Predicting anterior cruciate ligament degeneration using magnetic resonance imaging: Insights from histological evaluation

BACKGROUND

Mucoid degeneration of the anterior cruciate ligament is a pathological condition that may impair knee mechanics and contribute to the symptomatology of osteoarthritis. This study aimed to evaluate whether preoperative magnetic resonance imaging can predict anterior cruciate ligament degeneration, specifically mucoid degeneration, and to elucidate the histopathological characteristics of mucoid degeneration in knee osteoarthritis patients.

METHODS

We evaluated a total of 95 knees of osteoarthritis patients (23 males, 72 females; mean age: 72.7 ± 7.5) scheduled for total knee arthroplasty. The relationship between preoperative magnetic resonance imaging findings and the histopathological evidence of anterior cruciate ligament mucoid degeneration was examined. Immunohistochemical analysis was employed for collagen types (COL-I, COL-II), chondrogenesis (SOX9), and vascularity (CD31).

RESULTS

High signal intensity on magnetic resonance imaging showed a positive correlation with Alcian Blue staining areas (rs = 0.59, p < 0.01) and the swelling index (rs = 0.62, p < 0.01), indicating advanced mucoid degeneration. The absence of synovial lining around the anterior cruciate ligament was associated with more severe degeneration. In the histological evaluations, advanced degeneration was characterized by an increase in chondroid metaplasia and collagen disorientation. The Alcian Blue and SOX9 correlation was positive (rs = 0.69, p < 0.01), but negative with COL-I (rs = -0.38, p = 0.03) and vascularity (CD31) (rs = -0.60, p < 0.01).

CONCLUSIONS

Preoperative magnetic resonance imaging is an effective tool in assessing the severity of anterior cruciate ligament degeneration; it influences surgical decisions. High signal intensity on magnetic resonance images denotes advanced mucoid degeneration. The absence of synovial lining around the anterior cruciate ligament is associated with more severe degeneration and may accelerate degenerative changes. Chondroid metaplasia and collagen disorientation mark advanced degeneration. Magnetic resonance imaging can be used to gauge the degree of anterior cruciate ligament degeneration in osteoarthritis.

A case of methotrexate-related lymphoproliferative disease showing multiple liver lesions in a patient with rheumatoid arthritis

A 66-year-old woman with rheumatoid arthritis (RA) who had been receiving methotrexate (MTX) for 2 years presented with tarry stools. Contrast-enhanced computed tomography (CT) of the abdomen revealed irregular wall thickening in the ileocecal region and multiple low-contrast masses in both lobes of the liver. Lower gastrointestinal endoscopy revealed a type 2 tumor in the ileocecal region with a semi-peripheral ulcer. Histological examination of liver and colon biopsies showed other iatrogenic immunodeficiency-associated lymphoproliferative disorder (Oi-LPD), diffuse large B-cell lymphoma type, with positivity for Epstein-Barr virus DNA. After withdrawal of MTX, the LPD lesions disappeared and the patient achieved remission. We considered this to be a sporadic case of Oi-LPD, diffuse large B-cell lymphoma type, in the liver and colon due to treatment with MTX. There has been no previous report of this condition with simultaneous hepatic and colonic lesions, and the present case is thought to be highly informative in relation to the pathogenesis.

Neighboring macrophage-induced alteration in the phenotype of colorectal cancer cells in the tumor budding area

BACKGROUND

A higher number of tumor buds in the invasive front of colorectal cancer (CRC) specimens has been shown to contribute to a poor prognosis in CRC patients. Because macrophages (Mφs) have been demonstrated to alter the phenotype of cancer cells, we hypothesized that the phenotype of CRC cells in the tumor budding (TB) area might be changed by the interaction between CRC cells and Mφs.

METHODS

We assessed the expression of topoisomerase 1 in CRC cells to estimate the acquisition of chemoresistance in CRC. To demonstrate the tumor-stromal interaction between CRC cells and Mφs, we assessed two histological findings, the number of Mφs per single CRC cell and the proximity between CRC cells and Mφs by histological spatial analysis using HALO software.

