Biomedical subjects

C Sorg

Publications and source records attributed to C Sorg.

At least 91 records · Page 5Linked to original sources

PubMed1995

Immunohistochemical demonstration of the calcium-binding proteins MRP8 and MRP14 and their heterodimer (27E10 antigen) in Crohn's disease.

Monospecific antibodies against the calcium-binding proteins MRP8 and MRP14 and their heterodimer MRP8/14 (epitope 27E10) were used to investigate immunohistochemically the distribution of these proteins in routinely processed small and large bowel tissues from patients with Crohn's disease. MRP8, MRP14, and complex MRP8/14 were demonstrated in most granulocytes and macrophages in active Crohn's disease. Additionally, a strong complex MRP8/14 immunoreactivity was present in epithelial cells of the terminal ileum adjacent to ulcerative and fissuring lesions, whereas epithelial cells in large bowel tissues were consistently negative. Our results morphologically confirm the clinical finding of increased MRP8/14 serum levels in patients with active Crohn's disease; there is evidence that the serum MRP8/14 increase is caused by active secretion from granulocytes, monocytes, and epithelial cells.

Antibodies, Monoclonal↗

PubMed1995

Serum 27E10 antigen: a new potential marker for staging HIV disease.

MRP8 and MRP14 are myeloic related proteins expressed by most circulating and emigrated neutrophils and monocytes. Their composite molecule MRP8/14 (27E10 antigen) was shown to exhibit striking antimicrobial properties. The aim of the present study was to assess the value of MRPs as markers for detection of the different stages of HIV infection (Centres for Disease Control and Prevention, 1993). By employing the ELISA technique we measured serum concentrations of these proteins in samples from 122 HIV patients at the various stages of disease, and the results were compared with those for healthy controls. Serum levels of the heterodimeric molecule 27E10 were significantly increased (P < 0.001) in patients with CDC stages II and III, with the highest levels being in patients with stage III and acute ongoing opportunistic infections. For the single component MRP14, significantly raised levels (P < 0.05) were only found in HIV stage III individuals with acute clinical events. Similar associations were not found for MRP8 alone. Increase was not related to CD4+ cell count. There was a significant correlation between 27E10 antigen serum concentrations and levels of neopterin in patients with HIV stages II and III without acute concurrent illness. Patients being treated with Zidovudine showed no statistically significant variation in levels of 27E10 and its single components MRP8 and MRP14 compared with untreated patients. These findings suggest that elevation of MRP14 levels occurs in HIV+ individuals at later stages post-HIV infection, after the onset of opportunistic infections. 27E10 antigen is concluded to be a potential marker for the different stages of HIV disease.

AIDS-Related Opportunistic Infections↗

PubMed1995

The myeloic related protein MRP8/14 (27E10 antigen)--usefulness as a potential marker for disease activity in ulcerative colitis and putative biological function.

MRP8, MRP14 and their heterodimer MRP8/14 (27E10 antigen) are myeloic related proteins which have been shown to have a major role in inflammatory and immunological responses. In the present study monospecific antibodies against MRPs were used to investigate immunohistochemically the distribution of these proteins in routinely processed bowel tissues from 23 patients with ulcerative colitis (UC). MRP8, MRP14 and their heterocomplex MRP8/14 were demonstrated in the majority of granulocytes and macrophages in tissues of patients with active UC. Furthermore by employing the ELISA technique we measured MRP8/14 serum levels in 62 patients with UC and the results were compared with those for healthy controls. Disease activities were determined by established clinical activity indices. Serum MRP8/14 concentrations were significantly (P < 0.0001) increased in patients with active ulcerative colitis. No enhancement of serum levels were found for MRP14 and MRP8 alone, respectively. The follow-up of individual patients with initially active disease showed a decrease of MRP8/14 serum levels in parallel with clinical improvement following the start of therapy. It is thus concluded that MRP8/14 accurately reflects the degree of disease activity in UC. Further, possible biological function of MRPs seems to be associated with the heterodimeric form (27E10 antigen) rather than with individual proteins. Our morphological results confirm the finding of enhanced MRP8/14 serum levels in patients with active UC.

Adrenal Cortex Hormones↗

PubMed1995

Immunohistochemical distribution and serum levels of the Ca(2+)-binding proteins MRP8, MRP14 and their heterodimeric form MRP8/14 in Crohn's disease.

