Different reactivity with monoclonal anti-tubulin antibodies between native and fixed mitotic microtubules in sea urchin eggs

The effect on fixation on the reactivities of mitotic microtubules with monoclonal anti-tubulin antibodies was investigated by the indirect immunofluorescence procedure. All of the seven antibodies used intensely stained mitotic microtubules in sea urchin eggs lysed and fixed with methanol at -20 degrees C, whereas only two of them stained the stabilized microtubules in the lysed eggs before the fixation. The other five did not stain the mitotic microtubules even after microtubule components other than tubulin were removed by treating the lysed eggs with 0.4 M KCl solution containing taxol. These results exclude the possibility that the fixation affects proteins, which interact with microtubules including microtubule-associated proteins (MAPs) and interfere with the binding of monoclonal antibodies with tubulin, and strongly suggest that the fixation directly affects the three-dimensional conformation of tubulin. Furthermore, microinjection of these antibodies indicated the results as follows [combining the results reported previously; Oka et al., 1990: Cell Struct. Funct. 15: 373-378]: The antibodies which stained mitotic microtubules stabilized in the lysed eggs induced disassembly of native mitotic microtubules in the living eggs, but those which did not stain the stabilized microtubules did not disassemble the native microtubules. From these results, it is suggested that the monoclonal antibodies which stain microtubules in the eggs lysed but not fixed are useful for microinjection experiments.

Quantitation and immunocytological identification of interleukin-1 in nasal polyps from patients with chronic sinusitis

Immunoreactive interleukin-1 (IL-1) alpha and beta levels in nasal polyp (NP) extracts were measured from 22 adult patients with chronic sinusitis (CS) in order to determine their significance in the pathogenesis of NP. The NP sample was separated into mononuclear and polymorphonuclear fractions. In the mononuclear fraction, the mean value of IL-1 beta was 21.5 pg/ml/g, which was significantly higher than that of IL-1 alpha (8.4 pg/ml/g, p < 0.01). In younger adults, the IL-1 alpha and IL-1 beta levels were 21.2 and 59.4 pg/ml/g, which were significantly higher than those in older CS patients (p < 0.01). There was a significant reverse correlation between patient's age and IL-1 beta levels in the mononuclear fraction (r = -0.509, p < 0.01). Immunoreactive IL-1, mainly IL-1 beta, was identified in the cytoplasmic area of monocytes. A certain amount of immunoreactive IL-1 is produced in mononuclear leukocytes, particularly activated monocytes, and IL-1 beta production is greater than IL-1 alpha. In younger adult CS patients, NPs contain larger amounts of IL-1 beta in monocytes, compared to those of older patients.

A rho-like protein is involved in the organisation of the contractile ring in dividing sand dollar eggs

Sand dollar eggs were microinjected with botulinum C3 exoenzyme, an ADP-ribosyltransferase from Clostridium botulinum that specifically ADP-ribosylates and inactivates rho proteins. C3 exoenzyme microinjected during nuclear division interfered with subsequent cleavage furrow formation. No actin filaments were detected in the equatorial cortical layer of these eggs by rhodamine-phalloidin staining. When microinjected into furrowing eggs, C3 exoenzyme rapidly disrupted the contractile ring actin filaments and caused regression of the cleavage furrows. C3 exoenzyme had no apparent effect on nuclear division, however, and multinucleated embryos developed from the microinjected eggs. By contrast, C3 exoenzyme did not affect the organisation of cortical actin filaments immediately after fertilisation. Only one protein (molecular weight 22,000) was ADP-ribosylated by C3 exoenzyme in the isolated cleavage furrow. This protein co-migrated with ADP-ribosylated rhoA derived from human platelets when analysed by two-dimensional gel electrophoresis. These results strongly suggest that a rho-like, small GTP-binding protein is selectively involved in the organisation and maintenance of the contractile ring.

Calcium ion regulation of chirality of beating flagellum of reactivated sea urchin spermatozoa

Near an interface, sea urchin spermatozoa swim almost in circles. The direction is usually clockwise at the lower surface of a coverslip and counterclockwise at the upper surface of a glass slide, when viewed from above. Examination of demembranated spermatozoa has shown that Ca2+ regulates the direction of the circular motion of spermatozoa reactivated with adenosine triphosphate (ATP). This finding suggests that Ca2+ changes the chirality of the three-dimensional bending waves of sperm flagella.