RESULTS

The expression levels of topoisomerase 1 in CRC cells were decreased in deeper areas, especially in the TB area, compared to the surface area. Our histological spatial analysis revealed that 2.6 Mφs located within 60 μm of a single CRC cell were required to alter the phenotype of the CRC cell. Double-immunofluorescence staining revealed that higher Mφs were positive for interleukin-6 (IL-6) in the TB area and that AE1/AE3-positive CRC cells were also positive for phospho-STAT3 (pSTAT3) in the TB area; thus, the IL-6 receptor (IL-6R)/STAT3 signaling pathway in CRC cells was upregulated by IL-6 derived from neighboring Mφs.

CONCLUSION

IL-6 secreted from the neighboring Mφs would alter the phenotype of CRC cells via IL-6R/STAT3 signaling pathway.

Histological spatial analysis on the induction of PD-L1+ macrophages by CD8+ T cells at the marginal microenvironment of triple-negative breast cancer

BACKGROUND

Programmed death-ligand 1 (PD-L1) plays important roles in the evasion of antitumor immunity. Because we observed the localization of PD-L1-positive (PD-L1+) cells in the marginal region of triple-negative breast cancer (TNBC) specimens, we hypothesized that the marginal microenvironment of TNBC would involve the induction of PD-L1+ cells.

METHODS

One hundred and one TNBC surgical specimens were examined. We performed immunohistochemical (IHC) studies of PD-L1, CD68, CD8, and pan-cytokeratin in these specimens. We analyzed the localization of IHC-positive cells and the distance between these cells by histological spatial analysis.

RESULTS

In 30.7% of TNBC specimens, PD-L1+ cells were located in the marginal region. Approximately three PD-L1+ cells accumulated around a single TNBC cell. Most PD-L1+ cells were located within 50 μm of TNBC cells. PD-L1+ cells were indicated to interact with TNBC cells in the marginal region. PD-L1+CD68+ cells were located in the marginal region, while CD68+ macrophages (MΦs) were observed either in the marginal region or the core region. PD-L1 expression in MΦs was induced in the marginal region. The colocalization of CD8+ T cells in the marginal region indicates that PD-L1 expression in MΦs would be induced by interaction with CD8+ T cells. Because CD8+ T cells are positive for CCL2, CCL2 may induce PD-L1 expression in MΦs.

CONCLUSION

At the marginal microenvironment of TNBC, PD-L1 expression would be induced in MΦs by interaction with CD8+ T cells through CCL2. The interaction between PD-L1+ MΦs and TNBC cells would facilitate the growth of TNBC under antitumor immunity. These interactions would be potential targets for restoring antitumor immunity and suppressing TNBC progression.

Clinicopathological diversity of semantic dementia: Comparisons of patients with early-onset versus late-onset, left-sided versus right-sided temporal atrophy, and TDP-type A versus type C pathology

Semantic dementia (SD) is a unique clinicopathological entity associated with TDP-type C pathology. We present four cases of SD that illustrate the clinicopathological diversity of TDP-43 pathology, including early-onset cases of TDP-type C with corticospinal tract (CST) and motor neuron pathology and late-onset cases of TDP-type A with combined pathology. Case 1 was a 62-year-old man with semantic variant of primary progressive aphasia (svPPA) with left-predominant temporal atrophy and TDP-type C pathology with low Alzheimer's disease neuropathologic changes (ADNC). Case 2 was a 63-year-old woman with right-predominant temporal atrophy and TDP-type C pathology who had prosopagnosia and personality changes. Phosphorylated(p)-TDP-43-positive long dystrophic neurites (DNs) were observed throughout the cerebral cortex; they were more abundant in the relatively spared cortices and less so in the severely degenerated cortices. We observed CST degeneration with TDP-43 pathology in the upper and lower motor neurons, without apparent motor symptoms, in SD with TDP-type C pathology. Case 3 was a 76-year-old man who had svPPA and personality changes, with left-predominant temporal atrophy and TDP-type A pathology with high ADNC and argyrophilic grain (AG) stage 3. Case 4 was an 82-year-old man who had prosopagnosia and later developed symptoms of dementia with Lewy bodies (DLB) with right-predominant temporal atrophy and TDP-type A pathology with high ADNC, DLB of diffuse neocortical type, and AG stage 3. The distribution of p-TDP-43-positive NCIs and short DNs was localized in the anterior and inferior temporal cortices. An inverse relationship between the extent of TDP pathology and neuronal loss was also observed in SD with TDP-type A pathology. In contrast, the extent of AD, DLB, and AG pathology was greater in severely degenerated regions. CST degeneration was either absent or very mild in SD with TDP-type A. Understanding the clinicopathological diversity of SD will help improve its diagnosis and treatment.

