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Knud Kragballe

Publications and source records attributed to Knud Kragballe.

18 recordsLinked to original sources
PubMed2006

Mitogen- and stress-activated protein kinase 1 is activated in lesional psoriatic epidermis and regulates the expression of pro-inflammatory cytokines.

Mitogen- and stress-activated protein kinase 1 (MSK1) is a downstream target of both the p38 and extracellular signal-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinases (MAPKs). MSK1 stimulates transcription of different pro-inflammatory genes through activation of transcription factors. The purpose of this study was to investigate the expression and activation of MSK1 in lesional psoriatic skin and its role in cytokine production in cultured normal human keratinocytes. Western blotting revealed a consistent and significant increase in phosphorylated (activated) MSK1(Ser376) in lesional psoriatic skin. Immunofluorescence staining revealed the phosphorylated MSK1(Thr581) to be localized in the basal layers of the epidermis in lesional psoriatic skin. No staining was found in non-lesional psoriatic skin. Cultured human keratinocytes incubated with anisomycin or IL-1beta resulted in the phosphorylation of the p38 MAPK and MSK1(Ser376). MSK1(Ser376) phosphorylation was inhibited by pre-incubation with the p38 inhibitor SB 202190. Transfection of the keratinocytes with specific MSK1 small interfering RNA resulted in 80% reduction of MSK1 expression and 51, 40, and 31% decrease in IL-6, IL-8, and tumor necrosis factor-alpha protein production, respectively. This study demonstrates for the first time the expression of MSK1 in epidermal keratinocytes and increased activation focally in psoriatic epidermis. As MSK1 regulates the production of pro-inflammatory cytokines, it may play a role in the pathogenesis of psoriasis.

Adult↗
PubMed2006

Protein expression of TNF-alpha in psoriatic skin is regulated at a posttranscriptional level by MAPK-activated protein kinase 2.

Alterations in specific signal transduction pathways may explain the increased expression of proinflammatory cytokines seen in inflammatory diseases such as psoriasis. We reveal increased TNF-alpha protein expression, but similar TNF-alpha mRNA levels, in lesional compared with nonlesional psoriatic skin, demonstrating for the first time that TNF-alpha expression in lesional psoriatic skin is regulated posttranscriptionally. Increased levels of activated MAPK-activated protein kinase 2 (MK2) together with increased MK2 kinase activity were found in lesional compared with nonlesional psoriatic skin. Immunohistochemical analysis showed that activated MK2 was located in the basal layers of the psoriatic epidermis, whereas no positive staining was seen in nonlesional psoriatic skin. In vitro experiments demonstrated that both anisomycin and IL-1beta caused a significant activation of p38 MAPK and MK2 in cultured normal human keratinocytes. In addition, TNF-alpha protein levels were significantly up-regulated in keratinocytes stimulated with anisomycin or IL-1beta. This increase in TNF-alpha protein expression was completely blocked by the p38 inhibitor, SB202190. Transfection of cultured keratinocytes with MK2-specific small interfering RNA led to a significant decrease in MK2 expression and a subsequent significant reduction in the protein expression of the proinflammatory cytokines TNF-alpha, IL-6, and IL-8, whereas no change in the expression of the anti-inflammatory cytokine IL-10 was seen. This is the first time that MK2 expression and activity have been investigated in an inflammatory disease such as psoriasis. The results strongly suggest that increased activation of MK2 is responsible for the elevated and posttranscriptionally regulated TNF-alpha protein expression in psoriatic skin, making MK2 a potential target in the treatment of psoriasis.

Adult↗
PubMed2006

Retrospective assessment of PASI 50 and PASI 75 attainment with a calcipotriol/betamethasone dipropionate ointment.

