Biomedical subjects

A Walz

Publications and source records attributed to A Walz.

At least 37 records · Page 2Linked to original sources

PubMed1997

LHRH receptors and LHRH receptor-bearing cells in pituitaries of streptozocin diabetic male rats.

Streptozocin (STZ)-diabetic rats have low hypothalamic luteotropic hormone-releasing hormone (LHRH) secretion and various alterations of gonadotrope cells, among which low luteotropic hormone (LH) secretion. Possible causes for the gonadotrope disorders may be low hypothalamic LHRH secretion alone or combined with reduced (a) number of LHRH receptor sites, or (b) receptor to ligand affinity, or (c) of LHRH receptor-bearing cells. To clarify this question we determined by saturation and competition binding Bmax, KD and KA of the LHRH receptor sites and counted the receptor-bearing cells in pituitary glands of control and STZ-diabetic adult male rats. We found a single receptor class, the Bmax was strongly reduced in diabetic animals whereas both KD and KA were similar in the two groups. The number of LHRH receptor-bearing cells in diabetic animals was increased. Therefore a reduced number of receptor sites per gonadotrope cell occurs in our model. Since in the STZ-diabetic male rats the number of gonadotropes is increased, a higher number of receptor-bearing cells was observed. We conclude that the reduced LH secretion from the diabetic pituitary gland might be due to a reduced number of LHRH receptor sites in the pituitary gland. The increased number of receptor-bearing cells might partially compensate for this change.

Animals↗

PubMed1997

The C-X-C chemokine ENA-78 is preferentially expressed in intestinal epithelium in inflammatory bowel disease.

BACKGROUND & AIMS: Secretion of chemokines by epithelial cells may represent a crucial event in the pathogenesis of inflammatory bowel disease (IBD). Expression of the chemokine epithelial neutrophil-activating peptide 78 (ENA-78) was monitored in patients with IBD and normal controls. METHODS: In situ hybridizations were performed on 41 tissue specimens from 15 patients with IBD and 10 controls to detect ENA-78 messenger RNA (mRNA). Immunofluorescence stainings were used to localize ENA-78 protein. RESULTS: Intestinal epithelial cells expressing ENA-78 mRNA at detectable levels are found at comparable frequencies in patients with Crohn's disease and ulcerative colitis. Tissue specimens with mild to moderate histological signs of disease activity show slightly higher frequencies of ENA-78 mRNA-expressing epithelial cells than areas with signs of severe disease activity (P = 0.14). Immunofluorescence stainings showed presence of the ENA-78 protein in > 90% of preserved epithelial cells in IBD, in control tissues, ENA-78 mRNA was not detectable, and ENA-78 protein was detectable in 0%-30% of epithelial cells. CONCLUSIONS: The observations are in agreement with a role of the C-X-C chemokine ENA-78 in the pathogenesis of IBD.

Acute Disease↗

PubMed1997

Excellent activity of newer quinolones on Legionella pneumophila in J774 macrophages.

The activity of six antibiotics directed against intracellularly multiplying Legionella pneumophilia was examined in tissue cultures with J774 macrophages. The drugs tested were the new quinolones, BAY Y 3118 and clinafloxacin, and ciprofloxacin, erythromycin, gentamicin and ampicillin served as reference drugs. Additionally, the MICs of these drugs against L. pneumophila were determined in vitro by broth microdilution. Despite their low MIC values, ampicillin and gentamicin did not inhibit intracellular multiplication of L. pneumophila in J774 macrophages. In contrast, an inhibition of intracellular growth could be demonstrated for the four other antibiotics. The new quinolones BAY Y 3118 and clinafloxacin showed the highest activity against intracellular L. pneumophila. At a concentration of 0.00078 mg/L already, a marked reduction in bacterial counts was seen for both drugs in comparison to the growth control without antibiotics. The corresponding effective concentrations were 0.0125 mg/L for ciprofloxacin and 0.2 mg/L for erythromycin. It may be concluded that new quinolone derivatives might become an alternative to erythromycin and rifampicin which at present are the drugs of primary choice for the treatment of legionnaires' disease.