GATA-3 is a proto-oncogene in T-cell lymphoproliferative neoplasms

Neoplasms originating from thymic T-cell progenitors and post-thymic mature T-cell subsets account for a minority of lymphoproliferative neoplasms. These T-cell derived neoplasms, while molecularly and genetically heterogeneous, exploit transcription factors and signaling pathways that are critically important in normal T-cell biology, including those implicated in antigen-, costimulatory-, and cytokine-receptor signaling. The transcription factor GATA-3 regulates the growth and proliferation of both immature and mature T cells and has recently been implicated in T-cell neoplasms, including the most common mature T-cell lymphoma observed in much of the Western world. Here we show that GATA-3 is a proto-oncogene across the spectrum of T-cell neoplasms, including those derived from T-cell progenitors and their mature progeny, and further define the transcriptional programs that are GATA-3 dependent, which include therapeutically targetable gene products. The discovery that p300-dependent acetylation regulates GATA-3 mediated transcription by attenuating DNA binding has novel therapeutic implications. As most patients afflicted with GATA-3 driven T-cell neoplasms will succumb to their disease within a few years of diagnosis, these findings suggest opportunities to improve outcomes for these patients.

Utility of Liquid-Based Cytology and Cell Block Procedure Obtained by Vitrectomy to Diagnose Ocular Sarcoidosis-The Significance of Epithelioid Granuloma and Epithelioid Cells

PURPOSE

The eyes are one of the most frequently involved organs in sarcoidosis in Asia, including Japan. Sarcoid uveitis is the major complaint of ocular sarcoidosis. The detection of epithelioid granuloma (EG) requires histological biopsy of the uvea for the precise diagnosis of sarcoid uveitis, because it is challenging to diagnose sarcoid uveitis without a history of systemic sarcoidosis. To diagnose sarcoid uveitis, we have established novel methods.

PATIENTS AND METHODS

In this study, we included 30 eyes of 21 patients with granulomatous uveitis diagnosed via slit-lamp examinations, gonioscopy, fundus photography, and fluorescein angiography. Vitrectomy was performed to remove the vitreous opacity with vision loss. To examine vitreous cell components, we used liquid-based cytology (LBC). To detect EG in an intraocular irrigating solution, we collected vitreous cell components, and then the cell pellets were embedded in the cell block procedure.

RESULTS

Here, we demonstrated the usefulness of the histological detection of EG and epithelioid cells (ECs) in LBC from vitreous body specimens and in the cell block procedure from vitreous cell components in an intraocular irrigating solution. Our results showed that the detection rates of EG were 6.3% (1/16) in LBC and 9.1% (1/11) in the cell block procedure in the sarcoid uveitis-suspected group and 7.7% (1/13) in LBC and 28.6% (2/7) in the cell block procedure in the sarcoidosis group. We would discuss the specificity of the EG/EC detection of ocular sarcoidosis.

CONCLUSION

Our methods are helpful in the precise diagnosis of ocular sarcoidosis and the control of the development of systemic sarcoidosis.

Successful treatment of acute pancreatitis associated with late-onset acute liver GVHD after second allogeneic hematopoietic cell transplantation

We report the case of a 28-year-old woman who developed upper abdominal pain and jaundice after a second unrelated allogeneic hematopoietic cell transplantation (allo-HCT) for acute lymphoid leukemia (ALL). Laboratory data showed elevated levels of liver enzymes, amylase, and lipase. Although acute pancreatitis was suspected, no structural lesions were detected. Liver biopsy was compatible with late-onset acute graft-versus-host disease (GVHD), which resolved following treatment with methylprednisolone (mPSL) and tacrolimus (TAC). In addition, her serum amylase level and abdominal pain rapidly resolved following acute GVHD-directed therapy. Acute pancreatitis concomitant with late-onset acute liver GVHD is extremely rare and has not been documented subsequent to a second allo-HCT.

