| 1. |
- Dadfar, Elham
(författare)
-
Leukocyte transmigration and gene expression in healthy subjects and patients with renal failure-application of the skin chamber technique
- 2006
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The migration of leukocytes from the peripheral circulation into infected or injured tissue is a fundamental step in the host-defense mechanism. The skin chamber technique is a well documented method for studies of leukocyte trans migration and function in vivo. Patients with chronic renal failure are highly susceptible to infections and one contributing factor is dysfunctional leukocytes. The aim of this thesis was to analyze the transmigration and state of activity in terms of adhesion molecule expression of in vivo transmigrated neutrophils and monocytes in healthy subjects and patients with renal failure, using the skin chamber technique. Results: We have shown that monocytes that have been newly recruited to sites of interstitial inflammation in vivo, prior to their differentiation to macrophages, have a preserved ability to respond to challenge with bacterial peptides in terms of CD11b upregulation and intracellular hydrogen peroxide production in healthy subjects. This indicates that newly recruited monocytes play an important role in the immediate response against invading pathogens. In order to study the immune response at the interstitial site in patients with renal failure, monocyte transmigration and state of activity in terms of CD11b expression was analysed in patients with moderate to severe renal failure, patients on peritoneal dialysis and healthy subjects. In addition to monocytes, we investigated granulocytes from patients on peritoneal dialysis. Transmigrated monocytes from patients with severe renal failure had a reduced ability to upregulate CD11b at the interstitial site of inflammation compared with cells collected from healthy subjects. The reduced CD11 b expression was more dependent on cellular factors than on the concentration of soluble mediators in the interstitial milieu. A reduced ability to upregulate CD11b was also observed in monocytes and neutrophils from patients on peritoneal dialysis. Since CD11 b plays a crucial role for innate immunity to invading microbes, these phenotypic aberrations may have pathophysiological consequences in terms of increased susceptibility to infectious diseases, a phenomenon observed in patients with renal failure. In order to understand the molecular mechanisms that contribute to the leukocyte dysfunction observed in patients with renal failure, gene expression profiling on peripheral and in vivo transmigrated neutrophils from patients with severe renal failure and healthy subjects was performed. Neutrophils from patients with renal failure showed a divergent gene expression pattern, compared to neutrophils from healthy subjects in the peripheral circulation and at the site of interstitial inflammation. The greatest differences were observed at the interstitial site. At that site, neutrophils from patients with renal failure had a higher gene expression of proinflammatory cytokines and cytokines involved in T-cell cell recruitment. In conclusion, a gradual loss of renal function is associated with impaired leukocyte CD11b expression at the interstitial site of inflammation. This is partly improved by renal replacement therapy. Furthermore, in vivo transmigrated neutrophils from patients with renal failure have a more pronounced expression of proinflammatory genes compared to healthy subjects. Our findings contributes to a better understanding of factors involved in the higher rate of infections observed in patients with renal failure. These data may generate potential platform for new therapeutic interventions.
|
|
| 2. |
- Lindberg, Jenny, et al.
(författare)
-
Monocyte and Neutrophil Chemotactic Activity at the Site of Interstitial Inflammation in Patients on High-Flux Hemodialysis or Hemodiafiltration
- 2009
-
Ingår i: Blood Purification. - : S. Karger AG. - 0253-5068 .- 1421-9735. ; 28:1, s. 47-52
-
Tidskriftsartikel (refereegranskat)abstract
- Background/Aims: We have observed a difference between patients on low-flux hemodialysis (HD) or peritoneal dialysis and patients on hemodiafiltration (HDF) or high-flux HD in the capacity of transmigrated leukocytes to mobilize CD11b in response to inflammatory stimuli compared with healthy subjects. This could be due to different interstitial chemokine concentrations. Methods: We measured concentrations of circulating and interstitial macrophage inflammatory protein-1 alpha (MIP-1 alpha), matrix metalloproteinase-9 (MMP-9)/neutrophil gelatinase-associated lipocalin (NGAL), monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) in 10 patients on HDF or high-flux HD and 11 healthy subjects by using immunoassay. Results: The interstitial concentrations of MIP-1 alpha, MMP-9/NGAL and IL-8 were similar in patients and healthy subjects, while the corresponding concentration of MCP-1 was significantly higher in patients on HDF or high-flux HD as compared with healthy subjects (p < 0.01). Conclusion: We suggest that an equal or higher concentration of chemokines in the interstitium in patients with HDF or high-flux HD might be one mechanism responsible for the preserved function of transmigrated leukocytes. Copyright (C) 2009 S. Karger AG, Basel
|
|
| 3. |
- Olsson, Jenny, et al.
