functionally normal, but A1AT produced in leukocytes of these patients lacked the ability to bind proteases efficiently. We conclude that A1AT generation and release from neutrophils add significantly to the antiprotease levels in tissues during inflammation. Impaired binding of neutrophil A1AT to serine proteases in patients with (PI)ZZ mutations may enhance their susceptibility to the development of emphysema.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Specific granule protein of 28 kDa (SGP28), also termed cysteine-rich secretory protein 3 (CRISP-3), is a glycoprotein that belongs to a family of cysteine-rich secretory proteins (CRISPs). SGP28 was ...originally discovered in human neutrophils, but transcripts are widely distributed in exocrine glands (salivary glands, pancreas, and prostate) and also found at lower levels in epididymis, ovary, thymus, and colon. The function of SGP28/CRISP-3 is not yet known. Similarities to pathogenesis-related proteins in plants and the expression in neutrophils and exocrine glands suggest that SGP28/CRISP-3 may play a role in innate host defense. We describe here the production of a recombinant, C-terminally truncated form of CRISP-3 (rCRISP-3Δ) and the generation of polyclonal antibodies against rCRISP-3Δ that are useful in immunoblotting and immunocytochemistry. We present a specific, accurate, and reproducible enzyme-linked immunosorbant assay (ELISA) for the measurement of CRISP-3 with a detection limit of 2 ng/ml. We further demonstrate the presence of CRISP-3 protein in human plasma (6.3 μg/ml), saliva (21.8 μg/ml), seminal plasma (11.2 μg/ml), and sweat (0.15 μg/ml), and describe the coexistence of two different molecular weight forms of CRISP-3, representing an
N-glycosylated and a non-glycosylated form of the mature protein.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Neutrophil gelatinase-associated lipocalin (NGAL) is a 25-kDa lipocalin originally purified from human neutrophils. It exists in monomeric and homo- and heterodimeric forms, the latter as a dimer ...with human neutrophil gelatinase. It is secreted from specific granules of activated human neutrophils. Homologous proteins have been identified in mouse (24p3/uterocalin) and rat (α
2-microglobulin-related protein/neu-related lipocalin). Structural data have confirmed a typical lipocalin fold of NGAL with an eight-stranded β-barrel, but with an unusually large cavity lined with more polar and positively charged amino acid residues than normally seen in lipocalins. Chemotactic formyl-peptides from bacteria have been proposed as ligands of NGAL, but binding experiments and the structure of NGAL do not support this hypothesis. Besides neutrophils, NGAL is expressed in most tissues normally exposed to microorganisms, and its synthesis is induced in epithelial cells during inflammation. This may indicate either a microbicidal activity of NGAL or a role in regulation of inflammation or cellular growth, putative functions yet to be demonstrated.
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GEOZS, IJS, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
A 19 kDa protein was identified in specific granules of human neutrophils. A full-length cDNA clone was isolated from a human CML cDNA library, based on amino-acid sequences of isolated tryptic ...fragments. This clone includes the recently identified cDNA for FALL-39/CAP-18. Aminoacid sequences of proteolytic fragments derived both from the conserved N-terminal cathelin-like region and the highly variable C-terminal region characteristic of this family of bactericidal, LPS binding proteins, were in complete agreement with the sequence deduced from the cDNA. Thus, the 19 kDa protein is hCAP-18, stored as a ‘pro-peptide’ in specific granules.
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BFBNIB, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
: Neutrophil gelatinase‐associated lipocalin (NGAL) is a 25‐kDa protein initially isolated from the specific granules of human neutrophils. It is a member of the highly heterogeneous lipocalin ...protein family, which shares a common tertiary structure. Its synthesis is induced in gastrointestinal epithelium in association with inflammation and malignancy. To gain insight into its potential role in other epithelia we have investigated the expression of NGAL in human skin embryonic development, in normal adult skin, and in skin associated with inflammation and neoplastic transformation. In the present study we report that the embryonic expression of NGAL appears to be regulated in a spatio‐temporal pattern. It was induced in the interfollicular epidermis at 20–24 weeks of gestational age but thereafter progressively receded towards the hair follicles. In normal adult skin, NGAL was detected solely in association with hair follicles. However, strong induction of NGAL in the epidermis was seen in a variety of skin disorders characterized by dysregulated epithelial differentiation such as psoriasis, pityriasis rubra and squamous cell carcinoma. In these tissues production of NGAL was confined to spatially distinct subpopulations of keratinocytes underlying areas of parakeratosis, whereas skin samples lacking parakeratotic epithelium such as lichen ruber planus, acute contact eczema and basal cell carcinoma were negative for NGAL. Consistent with being a marker for disturbed terminal differentiation, NGAL immunoreactivity showed an inverse pattern when compared with that of the differentiation marker filaggrin. The biologic functions of NGAL in epithelia are not fully known, although an immunomodulatory role in host defense has been proposed. In addition, the transient interfollicular NGAL expression during skin embryogenesis along with the induction of NGAL in adult parakeratotic epidermis suggests it play a role in epithelial differentiation pathways.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Introduction
Clonal cytopenia of undetermined significance (CCUS) is a recently recognized hematological disorder characterized by the presence of one or more cytopenias, evidence of clonal ...hematopoiesis and not fulfilling the criteria for a myeloid neoplasm. In contrast to myelodysplastic syndromes (MDS) where 95% of the patients are anemic at time of diagnosis, that is only the case for around 60% of patients with CCUS (Weeks et al. Prediction of Risk for Myeloid Malignancy in Clonal Hematopoiesis. NEJM Evid. 2023). Furthermore, as recent studies on survival in CCUS primarily included younger patients (Weeks et al. NEJM Evid. 2023) or population-based cohorts not specifically referred for diagnostic work up of unexplained cytopenia (UC) (Rossi et al. Clinical relevance of clonal hematopoiesis in persons aged ≥80 years, Blood 2021) additional survival data on patients with CCUS are warranted. In this study, we investigated survival outcomes in patients with CCUS referred for primary work up of UC.
