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Kazuhiko Takehara

Publications and source records attributed to Kazuhiko Takehara.

At least 19 recordsLinked to original sources
PubMed2006

Both Th1 and Th2 chemokines are elevated in sera of patients with autoimmune blistering diseases.

Although chemokines are critical elements for the selective attraction and activation of various leukocyte subsets in the inflammatory process, there are few findings concerning T helper (Th) 1 or Th2 chemokines in autoimmune blistering disease (ABD). To determine whether serum levels of chemokines that are preferentially chemotactic for Th1 (monokine induced by IFN-gamma (MIG/CXCL9)) and Th2 (thymus and activation regulated chemokine (TARC/CCL17) and macrophage derived chemokine (MDC/CCL22)) cells were elevated and whether they correlated with the clinical features in patients with ABD. Serum chemokine levels were examined using ELISA in patients with pemphigus vulgaris (PV, n=19), pemphigus foliaceous (PF, n=14), or bullous pemphigoid (BP, n=27) and normal controls (n=20). Serum MIG levels were significantly higher in patients with PV, PF, or BP than those in the control subjects. Serum levels of TARC and MDC were also significantly elevated in patients with PV, PF, or BP relative to the normal controls. Among the ABD subgroups, the levels of each chemokine tended to be higher in BP patients than in PV patients. Furthermore, serum TARC levels correlated positively with serum IgE levels in patients with ABD. Levels of TARC, MDC, and MIG were significantly decreased after treatment when the skin lesions disappeared in these patients. Furthermore, serum MIG levels correlated positively with serum levels of TARC and MDC in the ABD patients. These results suggest that both a Th1 chemoattractant MIG and Th2 chemoattractants, TARC and MDC, cooperatively play a role in the development of ABD.

Adult↗
PubMed2006

L-selectin and intercellular adhesion molecule-1 regulate the development of Concanavalin A-induced liver injury.

Concanavalin A (Con A)-induced hepatitis is a model for human T cell-mediated hepatitis. We evaluated the role of L-selectin and intercellular adhesion molecule-1 (ICAM-1) in this model by injecting Con A intravenously in mice lacking L-selectin (L-selectin-/-), ICAM-1 (ICAM-1-/-), or both (L-selectin/ICAM-1-/-). Blood and liver samples were collected 0, 8, 24, and 48 h after Con A treatment. Increases in plasma transaminase levels, which peaked 8 h after injection, were reduced significantly in L-selectin-/-, ICAM-1-/-, and L-selectin/ICAM-1-/- mice compared with wild-type mice. Liver necrosis was more strongly inhibited in ICAM-1-/- mice than in L-selectin-/- mice but was most prominently reduced in L-selectin/ICAM-1-/- mice, in parallel with decreased plasma transaminase levels. The reduced severity of hepatitis in the mutant mice correlated with decreases in numbers of liver CD4+ T cells but not numbers of CD8+ T cells or neutrophils. Following Con A treatment, L-selectin deficiency reduced liver mRNA expression of tumor necrosis factor-alpha, and ICAM-1 deficiency reduced expression of interleukin-4. By contrast, reductions in liver macrophage inhibitor protein-1alpha mRNA occurred in all mutant mice. These results indicate that L-selectin and ICAM-1 contribute cooperatively to the development of Con A-induced hepatitis by regulating leukocyte infiltration and subsequent cytokine production.

Animals↗
PubMed2006

Elevated serum BAFF levels in patients with systemic sclerosis: enhanced BAFF signaling in systemic sclerosis B lymphocytes.

OBJECTIVE: To determine serum levels of BAFF, a potent B cell survival factor, in patients with systemic sclerosis (SSc) and relate the results to the clinical features of SSc. METHODS: Serum BAFF levels in 83 patients with SSc were examined by enzyme-linked immunosorbent assay (ELISA). In a longitudinal study, 131 serum samples obtained from 21 patients with SSc were analyzed. The expression of BAFF messenger RNA (mRNA) in the skin was quantified by real-time reverse transcription-polymerase chain reaction. The expression of BAFF receptor (BAFFR) on CD19+ B cells was assessed by flow cytometry. The production of IgG and interleukin-6 (IL-6) by isolated B cells was examined by ELISA. RESULTS: Serum BAFF levels were elevated in SSc patients compared with healthy controls and correlated positively with the extent of skin fibrosis. Among the 21 patients with SSc in the longitudinal study, 7 had decreased BAFF levels, 11 had levels that remained unchanged, and 3 patients had increased levels. Decreasing BAFF levels were accompanied by regression of skin sclerosis, whereas increasing levels of BAFF were associated with the new onset or worsening of organ involvement. BAFF mRNA expression was up-regulated in the affected skin of patients with early diffuse cutaneous SSc. BAFFR expression on B cells was increased in SSc patients relative to healthy controls. Furthermore, SSc B cells that were stimulated by BAFF exhibited an enhanced ability to produce IgG and IL-6. CONCLUSION: These results suggest that BAFF and its signaling in B cells contribute to B cell abnormalities and disease development in patients with SSc.

