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T Hirano

Publications and source records attributed to T Hirano.

At least 37 records · Page 2Linked to original sources
PubMed2004

Photodynamic therapy for malignant biliary obstruction: a case series.

We describe four elderly patients (age range 73-85 years) with bile duct carcinoma who were treated with photodynamic therapy. These patients could not be treated surgically because of the presence of cardiopulmonary disease and the extent of the bile duct carcinoma. Prior to photodynamic treatment the patients underwent percutaneous transhepatic biliary drainage (PTBD) to relieve jaundice. The photodynamic therapy was carried out under percutaneous transhepatic cholangioscopy, 2 days after intravenous administration of sodium porfimer (2 mg/kg). Excimer dye laser was used to irradiate the obstructive lesion with an energy dosage of 50 J/cm2 (total irradiation dose 150-250 J/cm2) and stenotic site with a dosage of 50-100 J/cm2. Photodynamic therapy was achieved safely without occurrence of cholangitis in all patients, and was followed by metallic stent placement, resulting in the improvement of performance levels in three patients who did not have liver metastases. Photodynamic therapy via the PTBD route is a safe and promising palliative therapy for selected elderly patients with bile duct carcinoma.

Aged↗
PubMed2004

Use of intraoperative dynamic infrared imaging with detection wavelength of 7-14 microm in the surgical obliteration of spinal arteriovenous fistula: case report and technical considerations.

BACKGROUND AND OBJECTIVE: Although improvements of spatial and temporal resolution in infrared (IR) imaging have enabled intraoperative real-time acquisition of physiological and pathological information on living organs, the imaging qualities of anatomical delineation of blood vessels and functional delineation of blood flow were insufficient to serve as visual monitoring. The main reason was partly due to the lack of an appropriate IR detection IR band (formerly 3 - 5 micro m), and the broad dynamic range in previous modalities. METHODS: To make a good contrast between blood vessels and surrounding tissues, the detection wavelength was shifted to the long-wave (7 - 14 micro m) part of IR spectrum, which includes the peak IR wave from living tissue (9 - 10 micro m), and the dynamic range was confined to +/- 10 degrees C around 35 degrees C. The novel camera system (IRIS IV infrared imaging system) was used for the visual monitoring of blood flow during the obliteration of a spinal perimedullary arteriovenous fistula at Th 7 in 71-year-old male patient. The temperature resolution of camera was 0.15 degrees C, with its intensity resolution of 16 bit (320 x 240 pixels), and data were stored at a rate of 30 frames/second. High-quality delineation of blood vessels and blood flow was obtained all through the procedure without use of cold saline, which was an inevitable procedure to make contrast in the previously used thermography. However, the occasional use of an air blower was helpful to achieve adequate images in the deep and narrow area of the surgical field. The amount of shunt flow reduction was visualized by the intensity in the acquired imaging, which was also confirmed later by digital subtraction angiography. CONCLUSION: From the present experience, it is considered that this type of imaging may be able to substitute intraoperative blood vessel and blood flow monitoring in spinal and other neurosurgical disorders.

Aged↗
PubMed2004

A case of plasmacytic hyperplasia arising in a kidney allograft salvaged with immunosuppression reduction alone.

Post-transplant lymphoproliferative disorder (PTLD) is a well-known complication of organ transplantation. Plasmacytic hyperplasia (PH) is thought of as the mildest form of PTLD; however, a graftectomy is necessary in most situations. We experienced an interesting case of PH arising in a kidney allograft, which could be relieved with a reduction in immunosuppression. A 27-year-old female underwent a living-related kidney transplantation. A 3-month non-episode protocol biopsy unexpectedly showed the devastating appearance of polymorphic plasma cell infiltration into the graft intersitium, compatible with PH. The PH was located in the graft by radiographic examinations. The infiltration of plasma cell disappeared completely on the 6-month graft biopsy specimen following immunosuppression reduction and the graft is functioning, although it was damaged by a subsequent acute rejection. Our present case indicates that some PTLD can be completely cured with a reduction in immunosuppression alone. The diagnostic modality for the evaluation of PTLD cell extinction is necessary to maintain graft function with adequate immunosuppression thereafter.

Adult↗
PubMed2004

Identification of the growth hormone receptor in an advanced teleost, the tilapia (Oreochromis mossambicus) with special reference to its distinct expression pattern in the ovary.