Methods
We included 241 patients with CCUS and compared them to 144 patients with low-risk MDS, defined as having less than 5% blasts in the bone marrow. Bone marrow biopsies and next-generation sequencing (NGS) were performed in all patients and cytogenetic analyses using G-band karyotyping was done in 362 (94%) of cases. For NGS, we used a gene panel with the most commonly mutated genes in MDS. The patients were included at 6 different institutions in Denmark from 2013 and onwards. A cut-point of 5 years follow-up was chosen for more robust survival data, and patients were censored at this time point if followed for more than 5 years. Patients with CCUS were stratified into 3 groups dependent on the type of cytopenia present at diagnosis. CCUS patients with pancytopenia (n = 35), and CCUS patients without pancytopenia were split based on whether they were anemic (n = 143) or not (n =63). We compared overall survival between the CCUS groups and low-risk MDS in a Cox proportional hazards model adjusted for age, sex, number of variants and presence of high-risk variants.
Results
Of the 241 CCUS patients, 178 (74%) were anemic (hemoglobin < 12 and 13 g/dL for women and men, respectively), while this was the case for 130 (90%) of the patients with MDS. A total of 772 variants were identified in the entire cohort with a median of 2 (IQR: 1-3) per patient for both CCUS and MDS patients. The overall survival at 5 years was 45% for low-risk MDS patients and 62% for CCUS patients. For CCUS patients without anemia, CCUS patients with anemia and CCUS patients with pancytopenia overall survival at 5 years was 85%, 52% and 55%, respectively (p < 0.0001). In the adjusted Cox proportional hazards model, we found a significantly superior overall survival for CCUS patients without anemia compared to those with anemia (HR: 0.28, 95%-CI: 0.13-0.58, p = 0.001) and pancytopenia (HR: 0.22, 95%-CI: 0.09-0.53, p = 0.001) and patients with low-risk MDS (HR: 0.18, 95%-CI: 0.09-0.38, p < 0.001). There was no significant survival difference between CCUS patients with pancytopenia and low-risk MDS patients (HR: 0.67, 95%-CI: 0.46-1.50, p = 0.5). Of the remaining variables, age was the strongest prognostic factor with hazard ratio increasing with a factor 1.05 (95%-CI: 1.03-1.07, p < 0.001) per year aged. Predicted survival probabilities for a 65-year-old and 80-year-old person demonstrate a substantial difference in overall survival across all 3 categories of CCUS (figure 1).
Discussion
Here we show that the presence of anemia impacts overall survival among CCUS patients. We observe that CCUS patients without anemia, representing 26% of CCUS patients in our cohort, have a superior overall survival compared to those with anemia, even with a comparable mutational profile. Our findings indicate that other factors than mutational signatures impact overall survival. Moreover, the prevalence of CCUS increases with age, and our findings demonstrate a considerable difference in survival between a 65-year-old and 80-year-old person diagnosed with CCUS. This raises the concern that prediction models can overestimate the survival rates if the elderly group of CCUS patients is not well represented in these models.
In conclusion, we show that age and hemoglobin levels are important factors in overall survival for CCUS patients, and that patients with CCUS without anemia have a superior overall survival and should be considered as a separate group within the CCUS category.