In previous histochemical studies the distribution of the two Ca(2+)-binding proteins MRP8 and MRP14 as well as their heterocomplex MRP8/14 has been demonstrated in different inflammatory diseases. Monoclonal antibodies against MRP8 and MRP14 and their heterodimer MRP8/14 (27E10 epitope) were used to investigate immunohistochemically the distribution of these proteins in routinely processed small and large bowel tissues from patients with Crohn's disease (CD). Furthermore, we used a sandwich immunoassay to measure serum concentrations of MRPs in 62 patients were simultaneously assessed by the Crohn's disease activity index (CDAI) and the severity activity index of Goebell (SAI). In our immunohistochemical study, MRP8, MRP14 and heterocomplex MRP8/14 were demonstrated in the majority of granulocytes and macrophages in active CD. Additionally, a strong complex MRP8/14 immunoreactivity was present in epithelial cells adjacent to ulcerative and fissuring lesions in the bowel. Serum MRP8/14 concentrations were significantly (p < 0.0001) increased in patients with active CD (CDAI > 150, SAI > 120). No correlations were found for level of MRP14 and MRP8 alone, respectively. The follow-up of individual patients with initially active CD showed a further increase in MRP8/14 levels during acute attacks of the inflammatory process. We suggest that our assay for MRP8/14 discriminates well between active and inactive CD and may have considerable potential in the analysis of clinical disease activity in CD patients. Our morphological results confirm the finding of increased MRP8/14 serum levels in patients with active CD.

Acute-Phase Proteins↗

PubMed1995

Monoclonal antibody 1F10 immunoreactivity in inflammatory bowel disease: a new marker specific only for continuous endothelial cells.

OBJECTIVE: To investigate in detail the immunohistochemical properties of the two endothelial-specific markers 1F10 (continuous endothelia) and MS-1 (discontinuous endothelia) in bowel tissues of patients suffering from chronic inflammatory bowel disease (IBD). METHOD: Immunohistochemical techniques were employed to study the morphology and phenotypic expression of these two proteins in routinely processed bowel tissues from 27 patients with Crohn's disease, 18 patients with ulcerative colitis, and 20 normal controls. RESULTS: All patients with IBD and controls showed a low to moderate 1F10 immunohistochemical staining restricted to the lamina propria and submucosa. In contrast to ulcerative colitis patients and healthy controls, 1F10 immunoreactivity was strongly upregulated in the muscularis propria of the small and large bowel in Crohn's disease patients regardless of the histological severity of the inflammatory process. We did not observe immunoreactivity for MS-1 on endothelial surfaces in either Crohn's disease or ulcerative colitis. CONCLUSIONS: We conclude that endothelia in patients with IBD do not undergo metaplasia. The high immunoreactivity of 1F10 antigen in the muscularis propria in Crohn's disease indicates a state of tropical immunological activation and may be important in the maintenance of chronic inflammation by facilitating leukocyte migration into sites of Crohn's disease involvement. Further studies of the factors controlling endothelial cell differentiation in the bowel of Crohn's disease patients may help to explain the features observed in this study.

Adolescent↗

PubMed1995

Expression of murine VCAM-1 in vitro and in different models of inflammation in vivo: correlation with immigration of monocytes.

VCAM-1 (vascular cell adhesion molecule-1) is a cytokine-inducible adhesion molecule which is known to mediate adhesion of mononuclear cells to endothelial cells in vitro via binding to the integrin VLA-4 (very late antigen-4). To further elucidate the role and regulation of VCAM-1 in vitro, we compared in vitro and in vivo expression of VCAM-1 in response to cytokines and investigated immunohistochemically the expression of VCAM-1 in three murine models of experimental inflammation. These models differed with regard to the pathogenetic mechanism, and the subsesquent infiltrate: allergic contact dermatitis (ACD) to DNFB as a T cell-controlled, DTH type of inflammation, cutaneous infection with Leishmania major as a chronic granulomatous inflammation and the cauterized cornea as a model for acute inflammation. VCAM-1 was found to be markedly enhanced on vascular endothelia in all types of inflammation and after subcutaneous administration of LPS and TNF-alpha. Administration of IL-4, however, failed to induce VCAM-1 both in vivo and in vitro. The increased VCAM-1 expression in the inflammatory models correlated with the appearance of infiltrating monocytes/macrophages. A concomitant influx of CD4-positive/CD8-positive lymphocytes was only observed in ACD and Leishmaniasis.