Human Jk recombination signal binding protein gene (IGKJRB): comparison with its mouse homologue

The mouse Igkjrb protein specifically binds to the immunoglobulin Jk recombination signal sequence. The IGKJRB gene is highly conserved among many species such as human, Xenopus, and Drosophila. Using cDNA fragments of the mouse Igkjrb gene, we isolated its human counterpart, IGKJRB. The human genome contains one functional IGKJRB gene and two types of processed pseudogenes. In situ chromosome hybridization analysis demonstrated that the functional gene is localized at chromosome 3q25, and the pseudogenes (IGKJRBP1 and IGKJRBP2, respectively) are located at chromosomes 9p13 and 9q13. The functional gene is composed of 13 exons spanning at least 67 kb. Three types of cDNA with different 5' sequences were isolated by rapid amplification of cDNA ends, suggesting, the presence of three proteins. The aPCR-1 protein, which possessed the exon 1 sequence, was the counterpart of the mouse RBP-2 type protein. The aPCR-2 and 3 proteins may be specific to human cells because the mouse counterparts were not detected. The amino acid sequences of the human and mouse IGKJRB genes were 98% homologous in exons 2-11, whereas the homology of the human and mouse exon 1 sequences was 75%.

[A case of oral tuberculosis suspected malignancy]

Oral tuberculosis with pulmonary tuberculosis is very rare in Japan. A 45-year old man admitted to our hospital because of spontaneous teeth extraction and pain in oral cavity for the past 3 months. The painful granulation in palate and fistel of 7th tooth root defect in right upper gum were observed. The diagnosis of oral tuberculosis was made by the histological examination of biopsy material and positive smear test for M. tuberculosis in surface of granulation. Chest X-ray showed multicavitary lesions in bilateral upper lobs and spread shadows in bilateral lower lung fields. He was treated with chemotherapy (INH, RFP, SM and EB) and with tube feeding. Five month's chemotherapy was needed to achieve cured granulation and negative smear test for M. tuberculosis in sputum. He was discharged 10 months after admission.

Quantification of interleukin-1 in nasal polyps from patients with chronic sinusitis

We have measured interleukin-1 alpha (IL-1 alpha) and beta levels in nasal polyps (NP) from patients with chronic sinusitis (CS) in order to determine their significance in the pathogenesis of NP. NP in ten cases (five male and five female; age range, 17-63 years) were removed to separate mononuclear (M) and polymorphonuclear (PMN) fractions through Ficoll-Paque separation media. ELISA measurements of the M fraction showed that the mean value of IL-1 beta was 17.8 pg/ml per gram, which was significantly higher than that of IL-1 alpha (7.04 pg/ml per gram, P < 0.01, Wilcoxon test). In the PMN fraction, the mean value of IL-1 alpha was 8.79 pg/ml per gram and that of IL-beta was 7.85 pg/ml per gram, which was not significantly different. Mononuclear leukocytes, particularly activated monocytes, seem to be a major source of IL-1 in the NP taken from patients with CS.

Mitotic apparatus formation and cleavage induction by micromanipulation of the nucleus and centrosome: the centrosome forms a spindle together with only the chromosomes at a short distance

We micromanipulated the nucleus and centrosomes in the zygote of the starfish, Asterina pectinifera, in order to investigate their roles in mitotic apparatus formation and cleavage induction. The zygote cleaved without spindle formation when its nucleus was removed. When one or two centrosomes were transplanted, they formed asters in the recipient cell, which cleaved into three or four blastomeres so that each blastomere might contain one centrosome or aster. When one centrosome was removed, a half-spindle formed in the manipulated cell, which did not cleave until the other centrosome was duplicated. When both centrosomes were removed, no microtubular structures such as the spindle and the aster appeared in the manipulated cell, which failed to cleave. These results indicate that two centrosomes or more in the cell induce cleavage with or without the nucleus and that one centrosome or less does not induce cleavage. It is also concluded that the centrosome(s) together with the nucleus forms a half-spindle or bipolar spindle. However, from the experiments of nucleus transplantation and displacement, spindle formation is found to depend on the distance between chromosomes and centrosomes. The half-spindle formed when the distance from the centrosome to the chromosomes was shorter than 22 microns; on the other hand, when the distance was longer than 22 microns, the nucleus remained apart from the aster, which means that the functional range of the astral microtubule's ability to engage chromosomes was 22 microns from the centrosome.