BACKGROUND: The US National Psoriasis Foundation recently recommended that PASI 50 and PASI 75 response rates be used in clinical trials to enable comparisons across studies of different psoriasis therapies. To date, these response rates have not been reported for the two-compound ointment containing calcipotriol and betamethasone dipropionate (Daivobet/Dovobet; LEO Pharma, Ballerup, Denmark). Further, in order to compare Daivobet with other therapeutics recently presented to the European regulatory authorities and the FDA, comparison with the biologicals, efalizumab, etanercept and alefacept, were also made. OBJECTIVES: To present the PASI 50 and PASI 75 results for the two-compound ointment containing calcipotriol and betamethasone dipropionate. METHODS: Data from six phase III studies conducted with the two-compound ointment were pooled and the PASI 50 and PASI 75 response rates calculated for patients with severe (PASI>or=17) or less severe disease (PASI<17) at treatment commencement. Results for the biological therapies, efalizumab, etanercept and alefacept, were obtained from relevant published phase III studies. RESULTS: PASI 50 and PASI 75 were achieved by more patients treated with the two-compound ointment than with the individual components. In patients with severe disease, the PASI 50 response rate after 4 weeks' treatment was 88.8% with the two-compound ointment, 69.2% with betamethasone dipropionate, 53.8% with calcipotriol, and 30.0% with ointment vehicle. In comparison, 12 weeks' treatment with the biologicals resulted in PASI 50 response rates of 59% with efalizumab, 74% with etanercept, and 56% with alefacept. CONCLUSIONS: The two-compound ointment is effective, producing a PASI 50 and PASI 75 response in greater than 80% and 50% of patients, respectively, regardless of psoriasis severity.

Alefacept↗
PubMed2005

KID Syndrome: report of a Scandinavian patient with connexin-26 gene mutation.

Keratitis-ichthyosis-deafness syndrome is a rare genodermatosis, which has recently been connected with mutations in the connexin-26 gene, GJB2. We present a 15-year-old boy with erythroderma, hyperkeratotic plaques and deafness. Sequencing analysis showed a heterozygous missense mutation D50N (148G>A) in GJB2. The boy has not yet manifested characteristic eye lesions but his case shows that tardy development of eye signs should not preclude a clinical diagnosis of keratitis-ichthyosis-deafness syndrome. Besides the typical clinical features, the patient's height was above the 98th percentile and he displayed a delayed bone age in his hands. Additionally, he suffered from migrainoid headaches and the results of a magnetic resonance scan of the cerebrum showed he had a large cisterna magna which probably occurred independently from the syndrome. This patient is the first Danish patient in whom the keratitis-ichthyosis-deafness syndrome has been verified by mutation analysis.

Adolescent↗
PubMed2005

Inverse regulation of the nuclear factor-kappaB binding to the p53 and interleukin-8 kappaB response elements in lesional psoriatic skin.

Nuclear factor-kappaB (NF-kappaB) is an inducible nuclear transcription factor regulating a range of cellular processes. An imbalance of the DNA binding activity of NF-kappaB may, therefore, be part of the pathophysiological mechanisms in psoriasis. The purpose of this study was to determine the NF-kappaB DNA binding activity in psoriatic skin using three different kappaB sites and to determine how DNA binding activity was modulated by the anti-psoriatic drug calcipotriol. By electrophoretic mobility shift assay, we demonstrated that the NF-kappaB DNA binding to the p53 kappaB site was decreased, whereas the NF-kappaB DNA binding to the interleukin-8 (IL-8) kappaB site was increased in lesional psoriatic skin compared with non-lesional psoriatic skin. No regulation was seen on the NF-kappaB DNA binding to the major histocompatibility complex class I kappaB site. These changes were paralleled by a similar decrease in p53 expression and an increase in IL-8 expression in involved psoriatic skin compared with uninvolved skin as determined by quantitative RT-PCR. The alteration in NF-kappaB DNA binding activity was neither accompanied by any change in the expression of the inhibitor kappaB (IkappaB) kinases, IKKalpha, IKKbeta, and IKKgamma nor in the expression of the NF-kappaB inhibitor proteins, IkappaBalpha and IkappaBbeta. Immunofluorescence analysis revealed that p65 was sequestered in the cytoplasm of keratinocytes, whereas p50 exhibited a cytoplasmic as well as a nuclear localization. Interestingly, this distribution of p50 and p65 was similar in lesional and non-lesional psoriatic skin. Topical application of calcipotriol to lesional psoriatic skin for 4 d resulted in increased NF-kappaB binding to the p53 kappaB site and decreased NF-kappaB binding to the IL-8 kappaB site. Taken together, our data demonstrate that the NF-kappaB DNA binding activity is regulated in a specific manner in psoriatic skin depending on the kappaB sites investigated, and that topical treatment of psoriatic skin normalizes the abnormal NF-kappaB binding activity seen in lesional psoriatic skin.