Ampicillin↗

PubMed1997

Role of adherence in interleukin-8 induction in Helicobacter pylori-associated gastritis.

Active Helicobacter pylori-associated gastritis is characterized by a dense mucosal infiltration with granulocytes. Since H. pylori is noninvasive, secondary signals must induce the accumulation of granulocytes. Interleukin-8 (IL-8) has been shown to play a key role in this event. Using competitive reverse transcriptase-PCR on mRNA from gastric biopsies, we could show a clear correlation between the amount of IL-8 transcripts and the activity of H. pylori gastritis. Due to the inability of the bacterium to invade host cells, the epithelial layer is a potential candidate as an IL-8 source. To study the mechanism of IL-8 induction, established gastric carcinoma epithelial cell lines (AGS and Kato III) and well-defined H. pylori strains were used in a modified in vitro system. The experimental design enabled us to prevent direct contact of bacteria with epithelial cells by use of a filter membrane which did not block secreted bacterial products crossing the membrane. The data clearly showed that the direct contact of the bacterial cell with the epithelial cell is necessary for optimal IL-8 production because not only live bacteria, but also metabolically inactive bacteria, increased IL-8 secretion. Neither purified lipopolysaccharide nor water-soluble protein fractions of H. pylori NCTC 11637 and Tx30a nor the cytotoxin of H. pylori was able to increase IL-8 production significantly by the epithelial cells used. Furthermore, preparations of total membrane and outer membrane proteins of H. pylori were not able to stimulate IL-8 release in vitro. Accumulatively, these results imply that active metabolism is not necessary for stimulation as long as there is an intact membrane aiding the presentation of a stimulating membrane complex or aggregate on the surface of the bacteria. From these results, we conclude that whole bacteria and their direct contact with epithelial cells may be critical for IL-8 induction in vivo.

Bacterial Adhesion↗

PubMed1997

Essential role of heparan sulfates in axon navigation and targeting in the developing visual system.

Heparan sulfate (HS) is abundant in the developing brain and is a required co-factor for many types of fibroblast growth factor (FGF) signaling in vitro. We report that some HSs, when added exogenously to the developing Xenopus optic pathway, severely disrupt target recognition causing axons from the retina to bypass their primary target, the optic tectum. Significantly, HS sidechains from a neuroepithelial perlecan variant that preferentially bind FGF-2, HS(FGF-2), cause aberrant targeting, whereas those that preferentially bind FGF-1 do not. Charge-matched fragments of HS(FGF-2) show that the mistargeting activity associates with the FGF-binding fragments. Heparitinase removal of native HSs at the beginning of optic tract formation retards retinal axon elongation; addition of FGF-2 restores axon extension but axons lose directionality. Late HS removal, after axons have extended through the tract, elicits a tectal bypass phenotype indicating a growth promoting and guidance function for native HSs. Our results demonstrate that different HS sidechains from the same core protein differentially affect axon growth in vivo, possibly due to their distinct FGF-binding preferences, and suggest that growth factors and HSs are important partners in regulating axon growth and guidance in the developing visual system.

Animals↗

PubMed1996

The role of cytokine networks in the local liver injury following hepatic ischemia/reperfusion in the rat.