Pathogenesis of follicular thymic hyperplasia associated with rheumatoid arthritis

Lymphoproliferative disorders may occur in patients with rheumatoid arthritis (RA) who are treated with methotrexate. However, follicular thymic hyperplasia (FTH) associated with RA (FTH‐RA) is generally not considered a lymphoproliferative disorder. To investigate the pathogenesis of FTH‐RA, we examined 12 cases of FTH involving thymic enlargement, four of FTH involving RA and eight of FTH involving myasthenia gravis (MG). Increased numbers and larger germinal center (GC) size were observed in FTH‐RA group. The percentage of distorted GCs was 13.3% in FTH‐RA group and 3.25% in FTH associated with MG (FTH‐MG) group. A greater meshwork of follicular dendritic cells was observed in the GCs of FTH‐RA group. Positive indices of CD27⁺ cells and PD‐1⁺ cells per GC in FTH‐RA group were significantly higher than those in FTH‐MG group, though positive indices of CD68⁺ cells and CD163⁺ cells were similar. Myoid cell proliferation, as evaluated by α‐SMA, tenascin‐C, and l‐caldesmon expression, was significantly increased in the FTH‐RA group compared with the FTH‐MG group. These results suggest that FTH should be considered in patients with RA treated with methotrexate. The pathogenesis of FTH‐RA includes GC expansion and increased numbers of memory B cells, follicular helper T cells, and myoid cells, indicating humoral immunity activation.

Malignant Progression of an IDH Mutant Brainstem Glioma in Adult

Brain stem gliomas (BSG) in adults are rare and less aggressive than those in children. However, the molecular profile of adult BSG cases has not been well characterized. We report a case of adult BSG with isocitrate dehydrogenase (IDH) mutation. A 43-year-old male was admitted to our hospital with diplopia and right-sided hypesthesia. An open biopsy led to the tumor being diagnosed as a diffuse astrocytoma. Immunohistochemically, the tumor was positive for IDH1 R132H, but negative for H3K27M. The patient received 54 Gy of local radiotherapy and adjuvant temozolomide, which resulted in the size of the lesion decreasing significantly. At 56 months after the initial diagnosis, the patient was referred to our hospital with a severe headache and ataxia. Magnetic resonance imaging (MRI) revealed a contrast-enhanced lesion in the brain stem, which extended into the left cerebellar hemisphere and brainstem. Partial tumor removal was performed, and a pathological examination revealed the features of glioblastoma. Immunohistochemically, the tumor was positive for IDH1 R132H and p53 and negative for ATRX. To the best of our knowledge, there are few reports about adult case of brain stem astrocytoma to be confirmed via histological and molecular examinations of the primary and recurrent tumor. We exhibit detailed pathological and molecular findings which resembles to IDH mutant supratentorial diffuse astrocytic tumors.

Clinicopathological heterogeneity of Alzheimer's disease with pure Alzheimer's disease pathology: Cases associated with dementia with Lewy bodies, very early-onset dementia, and primary progressive aphasia

We report four cases depicting the heterogeneity of Alzheimer's disease (AD) associated with pure AD pathology. Case 1 was a 77-year-old man with a false positive diagnosis of dementia with Lewy bodies with reduced dopamine transporter uptake activity of the striatum but no Lewy body pathology. There were tau deposits in the large neurons in the putamen, which may be related to the development of parkinsonism. Case 2 was an AD patient in his early 30s who presented with a psychotic episode and a cognitive decline, and later developed myoclonus and seizures. He demonstrated considerable amyloid-beta deposits in the cerebral cortex, including cotton wool plaques, basal ganglia, and cerebellum. Tau deposits were also abundant in the cerebral neocortex, hippocampus, basal ganglia, and brain stem. Case 3 was a 60-year-old woman who exhibited typical symptoms characteristic of the logopenic variant of primary progressive aphasia (lvPPA). Case 4 was a 68-year-old man who exhibited the semantic variant of primary progressive aphasia (svPPA) plus repetition impairment, a rare case associated with AD pathology. In addition to tau pathology, astrocytic pathology was prominent in the white matter and cortical layers of the left temporoparietal cortices. While the main AD lesion in case 4 was evaluated by tau accumulation and astrogliosis in the left temporal lobe, that in case 3 in was evaluated by the same points in the left parietal lobe. Within the spectrum of lvPPA, case 4 may be regarded as a temporal variant of lvPPA presenting svPPA. The pathology of PPA associated with AD may have broader clinical manifestations than that in previously described cases. Case 4 also showed pathological features characteristic of cerebral amyloid angiopathy throughout the cerebral cortex. The distribution of tau and astrocytic pathologies in the cerebral cortex, basal ganglia, brain stem, and cerebellum may explain the various symptoms of atypical pure AD patients.

