Jun Suzuki

Prevention of Anti-IgM-Induced Apoptosis Accompanying G1 Arrest in B Lymphoma Cells Overexpressing Dominant-Negative Mutant Form of c-Jun N-Terminal Kinase 1

A family of mitogen-activated protein (MAP) kinases comprising the extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs), and p38 MAP kinases are involved in proliferation and apoptosis. However, there are some arguments concerning the role of these kinases in Ag-induced B cell apoptosis. Two of the B lymphoma cell lines (CH31 and WEHI-231) susceptible to anti-IgM-induced apoptosis were used as a model. To address these issues, we examined the kinetics of anti-IgM-induced activation of MAP kinases and established cell lines overexpressing a dominant-negative (dn) mutant form of JNK1 (dnJNK1). Anti-IgM induced a sustained JNK1 activation with a peak at 8 h, with a marginal activation of ERK1/ERK2 in CH31 cells. The sustained JNK1 activation was not a secondary event through a caspase activation. The peak point of the JNK1 activation was just before the onset of a decline in mitochondrial membrane potential, which preceded anti-IgM-induced cell death. Following anti-IgM stimulation, dnJNK1 prevented a decline in mitochondrial membrane potential at 24 h, with a prolonged inhibition up to 72 h in WEHI-231, although it did so only partially during a later time period in CH31. The dnJNK1 cells also demonstrated diminished procaspase-3 activation and a decreased rate of apoptosis upon anti-IgM stimulation, with a concomitant increased arrest in G1 phase, which could be explained by enhanced levels of cyclin-dependent kinase inhibitor p27Kip1 protein. Thus, anti-IgM-induced JNK activation might be implicated in cell cycle progression as well as in apoptosis regulation, probably involving p27Kip1 protein.

Rubella virus as a possible etiological agent of Fuchs heterochromic iridocyclitis

BackgroundTo determine whether rubella virus is involved in the pathogenesis of Fuchs heterochromic iridocyclitis (FHI).MethodsFourteen patients (14 eyes) diagnosed with FHI based on characteristic ocular manifestations and eight control subjects were studied. Aqueous humor (AH) samples from 14 FHI patients and one vitreous sample from a FHI patient were analyzed for intraocular antibody production against rubella virus by calculation of the Goldmann–Witmer coefficient (GWC). Viral detection by nested polymerase chain reaction and isolation by culture in RK-13 cells were conducted in nine FHI patients. In addition to laboratory examinations, medical history of rubella virus vaccination was also obtained.ResultsTen patients with FHI examined showed intraocular synthesis of rubella virus antibodies (GWC > 3). A high index of rubella virus antibody production was also found in the vitreous sample (GWC = 30.6). GWC in all control subjects were below detectable level. The rubella genome was detected in two of nine patients, and rubella virus was isolated from one of nine patients with FHI. None of the patients with FHI had been vaccinated against rubella.ConclusionsOur laboratory data strongly suggest a relationship between FHI and rubella virus.

A case of hypertensive keratouveitis with endotheliitis associated with cytomegalovirus.

Aim: While cytomegalovirus is well known as a pathogenic organism of retinitis, especially associated with human immunodeficiency virus infection, there are few reports of anterior uveitis associated with cytomegalovirus. Methods: The authors present a case of keratouveitis associated with cytomegalovirus. Results: A 70-year-old Japanese man was referred to the authors because of poorly controlled hypertensive keratouveitis in the left eye. The patient had a history of recurrent hypertensive anterior uveitis. At presentation, the corneal stroma was edematous, with Descemets folds and pigmented keratic precipitates. The anterior chamber angle was depigmented compared to the fellow eye. Even though pupil dilation and posterior synechiae were absent, iris atrophy was not evident. His right eye appeared normal except for moderate cataract. Funduscopy of the left eye was hazy, with the optic disc showing a normal color but poorly defined details, and no apparent exdative retinitis. The best-corrected decimal visual acuity of the right and left eyes was 0.4 and 0.02, respectively. Intraocular pressure was 11 mmHg in the right eye and 35 mmHg in the left, despite maximum medical therapy. Systemic acyclovir and prednisolone for a month did not improve the hypertensive keratouveitis. The aqueous humor was investigated for herpes simplex virus, varicella-zoster virus and cytomegalovirus. Cytomegalovius genome was detected by polymerase chain reaction analysis. Oral valganciclovir rapidly reduced ocular hypertension within a week. CMV DNA disappeared 3 months after the initiation of valganciclovir. Conclusion: The authors reported a case of hypertensive keratouveitis with endotheliitis associated with cytomegalovirus.