The liver is highly susceptible to a number of pathological insults, including ischemia/reperfusion injury. We have previously employed an animal model of hepatic ischemia/reperfusion injury, and have shown that this injury induces the production and release of hepatic-derived tumor necrosis factor alpha (TNF-alpha), which mediates, in part, local liver injury following hepatic reperfusion. In the present study, we have extended these previous observations to assess whether an interrelationship exists between TNF-alpha and the neutrophil chemoattractant/activating factor, epithelial neutrophil activating protein, that may account for some of the pathology of neutrophil-mediated ischemia/reperfusion-induced liver injury. We observed that hepatic ischemia/reperfusion injury leads to: (1) a coincident increase in hepatic neutrophil sequestration, elevated serum alanine aminotransferase (ALT) levels, and hepatic production of epithelial neutrophil activating protein; (2) passive immunization with neutralizing antibodies to TNF-alpha resulted in significant suppression of hepatic-derived epithelial neutrophil activating protein; and (3) neutralization of epithelial neutrophil activating protein by passive immunization significantly attenuated neutrophil sequestration in the liver and serum ALT levels. These findings support the notion that local expression of hepatic epithelial neutrophil activating protein produced in response to TNF-alpha is an important mediator of the local neutrophil-dependent hepatic injury associated with hepatic ischemia/reperfusion.

Alanine Transaminase↗

PubMed1996

Inflammatory cytokines in patients with persistence of the acute respiratory distress syndrome.

To determine the relationship between airspace cytokines and cellular inflammatory responses in patients with the acute respiratory distress syndrome (ARDS), we performed bronchoalveolar lavage (BAL) in 82 prospectively identified, mechanically ventilated patients on Days 3, 7, 14, and/or 21 after the onset of ARDS. We studied the relationships between bronchoalveolar lavage fluid (BALF) cell populations and the concentrations of two potent neutrophil (PMN) chemoattractants, interleukin-8 (IL-8) and epithelial cell-derived neutrophil activator-78 (ENA-78); two potent monocyte chemoattractants, monocyte chemotactic peptide-1 (MCP-1) and macrophage inflammatory peptide-1 alpha (MIP-1 alpha); and the early response cytokine interleukin-1 beta (IL-1 beta) and its naturally occurring antagonist, IL-1 receptor antagonist protein (IRAP). We found that all of these cytokines were significantly increased regardless of the duration of ARDS. IL-8 and ENA-78 were the cytokines most strongly and consistently correlated with PMN concentrations in the lung fluids of patients with ARDS, and the correlations were independent of the other cytokines or coexisting lung infection. None of the cytokines tested correlated with macrophage concentrations. MCP-1 was directly correlated with lung injury score on Days 7, 14, and 21. Although neither IL-8 nor ENA-78 was associated with outcome, levels of IL-1 beta measured on Day 7 were associated with an increased risk of death (odds ratio [OR] = 2.8; 95% confidence interval [CI] = 1.1 to 7.4). These data demonstrate potential molecular mechanisms of the persistent inflammatory process in the lungs of patients with ARDS.

Adolescent↗

PubMed1996

Kinetics of circulating adhesion molecules and chemokines after mechanical trauma and burns.

OBJECTIVE: To assess the role of circulating adhesion molecules and chemotactic cytokines within different settings of major trauma. DESIGN: Retrospective study. SETTING: Teaching hospitals, USA and Germany. SUBJECTS: Two groups of patients with multiple injuries (group I n = 155 and group II n = 12) with mean (SEM) injury severity scores (ISS) of 35 (4) and 32 (4) points, respectively, and 18 burned patients with a mean of ISS 38 (9) points. INTERVENTIONS: Serum samples were collected at the site of the accident and on admission to the (Group I) as well as during the post-trauma course in the hospital (Group II: days 1, 3, 5, 7, 10; Group III; weekly, up to week 10). MAIN OUTCOME MEASURES: Measurement of concentrations of soluble (s) adhesion molecules (sE-selectin, sP-selectin), and chemotactic cytokines (interleukin-8 [IL-8], epithelial cell derived neutrophil activating peptide 78 [ENA-78]) in serum after major mechanical trauma and burns. RESULTS: High concentrations of ENA-78 and sP-selectin were already present at the site of accident as well as one hour after injury. During recovery from the injuries, persistently high concentrations of IL-8, ENA-78, and sP-selectin were found, but sE-selectin was increased only during the first week after major trauma. CONCLUSION: Massive tissue trauma causes immediate activation of selected chemokines and adhesion molecules within minutes of the injury which will then persist depending on the type and severity of the injury for a substantial length of time. There was, however, no correlation between serum concentrations of the mediators investigated and susceptibility to complications or outcome.