There is considerable evidence that the GH/IGF-I axis plays an important role in female reproduction. We report the isolation and characterization of the GH receptor (GH-R) and its gene expression profile during oogenesis in the tilapia, Oreochromis mossambicus. cDNA encoding GH-R was cloned and sequenced from the tilapia liver. The predicted GH-R preprotein consisted of 635 amino acids and contained a putative signal peptide, an extracellular region with a characteristic motif, a single transmembrane region, and a cytoplasmic region with conserved box 1 and 2 domains. The tilapia GH-R shared 34-74% identities with known GH-Rs in vertebrates. A binding assay using COS-7 cells showed that the cloned GH-R bound specifically to tilapia GH. Northern blot analysis showed a single mRNA transcript in the liver and ovary. In situ hybridization revealed intense signals of GH-R in the cytoplasm and nucleus of immature oocytes. The granulosa and theca cells surrounding vitellogenic oocytes also contained the GH-R mRNA signals. About a tenfold greater level of GH-R mRNA was found in the immature oocytes versus the mature oocytes, along with high levels of IGF-I mRNA. There were no significant changes in mRNA levels of GH-R and IGF-I in the liver or in plasma IGF-I levels during oocyte development. No correlation was found between hepatic GH-R mRNA and ovarian GH-R mRNA. These results suggest that the GH/IGF-I axis in the ovary may be involved in the early phases of oogenesis, under a different regulatory mechanism of GH-R gene expression from that of the liver.

Animals↗
PubMed2004

[Induction chemotherapy and radical resection for primary nonseminomatous mediastinal germ cell tumor (NSGCT); report of a case].

A 15-year-old male was admitted to our hospital for treatment of an anterior mediastinal tumor. The tumor was visualized by chest radiography 3 months prior to admission. Computed tomography (CT) revealed a heterogeneous solid tumor located in the anterior mediastinum. Although CT-guided needle biopsy had been performed twice, histologic diagnosis could not be confirmed. We believed this tumor to be nonseminomatous mediastinal germ cell tumor (NSGCT) and started intensive chemotherapy with cisplatin (CDDP) without histologic diagnosis because his serum AFP level was rapidly increasing. After 2 courses of chemotherapy, his serum AFP level returned to the normal range and surgical resection of the tumor with part of right lung was performed. Histopathological examination revealed that the tumor consisted of mature teratoma and yolk sac tumor. He underwent 1 course of chemotherapy post-operatively because a small number of viable cells were histopathologically recognized in the yolk sac component. At the time of writing, the patient is alive without any evidence of recurrence.

Adolescent↗
PubMed2004

[Bronchioloalveolar carcinoma illustrating difficulties in diagnosis and determination of operative management; report of a case].

A 56-year-old male was admitted to our hospital to treat for an abnormal lung shadow. Computed tomography (CT) revealed the shadow with ground-glass opacity that was 30 mm in diameter at left S6 lesion. Although transbronchial lung biopsy had been performed, histological diagnosis could not be made. We had expected the tumor could not be resected completely with a partial lung resection. Additionally, he refused being done a lower lobectomy without a histological diagnosis. So we performed a S6+S* segmentectomy with No. 7-12 lymph node dissection. Although the intraoperative frozen section diagnosis was an atypical adenomatous hyperplasia, the tumor was finally diagnosed as bronchioloalveolar carcinoma (BAC) because of its nuclear atypia. We did not resect the residual part of left lower lobe because he refused the additional operation and might have histopathologically no residual tumor and lymph node metastasis. At present, he is alive without any evidence of recurrence.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed2004

Outcomes of kidney transplants from non-heart-beating deceased donors as reported to the Japan Organ Transplant Network from April 1995-December 2003: a multi-center report.