Increasing Heme Oxygenase-1-Expressing Macrophages Indicates a Tendency of Poor Prognosis in Advanced Colorectal Cancer

BACKGROUND

Many cancers express heme oxygenase-1 -(HO-1) at a higher frequency than healthy tissues, and this elevated expression is associated with cancer prognosis. Here, we aim to clarify the correlation between HO-1-expressing macrophage numbers and clinicopathological parameters of advanced colorectal cancer.

MATERIALS AND METHODS

Formalin-fixed and paraffin-embedded tissues of patients with advanced colorectal cancer were used. To detect HO-1 expression in macrophages, immunohistochemistry was performed. The number of positive cells was measured. Furthermore, HO-1 mRNA in colorectal cancer was examined by reverse transcription polymerase chain reaction.

RESULTS

Among the HO-1-negative and HO-1-positive groups, 58.02 and 85.00% of cases, respectively, were positive for lymph node metastasis. The disease-free survival (DFS) time was significantly shorter (p < 0.05) in the -HO-1-positive group (2.44 years) than in the HO-1-negative group (4.09 years). However, according to the Cox proportional-hazards regression model, the HO-1-positive group could not be a risk factor of poor prognosis. HO-1 mRNA expression was confirmed in colorectal normal and cancer tissues.

CONCLUSION

In this study, the correlation between HO-1-expressing macrophages and clinicopathological parameters in the tumor microenvironment of colorectal cancer was studied for the first time, and the expression was associated with lymph node metastasis and shortening of DFS.

[Two-year remission of a relapsed primary gastric peripheral T-cell lymphoma treated with total gastrectomy followed by adjuvant chemotherapy]

A 67-year-old man was diagnosed with a submucosal primary gastric T-cell lymphoma (PGTL) via upper gastroenteroscopy following an annual health check-up. He received six cycles of CHOP and achieved a complete remission. However, the patient relapsed 4 months post therapy. A second remission, which was maintained for years, was achieved after surgical gastrectomy followed by adjuvant chemotherapies. Prior reports have shown that surgery combined with chemotherapies was curative for patients with newly-diagnosed PGTL. In this report, surgery combined with chemotherapies was successfully applied for early-relapsed PGTL.

Nodal histiocytic sarcoma with prominent eosinophilic infiltration: expression of eotaxin-2 on tumor cells

Background

Histiocytic sarcoma (HS) is a rare neoplasm showing morphological and immunophenotypic features of mature tissue histiocytes. We report a patient with nodal HS exhibiting prominent reactive eosinophilic infiltration.

Case presentation

A 68-year-old man presented with intermittent left lower abdominal pain and weight loss over 3 months. A computed tomography scan revealed multiple abdominal nodules. Open biopsy of the mesenteric tumors was performed for definitive diagnosis. Histologically, the tumor was comprised of a diffuse noncohesive proliferation of pleomorphic large cells, including multinucleated cells. Neoplastic cells were positive for histiocytic markers (CD68, CD163, and LIGHT) and PD-L1 but lacked markers of Langerhans cells, follicular dendritic cells, and epithelial cells. Frequent reactive inflammatory cells were intermingled in the background. Interestingly, prominent eosinophilic infiltration was also noted. Spindle neoplastic cells were prone to be present around areas with little to no eosinophilic infiltration and exhibiting fibrosis and lymphatic vessel proliferation. Conversely, polygonal neoplastic cells were prone to be present around areas with relatively large amounts of eosinophilic infiltration without fibrosis or lymphatic vessel proliferation. Immunohistochemically, the tumor cells and reactive eosinophils expressed eotaxin-2 and eotaxin-3, respectively.