Adolescent↗

PubMed1996

Thrombin-activated human platelets release two NAP-2 variants that stimulate polymorphonuclear leukocytes.

Thrombin-activated human platelets release substance(s) of a proteic nature which induce an increase in the intracellular calcium concentration in polymorphonuclear leukocytes (PMN). Aim of this study was to characterize the platelet released product(s) responsible for PMN stimulation. PMN-stimulating activity was isolated from platelet supernatant by FPLC and HPLC. The N-terminal sequence analysis revealed that the purified fractions consisted in 90% of a peptide of 73 amino acids and in 10% of a peptide of 74 amino acids; both are truncated forms of the connective tissue-activating peptide III (CTAP-III), a platelet alpha-granule product, and have 3 and 4 additional amino acids at the N-terminus compared with the neutrophil-activating peptide 2 (NAP-2): Asp-Leu-Tyr and Ser-Asp-Leu-Tyr, respectively. Treatment of platelet supernatant (previously depleted of PMN-activating nucleotides) with Affi-gel heparin resulted in the disappearance of PMN-stimulating effects, suggesting that NAP-2 variants, which are heparin-binding proteins, account for ATP-independent PMN-stimulating activity of the supernatant. Cross-desensitization between rNAP-2 and the platelet supernatant and inhibition by the anti-NAP-2 antibody are in agreement with this conclusion. Although NAP-2 and its variants are reportedly generated from the inactive precursors, CTAP-III and platelet basic protein, through a proteolytic cleavage, NAP-2 variants were not generated in our system by proteases deriving from platelets or contaminating leukocytes. Indeed, treatment of intact platelet suspensions with different protease inhibitors failed to modify the calcium stimulating activity of the resulting supernatants. In conclusion, thrombin-activated platelets release NAP-2 variants which are not generated outside the platelets by proteolytic processing but are released in an active form. This finding enhances our understanding of platelet-PMN interaction in thrombosis and inflammation.

Blood Coagulation Factors↗

PubMed1995

The functional role of the ELR motif in CXC chemokine-mediated angiogenesis.

In this study, we demonstrate that the CXC family of chemokines displays disparate angiogenic activity depending upon the presence or absence of the ELR motif. CXC chemokines containing the ELR motif (ELR-CXC chemokines) were found to be potent angiogenic factors, inducing both in vitro endothelial chemotaxis and in vivo corneal neovascularization. In contrast, the CXC chemokines lacking the ELR motif, platelet factor 4, interferon gamma-inducible protein 10, and monokine induced by gamma-interferon, not only failed to induce significant in vitro endothelial cell chemotaxis or in vivo corneal neovascularization but were found to be potent angiostatic factors in the presence of either ELR-CXC chemokines or the unrelated angiogenic factor, basic fibroblast growth factor. Additionally, mutant interleukin-8 proteins lacking the ELR motif demonstrated potent angiostatic effects in the presence of either ELR-CXC chemokines or basic fibroblast growth factor. In contrast, a mutant of monokine induced by gamma-interferon containing the ELR motif was found to induce in vivo angiogenic activity. These findings suggest a functional role of the ELR motif in determining the angiogenic or angiostatic potential of CXC chemokines, supporting the hypothesis that the net biological balance between angiogenic and angiostatic CXC chemokines may play an important role in regulating overall angiogenesis.

Amino Acid Sequence↗

PubMed1995

Epithelial-derived neutrophil-activating factor-78 production in human renal tubule epithelial cells and in renal allograft rejection.