Between April 1995-December 2003, 1,324 deceased donor kidney transplantations were performed in 139 transplant institutes in Japan. Of these, 45 transplants were from heart-beating and 1,279 transplants were from non-heart-beating deceased donors (NHBDD). Clinical outcomes for the 1,279 recipients of NHBDD kidney transplants were investigated. The overall 5-year patient and graft survival rates were 90% and 72%, respectively. A total of 112 NHBDD kidney grafts never functioned after transplantation and the recipients had to remain on dialysis. The causes of nonfunction were rejection, primary nonfunction, death, thrombosis and others in the order of the incidence. The major causes of graft loss were nonfunction, death, chronic rejection and acute rejection in that order. Major causes of recipient deaths were pneumonia, sepsis and CVA within 12 months, and heart diseases, sepsis, malignancy and pneumonia more than 12 months after transplantation. Kidneys from female donors, donors aged 15 or less or over age 60, donors with extrinsic causes of death other than head trauma, recipients over age 60 and those with diabetic nephropathy as their original disease were found to be at risk for poor graft survival. The lowest and last donor serum creatinine level did not influence the incidence of nonfunction or graft survival. However, graft survival was significantly poorer among recipients of older "expanded" donor kidneys than for recipients of younger grafts. The warm and total ischemia times should be kept shorter than 30 minutes (better 15 minutes), and 12 hours, respectively to minimize the incidence of nonfunction and early graft loss. It is especially important in cases with WIT over 30 minutes that the total ischemia should be kept within 12 hours. Cannulation before cardiac standstill was important to reduce the incidence of nonfunction and achieve high graft survival rates with NHBDD kidneys. The discontinuance of ventilator support also reduced the incidence of graft nonfunction. The combination of CsA or Tacrolimus and MMF as both the induction and maintenance regimen significantly improved graft survival. The use of either anti-T cell antibodies or basiliximab was also associated with significantly better graft survival for NHBDD kidneys. The combination of basiliximab, CsA and MMF resulted in a graft survival rate of 98% at one and 2 years.

Adolescent↗
PubMed2003

IL-6 signal transduction and its physiological roles: the signal orchestration model.

Interleukin (IL)-6 is a pleiotropic cytokine that not only affects the immune system, but also acts in other biological systems and many physiological events in various organs. In a target cell, IL-6 can simultaneously generate functionally distinct or sometimes contradictory signals through its receptor complex, IL-6Ralpha and gp130. One good illustration is derived from the in vitro observations that IL-6 promotes the growth arrest and differentiation of M1 cells through gp130-mediated STAT3 activation, whereas the Y759/SHP-2-mediated cascade by gp130 stimulation has growth-enhancing effects. The final physiological output can be thought of as a consequence of the orchestration of the diverse signaling pathways generated by a given ligand. This concept, the signal orchestration model, may explain how IL-6 can elicit proinflammatory or anti-inflammatory effects, depending on the in vivo environmental circumstances. Elucidation of the molecular mechanisms underlying this issue is a challenging subject for future research. Intriguingly, recent in vivo studies indicated that the SHP-2-binding site- and YXXQ-mediated pathways through gp130 are not mutually exclusive but affect each other: a mutation at the SHP-2-binding site prolongs STAT3 activation, and a loss of STAT activation by gp130 truncation leads to sustained SHP-2/ERK MAPK phosphorylation. Although IL-6/gp130 signaling is a promising target for drug discovery for many human diseases, the interdependence of each signaling pathway may be an obstacle to the development of a nonpeptide orally active small molecule to inhibit one of these IL-6 signaling cascades, because it would disturb the signal orchestration. In mice, a consequence of the imbalanced signals causes unexpected results such as gastrointestinal disorders, autoimmune diseases, and/or chronic inflammatory proliferative diseases. However, lessons learned from IL-6 KO mice indicate that IL-6 is not essential for vital biological processes, but a significant impact on disease progression in many experimental models for human disorders. Thus, IL-6/gp130 signaling will become a more attractive therapeutic target for human inflammatory diseases when a better understanding of IL-6 signaling, including the identification of the conductor for gp130 signal transduction, is achieved.

Acute-Phase Reaction↗
PubMed2003

Cell volume increase and extracellular Ca2+ are needed for hyposmotically induced prolactin release in tilapia.

In the tilapia (Oreochromis mossambicus), as in many euryhaline teleost fish, prolactin (PRL) plays a central role in freshwater adaptation, acting on osmoregulatory surfaces to reduce ion and water permeability and increase solute retention. Consistent with these actions, PRL release is stimulated as extracellular osmolality is reduced both in vivo and in vitro. In the current experiments, a perfusion system utilizing dispersed PRL cells was developed for permitting the simultaneous measurement of cell volume and PRL release. Intracellular Ca(2+) was monitored using fura 2-loaded cells under the same conditions. When PRL cells were exposed to hyposmotic medium, an increase in PRL cell volume preceded the increase in PRL release. Cell volume increased in proportion to decreases of 15 and 30% in osmolality. However, regulatory volume decrease was clearly seen only after a 30% reduction. The hyposmotically induced PRL release was sharply reduced in Ca(2+)-deleted hyposmotic medium, although cell volume changes were identical to those observed in normal hyposmotic medium. In most cells, a rise in intracellular Ca(2+) concentration ([Ca(2+)](i)) during hyposmotic stimulation was dependent on the availability of extracellular Ca(2+), although small transient increases in [Ca(2+)](i) were sometimes observed upon introduction of Ca(2+)-deleted media of the same or reduced osmolality. These results indicate that an increase in cell size is a critical step in the transduction of an osmotic signal into PRL release and that the hyposmotically induced increase in PRL release is greatly dependent on extracellular Ca(2+).