Conclusion

We revealed that eotaxins induced the selective migration of eosinophils into tissues in this case. These eosinophils may affect the tumor remodeling and tumor biology characteristics of HS, such as fibrosis and lymphatic vessel proliferation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13000-020-01061-4.

Other Iatrogenic Immunodeficiency-Associated Lymphoproliferative Disorders, Diffuse Large B-Cell Lymphoma Type, in a Patient with Behçet's Disease Treated with Cyclosporine A

A 40-year-old man had been treated for Behçet's disease (BD) with cyclosporine A (CsA) for 14 years. He presented multiple lymphadenopathies with fever. Histological examination of surgical biopsy showed other iatrogenic immunodeficiency-associated lymphoproliferative disorders, diffuse large B-cell lymphoma type with positivity for Epstein-Barr virus encoding RNA-1 (EBER-1). BCL2-IgH, BCL6-IgH, and MYC-IgH translocations were not detected. CsA was stopped, and R-CHOP therapy was initiated. However, his lymphoma was chemotherapy resistant and rapidly progressed. To the best of our knowledge, this is the first case of diffuse large B-cell lymphoma that occurred in a BD patient treated with CsA reported in English. Both BD and CsA are associated with the pathogenesis of lymphoma. We also describe extremely rare cases in the form of a literature review.

Cytokeratin-positive interstitial reticulum cell (CIRC) tumor in the lymph node: a case report of the transformation from the epithelioid cell type to the spindle cell type

Background

Cytokeratin-positive interstitial reticulum cells (CIRCs), which are a subgroup of fibroblastic reticular cells (FRCs), are known to be present in the lymph nodes. There have been only a few cases of tumors derived from CIRCs.

Case presentation

We have reported a new case involving a CIRC tumor in a 75-year-old man and reviewed the literature. The resected mediastinal lymph nodes showed epithelial-like proliferation of large atypical round and polygonal epithelioid cells. The tumor cells expressed CK8, CK18, CAM5.2, AE1/AE3, epithelial membrane antigen, vimentin, fascin, and some FRC markers, which is consistent with the diagnosis of a CIRC tumor. Following chemotherapy, the CIRC tumor was observed to have responded very well and became difficult to confirm on imaging, but a small cell lung carcinoma developed 12 months later. Chemoradiotherapy was performed, but the patient passed away 29 months after the initial diagnosis. The autopsy revealed the recurrence of the CIRC tumor, residual small cell lung carcinoma, and a very small latent carcinoma of the prostate. The relapsed CIRC tumor cells had a spindle shape; they were highly pleomorphic and had invaded the superior vena cava.

Conclusion

We first reported autopsy findings of CIRC tumors and demonstrated the transformation of the tumor from the epithelioid cell type to the spindle cell type.

TERT promoter mutation associated with multifocal phenotype and poor prognosis in patients with IDH wild-type glioblastoma

Background

Although mutations in the promoter region of the telomerase reverse transcriptase (TERTp) gene are the most common alterations in glioblastoma (GBM), their clinical significance remains unclear. Therefore, we investigated the impact of TERTp status on patient outcome and clinicopathological features in patients with GBM over a long period of follow-up.

Methods

We retrospectively analyzed 153 cases of GBM. Six patients with isocitrate dehydrogenase 1 (IDH1) or H3F3A gene mutations were excluded from this study. Among the 147 cases of IDH wild-type GBM, 92 (62.6%) had the TERTp mutation. Clinical, immunohistochemical, and genetic factors (BRAF, TP53 gene mutation, CD133, ATRX expression, O⁶-methylguanine-DNA methyltransferase [MGMT] promoter methylation) and copy number alterations (CNAs) were investigated.