Animals↗

PubMed1994

Expression and complex formation of S100-like proteins MRP8 and MRP14 by macrophages during renal allograft rejection.

MRP8 and MRP14, two S100-like calcium-binding proteins, are expressed during differentiation of monocytes/macrophages. Both assemble to different noncovalently associated complexes that are supposed to represent the biologically active states. The present study was intended to investigate the molecular basis of macrophage heterogeneity with respect to expression and complex formation of MRP8 and MRP14 during acute and chronic rejection of renal allografts. First, specificity of antisera and mAbs to be directed against MRP8, MRP14, or MRP8/MRP14 heterodimers was determined by immunocytochemical and Western blot analyses of L132 fibroblasts (co-)transfected with MRP8 and/or MRP14 cDNA. Then, immunohistochemical analysis of biopsy specimens obtained from kidney allografts after acute rejection was performed, revealing a parallel expression of MRP8 and MRP14 with coincident MRP8/MRP14 heterodimer formation in infiltrating monocytes. In contrast, chronic allograft rejection was characterized by a subpopulation of monocytes defined by the absence of MRP8/MRP14 complex formation despite expression of MRP8 and MRP14 monomers. Double-labeling experiments showed that this was due in part to differential expression of MRP8 and MRP14 in infiltrate macrophages of chronic rejection. The data presented demonstrate for the first time differences in MRP8/MRP14 complex assembly by infiltrating monocytes in situ. These seem to be of pathophysiological relevance since complex formation defines subpopulations of monocytes associated with distinct pathways of immunological reactions. Differences in the mode of calcium-dependent signaling may, therefore, be of importance for understanding the molecular basis of macrophage heterogeneity during acute and chronic allograft rejection.

Adolescent↗

PubMed1994

Expression of the calcium-binding proteins MRP8 and MRP14 in monocytes is regulated by a calcium-induced suppressor mechanism.

MRP8 and MRP14 are two calcium-binding proteins of the S-100 family the expression of which is restricted to distinct stages of monocytic differentiation. Heteromeric MRP8/MRP14 complexes have been shown to represent their biologically active forms. However, it is not as yet clear whether biochemical modification of complexes, or regulation on the transcriptional level, are responsible for the control of MRP8/MRP14 expression. Employing Western-blot analysis and metabolic labelling we have demonstrated that patterns and metabolism of MRP8/MRP14 complexes do not change during up- or down-regulation of MRP8/MRP14. By Northern-blot analysis it was shown that MRP8/MRP14 are regulated at the transcriptional level rather than by biochemical modification of the complexes. Elevation of intracellular calcium levels by A23187, as well as by thapsigargin, was found to lead to specific down-regulation of MRP8/MRP14 mRNA which is in contrast with data reported for inflammatory factors such as interleukin-1 or tumour necrosis factor alpha. Concomitant application of actinomycin D and calcium ionophore indicated that this suppressive effect is mediated by decreased synthesis rather than increased degradation of MRP8/MRP14 mRNA. Finally, we demonstrated that calcium-mediated down-regulation of MRP8-MRP14 can be antagonized by cycloheximide, suggesting that a calcium-induced repressor protein is responsible for suppression of MRP8-MRP14 at the transcriptional level. Our data indicate that the function of MRP8-MRP14 is restricted to events associated with early stages of myelomonocytic activation.

Antigens, Differentiation↗

PubMed1994

The monoclonal antibody MAC387 detects an epitope on the calcium-binding protein MRP14.

The present study was initiated to identify the antigen recognized by the monoclonal antibody (MAb) MAC387 which is widely used for phenotypical characterization of myelomonocytic cells in situ. MAC387 has been described to show a similar reaction pattern as antisera to a complex formed by the calcium-binding proteins MRP8 and MRP14. However, the exact nature of the molecule recognized by MAC387 has been controversial. Using Western blot analysis, MAC387 was found to detect a single protein band of 14 kDa in lysates of human monocytes and granulocytes. Transfection of embryonic lung fibroblasts L132 with either MRP8 or MRP14 cDNA revealed that MAC387 reacts with MRP14 but not MRP8. This finding was confirmed by dot blot analysis of recombinant MRP8 and MRP14. Our data thus provide unequivocal evidence that MAC387 is a monoclonal antibody directed against the calcium-binding protein MRP14.