Adult↗
PubMed2006

Inhibitory role of CD19 in the progression of experimental autoimmune encephalomyelitis by regulating cytokine response.

Experimental autoimmune encephalomyelitis (EAE) is an inflammatory demyelinating disease of the central nerve system that is considered a T helper type 1 (Th1)-mediated autoimmune disease. EAE currently serves as an experimental animal model for multiple sclerosis in human. Cytokines, such as interferon-gamma and interleukin-10, play a key role in the development and remission of EAE. Recent studies have also shown a role for B cells in the pathogenesis of EAE. Therefore, we examined the role of CD19, a B cell-specific surface molecule that defines signaling thresholds critical for B-cell responses and autoimmunity, on the development of EAE. Following immunization with myelin oligodendrocyte glycoprotein (MOG) peptide, CD19-deficient (CD19(-/-)) mice exhibited higher clinical and pathological severity scores of EAE than wild-type mice. The increased severity of EAE in CD19(-/-) mice was associated with polarized Th1 cytokines in the inflamed central nerve system but not with anti-MOG antibodies in the serum. MOG-primed CD19(-/-) B cells produced high levels of interferon-gamma, and transfer of MOG-primed CD19(-/-) B cells to wild-type mice worsened the disease. Thus, CD19 modulates the Th1/Th2 cytokine balance in B cells and plays a critical role as a suppressive molecule in the development of EAE.

Adoptive Transfer↗
PubMed2006

Longitudinal analysis of serum cytokine concentrations in systemic sclerosis: association of interleukin 12 elevation with spontaneous regression of skin sclerosis.

OBJECTIVE: Skin sclerosis that progresses in the earlier disease phase in systemic sclerosis (SSc) spontaneously regresses thereafter. We investigated the relationship between changes of the serum cytokine profile and changes in skin fibrosis in patients with SSc. METHODS: Serum cytokine levels were examined by ELISA using 180 sera samples from 26 patients with early diffuse cutaneous SSc (dcSSc) with mean disease duration of 2.1 years. The mean followup period was 4.9 years (range 2-8). Cytokine mRNA expression in the affected skin was quantified by real-time reverse transcription-polymerase chain reaction. RESULTS: Modified Rodnan total skin thickness score decreased after 2, 4, and 6 years compared to that at first visit. Serum levels of the Th2 cytokines interleukin 6 (IL-6) and IL-10 and monocyte chemotactic protein-1 (MCP-1) were higher at first evaluation compared to healthy controls, while IL-4 levels were normal. Levels of all Th2 cytokines generally decreased as skin sclerosis regressed. Conversely, levels of serum IL-12, a Th1-inducing cytokine, were lower at first visit relative to controls, but increased by roughly 15-fold after 6 years to significantly higher levels than controls. Surviving dcSSc patients exhibited elevated IL-12 levels compared to deceased patients. Serum levels of transforming growth factor-ss1 (TGF-ss1), a fibrogenic cytokine, increased throughout followup, with slightly decreased levels at later timepoints. IL-12 mRNA expression was upregulated in affected skin from patients with late-stage dcSSc, while TGF-ss1 and MCP-1 expression was downregulated. CONCLUSION: These results suggest that a shift from Th2 to Th1 response correlates with improvement in skin fibrosis in SSc, and that IL-12 level is a serologically useful marker for disease activity and prognosis.

Adult↗
PubMed2005

Anti-DNA topoisomerase II alpha autoantibodies in Japanese patients with systemic sclerosis.