Chemotactic cytokines, or chemokines, are likely mediators of inflammatory cell recruitment in renal allograft rejection. A recent addition to the C-X-C super gene family branch of chemokines is epithelial-derived neutrophil-activating factor-78 (ENA-78). ENA-78 is a 78-amino acid peptide with neutrophil-activating and chemotactic properties. This chemokine is unique in that it was originally isolated and cloned from an IL-1-stimulated human pulmonary epithelial cell line, A549. In this article, we investigated whether ENA-78 could be produced by human renal epithelial cells. We found that primary cultures of human renal cortical epithelial cells with tubular cell attributes could express significantly increased steady state levels of ENA-78 mRNA when stimulated with IL-1 beta (2.0 ng/ml). In addition, these cells also secreted significantly increased ENA-78 antigen compared with controls when stimulated with IL-1 beta (2.0 ng/ml). Other proinflammatory agonists, including TNF alpha, IFN gamma, and LPS failed to stimulate ENA-78 steady state mRNA or antigenic peptide production by renal cortical epithelial cells. In addition, biopsy tissue from acutely rejecting human renal allografts had higher copy number of ENA-78 mRNA compared with nonrejecting renal allograft controls using a quantitative reverse transcriptase polymerase chain reaction method with a mutant ENA-78 transcript. In the proinflammatory milieu of the rejecting renal allograft, IL-1 beta produced by host and donor mononuclear cells may drive ENA-78 production by allograft tubule cells, thus effecting leukocyte recruitment into the tubulointerstitial compartment.

Base Sequence↗

PubMed1995

Interleukin-13 effectively down-regulates the monocyte inflammatory potential during traumatic stress.

OBJECTIVES: To determine the potential of interleukin-13 (IL-13) to modify in vitro lipopolysaccharide-induced monocyte-macrophage (MO) activity in human cells from individuals who had sustained either major mechanical or burn injury and to investigate whether the effect of IL-13 is different on MOs that have been preactivated under traumatic stress than on monocytic cells from healthy volunteers. DESIGN: Peripheral MOs from 20 controls and 16 patients after major burn or mechanical trauma were separated on days 1, 3, 5, and 7 after injury and incubated with lipopolysaccharide (1 microgram/mL) in the presence or absence of IL-13 (10 ng/mL) for 4 hours and for 20 hours. Thereafter, the following measures were determined from the culture supernatants: neopterin, nitric oxide, tumor necrosis factor alpha, IL-1 beta, IL-6, and IL-8. RESULTS: Ex vivo lipopolysaccharide-activated MOs, compared with control cells, displayed considerably enhanced inflammatory activity during the immediate posttraumatic course, with a substantial and consistent elevation of levels of tumor necrosis factor alpha and IL-6. The addition of human recombinant IL-13 to the MO cultures resulted in an effective down-regulation of the synthesis of tumor necrosis factor alpha, IL-1 beta, and IL-6 as well as IL-8, showing an average reduction of mediator production to two thirds of the value found in corresponding sole lipopolysaccharide-stimulated cultures. The impact of human recombinant IL-13 on control MOs was almost identical for IL-6 and IL-1 beta, slightly lower for IL-8, and nonexistent for tumor necrosis factor alpha. CONCLUSION: From this study and preexisting findings, we conclude that, based on its biologic properties, IL-13 should be tested as a biologic response modifier for acute states of trauma-induced host defense deficiency.

Adult↗

PubMed1995

Role of C-X-C chemokines as regulators of angiogenesis in lung cancer.