Neutrophil elastase and its complex with alpha 1-antitrypsin in the pathogenesis of chronic suppurative otitis media

Neutrophil elastase (NE) and its complex with alpha 1-antitrypsin were quantified in ear discharges from 15 patients with chronic suppurative otitis media (CSOM), and their levels were compared to those in middle ear effusions from 10 pediatric patients with chronic otitis media with effusion (OME). The localization of immunoreactive NE was also examined by immunocytologic study. The mean value of total NE was 161.8 +/- 29.5 micrograms/mL in CSOM, which was significantly higher than that in OME (16.5 +/- 6.7 micrograms/mL). The mean value of NE-alpha 1-antitrypsin complex was 13.7 +/- 8.8 micrograms/mL in CSOM and 7.8 +/- 4.0 micrograms/mL in OME. There was no significant difference between culture-positive and culture-negative samples in CSOM. Immunoreactive NE could be observed in the neutrophils of ear discharges, and extracellular release of NE was also observed. Ear discharges in CSOM contain a considerable amount of uncomplexed NE, of which the level does not depend on active bacterial infections. Uncomplexed NE seems to play a role in the chronicity of CSOM.

Relationship between direction of rolling and yawing of golden hamster and sea urchin spermatozoa

As a first step towards understanding the function and mechanism of spiral movement of spermatozoa swimming through a medium, the direction of rolling (rotational movement of the spermatozoa around their long axis) and that of yawing (circular motion of spermatozoa upon the surface of a glass microscope slide and coverslip) were examined for golden hamster and sea urchin spermatozoa. Most golden hamster spermatozoa yawed clockwise over the upper surface of a glass slide when viewed from above, whereas in most sea urchin spermatozoa yawing was counterclockwise. Under the lower surface of a coverslip, the direction of yaw of golden hamster or of sea urchin spermatozoa was reversed. Most golden hamster spermatozoa rolled counterclockwise as seen from the anterior end, whereas all examined sea urchin spermatozoa rolled clockwise relative to the observer. On the basis of quantitative analysis of the proportion of spermatozoa rolling (or yawing) clockwise to those rolling (or yawing) counterclockwise, a close relationship between the direction of rolling motion and that of yawing motion was shown for both golden hamster and sea urchin spermatozoa.

Biochemical and immunological characterization of the DNA binding protein (RBP-J kappa) to mouse J kappa recombination signal sequence

We have investigated whether J kappa recombination signal sequence (RS) binding protein (RBP-J kappa) has any partial catalytic activities involved in the VDJ recombination reaction, such as cleavage, ligation, and bending of DNA. Murine RBP-J kappa protein purified by J kappa-RS affinity chromatography did not show DNA cleavage activities but contained a strong DNA ligase activity. To obtain a large amount of purified RBP-J kappa protein, recombinant RBP-J kappa was synthesized in Escherichia coli as a fusion protein and also in silkworm cells. Although recombinant RBP-J kappa produced in silkworm cells could bind J kappa-RS, it failed to show either ligase or DNA bending activity. Since the DNA affinity-purified RBP-J kappa has the ligase activity, the RBP-J kappa protein may form a complex with a ligase in vivo. We have raised monoclonal antibodies against the RBP-J kappa fusion protein which was synthesized in E. coli and unable to bind J kappa-RS. Using the anti-RBP-J kappa monoclonal antibody we have shown that the RBP-J kappa protein is expressed ubiquitously in mammalian tissues. The ubiquitous expression of the RBP-J kappa protein is consistent with the hypothesis that the RBP-J kappa protein may have dual function [Furukawa et al. (1991) J. Biol. Chem. 266, 23334-23340].

High survival of rabbit morulae after vitrification in an ethylene glycol-based solution by a simple method

Rabbit morulae were exposed to a vitrification solution-modified PBS [PB1] medium containing 40% ethylene glycol + 18% Ficoll + 0.3 M sucrose (EFS) for 2, 5, or 10 min at 20 degrees C and were vitrified in liquid nitrogen. When morulae were rapidly warmed, 96% had an intact zona pellucida. When embryos were cultured after removal of the mucin coat, high proportions of them formed blastocoel (79-100%), but the percentage of embryos developed to fully expanded blastocysts decreased with increased exposure time 87%, 40%, and 17%). The survival rate of morulae vitrified after removal of the mucin coat was lower than that of mucin-intact embryos. To assess the development potential in vivo, 131 embryos were vitrified after 2 min of exposure to EFS solution; all the embryos were recovered and 120 were transferred to recipients without removal of the mucin coat, resulting in 78 (65%) full-term fetuses or young. This simple method, which yields high survival both in vitro and in vivo, will be of practical use for vitrifying rabbit embryos.