Animals↗
PubMed2003

Evidence that signal transduction for osmoreception is mediated by stretch-activated ion channels in tilapia.

Prolactin (PRL) plays a central role in the freshwater osmoregulation of teleost fish, including the tilapia (Oreochromis mossambicus). Consistent with this action, PRL release from the tilapia pituitary increases as extracellular osmolality is reduced both in vitro and in vivo. Dispersed tilapia PRL cells were incubated in a perfusion chamber that allowed simultaneous measurements of cell volume and PRL release. Intracellular Ca(2+) concentrations were measured from fura 2-loaded PRL cells treated in a similar way. Gadolinium (Gd(3+)), known to block stretch-activated cation channels, inhibited hyposmotically induced PRL release in a dose-related manner without preventing cell swelling. Nifedipine, an L-type Ca(2+) channel blocker, did not prevent the increase in PRL release during hyposmotic stimulation. A high, depolarizing concentration of KCl induced a transient and marked increase of intracellular Ca(2+) and release of PRL but did not prevent the rise in intracellular Ca(2+) and PRL release evoked by exposure to hyposmotic medium. These findings suggest that a decrease in extracellular osmolality stimulates PRL release through the opening of stretch-activated ion channels, which allow extracellular Ca(2+) to enter the cell when it swells.

Animals↗
PubMed2003

Canine cancellous bone microarchitecture after one year of high-dose bisphosphonates.

We examined the effects of one-year high-dose bisphosphonates (risedronate 0.5 mg/kg/day or alendronate 1.0 mg/kg/day) on the three-dimensional (3-D) microstructural and mechanical properties of canine cancellous bone. A high-resolution micro-CT scanner was used to scan cubic specimens produced from the first lumbar vertebrae. Microstructural properties of the specimens were calculated directly from the 3-D datasets and the mechanical properties of the specimens were determined. Our data demonstrate significant microarchitectural changes in the bisphosphonate-treated cancellous bone that was typically plate-like, denser, with thicker and more trabeculae compared with those of the controls. Consistent with architectural changes, the Young's moduli of cancellous bone increased in all three directions with the greatest increase in primary axial loading (cephalo-caudal) direction after treatment. Our results suggest a bone remodeling-adaptation mechanism stimulated by bisphosphonates that increases bone volume fraction, thickens trabeculae, changes trabeculae towards more plate-like, and increases mechanical properties. The secondary degree of anisotropy contributed significantly to the explained variance in bone strength, and the primary or tertiary degree of anisotropy improved the explanation of variances for Young's moduli, i.e., 79% of strength variances or 74-83% of modulus variances could be explained by the combined anisotropy and bone volume fraction. These significant improvements of cancellous bone architecture provide a rationale for the clinical observation that fracture risk decreased by 50% in the first year of bisphosphonate therapy with only a 5% increase in bone mineral density. We conclude that bisphosphonates enhance mechanical properties and reduce fracture risk by improving architectural anisotropy of cancellous bone 3-D microarchitecture.

Alendronate↗
PubMed2003

Pulsed liquid jet dissector using holmium:YAG laser--a novel neurosurgical device for brain incision without impairing vessels.