The pathogenesis and etiology of systemic sclerosis (SSc) remain unknown, but the presence of several autoantibodies is recognized as one of its prominent features. The clinical significance of anti-DNA topoisomerase II alpha antibody (anti-topo II alpha Ab) remains unknown in Japanese patients with SSc. To determine the prevalence and clinical correlation of anti-topo II alpha Ab in Japanese patients with SSc. Serum samples were obtained from 103 Japanese patients with SSc. Control serum samples were obtained from 43 healthy Japanese volunteers. Anti-topo II alpha Abs were determined by enzyme linked-immunosorbent assay.IgG anti-topo II alpha Ab levels were significantly increased in SSc patients (n=103) compared to normal controls (n=43; P<0.005). IgG or IgM anti-topo II alpha Ab was detected in 19% (20/103) of SSc patients when absorbance values higher than the mean+2SD of control serum samples were considered positive. By contrast, IgG or IgM anti-topo II alpha Ab was observed in only 7% (3/43) of healthy individuals. The presence of pulmonary fibrosis was more frequently detected in SSc patients with IgG anti-topo II alpha Ab than those without the Ab (P<0.05). Moreover, % DLco and % VC were significantly decreased in SSc patients with anti-topo II alpha Ab relative to those without the Ab (P<0.05 and P<0.01, respectively). The elevated levels of both erythrocyte sedimentation rate and C-reactive protein were also more frequently observed in SSc patients positive for IgG anti-topo II alpha Ab (P<0.005). The results of the present study indicate that anti-topo II alpha Ab represent one of the autoantibody specificities detected on SSc patients and may be regarded a serological marker of pulmonary fibrosis in Japanese patients with SSc.

Adult↗
PubMed2005

Clinical significance of serum levels of soluble intercellular adhesion molecule-1 and soluble L-selectin in malignant melanoma.

Although several molecules have been evaluated as tumor markers of malignant melanoma (MM) progression, there are few available markers sensitive enough to detect recurrence or metastasis. The objective of the present study was to determine clinical significance of serum soluble adhesion molecules in the monitoring of progression in patients with MM. Serum levels of soluble L-selectin (sL-selectin), sE-selectin, sP-selectin, and soluble intercellular adhesion molecule-1 (sICAM-1) were determined by ELISA in 57 MM patients. In a retrospective longitudinal study, nine serum samples from two MM patients were analyzed during a follow-up period of 4.0 and 4.3 years, respectively. Serum sICAM-1 levels in MM patients were significantly higher than those in healthy controls and tended to be elevated as the disease stage progressed. In contrast, serum sL-selectin levels were significantly lower in MM patients compared to healthy controls and tended to decrease as the disease stage progressed. There was no significant difference in serum sE-selectin and sP-selectin levels between MM patients and normal control. In a longitudinal study, increased sICAM-1 and decreased sL-selectin levels were generally associated with the progression of MM. These results suggest that monitoring both sICAM-1 and sL-selectin is available to evaluate the progression of MM.

Biomarkers, Tumor↗
PubMed2005

Successful treatment with sildenafil in systemic sclerosis patients with isolated pulmonary arterial hypertension: two case reports.

We describe two systemic sclerosis (SSc) patients with isolated pulmonary arterial hypertension (PAH) who were given treatment with 50 mg oral sildenafil per day. We evaluated the efficacy of oral sildenafil for isolated PAH in SSc patients by direct assessment with cardiac catheterization before and 6 months after the initiation of sildenafil. Right-heart catheterization demonstrated decreased mean pulmonary artery pressure, decreased pulmonary vascular resistance, and increased cardiac output after treatment with sildenafil. Brain natriuretic peptide levels were gradually decreased. The 6-min walking distance was greatly extended. Moreover, the physical conditions of both patients were much improved. We recognized no adverse events. We propose that oral sildenafil may be beneficial as a selective pulmonary vasodilator and as long-term treatment in SSc patients with isolated PAH.

Female↗
PubMed2005

Serum pulmonary and activation-regulated chemokine/CCL18 levels in patients with systemic sclerosis: a sensitive indicator of active pulmonary fibrosis.

OBJECTIVE: To clarify the clinical significance of serum levels of pulmonary and activation-regulated chemokine (PARC) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc) and to compare PARC levels with KL-6 antigen or surfactant protein D (SP-D) levels. METHODS: Serum PARC levels were determined by enzyme-linked immunosorbent assay in 123 SSc patients. In a retrospective longitudinal study, correlation of serum PARC levels with the activity of PF was assessed in 21 SSc patients with active PF. RESULTS: PARC levels at the first visit were higher in patients with SSc than in patients with systemic lupus erythematosus (SLE) or healthy controls. Increased serum PARC levels were associated with involvement of PF, decreased diffusing capacity for carbon monoxide, and decreased vital capacity in SSc patients. In the longitudinal study, serum PARC levels were significantly decreased in SSc patients with inactive PF compared with those with active PF. CONCLUSION: Elevated serum PARC levels correlated with PF and more sensitively reflected the PF activity than did serum KL-6 or SP-D levels in SSc. Serum PARC levels may be a useful new serum marker for active PF in SSc.