Animals↗

PubMed1994

Macrophages and angiogenesis.

Macrophages are supposed to play a key role in inflammatory and tumor angiogenesis. Their importance derives from (1) their ubiquitous presence in normal and especially inflamed tissues, (2) their potential to become activated in response to appropriate stimuli, and (3) their repertoire of secretory products. By release of proteases, growth factors (bFGF, GM-CSF, TGF-alpha, IGF-I, PDGF, VEGF/VPF, TGF-beta), and other monokines (IL-1, IL-6, IL-8, TNF-alpha, substance P, prostaglandins, interferons, thrombospondin 1), activated macrophages have the capability to influence each phase of the angiogenic process, such as alterations of the local extracellular matrix, induction of endothelial cells to migrate or proliferate, and inhibition of vascular growth with formation of differentiated capillaries. This review describes macrophage physiology and the influence of macrophage secretory products on the different phases of angiogenesis in vitro and in vivo.

Animals↗

PubMed1994

Ultrastructural localization of the S-100-like proteins MRP8 and MRP14 in monocytes is calcium-dependent.

MRP8 and MRP14 are members of the S-100 family of Ca(2+)-binding proteins and are expressed by granulocytes and monocytes. Members of this family have been described to be involved in membrane and cytoskeleton interactions; we therefore studied the subcellular distribution of MRP8/MRP14 in cultured human monocytes at the ultrastructural level. Monospecific rabbit antisera against MRP8 and MRP14 and a monoclonal antibody (moAb 27E10), which exclusively recognizes the MRP8/MRP14 heterodimer but not the monomers, were used in both immunoperoxidase/preembedding- and immunogold/cryotechniques. Comparing non-stimulated monocytes with Ca2+ ionophore A23187-treated cells, we could demonstrate that MRP8 and MRP14 associate with membrane and cytoskeletal structures in a Ca(2+)-dependent manner. Employing moAb 27E10, MRP8/MRP14 complexes were shown to be translocated to these cellular components. In addition, immunogold double-labelling experiments revealed a clear co-localization of MRP8/MRP14 complexes with the type III intermediate filament vimentin. Analysis of immunogold-labelled cryosections of renal allografts after acute vascular rejection demonstrated that a subpopulation of infiltrating macrophages showed a similar association of MRP8/MRP14 to the cytoskeleton in situ; this finding emphasizes the in vivo relevance of our observations. We conclude that Ca(2+)-dependent translocation of MRP8/MRP14 occurs to distinct subcellular components suggesting a role of these proteins for the modulation of cytoskeletal and membrane interactions.

Antigens, Differentiation↗

PubMed1994

Substance P and calcitonin gene-related peptide modulate leukocyte infiltration to mouse skin during allergic contact dermatitis.

The effects of the neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) on leukocyte infiltration during allergic contact dermatitis (ACD) in mice were studied. Concomitant topical application of SP or CGRP with the allergen oxazolone resulted in enhanced leukocyte recruitment at the sites of challenge. Immunohistochemical studies revealed that the numbers of T-helper (L3T4+) and cytotoxic (Lyt-2) lymphocytes and infiltrating macrophages (BM8+) were increased. In addition, ICAM-1 and MHC class II molecule expression by these cells was enhanced after neuropeptide application. Analysis by confocal laser scanning microscopy revealed an increase in the immunoreactivity for SP and CGRP in nerve fibres during the course of ACD. Flow cytometry studies showed that SP and CGRP did not upregulate expression of the adhesion molecules ICAM-1 and VCAM-1 by murine endothelial cell lines in vitro. This suggests that increased infiltration of leukocytes during ACD is not a consequence of direct neuropeptide-promoted upregulation of endothelial adhesion molecules in vivo. In conclusion, our observations provide evidence for a modulatory role of neuropeptides in the pathogenesis of ACD.

Animals↗

PubMed1994

Basal cells of the human epididymis--antigenic and ultrastructural similarities to tissue-fixed macrophages.