BACKGROUND: Neurosurgery has long required a method for dissecting brain tissue without damaging principal vessels and adjacent tissue, so as to prevent neurological complications after operation. In this study we constructed a prototype of such a device and used it in an attempt to resect beagle brain cortex. METHOD: The prototype device consisted of an optical fibre, a Y adaptor, and a nozzle whose internal exit diameter was 100 microm. Cold physiological saline (4 degrees C) was supplied to it at a rate of 40 ml/h. Pulsed liquid jets were ejected from the nozzle by a pulsed Holmium:YAG) (Ho:YAG) laser at an irradiation energy of 300 mJ/pulse. The profile of the liquid jet was observed with a high-speed camera while changing the distance between the optical fibre end and nozzle exit (equivalent to the standoff distance). With this device (3 Hz operation), brain dissection of anaesthetized beagles was attempted while measuring the local temperature of the target. A histological study of the incised parts was also performed. FINDINGS: When the standoff distance was 24 mm, the liquid jet was emitted straight from the nozzle at a maximum initial velocity of 50 m/s. The brain parenchyma was cut with this device while preserving vessels larger than 200 microm in diameter and keeping the operative field clear. The local temperature rose to no more than 41 degrees C, below the functional heat damage threshold of brain tissue. Histological findings showed no signs of thermal tissue damage around the dissected margin. INTERPRETATION: The Ho:YAG laser-induced liquid jet dissector can be applied to neurosurgery after incorporating some minor improvements.

Animals↗
PubMed2003

Effects of fasting on growth hormone/insulin-like growth factor I axis in the tilapia, Oreochromis mossambicus.

Effects of fasting on the growth hormone (GH)-insulin-like growth factor I (IGF-I) axis were examined in the tilapia (Oreochromis mossambicus) acclimated to fresh water. Fasting for 2 weeks resulted in significant reductions in body weight, specific growth rate and hepatosomatic index in both males and females. Significant reductions in specific growth rates were observed after 1 and 2 weeks in both sexes, although the decrease in body weight was not significant in the female. A significant reduction was also seen in the condition factor of females after 2 weeks. No change was seen in the gonadosomatic index in either sex. Two weeks of fasting also produced a significant reduction in plasma IGF-I but not in plasma GH, prolactin (PRL(188)) or cortisol. Significant reductions in the hepatic IGF-I mRNA were seen in both sexes. On the other hand, a significant increase was observed in cortisol receptor mRNA in the female liver. Plasma IGF-I levels were correlated significantly with specific growth rate, condition factor and hepatosomatic index, indicating that plasma IGF-I is a good indicator of growth in the tilapia. No change was seen in plasma glucose or osmolality after 2 weeks of fasting. During fasting, tilapia appears to convert metabolic energy from growth to basal metabolism including maintenance of ion and water balance.

Animals↗
PubMed2003

Effects of transfer from seawater to fresh water on the growth hormone/insulin-like growth factor-I axis and prolactin in the Tilapia, Oreochromis mossambicus.

The effect of freshwater (FW) transfer on growth and on the growth hormone (GH)/insulin-like growth factor-I (IGF-I) axis was examined in the tilapia, Oreochromis mossambicus. Tilapia were raised in seawater (SW) for 5 months and then transferred to FW for an additional 40 days. The growth rate of the fish transferred to FW was significantly reduced compared with the growth rate of fish that remained in SW. Plasma levels of GH were significantly elevated in FW-transferred fish, as were plasma IGF-I levels. Pituitary GH and liver IGF-I mRNA levels, on the other hand, were significantly reduced in the fish transferred to FW. There was a significant correlation between body mass and mRNA levels of GH and IGF-I, but not with plasma levels of GH and IGF-I. Fish transferred to FW had significantly higher prolactin (PRL)(177) levels than the SW control fish, although there was no difference in plasma PRL(188) levels. Consistent with the hyperosmoregulatory effects of PRL, mRNA levels of both PRL(177) and PRL(188) were significantly higher in FW-transferred fish than in the fish in SW. These results suggest that transferring tilapia from SW to FW activates the GH/IGF-I axis, but growth is still inhibited, possibly due to the greater metabolic cost of osmoregulation in FW than in SW.

Acclimatization↗
PubMed2003

Ventromedial hypothalamus lesions induce jejunal epithelial cell hyperplasia through an increase in gene expression of cyclooxygenase.