Administration, Cutaneous↗
PubMed2004

1alpha,25(OH)(2)D(3) regulates NF-kappaB DNA binding activity in cultured normal human keratinocytes through an increase in IkappaBalpha expression.

NF-kappaB is a dimeric transcription factor which regulates transcription of a number of different genes including IL-8 and p53. In resting cells NF-kappaB is usually retained in an inactive state in the cytoplasm through binding to a member of the inhibitory kappaB (IkappaB) protein family. The purpose of this study was to determine the effect of 1alpha,25(OH)(2)D(3) on NF-kappaB activation in both unstimulated and stimulated (IL-1alpha) cultured normal human keratinocytes. NF-kappaB DNA binding activity was determined by EMSA using two different oligonucleotides containing the kappaB sequence from either the IL-8 or the p53 promoter. IkappaBalpha and p53 expression was determined by Western blotting and IL-8 expression by ELISA. In unstimulated keratinocytes no NF-kappaB binding to the IL-8 kappaB binding sequence was detectable, whereas stimulation with IL-1alpha (10 ng/ml) led to a significant ( P<0.05) induction of NF-kappaB binding. In contrast NF-kappaB binding to the p53 kappaB binding sequence was detectable in unstimulated cells, although it was significantly increased after IL-1alpha (10 ng/ml) stimulation. Incubation with 1alpha,25(OH)(2)D(3) (10(-8)-10(-7) M) was shown to significantly ( P<0.05) stimulate the expression of IkappaBalpha and in parallel experiments with normal human keratinocytes stimulated with IL-1alpha (10 ng/ml) a significant ( P<0.05) time and dose-dependent decrease in NF-kappaB binding to the IL-8 kappaB binding sequence and in IL-8 expression were seen. A less-pronounced decrease in NF-kappaB binding to the p53 kappaB response element was seen after preincubation with 1alpha,25(OH)(2)D(3) and IL-1alpha stimulation, and it did not result in any change in p53 expression. These results demonstrate that 1alpha,25(OH)(2)D(3) inhibits NF-kappaB binding to the IL-8 kappaB binding sequence more potently than binding to the p53 kappaB binding sequence. We propose that this selectivity may be mediated through an increased expression of IkappaBalpha which leads to an inhibition of specific NF-kappaB subunits resulting in a selective regulation of NF-kappaB-induced gene transcription.

Adult↗
PubMed2004

Lysophosphatidylcholine induces keratinocyte differentiation and upregulation of AP-1- and NF-kappaB DNA-binding activity.

Lysophosphatidylcholine (lysoPC) is generated by the action of phospholipase A2 on membrane phosphatidylcholine, the most abundant cellular phospholipid. In vitro, lysoPC has pro-inflammatory properties, as it upregulates the expression of adhesion molecules and is a chemoattractant to monocytes and T lymphocytes. It upregulates the expression of a variety of genes including genes encoding growth factors and cyclooxygenase-2 and modulates other cellular responses like proliferation and differentiation. A role for lysoPC as an intracellular messenger transducing signals from membrane-associated receptors has also been suggested. However, the mechanisms behind the diverse actions of lysoPC are poorly understood. In this study we found that lysoPC in non-toxic concentrations caused increased activator protein-1 (AP-1) DNA-binding activity and transglutaminase-1 expression in cultured human keratinocytes. The effects on transglutaminase-1 and AP-1 were dependent on protein kinase C and mitogen-activated protein kinase kinase. In addition, lysoPC caused a rapid and transient increase in DNA-binding activity of nuclear factor-kappaB.

Cell Differentiation↗
PubMed2004

New vitamin D analogs in psoriasis.