Uveitis associated with sarcoidosis exacerbated by etanercept therapy

fi ne-needle biopsy and histopathology to detect polymorphonuclear leukocytes, histiocytes, and plasma cells surrounding amorphous lens material. In the current report, Western blotting using multiple antibodies detected lensspecifi c proteins in the aqueous fl uid 2 months after trauma, whereas the same proteins were undetected in the aqueous fl uid of the control patients, suggesting that this method is both sensitive and specifi c. The normal upper limit for the α-crystalline concentration in aqueous fl uid is reported to be 10 ng/ml, and the α-crystalline concentration detected in this case (67 ng/μl) was far beyond that range; thus, a pathological correlation between the presence of a large amount of lens-specifi c proteins and uveitis is strongly suspected in this patient. Noninfectious hypopyon and multiple nodules on the iris surface developed postoperatively, and additional systemic steroid therapy was required. Additional reaction against lens-specifi c proteins during cataract surgery or against residual lens materials after surgery may explain the early postoperative exacerbation in this previously sensitized patient. Total protein levels are usually low in the physiological aqueous fl uid, and an increase of total protein levels in the aqueous fl uid itself has some diagnostic value; thus, we believe that loading an equal volume of aqueous fl uid is more suitable than loading equal amounts of total proteins for diagnostic Western blotting of lensinduced uveitis. This method may be another option for diagnosing patients suspected of having lens-induced uveitis.

Comparison of Patients with Ocular Tuberculosis in the 1990s and the 2000s

PurposeTo compare clinical findings in patients with ocular tuberculosis experienced during two different decades.MethodsThirty-four patients with ocular tuberculosis were divided into two groups: a 1990s group (n = 18) and a 2000s group (n = 16), according to the dates of their first outpatient visit. The clinical profiles of the two groups were then compared.ResultsMore cases of the 1990s group had complications involving extraocular tuberculosis than those of the 2000s group. While various ophthalmic manifestations were observed clinically in the 1990s group, all retinal periphlebitis cases presented in the 2000s group. The proportion of patients who received antituberculous treatment was higher in the 1990s group, but the proportion who received oral corticosteroid therapy did not differ between the two periods. However, more patients underwent laser photocoagulation in the 2000s group. The percentage of eyes with final visual acuity better than 20/20 increased in the 2000s group.ConclusionsThe clinical outcome of patients with ocular tuberculosis was improved in the 2000s group, which may be attributable to the increase in active use of laser photocoagulation therapy.

Circulating neutrophils in Behçet disease is resistant for apoptotic cell death in the remission phase of uveitis

BackgroundBehçet disease (BD) is manifested by recurrent acute iridocyclitis with hypopyon in the active phase, which regresses spontaneously. Hypopyon consists of inflammatory cells infiltrating the eye, with polymorphonuclear cells (PMNs) as the main component. The present study was conducted to investigate the apoptosis property of PMNs in BD patients with uveitis.MethodsPMNs were purified from peripheral blood cells of BD patients with uveitis in the active or remission phase and were cultured for 12 hours. In some cultures, lipopolysaccharide (LPS), antagonistic anti-TNFα antibody, agonistic anti-Fas antibody, or Fas:Fc fusion protein was added. At the end of cultures, apoptotic cells were evaluated by Annexin V expression using flow cytometry.ResultsSpontaneous apoptosis of PMNs showed lower levels in the remission phase of BD-related uveitis compared with the active phase or healthy controls. The lower level of PMN apoptosis in the remission phase of uveitis in BD remained even by stimulation with LPS, anti-TNFα antibody, or Fas:Fc fusion protein, which was abolished in the presence of agonistic anti-Fas antibody.ConclusionsIn BD patients, the apoptosis of PMNs was reduced in the remission phase of uveitis and restored in the active phase, which arose from the apoptotic cell death in part via Fas-Fas ligand interaction.

Serous retinal detachment in a patient with aplastic anemia associated with parvovirus B19 infection.

BackgroundWe report a case of unilateral serous retinal detachment (RD) associated with parvovirus B19 infection.Case reportA 28-year-old woman had a clinical history of autoimmune hemolytic anemia and pure red cell aplasia associated with parvovirus B19 infection. She demonstrated focal serous RD without retinal exudates. A focal cataract and anterior vitreous cells were also observed. Fluorescein angiography (FA) revealed accumulation of subretinal fluid, but no vascular leakage. After vitrectomy, the retina was re-attached and visual acuity returned to 20/20. IgM antibody to parvovirus and viral DNA were detected by polymerase chain reaction in the vitreous fluid obtained at surgery.ConclusionTo our knowledge, this is the first reported case of the presence of anti-viral IgM and viral DNA in vitreous sample. Furthermore, the ocular findings in our patient are definitively different from previously reported cases of parvovirus-associated ocular disorders.

Analysis of Retinal Findings of Acute Retinal Necrosis Using Optical Coherence Tomography

Purpose: To analyze the retinal findings in patients with ARN, optical coherence tomography (OCT) was performed. Methods: Seven patients (7 eyes) with ARN were studied using OCT. Results: OCT images depicted highly reflective areas in the inner layers of the retina in all seven cases, corresponding with the yellowish-white lesions of the retina in the acute phase. Disorganization of the retinal structure was also observed in these retinal lesions, especially in cases with severe inflammation. Subretinal changes including retinal exudate and/or fluid were observed in only one case. After regression of the yellowish-white lesions in the retina, a significant reduction in retinal thickness was observed on OCT. Conclusions: OCT permits the detection of full-thickness retinal necrosis in the acute phase and complete absence of retinal structure in the resolution phase, corresponding with the yellowish-white lesions seen in patients with ARN.

Oral administration of interferon-β suppresses experimental autoimmune uveoretinitis

Abstract.Background: The oral administration of type I interferons (IFNs) have been reported to reduce severity of inflammation in several animal models of autoimmune disease. This study examined whether oral administration of IFN-β is capable of modulating inflammation in experimental autoimmune uveoretinitis (EAU). Methods: EAU was induced in rats by immunization with interphotoreceptor retinoid-binding protein (IRBP) emulsified in complete Freunds adjuvant. Rats were treated with either varying doses (102, 103, 104 or 105 IU) of mouse recombinant IFN-β or phosphate-buffered saline for control, via direct oropharyngeal application once a day for 28 days starting 7 days before IRBP immunization. Intraocular inflammation was assessed by slit-lamp biomicroscopy and histopathological examination. Spleen cell proliferation response and cytokine production under IRBP stimulation were assessed. Spleen cell subpopulations were also measured. Results: IFN-β at doses of either 104 or 105 IU significantly reduced both the clinical and histopathological severity of EAU. Spleen cell proliferation and IFN-γ production from rats treated with 104 IU IFN-β were significantly decreased compared with controls. Furthermore, the proportion of both NK cells and NKT cells in the spleen of rats treated with IFN-β was increased compared with controls. Conclusion: These results suggest that the oral administration of IFN-β reduces inflammation in IRBP-mediated EAU and that the mechanism of this action may involve NK cells and NKT cells.

Steroid Sensitivity and Postoperative Course of Seven Patients with Behçet’s Disease

Systemic administration of steroids to patients with Behçet’s disease in Japan is often followed by a worsening in ocular symptoms. The sensitivity of 7 patients with Behçet’s disease to steroids which were administered during and after intraocular surgery was therefore measured, and their postoperative course was reviewed. Three of the 7 showed a low steroid sensitivity, and the frequency of postoperative inflammatory episodes and the intraocular pressure were both higher for this group than for the 4 who showed high steroid sensitivity.