(författare)
-
Expression of neutrophil SOD2 is reduced after lipopolysaccharide stimulation : A potential cause of neutrophil dysfunction in chronic kidney disease
- 2011
-
Ingår i: Nephrology Dialysis Transplantation. - : Oxford University Press (OUP). - 0931-0509 .- 1460-2385. ; 26:7, s. 2195-2201
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Neutrophils from patients with chronic kidney disease (CKD) are dysfunctional and thus a contributing factor to the risk of infections. The mechanisms for leucocyte dysfunction in CKD are not fully understood. It is known that lipopolysaccharide (LPS) activates transcription of several genes encoding proinflammatory cytokines. We therefore aimed to study the effect of LPS on neutrophil expression of genes related to the inflammatory response to address the hypothesis that LPS-induced gene transcriptions are altered in CKD patients.Methods. We analysed gene expression of LPS-stimulated neutrophils from 30 patients with CKD and 15 healthy controls. Superoxide dismutase-2 (SOD2), IL1A, IL-1R1, IL-1R2 and IL8RA gene expression from both neutrophils and differentiated HL60 cells were measured by quantitative polymerase chain reaction. Differentiated HL60 cells were stimulated with phorbol-12-myristate-7- acetate (PMA) after inhibition of SOD2 by small interfering RNA followed by respiratory burst assessment using flow cytometry.Results. LPS stimulation induced a significant mobilization of CD11b on neutrophils from CKD and healthy controls. Upregulation of SOD2, IL1A, IL-1R1 and IL-1R2 gene expression in neutrophils from healthy controls after LPS stimulation was contrasted by no change in gene transcription (IL-1R1 and IL-1R2) or even a downregulation in patients with CKD (SOD2 and IL1A). Inhibition of SOD2 reduced the PMA-induced respiratory burst and IL1A, IL-1R1, IL-1R2 and IL8RA gene expression in neutrophil-differentiated HL60 cells.Conclusions. Because of the critical role of SOD2 in the generation of hydrogen peroxide during phagocytosis, downregulation of SOD2 gene expression after LPS stimulation in neutrophils from patients with CKD indicates a potential mechanism for neutrophil dysfunction and cytokine dysregulation in these patients.
|
|
| 4. |
- Paulsson, Josefin, et al.
(författare)
-
Activation of peripheral and in vivo transmigrated neutrophils in patients with stable coronary artery disease
- 2007
-
Ingår i: Atherosclerosis. - : Elsevier BV. - 0021-9150 .- 1879-1484. ; 192:2, s. 328-334
-
Tidskriftsartikel (refereegranskat)abstract
- Accumulating evidence support a role of neutrophils in coronary artery disease (CAD). However little is known about the action of neutrophils at a local inflammatory site represented by an atherosclerotic plaque. To gain insight into these issues, we applied a skin blister model that permits analyses of in vivo transmigrated neutrophils. We hypothesised that the chronic inflammation in stable CAD mediates priming of neutrophils that impacts the out-come of neutrophil action at an inflammatory site. Thirteen patients with angiographically verified CAD were eligible for study entry together with 13 age and sex matched controls. Markers of inflammation (IL-6 and CRP), neutrophil activation (IL-8 and MMP-9/NGAL), and functional aspects (CD11b up-regulation and intracellular H(2)O(2) production) of peripheral and in vivo transmigrated neutrophils were studied. Systemic IL-8 and MMP-9/NGAL concentrations were significantly increased in patients indicating a primed state in circulating neutrophils. In vivo transmigrated neutrophils in stable CAD patients had an increased propensity to release MMP-9/NGAL and a reduced capacity to up-regulate CD11b and to produce hydrogen peroxide. These aberrations at the inflammatory site may be a consequence of a primed state of circulating neutrophils and point towards potential mechanisms whereby neutrophils at a local inflammatory site may contribute to the pathogenesis of CAD.
|
|
| 5. |
- Zagai, Ulrika, et al.
(författare)
-
Eosinophil Cationic Protein Stimulates TGF-β1 Release by Human Lung Fibroblasts In Vitro
- 2007
-
Ingår i: Inflammation. - : Springer Science and Business Media LLC. - 0360-3997 .- 1573-2576. ; 30:5, s. 153-160
-
Tidskriftsartikel (refereegranskat)abstract
- Eosinophilic inflammation and airway remodeling are features of asthma. Eosinophil cationic protein ( ECP) is released by activated eosinophils and transforming growth factor ( TGF)beta(1) has major functions in the fibrotic process. We therefore hypothesized that ECP stimulates TGF-beta(1) release by human lung fibroblasts. Fibroblasts in monolayer displayed a constitutive release of TGF-beta(1), which increased in presence of ECP ( 436 +/- 60 vs. 365 +/- 48 pg/ ml at 48 h; P< 0.01). mRNA expression of TGF-beta(1) was almost twofold in ECP- stimulated fibroblasts. ECP in threedimensional cultures stimulated both TGF-beta(1) release ( 180 +/- 61 vs. 137 +/- 54 pg/ ml; P< 0.01) and fibroblast- mediated collagen gel contraction ( 28 vs. 39% of initial gel area at 48 h; P< 0.001). ECP stimulates TGF-beta(1) release by human lung fibroblasts, suggesting a potential mechanism for eosinophils in the fibrotic response. This may be an important mechanism by which ECP promotes remodeling of extra cellular matrix leading to airway fibrosis in asthmatics.
|
|