Genomic organization of mouse J kappa recombination signal binding protein (RBP-J kappa) gene

We have isolated a cDNA clone (RBP-2) for the protein (RBP-J kappa) which binds to immunoglobulin recombination signals with 23-base pair spacers (Matsunami, N., Hamaguchi, Y., Yamamoto, Y., Kuze, K., Kangawa, K., Matsuo, H., Kawaichi, M., and Honjo, T. (1989) Nature 342, 934-937). During further screening of a cDNA library from the same mouse pre-B cell line (38B9), we have isolated a second cDNA clone (RBP-2N) which differs from RBP-2 in its 5' sequence. RNase protection assays indicated that the RBP-2N type mRNA was produced in 10-20 times the quantity as RBP-2 mRNA. To elucidate the relationship between these two mRNAs, we analyzed the genomic organization of the RBP-J kappa gene. Southern hybridization of mouse genomic DNA detected at least 7 EcoRI fragments hybridizing to an RBP-2 cDNA probe, suggesting a complex structure for the RBP-J kappa gene. Cloning of each EcoRI fragment revealed one functional RBP-J kappa gene and three related genes. The functional gene was composed of 11 exons and spanned at least 50 kilobase pairs. The sequence of exon 1 and its 5'-flanking region contained a GC-rich promoter-like region but no apparent TATA box. The initiation site of transcription was heterogeneous, and the two types of mRNA are produced from the same exon by transcription initiation at different sites and by different usage of splice signals. Two of the three related genes were processed pseudogenes with scattered stop codons. The other was also a processed gene with a sequence exactly the same as that of RBP-2, except that this gene lacked the sequence corresponding to the first exon of the functional gene.

Rotational movement of a spermatozoon around its long axis

The rotational movement of a spermatozoon around its longitudinal axis was investigated by two methods: by observing a spermatozoon attached vertically to a coverslip by the tip of its head, and by observing a spermatozoon freely swimming in a medium by means of ‘double-focal microscopy’, which yielded simultaneous images at two different focal planes. Similar results were obtained by these two methods. Sea urchin, starfish, medaka, human, golden hamster and bull spermatozoa rolled in both clockwise and counterclockwise directions, although there was a large difference in the proportion of spermatozoa rolling in each direction in the different species. The majority of sea urchin and starfish spermatozoa rolled in a clockwise direction when an observer viewed the cell from its anterior end, whereas the majority of medaka, golden hamster, human and bull spermatozoa rolled in a counterclockwise direction relative to the same observer. Moreover, some spermatozoa occasionally changed their rotational direction. These results suggest that the mechanism regulating the direction of rotation of the spermatozoa is lax. As rotational movement of a spermatozoon around its longitudinal axis is due to the three-dimensional component of the beat of the flagellum, the direction of the three-dimensional movement presumably changes as the spermatozoa swim.

[Rapid spontaneous postpartum remission in a case of chronic inflammatory demyelinating polyradiculoneuropathy associated with pregnancy]

A 28-year-old woman developed numbness and weakness of the hands and arms when she was 8 months pregnant, and weakness worsened gradually. However, weakness started to spontaneously subside immediately after delivery and she felt almost recovered several hours later. But weakness and numbness recurred one week after delivery and she was admitted to our hospital. Neurological examination revealed moderate weakness and disturbance of the deep and cutaneous sensations in the upper and lower extremities, and marked decrease of the deep tendon reflexes. The upper extremities were more severely affected. Nerve conduction study showed marked decrease in the motor conduction velocities. Cerebrospinal fluid showed increase of protein without pleocytosis. Teased preparation of the biopsied sural nerve showed occasional internodal segments with thin myelination, indicating demyelination and remyelination. A diagnosis of chronic inflammatory demyelinating polyradiculoneuropathy was made. Treatment with prednisolone markedly improved the weakness and hyporeflexia as well as the cerebrospinal fluid protein. Postpartum rapid remission may have been produced by rapid increase of endogenous steroid hormone in the blood by its massive excretion during delivery.