Psoriasis is a common inflammatory and hyperproleferative skin disease characterized by infiltrated plaques of the skin and may involve nails, scalp and intertreginous areas. Recent years of research has shown that psoriasis can be treated topically with analogs of vitamin-D(3). Impaired differentiation and increased proliferation of epidermal keratinocytes are key features in psoriatic lesions together with a local activation of T lymphocytes. Evidence has accumulated that analogs of vitamin D(3) increase differentiation and inhibit proliferation of keratinocytes. Topical treatment with analogs of vitamin D(3) have in a number of trials shown improvement of psoriasis. Vitamin D analogs show the same efficacy as potent topical corticosteroids and do not produce skin atrophy during long-term therapy. Vitamin D analogs can be used both as monotherapy and in combination with topical corticosteroids, UVB, PUVA, acitretin, methotrexate and cyclosporine. The vitamin D(3) analog calcipotriol has been investigated in most detail and is available as an ointment, a cream and as a scalp solution. From clinical studies involving several thousands of patients, it can be concluded that calcipotriol is efficacious, safe and well-tolerated even on a long term basis.

Animals↗
PubMed2003

HuMax-CD4: a fully human monoclonal anti-CD4 antibody for the treatment of psoriasis vulgaris.

BACKGROUND: Psoriasis is characterized by infiltration with mononuclear cells. Especially activated memory CD4+ T cells are critical in the pathogenesis. Interaction between the CD4 receptor and the major histocompatibility complex class II molecule is important for T-cell activation. OBJECTIVE: To test safety and efficacy of a fully human monoclonal anti-CD4 antibody (HuMax-CD4) in the treatment of psoriasis. DESIGN: Multicenter, double-blind, placebo-controlled, randomized clinical trial. Patients Eighty-five patients with moderate to severe psoriasis. INTERVENTIONS: Subcutaneous infusions of placebo or HuMax-CD4 at doses of 20, 80, 160, or 280 mg once weekly for 4 weeks. MAIN OUTCOME MEASURES: Psoriasis Area and Severity Index (PASI), investigators' and patients' overall response assessment, adverse events, laboratory assessment including total T-cell and subtype counts, CD4 receptor occupancy, and interleukin 2 receptor levels. RESULTS: At week 7, mean PASI was reduced in all treatment groups (95% confidence intervals are in parentheses): placebo, 8% (-3% to 19%); 20 mg, 12% (-6% to 27%); 80 mg, 14% (-14% to 35%); 160 mg, 16% (-4% to 33%); and 280 mg, 24% (-10% to 48%). At the highest dose level, 6 (38%) of 16 patients obtained more than 25% reduction of PASI and 3 (19%) obtained more than 50% reduction of PASI. A dose-dependent decrease in total lymphocyte count was seen and was parallel to a dose-dependent decrease in CD4+ T cells. This decrease was due to a decrease in the memory subset, whereas the naive subset was affected to a minor degree. Four weeks of treatment with HuMax-CD4 was safe and well tolerated. CONCLUSIONS: Treatment with HuMax-CD4 led to a moderate, not statistically significant reduction in PASI. The efficacy results obtained after only 4 weeks of treatment suggest that longer treatment would lead to even further reduction of PASI.

Adult↗
PubMed2003

1alpha,25-dihydroxyvitamin D3 stimulates activator protein 1 DNA-binding activity by a phosphatidylinositol 3-kinase/Ras/MEK/extracellular signal regulated kinase 1/2 and c-Jun N-terminal kinase 1-dependent increase in c-Fos, Fra1, and c-Jun expression in human keratinocytes.