Lung cancer is the leading cause of malignancy-related mortality in the U.S. and is predicted to increase over the remainder of this decade. Despite attempts to advance early diagnosis and use combination therapies, the clinical response of this cancer yields an overall 5-year survival rate of less than 15%. Clearly, new strategies for therapy are indicated. Although carcinogenesis is complex, tumor growth beyond 1-2 mm3 is dependent on angiogenesis. One of the potential mechanisms that allows for tumorigenesis is dysregulation of the balance of angiogenic and angiostatic factors that favors net neovascularization within the primary tumor. Numerous studies have investigated the role of a variety of molecules in the regulation of angiogenesis. Recently, interleukin-8 (IL-8), a member of the C-X-C chemokine family, has been found to be an angiogenic factor. In contrast, platelet factor 4 (PF4), another C-X-C chemokine, has been shown to have angiostatic properties. It is interesting that the major structural difference between IL-8 and PF4 is the presence of the NH2-terminal ELR (Glu-Leu-Arg) motif that precedes the first cysteine amino acid residue of IL-8 and is important in ligand/receptor interactions. We hypothesize that angiogenesis associated with tumorigenesis is dependent on members of the C-X-C chemokine family acting as either angiogenic or angiostatic factors. This paradigm predicts that the biological balance in the expression of these C-X-C chemokines dictates whether the neoplasm grows and develops metastatic potential or regresses. In this review we discuss our recent laboratory findings that support this contention and suggest that further elucidation of the biology of C-X-C chemokines in the context of neovascularization of nonsmall cell lung cancer will permit novel targeted therapy aimed specifically at attenuating tumor growth and metastasis.

Amino Acid Sequence↗

PubMed1995

Interferon-alpha and interferon-gamma down-regulate the production of interleukin-8 and ENA-78 in human monocytes.

The two chemotactic cytokines interleukin-8 (IL-8) and epithelial neutrophil activating protein 78 (ENA-78) were recently shown to be potent chemoattractants and activators of neutrophil function and to be present in certain inflammatory diseases. We have studied the effects of recombinant and natural interferon-alpha (IFN-alpha) and of recombinant interferon gamma (rIFN-gamma) on the production of IL-8 and ENA-78 in lipopolysaccharide- and interleukin-1-stimulated human monocytes. Both types of interferons showed a strong, concentration-dependent inhibition of neutrophil-stimulating bioactivity. Similarly, the secretion of IL-8 and ENA-78 was also inhibited by up to 73%. Northern blot experiments demonstrated that IFN-alpha decreases the steady-state levels of IL-8 and ENA-78 mRNA in monocytes, suggesting that IFN-alpha as well as IFN-gamma may control the expression of neutrophil chemotactic cytokines at the mRNA level.

Base Sequence↗

PubMed1995

Comparative analysis of transcription and protein release of the inflammatory cytokines interleukin-1 beta (IL-1 beta) and interleukin-8 (IL-8) following major burn and mechanical trauma.

The precondition for the systematic modulation of host impairing behavior of hyperactivated monocytes following trauma is to fully understand the mechanistic basis of cellular dysfunction. It was the objective of this study to scrutinize the synthesis patterns and the level of regulation of the functionally related inflammatory cytokines interleukin (IL)-1 beta and IL-8 under stressful conditions. We compared the quantity of cytokine protein release in lipopolysaccharide-stimulated in vitro cultures of peripheral blood mononuclear leukocytes with the signal intensity of the corresponding detectable mRNAs. Fourteen patients with major burn or multiple trauma on consecutive days post-trauma and healthy volunteers were studied. We saw an almost identical pattern of synthesis for both monokines during the time of observation, with a considerable impairment until day 5 post-trauma and recovery thereafter. In contrast to IL-1 beta, a clear concurrence between mRNA signal intensity and the quantity of protein release was found in the majority of patients for IL-8. From these data we conclude that the launching mechanisms for the de novo synthesis for both monokines under stress differ greatly, with IL-8 being clearly regulated on the transcriptional level, whereas the downregulation of IL-1 beta occurs, most likely, on the post-transcriptional level.

Adolescent↗

PubMed1995

Chemokine expression during hepatic ischemia/reperfusion-induced lung injury in the rat. The role of epithelial neutrophil activating protein.