Very little is known about the basal cells in the epididymal epithelium. Their function is unclear, although they are present in all mammalian epididymides studied. The corpus epididymides from five patients undergoing castration because of prostatic carcinoma were fixed and processed for electron microscopy. Basal cells were characterized by a slightly heterochromatic nucleus with prominent nucleolus, pale round mitochondria, dispersed endoplasmic reticulum, and sparse Golgi apparatus; they were often rich in lipofuscin inclusions, possibly originating from principal cells. Some peritubular macrophages in close proximity to the epithelium were structurally similar to basal cells. Immunohistochemical staining revealed in the epididymides of another ten patients that the basal cells were recognized by the monoclonal antibody (mAb) 25F9 against mature, tissue-fixed macrophages but not by mAbs 27E10 or RM3/1, which were against activated macrophages usually found in acute or late inflammation, respectively. On the basis of the present findings, as a working hypothesis a scavenging role of the basal cells in a local immune defense mechanism is proposed, in which antigenic products (possibly of sperm degradation), taken up by the principal cells, would be phagocytosed by the basal cells. It could be inferred that when the basal cells are overloaded, they would leave the epithelium to be replenished by tissue-fixed macrophages.

Aged↗

PubMed1994

Differential regulation of the macrophage-specific surface antigen RM3/1 by cyclosporine, azathioprine, and dexamethasone.

CsA, AZA, and dexamethasone (DEX) were examined for their ability to modulate expression of surface antigens on human monocytes. Peripheral blood monocytes were cultured for 1 day, treated with various concentrations of immunosuppressants, and subsequently analyzed for expression of macrophage differentiation antigen RM3/1, intercellular adhesion molecule-1 (CD54), beta 2-integrin (CD18), and HLA-DR using flow cytometry and indirect immunofluorescence microscopy. The RM3/1 antigen was found to be significantly down-regulated by CsA and AZA in a dose-dependent manner, whereas DEX led to a marked up-regulation of the RM3/1 molecule. In contrast, expression of CD54, CD18, and HLA-DR by macrophages was not affected by treatment with these immunosuppressants. Effects of AZA, CsA, and DEX on RM3/1 surface expression were shown to be mediated via modulation of RM3/1 de novo synthesis. Immunohistochemical analysis of rejected renal allografts revealed that the RM3/1 antigen is expressed by the majority of infiltrating macrophages. Our data demonstrate that CsA, AZA, and DEX differentially affect gene expression, resulting in distinct macrophage phenotypes. Characterization of the RM3/1+ macrophage population in vitro and during the course of allograft rejection in vivo may thus provide further insights regarding the mode of immunosuppressant action on nonspecific effector mechanisms.

Anti-Inflammatory Agents, Non-Steroidal↗

PubMed1994

Expression of murine VCAM-1 in vitro and in different models of inflammation in vivo: correlation with immigration of monocytes.

VCAM-1 (vascular cell adhesion molecule-1) is a cytokine-inducible adhesion molecule which is known to mediate adhesion of mononuclear cells to endothelial cells in vitro via binding to the integrin VLA-4 (very late antigen-4). To further elucidate the role and regulation of VCAM-1 in vivo, we compared in vitro and in vivo expression of VCAM-1 in response to cytokines and investigated immunohistochemically the expression of VCAM-1 in three murine models of experimental inflammation. These models differed with regard to the pathogenetic mechanism and the subsequent infiltrate: allergic contact dermatitis (ACD) to DNFB as a T cell-controlled, DTH type of inflammation, cutaneous infection with Leishmania major as a chronic granulomatous inflammation and the cauterized cornea as a model for acute inflammation. VCAM-1 was found to be markedly enhanced on vascular endothelia in all types of inflammation and after subcutaneous administration of LPS and TNF-alpha. Administration of IL-4, however, failed to induce VCAM-1 both in vivo and in vitro. The increased VCAM-1 expression in the inflammatory models correlated with the appearance of infiltrating monocytes/macrophages. A concomitant influx of CD4-positive/CD8-positive lymphocytes was only observed in ACD and Leishmaniasis.

Animals↗

PubMed1993

Resistance of mice to experimental leishmaniasis is associated with more rapid appearance of mature macrophages in vitro and in vivo.