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IJS, IMTLJ, NUK, PNG, SAZU, UL, UM, UPUK, ZRSKP
The neutrophilic granulocyte is the most numerous leukocyte in peripheral blood. The development from a multipotent progenitor cell to a mature neutrophil takes place in the bone marrow over a period ...of 10–14 days. In order to understand the cellular mechanisms behind this process, it is necessary to investigate cells from different stages of neutrophil differentiation. As no human cell line has the ability to faithfully reproduce the entire differentiation process from promyelocyte to segmented neutrophil the analysis of many maturation-dependent processes has to be done on neutrophil precursors from human bone marrow. For this purpose, a technique whereby neutrophil precursors can be isolated from the bone marrow and separated according to their maturity is required. Two different methods have been shown to be useful for isolation of immature neutrophils: density centrifugation on a Percoll gradient, where the increasing density of the cells with maturity forms the basis of the separation, and multidimensional flow cytometry, where a combination of size, granulation, and surface markers are used for the discrimination of different neutrophil precursors. This paper will review these two methods for separation of neutrophil precursors with special emphasis on Percoll density centrifugation and the use of cells isolated by this technique for the analysis of neutrophil-specific mRNAs and the biosynthesis of neutrophil granule proteins.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
hCAP-18 is a newly described protein of human neutrophilic granulocytes which belongs to the cathelicidin family of antimicrobial proteins. Members of this protein family share a common N-terminal ...sequence followed by a highly diverse antimicrobial, cationic C-terminus. The present work describes the production of recombinant hCAP-18, the generation of antibodies to the protein and the development of an accurate, sensitive and specific ELISA for the detection of hCAP-18 in cells, plasma and urine with a detection limit of 0.084 ng/ml. The amount of hCAP-18 in neutrophils is 0.627
μg protein per 10
6 cells. The plasma level is 1.18
μg/ml which is several fold higher than for other neutrophil specific granule proteins. hCAP-18 is present in plasma as high molecular weight complexes. In accordance with this, hCAP-18 is barely excreted in the urine. The bone marrow appears to be the major source of plasma hCAP-18. The high level of hCAP-18 in plasma may provide an important defense against microorganisms and endotoxins.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The pathogenesis of chronic lymphocytic leukemia (CLL) is unknown but may involve aberrant activation of signaling pathways. Somatic hypermutations in rearranged immunoglobulin heavy-chain (IgVH) ...genes allow a division of CLL patients into 2 categories: mutated IgVH genes are associated with an indolent disease, whereas unmutated IgVH genes define an aggressive form. Using differential display to compare gene expression in CLL cells with and without IgVH hypermutations, we identified a novel gene, CLL up-regulated gene 1 (CLLU1), that was highly up-regulated in CLL cells without IgVH hypermutations. CLLU1 mapped to chromosome 12q22, within a cluster of genes that are active in germinal center B cells. However, appreciable levels of CLLU1 were detectable only in CLL cells and not in a panel of normal tissue extracts or in any other tested hematologic malignancy. High expression of CLLU1 in CLL samples occurred irrespective of trisomy 12 or large chromosomal rearrangements. CLLU1 encodes 6 mRNAs with no sequence homology to any known gene, and most transcripts appear to be noncoding. Two transcripts, however, potentially encode a peptide with remarkable structural similarity to human interleukin 4. These data, in particular the unique and restricted expression pattern, suggest that CLLU1 is the first disease-specific gene identified in CLL.
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IJS, IMTLJ, NUK, PNG, SAZU, UL, UM, UPUK, ZRSKP
Bactericidal/permeability‐increasing protein (BPI) neutralizes the proinflammatory effects of lipopolysaccharide and is of potential clinical use in the treatment of fulminant Gram‐negative ...infections. BPI is a cationic protein with antibacterial activity stored in azurophil (primary) granules of neutrophil granulocytes. However, the absence of BPI in patients with specific granule deficiency indicates a transcriptional control of BPI, which is distinct from that of other azurophil granule proteins. Accordingly, we demonstrate in vivo that the BPI mRNA level peaks, together with mRNA for specific granule proteins, during the myelocytic and metamyelocytic stage of granulocytic maturation. The human promyelocytic cell line NB4 expresses several azurophil granule proteins, but expression of BPI is undetectable. We show that treatment of NB4 cells with all‐trans retinoic acid (ATRA) induces BPI expression at mRNA and at protein level. The induction is dependent on de novo protein synthesis, as judged by sensitivity to cycloheximide. Previous investigations have indicated a potential role of CCAAT/enhancer‐binding protein (C/EBP) transcription factors in the regulation of BPI expression. Here, we show that induction of NB4 cells with ATRA correlates to direct binding of C/EBPβ and C/EBPε to the proximal BPI promoter, as determined by electrophoretic mobility shift analysis and chromatin immunoprecipitation. The dependency on C/EBPβ and C/EBPε provides an explanation for delayed BPI mRNA expression, as compared with mRNA of other azurophil granule proteins.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK