Biomedical subjects

Mitsuru Sawa

Publications and source records attributed to Mitsuru Sawa.

26 records · Page 2Linked to original sources

PubMedDate not supplied

Expression of beta defensins in ocular surface tissue of experimentally developed allergic conjunctivitis mouse model.

PURPOSE: To investigate the expression of beta-defensin in the ocular surface of a mouse experimental allergic conjunctivitis (EAC) model. METHODS: Mouse beta-defensin (mBD)-1 and -2 mRNA expressed in conjunctival tissue of both the EAC and the control group were analyzed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) analysis. mBD-1 and mBD-2 mRNA expressed in cornea, limbus, and conjunctival epithelium of the EAC and the control group were also analyzed using a laser-assisted microdissection technique and the RT-PCR method. RESULTS: There was no significant difference in the amount of mBD-1 between the EAC and the control group. However, the EAC group had significantly less mBD-2 (0.23 +/- 0.15 x 10(4) copy/microl) than the control group (3.61 +/- 4.87 x 10(4) copy/microl) (P < 0.01, Mann-Whitney U test). mBD-1 mRNA was positive for all examined tissue in both groups. The expression of mBD-2 mRNA in the EAC group was definitely positive for the corneal and conjunctival epithelium and negative for the limbus. CONCLUSION: mBD-2 mRNA was expressed significantly less in the EAC model than in the control. Analysis by site in the ocular surface tissue revealed that this reduction was caused by the diminished expression of mBD-2 in the limbus.

Animals↗

PubMedDate not supplied

Antibody array-generated cytokine profiles of tears of patients with vernal keratoconjunctivitis or giant papillary conjunctivitis.

PURPOSE: To investigate differences in the cytokine and chemokine profiles of patients with vernal keratoconjunctivitis (VKC) or giant papillary conjunctivitis (GPC). METHODS: The study included six patients (six eyes) with VKC, five patients (five eyes) with GPC, and five healthy volunteers (five eyes) as controls. None of the patients had received any anti-allergic treatment prior to this study. One patient with VKC was given a tear examination to evaluate the effect of anti-inflammatory treatment with a steroid on the tear cytokine profile about the treatment. Tear samples were collected with the Schirmer I method, using filter paper. Tear samples were eluted and analyzed by an antibody array system for inflammation-related factors, including cytokines and chemokines. RESULTS: In the patients with VKC, four inflammation-related factors, eotaxin, interleukin (IL)-11, monocyte chemoattractant protein (MCP)-1, and macrophage-colony stimulating factor (M-CSF) increased to four times the values in the control group, and seven inflammation-related factors, eotaxin-2, IL-4, IL-6, interleukin-6 soluble receptor (IL-6sR), IL-7, macrophage inflammatory protein (MIP)-1delta, and tissue inhibitor of metalloproteinases (TIMP)-2, increased to eight times the control values. In the patients with GPC, three inflammation-related factors, IL-6, M-CSF, and monokine-induced gamma interferon (MIG), increased to four times those in the control group, and five inflammation-related factors, eotaxin-2, IL-6sR, IL-11, MIP-1delta, and TIMP-2, increased to eight times the control values. The increase in IL-6sR relative to the controls was statistically significant in both the VKC and GPC groups. The increase in eotaxin-2 was significant only in the VKC group, and that in TIMP-2 was significant only in the GPC group, compared with the controls. CONCLUSIONS: The present study demonstrated the presence of crucial cytokines, soluble cytokine receptors, and chemokines in tears of patients with VKC and GPC. In particular, IL-6sR increased significantly in both the VKC and GPC groups, whereas eotaxin-2 increased significantly only in the VKC group. Thus, IL-6sR may play an important pathophysiological role in giant papillary proliferation in VKC and GPC, and eotaxin-2 may play an important role in eosinophilic inflammation in VKC.

Adolescent↗

PubMedDate not supplied

Evaluation of staphylococcal enterotoxin-specific IgE antibody in tears in allergic keratoconjunctival disorders.

PURPOSE: To investigate the presence of staphylococcal enterotoxin A (SEA) and B (SEB)-specific IgE antibodies in tears from patients with allergic conjunctival disorders. METHODS: The study included 8 eyes of 4 patients with perennial allergic conjunctivitis (PAC), 14 eyes of 7 patients with vernal keratoconjunctivitis (VKC), 12 eyes of 6 patients with atopic keratoconjunctivitis (AKC), and 10 eyes of 10 healthy volunteers as controls. Tears were sampled by the method of the Schirmer test I. Sampled tears were eluted and SEA- and SEB-specific IgE antibodies were analyzed by the AlaSTAT-IMMULIZE method. RESULTS: SEA-specific IgE antibodies in tears were positive in 9 of 14 eyes in VKC patients and in 1 of 12 eyes in AKC patients. SEB-specific IgE antibodies in tears were positive in 7 of 14 eyes in VKC patients and in 2 of 12 eyes in AKC patients. Values for antibodies were higher in patients with severe clinical findings. However, all the cases in the normal control and the PAC groups were negative for both antibodies. CONCLUSION: Our data strongly suggested that staphylococcal enterotoxin may cause type I allergy, and may be an exacerbating factor for vernal keratoconjunctivitis and atopic keratoconjunctivitis.

Adult↗

PubMedDate not supplied

Development of novel corneal storage medium: first report. Examinations of rabbit cornea.

PURPOSE: To develop a new corneal storage medium with a simple formula and evaluate it by histological methods. METHODS: Two corneal storage media containing minimum essential medium and 2.5% chondroitin sulfate (pH 7.33), with osmolarity of 320 mOsm/kg, were compared to Optisol-GS. The differences in the two media were the molecular weight (MW) and the source of chondroitin sulfate. The MW of Medium I was 27,500 and the MW of Medium II was 33,700. Japanese albino rabbits were used in this study. A cornea with scleral rim obtained from a rabbit was stored in either Medium I or Medium II and the fellow cornea was stored in Optisol-GS for 7 or 14 days at 4 degrees C. Histological examination of corneal endothelial cells was performed both by scanning electron microscopy and by transmission electron microscopy. RESULTS: At day 7, there was no significant difference in histological findings among the rabbit corneas stored in Optisol-GS, Medium I, or Medium II. At day 14, corneas stored in Optisol-GS or Medium I showed similar histological findings. In Medium II, endothelial cells showed marked degeneration. CONCLUSIONS: The results of experiments with rabbit cornea indicated that Optisol-GS and Medium I could preserve endothelial cellular structure better than Medium II. The difference between Medium I and Medium II was only the MW of the chondroitin sulfate used. The MW may be an important factor for determining suitable chondroitin sulfate for use in a corneal storage medium.

Animals↗

PubMedDate not supplied

Histological study of conjunctiva-associated lymphoid tissue in mouse.

PURPOSE: To investigate conjunctiva-associated lymphoid tissue (CALT) in the mouse conjunctiva by histological methods. METHODS: The presumed follicular tissue in the conjunctiva of normal mice, age ranging from 4 to 6 weeks, was histologically investigated by the hematoxylin-eosin staining method. Next, we treated the mice with topical instillation of a combined solution of ovalbumin and cholera toxin B to investigate the morphological changes of conjunctival follicles to antigen challenge. The treated mice underwent sequential clinical examinations, and the conjunctival follicular tissue was examined by an immunohistochemical method using anti-CD4 antibody, anti-CD8 antibody, and anti-S-100 antibody. RESULTS: Follicular tissue was present on the mouse nictitating membrane. Both size and number of follicular tissue areas increased with topical ovalbumin treatment. Immunohistochemical study revealed CD4, CD8, and S-100 positive cells in the follicular tissue. The epithelial layer, corresponding to follicular tissue, demonstrated intra-epithelial pocket and the presence of CD4-positive cells in the intra-epithelial pocket. CONCLUSION: Follicular tissue at the nictitating membrane is CALT in the mouse.

Animals↗

PubMedDate not supplied

Efficacy of tear eosinophil cationic protein level measurement using filter paper for diagnosing allergic conjunctival disorders.

PURPOSE: We investigated the efficacy of the tear sampling method using a filter paper to evaluate eosinophil cationic protein (ECP) levels in patients with allergic disorders. METHODS: Subjects were an allergic group comprising patients with allergic conjunctivitis, vernal keratoconjunctivitis, or atopic keratoconjunctivitis, a Sjögren group comprising patients with secondary Sjögren syndrome, and a control group comprising healthy volunteers. Tears were sampled using the Schirmer Method I and the sample was eluted from the filter paper in 50 microL of elution solution containing phosphate buffer solution with 0.5 M NaCl + 0.1% Tween 20. Then the ECP concentration in the elution sample was determined by the enzyme-linked immunosorbent assay method. RESULTS: Tear ECP level in the allergic group was significantly higher than the levels in the other two groups (P <.01 for the Sjögren group and P <.001 for the control). Furthermore, the tear ECP level of each allergic disease subgroup in the allergic group was significantly higher than that in the control group. CONCLUSIONS: This method of determining tear ECP concentration is useful not only to diagnose allergic conjunctival disorders but also to evaluate their clinical stages.

Adolescent↗

PubMedDate not supplied

A novel nonsense mutation with a compound heterozygous mutation in TGFBI gene in lattice corneal dystrophy type I.

PURPOSE: We examined transforming growth factor beta-induced (TGFBI) gene mutations in a family with lattice corneal dystrophy type I. METHODS: The proband was one of the offspring of a consanguineous marriage; 4 affected and 3 unaffected individuals of the family were investigated. Genomic DNA of each case was extracted and used for polymerase chain reaction (PCR). The exon 4, 11, and 12 of the TGFBI gene were directly sequenced. The mutations were confirmed by PCR restriction fragment length polymorphism analysis. RESULTS: There was no significant difference in phenotype between the proband and the other 2 patients, except for progression of the corneal opacity with age. R124C mutation was detected in all affected individuals. In addition, G470X, a novel nonsense mutation, was detected in the proband, resulting in the proband being a compound heterozygote with the TGFBI gene. Her unaffected daughter was found to be heterozygous for G470X. CONCLUSION: It is most likely that the novel nonsense mutation is not pathogenic, and that the mutant keratoepithelin protein with R124C is responsible for the phenotype.

Adolescent↗

PubMedDate not supplied

Active form of gelatinases in tear fluidin patients with corneal ulcer or ocular burn.

PURPOSE: To investigate the expression of the active form of gelatinases (gelatinase A: matrix metalloproteinase-2 [MMP-2] and gelatinase B: matrix metalloproteinase-9 [MMP-9]) in ocular surface disorders, we determined the presence of the active form of these gelatinases in the tear fluid of patients with corneal ulcer or ocular burn. METHODS: The subjects consisted of the ulcer group comprising 13 eyes, the burn group comprising 6 eyes, and the normal group comprising 10 eyes. Tear samples were taken by the method of the Schirmer test I. The tears were eluted using extraction buffer containing 0.01 M phosphate buffer solution (pH 7.2), 1% Tween 20 and 1 M NaCl, and analyzed by gelatin zymography. RESULTS: Only the proforms of MMP-2, and MMP-9 were detected in the normal group and in uncomplicated herpetic keratitis or herpetic keratitis cases complicated by mixed infection in the ulcer group. Active MMP-9 was detected in mild corneal ulcer cases and mild ocular burn cases. Both active MMP-2 and active MMP-9 were detected in endogenous corneal ulcer cases and severe burn cases, including perforation cases. CONCLUSIONS: Both active gelatinases were detected in tears of severe corneal ulcer or severe ocular burn cases. The active form of gelatinase expression may be related to the severity of ulceration.

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