Results

GBM patients with the TERTp mutation were older at first diagnosis versus those with TERTp wild type (66.0 vs. 60.0 years, respectively, P = .034), and had shorter progression-free survival (7 vs. 10 months, respectively, P = .015) and overall survival (16 vs. 24 months, respectively, P = .017). Notably, magnetic resonance imaging performed showed that TERTp-mutant GBM was strongly associated with multifocal/distant lesions (P = .004). According to the CNA analysis, TERTp mutations were positively correlated with EGFR amp/gain, CDKN2A deletion, and PTEN deletion; however, these mutations were negatively correlated with PDGFR amp/gain, CDK4 gain, and TP53 deletion.

Conclusions

TERTp mutations were strongly correlated with multifocal/distant lesions and poor prognosis in patients with IDH wild-type GBM. Less aggressive GBM with TERTp wild type may be a distinct clinical and molecular subtype of IDH wild-type GBM.

The distribution of macrophage subtypes and their relationship to bone morphogenetic protein 2 in calcified aortic valve stenosis

Activation of the osteogenic signaling cascade (OSC) is thought to be involved in aortic valve stenosis. The aim of this study was to clarify the distribution of macrophage (M) subtypes in the calcified aortic valve and to clarify the relationship between osteoblast-like cells (OLC) and OSC activation. Thirty-six cases of calcified aortic valve were set as the calcification group, and six autopsy cases of aortic valve without pathological calcification comprised the noncalcification group. Aortic valve tissues were used in histological studies including single and double immunostaining to identify M subtypes, bone morphogenetic protein 2 (BMP2) and osteopontin, reverse transcription polymerase chain reaction (RT-PCR) for CD206, heme oxygenase-1 (HO-1), and BMP2 mRNAs and in situ RT-PCR for BMP2 mRNA. Ms positive for CD68, CD163, CD206, and HO-1 were significantly higher in the calcification group than in the noncalcification group (P < 0.01). Comparison of the positive cells in each section of the calcification group showed that cells of all M subtypes were found around calcifications. Osteopontin⁺ cells were also observed around calcifications. CD163⁺/CD206⁺ M2 and CD163⁺/HO-1⁺ Mox were significantly higher in the sponge layer in both groups. In double immunofluorescence, CD206⁺ and a portion of HO-1⁺ Ms expressed BMP2, and in RT-PCR, CD206 or HO-1 mRNA was expressed in cases in which BMP2 was expressed. In in situ RT-PCR, expression of BMP2 mRNA was observed around calcifications. This work clarifies the distribution of M subtypes in calcified aortic valves. In addition, the results suggest that CD206⁺ M2 and HO-1⁺ Mox, which express BMP2 in calcified aortic valves, are OLC candidates.

Good prognosis for follicular lymphoma with estrogen receptor α-positive follicular dendritic cells

Follicular lymphoma (FL) has a meshwork of follicular dendritic cells (FDCs). We previously demonstrated the presence of estrogen receptor alpha (ERα)⁺CD23⁺ FDCs in grades 1‐2 FL. The significance of FDCs as a prognostic factor in FL remains unknown. The current study aimed to compare clinicopathological features, including prognosis, between FL with and without ERα⁺ FDCs. This study evaluated the clinicopathological significance of ERα expression in 70 FL patients by immunostaining. The presence of ERα mRNA on FDCs from 5 FL patients was confirmed by CD21/ERα double staining (immunohistochemistry and in situ hybridization). We defined patients with frequent ERα expression as the ERα^high group and those with infrequent ERα expression as the ERα^low group. Thirty‐two patients were assigned to the ERα^high group (45.7%), and 38 patients were assigned to the ERα^low group (54.3%). Both overall survival (OS) and progression‐free survival (PFS) were significantly better in the ERα^high group than in the ERα^low group (OS, log‐rank, P = .0465; PFS, log‐rank, P = .0336). Moreover, high ERα expression on FDCs was an independent prognostic factor for OS in both the univariate ([hazard ratio] HR, 0.163; P = .0260) and multivariate (HR, 0.050; P = .0188) analyses and for PFS in both the univariate (HR, 0.232; P = .0213) and multivariate (HR, 0.084; P = .0243) analyses. ERα mRNA expression was detected in CD21⁺ FDCs within the neoplastic follicles of FL patients. In conclusion, a neoplastic follicular microenvironment with ERα‐positive FDCs might affect the grade and presence of the follicular pattern of FL and improve patient prognosis.