[Effect of recognition of head and neck malignancies on patients' psychosomatic condition and personality]

In order to elucidate the effect of recognition of head and neck malignancies on patients' psychosomatic condition and personality, we applied the Cornell Medical Index Health Questionnaire (CMI) and the Maudsley Personality Inventory (MPI) and collected medical and psychological data from 35 male (42-78 years of age; average 62.5) and 15 female (20-76 years of age; average 54.7) patients with malignant head and neck tumors (10 nose and paranasal, 8 oral, 8 pharyngeal, 14 laryngeal, 6 thyroid gland and 4 others). The two tests were done twice for each patients; at first immediately before hospitalization for treatment of the tumors at Mie University Hospital and secondly just before discharge from the hospital. The period of hospitalization ranged 1 to 13 months, average 3.3 months. At the end of hospitalization doctors and nurses who had mainly taken care of the patients estimated the patients' recognition of their malignancy by analyzing behavior and information mainly from their family and classified patients into three groups; Group R (Patients who recognized that they were patients with head and neck malignancies) comprised 22 patients, Group N (who did not recognize the condition) comprised 15 and Group U (who could not be classified into Groups R or N) comprised 13. Comparison among the three groups revealed the followings. 1) Patients in Group R were relatively young (average 56.3 years) and extrovert (estimated by MPI) and their somatic and psychological complaints registered on the CMI were less than those in other 2 groups. Psychosomatic condition after recognition that they had been patients with malignant tumors was better than before.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of lobar cerebral hemorrhage with low concentration of CSF cystatin C]

A 49-year-old male was admitted to our hospital because of severe headache and dizziness which had occurred suddenly one day before admission. There was no past history contributory to cerebral hemorrhage but was family history of cerebrovascular accidents in his father and brother. Neurological examination revealed left homonymous hemianopsia, mild left hemiparesis, and left side hemi-neglect in simultaneous stimuli on bilateral extremities. Laboratory data including peripheral blood cells, coagulation tests, and serum chemistry were unremarkable. Brain CT and MRI demonstrated large lobar hematoma in the right parieto-occipito-temporal region. Cystatin C level in the CSF samples taken on the 39th and 59 th days (38 and 27 ng/ml respectively) were low, compared with the normal value (greater than 100 ng/ml). These findings suggest that the lobar cerebral hemorrhage of the present case might have been caused by cerebral amyloid angiopathy with cystatin C deposits.

Propagation of transient Ca2+ increase in sea urchin eggs upon fertilization and its regulation by microinjecting EGTA solution

Upon fertilization, the concentration of intracellular Ca2+ (Cai) in sea urchin eggs increased up to 3 microM when measured with fura-2, a fluorescent Ca indicator and the increase in Cai traversed from the sperm entry point as a wave over the entire egg at the mean propagation velocities of 5.0 microns/sec in C. japonicus egg and 5.3 microns/sec in H. pulcherrimus egg. However, the velocity was not uniform; i.e., it was rapid in the vicinity of the sperm entry point and the opposite point, but slow in the central region of the egg. Microinjecting a Ca-EGTA buffer and an IP3 solution into the C. japonicus egg induced the transient Cai increase more rapidly than that upon fertilization, due perhaps to the diffusion of the injectates. In order to investigate Ca2+ release during Cai increase upon fertilization, EGTA solutions were microinjected into unfertilized or fertilizing eggs. Microinjecting 100 mM EGTA (final concentration of 1 mM) not only suppressed the transient Cai increase, but also reduced the increased Cai rapidly, and never induced egg activation after insemination, whereas 10 mM EGTA (final concentration of 0.1 mM) did not significantly affect the Cai increase or the activation. Ca2+ released upon fertilization was estimated to be 150-170 microM in the egg cytoplasm from the amount of microinjected EGTA and fura-2. It was concluded that although more than 150 microM of Ca2+ was released intracellularly upon fertilization, Cai increased to only a few microM because most of the released Ca2+ was sequestered by intracellular Ca2+ binding substances.