Antigens↗
PubMed2005

Connective tissue growth factor causes persistent proalpha2(I) collagen gene expression induced by transforming growth factor-beta in a mouse fibrosis model.

Skin fibrotic disorders such as systemic sclerosis (SSc) are characterized by an excessive production of extracellular matrix (ECM) and understood to develop under the influence of certain growth factors. Connective tissue growth factor (CTGF) is a cysteine-rich mitogenic peptide that is implicated in various fibrotic disorders and induced in fibroblasts after activation with transforming growth factor-beta (TGF-beta). To better understand the mechanisms of persistent fibrosis seen in SSc, we previously established an animal model of skin fibrosis induced by exogenous application of growth factors. In this model, TGF-beta transiently induced subcutaneous fibrosis and serial injections of CTGF after TGF-beta caused persistent fibrosis. To further define the mechanisms of skin fibrosis induced by TGF-beta and CTGF in vivo, we investigated in this study, the effects of growth factors on the promoter activity of the proalpha2 (I) collagen (COL1A2) gene in skin fibrosis. For this purpose, we utilized transgenic reporter mice harboring the -17 kb promoter sequence of the mouse COL1A2 linked to either a firefly luciferase gene or a bacterial beta-galactosidase gene. Serial injections of CTGF after TGF-beta resulted in a sustained elevation of COL1A2 mRNA expression and promoter activity compared with consecutive injection of TGF-beta alone on day 8. We also demonstrated that the number of fibroblasts with activated COL1A2 transcription was increased by serial injections of CTGF after TGF-beta in comparison with the injection of TGF-beta alone. Furthermore, the serial injections recruited mast cells and macrophages. The number of mast cells reached a maximum on day 4 and remained relatively high up to day 8. In contrast to the kinetics of mast cells, the number of macrophages was increased on day 4 and continued to rise during the subsequent consecutive CTGF injections until day 8. These results suggested that CTGF maintains TGF-beta-induced skin fibrosis by sustaining COL1A2 promoter activation and increasing the number of activated fibroblasts. The infiltrated mast cells and macrophages may also contribute to the maintenance of fibrosis.

Animals↗
PubMed2005

Pathogenesis of systemic sclerosis: altered B cell function is the key linking systemic autoimmunity and tissue fibrosis.

Systemic sclerosis (SSc) is characterized by autoimmunity and tissue fibrosis. There is a close association between specific autoantibodies and clinical features in patients with SSc. A number of studies have demonstrated that various cytokines, such as transforming growth factor-beta, modulate the synthesis of extracellular matrix by fibroblasts. However, it is not clear as to how autoimmunity and tissue fibrosis interact with each other. Recent studies have revealed that B cells play a critical role in various systemic autoimmune disorders. CD19 is a central regulator of B cell signaling threshold, and B cells from SSc patients exhibit an increased expression of CD19 that induces SSc-specific autoantibody production in transgenic mice. Furthermore, SSc patients have intrinsic B cell abnormalities characterized by decreased but activated memory B cells, which is possibly due to CD19 overexpression. Similarly, B cells from a tight-skin mouse, a model of SSc, show augmented CD19 signaling and chronic B cell activation. Remarkably, CD19 loss results in inhibition of chronic B cell hyper-reactivity and elimination of autoantibody production, which is associated with improvement in skin fibrosis and a parallel decrease in IL-6 production by B cells. Therefore, augmented cytokine production by B cells is a potential candidate for the induction of skin sclerosis. Alternatively, B cells may influence tissue fibrosis by regulating T cell activation and cytokine production through their antigen-presenting and co-stimulatory abilities. Thus, altered B cell function may result in tissue fibrosis, as well as autoimmunity, in SSc.

Animals↗
PubMed2005

Abnormal natural killer cell function in systemic sclerosis: altered cytokine production and defective killing activity.