BACKGROUND: We demonstrated that ventromedial hypothalamus (VMH) lesions facilitate DNA synthesis, which reflects cell proliferation in abdominal organs, including the liver, pancreas, stomach, small intestine and large intestine, all of which are amply innervated by the vagal nerve. OBJECTIVE: To investigate which area DNA synthesis facilitates and what factors contribute to cell proliferation in the small intestine in VMH-lesioned rats. DESIGN: At 7 days after VMH lesions or sham operations, a segment of rat jejunum was taken for histological examination. A part of the jejunum was also removed from VMH-lesioned and sham-operated rats after 3 days and examined for 5-bromo-2'-deoxyuridine (BrdU) incorporation. At 6, 12 and 24 h after VMH lesions, the proximal intestine was removed from individual rats, from the pylorus to the mid-jejunum. Total RNA was extracted from these tissues of each rat, and the levels of epidermal growth factor (EGF) and transforming growth factor (TGF)-alpha mRNA were determined using reverse-transcription polymerase chain reaction. Cyclooxygenase (COX)-1 and -2 mRNA levels were determined using Northern blotting. RESULTS: : Jejunal villi in VMH-lesioned rats were markedly enlarged compared to those of sham-operated rats and jejunal crypts in VMH-lesioned rats more markedly incorporated BrdU. Northern blot analysis revealed an increase in COX-1 mRNA after 6, 12 and 24 h in the jejunum of VMH-lesioned rats. COX-2 mRNA was decreased 6 and 12 h after VMH lesioning; however, it was significantly increased 24 h after VMH lesions in comparison to sham-operated rats. The levels of EGF and TGF-alpha mRNA were unchanged in VMH lesioned rats. CONCLUSION: VMH lesions induced enlargement of jejunal villi and increased the gene expression of COX-1 in the small intestine. Prostaglandins, probably E(2), induced by COX-1 may be one candidate factor responsible for the cell proliferation of the small intestinal epithelium in these rats.

Animals↗
PubMed2003

The accuracy of long-term recall of past body weight in Japanese adult men.

OBJECTIVE: To examine the influences of recall period, current body weight, weight gain and loss, and weight variability on the accuracy of long-term recall of past weight. DESIGN AND SUBJECTS: Comparison of recalled weights around 25 y old with weights measured at age 25y in health checkup records among 2453 Japanese men (age: 34-61 y). MEASUREMENTS: Deviations between reported and measured weights were examined as to the three indexes: actual error (reported-measured), percent error (actual error/measured x 100), and absolute value of the percent error. Weight variability was defined as (1) the coefficient of variation of weight (CV) and (2) the root mean square error around the slope of weight on age (RMSE). RESULTS: Recalled weight strongly correlated with measured weight (r=0.849). Correlation coefficients decreased as age or the elapsed time since age 25y increased. Recalled weight (mean=58.3 kg) was slightly greater than measured weight at age 25y (mean=57.0 kg, mean actual error=1.28 kg). Subjects with a current body mass index (BMI) of less than 28.6 kg/m(2) overestimated their past weights, whereas those with BM1 of 28.6 kg/m(2) or over underestimated it. Subjects with weight loss since age 25y underestimated their past weights, whereas those with stable weight or gain overestimated it. There were monotonic increases in the three indexes of deviation across the CV quartile categories. Concerning the effect RMSE, a similar trend was observed. CONCLUSION: These results indicate that past body weights over a long period seem to be recalled with good accuracy. However, it should be kept in mind when using recalled weight in an epidemiologic study that accuracy of recall is influenced by age or elapsed time, current BMI, weight gain and loss, and weight variability.

Adult↗
PubMed2003

Administration of anti-interleukin 18 antibody fails to inhibit development of dermatitis in atopic dermatitis-model mice NC/Nga.

BACKGROUND: Interleukin (IL)-18 has been shown to activate basophils to produce histamine and IL-4 and to induce naive T cells to differentiate into T-helper (Th) 2 cells. However, when expressed together with IL-12, IL-18 induces Th1 cell development and inhibits IgE synthesis. Previously we reported that serum IL-18 levels were elevated in the sera from atopic dermatitis-model mice NC/Nga, prior to the onset and during the development of dermatitis. OBJECTIVES: We studied whether neutralization of IL-18 activity might affect dermatitis in NC/Nga mice, to investigate the role of IL-18 on dermatitis. METHODS: NC/Nga mice were given weekly anti-IL-18 antibody starting at 5 weeks of age to 13 weeks and development of dermatitis, scratching behaviour and serum IgE concentrations were evaluated. RESULTS: Continuous injections of anti-IL-18 antibody failed to inhibit the onset and development of dermatitis and IgE elevation. The treatment, rather, tended to lead to an exacerbation of dermatitis and scratching behaviour. In addition, the administration of anti-IL-18 antibody did not ameliorate the responsiveness of lymphocytes to IL-4, which was previously demonstrated as an immunological abnormality in the mouse. CONCLUSION: This study demonstrates that, at least in NC/Nga mice, IL-18, although excessively expressed before the onset of dermatitis, shows antiallergic actions.

Animals↗