Change in the heterogeneous distribution of tubulin isotypes in mitotic microtubules of the sea urchin egg by treatment with microtubule depolymerizing or stabilizing drugs

In the mitotic sea urchin egg, the spindle microtubules were composed of different tubulin isotypes from those of astral microtubules using monoclonal antibodies [Oka et al. (1990) Cell Motil. Cytoskeleton, 16, 239-250]. Three of the antibodies, D2D6, DM1B, and YL1/2, were specific for spindle microtubules, astral microtubules and reactive with both microtubules, respectively. The mitotic sea urchin egg was treated with microtubule depolymerizing (colcemid and nocodazole) and stabilizing (hexylene glycol) drugs and change in the heterogeneous distribution of the tubulin isotypes was investigated by the immunofluorescence procedure using these three monoclonal anti-tubulin antibodies. We observed that: (1) the microtubule depolymerizing drugs caused quick depolymerization of most mitotic microtubules, and a small number of spindle microtubules remaining were stained with all three antibodies; (2) hexylene glycol induced many microtubules in the mitotic apparatus, which was stained with D2D6 but was not stained with DM1B; (3) hexylene glycol also induced a great number of miniasters in the cytoplasm, and they were stained with three antibodies. These results suggest that these drugs altered the distribution of tubulin isotypes in the mitotic microtubules during depolymerization or polymerization within a short time.

Chromosomal behavior in starfish (Asterina pectinifera) zygotes under the effect of aphidicolin, an inhibitor of DNA polymerase

When calf thymus histones were labeled fluorescently and microinjected into oocytes of the starfish, Asterina pectinifera, the labeled histones visualized chromosomes during maturation division and cleavage. In doing so, we confirmed the previously reported phenomenon that chromosomes became incompetent at the first cleavage in the aphidicolin-treated egg, although cleavage itself took place. Moreover, we found that chromosomes were aligned at the equator of the metaphase spindle of the first cleavage and that they did not separate into two groups at all, but made a lump in the middle of the spindle. Chromosomes finally entered one blastomere, although they did not participate in the following karyokinesis. DNA and microtubules were examined by cytochemistry and immunofluorescence in order to investigate the relation between chromosome movement and the microtubular cytoskeleton. The mitotic apparatus developed and grew in the aphidicolin-treated cells in the same manner as those in normal cells without normal chromatin condensation or chromosome movement during the first cleavage. However, the mitotic apparatus consisted of two asters without the spindle formed at subsequent cleavages. Electron microscopic study revealed that chromosomes did not condense normally and kinetochores were not detected during the first cleavage. These results indicate that the dynamic changes in microtubular structures during mitosis have poor relation with the chromosome behavior such as prophase chromosome condensation and anaphase chromosome movement.

Cloning and characterization of a protein binding to the J kappa recombination signal sequence of immunoglobulin genes

A protein with molecular weight of 60,000 that binds to the recombination signal sequence (RS) of the immunoglobulin J kappa segment was purified from the nuclear extract of a murine pre B cell line 38B9. This binding protein was found in lymphoid cell lines but not in non-lymphoid cell lines. The Kd value of the J kappa RS binding protein to the J kappa RS was 1 nM. The cDNA clone (RBP-2) was isolated based on partial amino-acid sequence of this protein. This cDNA encodes 526 amino-acid residues, and its sequence does not show extensive overall homology with any known proteins, but displays an interesting homology to a 40-residue region that is conserved among a subset of site specific recombinase (integrase family).

Effects of endotoxin and neutrophil lysate on experimental otitis media with effusion in cats

Middle ear effusion (MEE) from otitis media with effusion (OME) contains large amounts of chemical mediators and substances from bacteria, which may act on the mucosa itself and cause further changes in the inflamed mucosa and MEE. To clarify the effects of such substances in MEE, we instilled endotoxin (LPS) or allogeneic neutrophil lysate (NL) into the middle ear cavity of OME induced by Eustachian tube obstruction (ETO). ETO + LPS and ETO + NL groups showed retention of a large amount of MEE as a characteristic difference between ETO alone group and these groups. The instillation of LPS into the middle ear cavity of the ETO model significantly increased the number of total cells and the ratio of the concentrations of albumin to total protein in MEEs. The instillation of NL significantly increased the number of goblet cells in the middle ear. These facts indicate that the pathology of OME may change in response to various factors added to MEE. Hence, we propose that a vicious circle of self-mediated inflammation is a possible causative factor for chronic OME.