Natural killer (NK) cells are innate immune effectors that produce various immunoregulatory cytokines. Recent studies have shown that NK cells are involved in the initiation of autoimmunity. In this study, we determined abnormalities of NK cells in systemic sclerosis (SSc), an autoimmune connective tissue disease, by assessing the frequency and absolute number, activation marker expression, cytokine production, and killing activity. The frequency and absolute number of NK cells increased in diffuse cutaneous SSc (dcSSc), whereas they were normal in limited cutaneous SSc (lcSSc). NK cells from both dcSSc and lcSSc patients exhibited activated phenotypes characterized by up-regulated CD16 and CD69 expression and downregulated CD62L expression. Interferon (IFN)-gamma production by non-stimulated NK cells from both dcSSc and lcSSc patients was increased compared to the normal control, whereas on stimulation, a reduced amount of IFN-gamma was produced. Interleukin (IL)-5 and IL-10 production by non-stimulated NK cells and IL-6 production by stimulated NK cells were augmented in dcSSc patients, but not in lcSSc patients. Despite the augmented cytokine production by non-stimulated NK cells, natural cytotoxicity activity and granzyme B secretion was reduced in NK cells from dcSSc and lcSSc patients. These results suggested that altered NK cell function contributes to immunological abnormalities in SSc.

Adult↗
PubMed2005

Quantification of human tissue kallikreins in the stratum corneum: dependence on age and gender.

Human tissue kallikreins are a family of 15 trypsin or chymotrypsin-like secreted serine proteases (hK1-hK15). hK5, hK6, hK7, hK8, and hK13 have been identified in the stratum corneum (SC), stratum granulosum, and skin appendages. It has been reported that hK5 and hK7 degrade desmosomes/corneodesmosomes, suggesting that kallikreins are responsible for desquamation. We report the quantification of hK5, hK6, hK7, hK8, hK10, hK11, hK13, and hK14 in the SC by ELISA and their variation among age groups. The total SC trypsin and chymotrypsin-like activities were also measured. The amount of hK7, hK8, and hK11 (ng per mg dry weight) were high, and varied from 6 to 14, hK5 (2.0-4.0) was present at intermediate levels, and hK10 (0.65-1.0), hK14 (0.1-0.3), hK6 (0.1-0.3), and hK13 (0.02-0.1) were present at lower levels. hK6 and hK14 were significantly lower in females between 20 and 59 y. hK5, hK7, hK10, hK11, and hK14 were not significantly different across the age groups. hK8 was lowest at extremes of age (highest at 30-39 y), hK6 was lower at >30 y, and hK13 was lower at >20 y. Overall trypsin-like activity did not differ across age groups but was higher in subjects <11 y. Overall chymotrypsin-like activity was not related to age. In conclusion, we found multiple kallikreins in the SC and suggest that these enzymes may be responsible for desquamation through an enzymatic cascade pathway.

Adolescent↗
PubMed2005

Molecular diagnosis of basal cell carcinoma and other basaloid cell neoplasms of the skin by the quantification of Gli1 transcript levels.

BACKGROUND: Distinguishing basal cell carcinoma (BCC) from other benign and malignant skin tumors is sometimes a difficult task for the pathologists. Because the activation of hedgehog signals and the up-regulation of its critical transcriptional factor Gli1 are well documented in BCC, a molecular technique measuring Gli1 transcripts may aide the diagnosis. METHODS: Gli1 transcript levels were measured by real-time quantitative reverse transcriptase polymerase chain reaction (RT-PCR) using RNA extracted from formalin-fixed, paraffin-embedded tissues of 68 cases of various skin tumors. Hematoxylin and eosin-stained pathology slides were independently reviewed by three expert dermatopathologists. RESULTS: The histological diagnoses were unambiguous in 53 tumors. The tumors included BCC (21), squamous cell carcinoma (13), seborrheic keratoses (8), trichoepithelioma (5), eccrine poroma/porocarcinoma (4), and sebaceous epithelioma/carcinoma (2). In these unambiguous cases, all BCC and trichoepithelioma tumors showed high expression of Gli1mRNA, while the expression was virtually absent in other tumors. The diagnosis was discordant among three pathologists in the remaining 15 tumors. Histological diagnoses included BCC, BCC with sebaceous differentiation, sebaceoma/sebaceous epithelioma, trichoblastoma, trichoepithelioma, basaloid follicular harmartoma, basosquamous carcinoma, etc. Six of them showed high Gli1 transcript levels. CONCLUSIONS: Quantification of Gli1 transcripts by RT-PCR is helpful in discriminating BCC and trichoepithelioma from other skin tumors.

Adult↗