The liver is highly susceptible to a number of pathological insults, including ischemia/reperfusion injury. One of the striking consequences of liver injury is the associated pulmonary dysfunction that may be related to the release of hepatic-derived cytokines. We have previously employed an animal model of hepatic ischemia/reperfusion injury, and demonstrated that this injury causes the production and release of hepatic-derived TNF, which mediates a neutrophil-dependent pulmonary microvascular injury. In this study, we have extended these previous observations to assess whether an interrelationship between TNF and the neutrophil chemoattractant/activating factor, epithelial neutrophil activating protein-78 (ENA-78), exists that may be accountable for the pathology of lung injury found in this model. In the context of hepatic ischemia/reperfusion injury, we demonstrated the following alterations in lung pathophysiology: (a) an increase in pulmonary microvascular permeability, lung neutrophil sequestration, and production of pulmonary-derived ENA-78; (b) passive immunization with neutralizing TNF antiserum resulted in a significant suppression of pulmonary-derived ENA-78; and (c) passive immunization with neutralizing ENA-78 antiserum resulted in a significant attenuation of pulmonary neutrophil sequestration and microvascular permeability similar to our previous studies with anti-TNF. These findings support the notion that pulmonary ENA-78 produced in response to hepatic-derived TNF is an important mediator of lung injury.

Animals↗

PubMed1995

Bovine melanoma growth stimulatory activity: a new monocyte-macrophage-derived cytokine of the IL-8 family. Partial structure, function, and expression in acute pulmonary inflammation.

BACKGROUND: Neutrophil-chemotactic peptides are a family of small basic peptides 70 to 80 amino acids in length. They contain four conserved cysteine residues, the first two spaced by one amino acid (C-X-C). The best characterized species is human IL-8. Other prominent members are melanoma growth stimulatory activity (GRO-alpha), neutrophil-activating peptide-2, and epithelial-cell derived neutrophil-activating protein 78. EXPERIMENTAL DESIGN: Bovine monocytes and alveolar macrophages were induced by lipopolysaccaride, and a major neutrophil chemotactic activity in the supernatant was purified by cation-exchange chromatography and reversed-phase HPLC. The chemotaxin was then analyzed for biologic activity on bovine neutrophils by in vitro chemotaxis, shape change, and transient rise of intracellular-free calcium concentration. The in vivo role of bovine GRO (boGRO) was tested immunohistologically in confirmed cases of pneumonic pasteurellosis. RESULTS: We have purified and partially sequenced a bovine homologue of human GRO-alpha. The partial amino acid sequence of boGRO was: APVVNELRCQCLQTLQGIHLKNIQSVKVTTPGP. BoGRO was biologically active and induced a dose-dependent neutrophil migration in the range of 10(-7) to 10(-9) M. BoGRO also induced a dose-dependent shape change in bovine neutrophils similar to human IL-8. This effect was detectable down to 10(-10) M. Similar effects were observed on the transient rise of intracellular-free calcium concentration. In bovine pneumonic pasteurellosis and, to a lesser extent, in normal lungs, immunoreactivity to human GRO was highly positive in hypertrophic type-II epithelial cells and in mesothelial cells, whereas pleural fibroblasts and bronchial epithelial cells were negative. CONCLUSIONS: BoGRO is a prominent neutrophil chemoattractant secreted by monocytes and alveolar macrophages. It is active at similar concentrations as human IL-8. The strong immunoreactivity in type-II epithelial and mesothelial cells of bovine pneumonia strongly suggest a role for boGRO in the genesis of pulmonary inflammation.

Acute Disease↗

PubMed1994

Characterization of the gene for human neutrophil-activating peptide 78 (ENA-78).

The genomic DNA for ENA-78 has been obtained from a human chromosome 4 flow-sorted cosmid library. Three out of 25,000 screened single colonies yielded the same 2.2-kB EcoRI ENA-78 gene fragment. A similar size fragment was observed on genomic southern blots, suggesting the presence of a single ENA-78 gene. The transcriptional start site was localized using a 5' RACE protocol on first strand cDNA prepared from stimulated alveolar type-II epithelial cell (A549) poly(A) mRNA. The ENA-78 gene contains four exons and three introns and the open reading frame of 342 nucleotides encodes for a protein of total 114 amino acids. The 5' flanking region contains potential binding sites for several nuclear factors such as AP-2, NF-kappa B, and interferon regulatory factor-1.

Amino Acid Sequence↗