Resistance to murine leishmaniasis has been related to the propagation of specific Th cell subsets (Th1 and Th2). This study shows that there are differences between resistant and susceptible mice in the initial myelomonocytic infiltrate, which precede the specific T cell response. After subcutaneous injection of 2 x 10(7) Leishmania major into footpads of resistant C57Bl/6 and susceptible BALB/c mice we performed immunohistochemical studies on the infiltrate. Two days after infection the percentage of more mature, F4/80-positive macrophages in the lesion increased faster in C57Bl/6 mice (63%) than in BALB/c mice (29%). The same strain-specific differences were observed after infection of corresponding strains of athymic mice (57.2% in C57Bl/6 nu/nu; 33.6% in BALB/c nu/nu), thus excluding a T cell-controlled phenomenon. After 1 wk the infiltrate in susceptible mice began to reveal significantly more cells containing MRP14, which is expressed by granulocytes and less mature monocytes but not by mature macrophages. No corresponding differences were found between athymic strains, suggesting that at this point organization of the infiltrate falls under control of protective T cells. In bone marrow cultures of BALB/c and C57Bl/6 mice, the percentage of F4/80-positive macrophages was also increasing faster in C57Bl/6 mice than in BALB/c mice. Increased expression of the F4/80 Ag was associated with higher leishmanicidal activity of C57Bl/6 macrophages. MRP14-positive bone marrow cells on the other hand were rarely infected by parasites. We suggest 1) that the earlier appearance of leishmanicidal macrophages in lesions of C57Bl/6 mice could influence propagation of either Th1 or Th2 cells by reduction of parasite load or by differential secretion of decisive cytokines and 2) that the diffuse accumulation of granulocytes and inflammatory monocytes in susceptible mice facilitates spread of disease.

Animals↗

PubMed1993

MRP8 and MRP14, S-100-like proteins associated with myeloid differentiation, are translocated to plasma membrane and intermediate filaments in a calcium-dependent manner.

MRP8 and MRP14 are two Ca(2+)-binding proteins of the S-100 family expressed by myelomonocytic cells. Both proteins assemble to noncovalently associated complexes in a Ca(2+)-dependent manner. Members of the S-100 family are known to play a role in cytoskeletal-membrane interactions; therefore, we investigated the subcellular distribution of MRP8/MRP14 and their complexes in human monocytes. Using differential centrifugation and subsequent Western blot or enzyme-linked immunosorbent assay analysis, we found that MRP8/MRP14 were almost completely translocated from the cytoplasma to membrane and cytoskeletal structures in a Ca(2+)-dependent manner. Using a cross-linking technique, complexed forms of MRP8/MRP14 were found to be associated with the plasma membrane. Analysis of MRP-transfected L132 cells showed that the MRP8 as well as the MRP14 component of the MRP8/MRP14 complex may independently bind to membrane and cytoskeletal structures. Furthermore, immunogold electron microscopy showed a colocalization of MRP8/MRP14 and the intermediate filament type III protein vimentin in A23187-treated monocytes. Our data indicate that, in analogy to other S-100-like proteins, MRP8 and MRP14 play a role in Ca(2+)-dependent cytoskeletal-membrane interactions. Restriction of MRP8/MRP14 expression to distinct stages of myelomonocytic differentiation suggests that these proteins are involved in highly specific pathways of intracellular signaling in phagocytes.

Antibodies, Monoclonal↗

PubMed1993

Expression of calcium-binding proteins MRP8 and MRP14 is associated with distinct monocytic differentiation pathways in HL-60 cells.

MRP8 and MRP14 are two calcium-binding proteins of the S-100 family which are expressed during distinct stages of monocytic maturation. To further investigate their regulation the human leukemic cell line HL-60 which can be induced to differentiate to monocytes/macrophages by 12-O-tetradecanoylphorbol 13-acetate (TPA), 1,25-(OH)2 Vitamin D3 (VD3), tumor necrosis factor-alpha (TNF-alpha) and interferon-g (IFN-g) were analyzed for expression of MRP8/MRP14. Employing Northern blotting, a sandwich enzyme-linked immunosorbent assay and immunocytochemical analysis we determined MRP8/MRP14 mRNA and protein levels, which were found to be elevated after VD3 and reduced after TPA treatment. TNF-alpha and IFN-g did not affect MRP8/MRP14 levels. Western blot analysis revealed that formation of MRP8/MRP14 to biologically active complexes which has previously been shown to be a calcium-mediated process is not dependent on the differentiation stages of HL-60 cells. Restriction of MRP8/MRP14 expression to only distinct pathways of monocytic differentiation in HL-60 cells may thus reflect different functional phenotypes of monocytes/macrophages in vivo.

Calcium-Binding Proteins↗