1alpha,25-Dihydroxyvitamin D3 added to human keratinocytes increases differentiation through an activation of the transcription factor activator protein 1. We have previously reported that the 1alpha,25-dihydroxyvitamin D3-induced increase of activator protein 1 DNA binding activity is mediated by a protein kinase C-independent mechanism. The purpose of this study was to investigate further the mechanisms by which 1alpha,25-dihydroxyvitamin D3 modulates activator protein 1 DNA binding activity in cultured normal human keratinocytes. Western blotting experiments revealed that 1alpha,25-dihydroxyvitamin D3 caused a rapid and transient activation of the mitogen-activated protein kinases, extracellular signal regulated kinase 1/2 and c-Jun N-terminal kinase 1. 1alpha,25-Dihydroxyvitamin D3 also enhanced the expression of the activator protein 1 subunits, c-Fos, Fra1, and c-Jun as determined by northern and western blotting. The 1alpha,25-dihydroxyvitamin D3-induced activator protein 1 DNA binding activity was completely blocked by the MEK inhibitor PD 98059 indicating that the MEK/extracellular signal regulated kinase pathway is involved in the activation of activator protein 1. Transfection experiments showed that 1alpha,25-dihydroxyvitamin D3 also increased the activator protein 1-dependent transactivation, which was completely blocked by expression of a dominant negative Ras, suggesting that the 1alpha,25-dihydroxyvitamin D3-induced activator protein 1 activity involves Ras-dependent signaling. Furthermore, preincubation of the keratinocytes with the specific phosphatidylinositol 3-kinase inhibitors, Wortmannin and LY294002, demonstrated that the 1alpha,25-dihydroxyvitamin D3-induced activation of extracellular signal regulated kinase 1/2 and c-Jun N-terminal kinase 1 required phosphatidylinositol 3-kinase activity. Finally, preincubation of keratinocytes with a polyclonal antibody against the membrane receptor annexin II, blocked the 1alpha,25-dihydroxyvitamin D3-induced activation of extracellular signal regulated kinase 1/2 and c-Jun N-terminal kinase 1. Taken together, our results indicate that 1alpha,25-dihydroxyvitamin D3, via binding to the membrane receptor annexin II, induces activation of the phos-phatidylinositol 3-kinase/Ras/MEK/extracellular signal regulated kinase 1/2 and c-Jun N-terminal kinase 1 signal transduction pathway resulting in increased expression of c-Fos, Fra1, and c-Jun, and subsequently increased activator protein 1 DNA binding activity and gene transcription.

Adult↗
PubMed2003

Expression and localization of peroxisome proliferator-activated receptors and nuclear factor kappaB in normal and lesional psoriatic skin.

Abnormal epidermal proliferation and differentiation characterize the inflammatory skin disease psoriasis. Here we demonstrate that expression of PPARdelta mRNA and protein is markedly upregulated in psoriatic lesions and that lipoxygenase products accumulating in psoriatic lesions are potent activators of PPARdelta. The expression levels of NF-kappaB p50 and p65 were not significantly altered in lesional compared with nonlesional psoriatic skin. In the basal layer of normal epidermis both p50 and p65 were sequestered in the cytoplasm, whereas p50, but not p65, localized to nuclei in the suprabasal layers, and this distribution was maintained in lesional psoriatic skin. In normal human keratinocytes PPAR agonists neither impaired IL-1beta-induced translocation of p65 nor IL-1beta-induced NF-kappaB DNA binding. We show that PPARdelta physically interacts with the N-terminal Rel homology domain of p65. Irrespective of the presence of agonists none of the PPAR subtypes decreased p65-mediated transactivation in keratinocytes. In contrast p65, but not p50, was a potent repressor of PPAR-mediated transactivation. The p65-dependent repression of PPARdelta- but not PPARalpha- or PPARgamma-mediated transactivation was partially relieved by forced expression of the coactivators p300 or CBP. We suggest that deficient NF-kappaB activation in chronic psoriatic plaques permitting unabated PPARdelta-mediated transactivation contributes to the pathologic phenotype of psoriasis.

CD36 Antigens↗
PubMed2003

Epidermal overexpression of interleukin-19 and -20 mRNA in psoriatic skin disappears after short-term treatment with cyclosporine a or calcipotriol.

Interleukin-19, 20, and 24 are new members of the IL-10 family binding and signaling through the IL-20R1/IL-20R2 heterodimer, while IL-20 and 24 also bind to the IL-20R2/IL-22R1 heterodimer. Using in situ hybridization we have studied mRNA expression of IL-19, 20, and 24 and their related receptor chains in skin from psoriatic patients before and during short-term treatment with either oral cyclosporine A or topical calcipotriol. In untreated lesions IL-19 and IL-20 mRNA was expressed focally in epidermis above the dermal papillae, whereas IL-24 was expressed in mononuclear cells in the dermal infiltrate. The expression of IL-19 and 20 mRNA was confined to the basal and suprabasal keratinocytes. No expression of IL-19 and 20 mRNA could be detected in uninvolved psoriatic skin. Treatment with cyclosporine A and calcipotriol resulted in disappearance of the IL-19 and 20 mRNA. Expression of mRNA for the receptor chains IL-20R1 and IL-20R2 was found throughout the psoriatic epidermal layer, whereas IL-22R1 mRNA was predominantly expressed in the superficial part of the psoriatic epidermis. These findings show that IL-19 and IL-20 are synthesized by a distinct population of keratinocytes. It remains to be clarified whether IL-19 and IL-20 are implicated in the pathogenesis of psoriasis.

Calcitriol↗
PubMed2002

Vitamin D and UVB radiation therapy.

Several studies have examined the combination of calcipotriene and UVB radiation in the treatment of psoriasis. Most show greater clearing with the combination than with monotherapy with either treatment. Data from one study found that calcipotriene had a UVB-sparing effect when combined with broadband UVB phototherapy, resulting in fewer UVB exposures and a lower cumulative dose. This finding suggests that patients treated with calcipotriene may be able to achieve lesion clearing with less frequent UVB radiation treatments than those not treated with calcipotriene. The combination of calcipotriene and UVB radiation does not alter the tolerability or safety of therapy. Calcipotriene may be applied at any time up to 2 hours before or immediately after UVB radiation.

Calcitriol↗
PubMedDate not supplied

Signal transduction pathways in human epidermis.

Cytokines, hormones and other signaling molecules regulate a number of diverse biological processes in the skin including the control of cell growth, differentiation, homeostasis, and various immune functions. This review describes the fundamental concepts of signaling in the cell and we discuss more thoroughly selected signaling pathways important in the skin. Fundamentally cellular signaling can be mediated through two different signaling mechanisms: 1) through binding to a receptor at the outer surface of the cellular-membrane and a subsequent activation of a signal transduction cascade. 2) through binding to nuclear receptors and subsequent regulation of gene-transcription. Changes in the signaling apparatus in the cell play a key role in the pathogenesis of a number of different skin diseases and a better understanding of these different signaling pathways may therefore offer new therapeutic targets.

Epidermis↗
PubMedDate not supplied

Psoriasis: severity assessment in clinical practice. Conclusions from workshop discussions and a prospective multicentre survey of psoriasis severity.

Psoriasis treatment is highly individualized. Although a standardized assessment of psoriasis severity for clinical practice may be theoretically advantageous for the purposes of determining treatment, the relevance of currently available research tools in clinical practice is uncertain. Our objectives were to ascertain in workshop discussions and through a prospective survey the relevance of standard severity measures in clinical practice with regard to choice of treatment. Although there was agreement on the possible structure of an algorithm for the treatment-related definition of psoriasis severity, consensus on the cut-off levels for the PASI and %BSA that would indicate a switch in treatment mode could not be reached. The lack of agreement prompted a prospective survey of 112 patients with psoriasis from 10 countries. This survey used a formal questionnaire asking for the PASI and %BSA scores, the patient's self assessment score (VAS ranging from 0 to 10), location of the psoriatic lesions and disease phase. Severity scores from 20 patients pre-selected for inclusion in a trial of a biological agent were included for comparison. Severity scores were analysed in relation to the choice of treatment (topical or systemic, which included phototherapy and combination) suggested by the treating physician.PASI scores differed significantly between the treatment groups (topical vs systemic, p=0.009); however, there was large overlap in the range of PASI scores between the groups. The same was true for VAS scores (topical vs systemic, p=0.035). %BSA scores were not significantly different between treatment groups. There was a large overlap for both the topical and systemic treatment groups with the biologicals group for the range of both the PASI and %BSA scores. A standardized protocol for the evaluation of psoriasis severity based on established severity scores (PASI, %BSA) appears to be unrealistic in day-to-day clinical practice. In clinical practice, a host of factors must be evaluated alongside possible metric measures. This requires experience and the specialized medical education of those involved in the treatment of patients with psoriasis.

Humans↗