A case of iatrogenic immunodeficiency-associated colonic lymphoma complicating ulcerative colitis

Background

Ulcerative colitis (UC) is one of the major types of inflammatory bowel diseases and is associated with a significantly increased risk of not only lymphoproliferative disorders but also lymphomas, of which most cases are related to the long-term usage of immunosuppressants. Here, we demonstrate a very rare case of other iatrogenic immunodeficiency-associated colonic diffuse large B-cell lymphoma (Oii-DLBCL) complicating UC and rectal perforation. In addition, we reviewed the clinicopathological features of previous cases of DLBCL related to UC.

Case presentation

A 68-year-old man was diagnosed with left-sided UC 26 months prior. Although he was followed by immunosuppressive therapy with azathioprine and infliximab, an emergency total proctocolectomy was performed due to rectal perforation. The resected specimen exhibited irregular wall thickening and elevated multinodular lesions extending from the mid-transverse colon to the rectum, measuring up to 52 cm in length. Histologically, the lesion was diagnosed as Oii-DLBCL and crypt abscess surrounded by mixed inflammatory cell was remained.

Conclusion

Oii-DLBCL complicating UC with rectal perforation is extremely rare. Macro- and microscopic findings are important for early diagnosis of the lesion.

Comparative study of HO-1 expressing synovial lining cells between RA and OA

OBJECTIVES

We aimed to clarify the characteristics of heme oxygenase (HO)-1 expressing cells in the synovium from rheumatoid arthritis (RA) and osteoarthritis (OA), and to investigate the co-expression of HO-1 and IgG-Fc/HLA-DR complex.

METHODS

The characteristics of HO-1 expressing cells in the synovium were investigated by using immunohistochemistry. The co-expression of HO-1 and IgG-Fc/HLA-DR complex was examined by an in situ proximity ligation assay (PLA) with immunofluorescence. HO-1 mRNA was investigated by reverse transcription-polymerase chain reaction.

RESULTS

The number of HO-1⁺ cells from the RA synovium is higher than that from OA synovium. The double positive cells of HO-1 and IgG-Fc/HLA-DR complex were detected by the in situ PLA with immunofluorescence in RA synovium. HO-1 mRNA was detected in both RA and OA synovium.

CONCLUSION

A portion of HO-1⁺ cells with IgG-Fc/HLA-DR complex in lining layer of RA may be concluded as one of antigen presenting cells in RA and may be involved in production of RF.

Rapid Progression of Intracranial Dural Metastases in a Patient with Carcinoma of Unknown Primary Site

Dural metastases are uncommon in cancer patients, but can have as much of an effect on the lives of patients as brain metastases. Dural metastases are most commonly associated with primary cancers of the breast, prostate, and lung, and it is rare that the primary site of the tumor is unknown. In this study, we encountered a 51-year-old woman who had developed multiple bone tumors, with no known primary cancer lesion. A tumor biopsy of the sacral bone revealed non-keratinizing squamous cell carcinoma; the patient was therefore diagnosed as having multiple bone metastases of an unknown primary cancer. Magnetic resonance imaging revealed cranial metastases and partial thickening of the dura with suspected dura metastases. Platinum-based chemotherapy reduced the bone metastases and the thickened dura. However, as resistance to chemotherapy developed, invasions progressed rapidly and diffusely throughout the dura. This was accompanied by the development of dysarthria, visual impairments, and delirium. The patient died 10 months after being diagnosed with dural metastases. This report provides information on the clinical course and prognosis of patients with dural metastases of unknown primary cancer. Furthermore, it may help to construct a treatment strategy for dural metastases.

Diagnostic utility of CD205 in breast cancer: Simultaneous detection of myoepithelial cells and dendritic cells in breast tissue by CD205

BACKGROUND

CD205 can be used to detect myoepithelial cells (MECs) and dendritic cells (DCs) in breast tissue. However, the usefulness of CD205 immunostaining in the pathological diagnosis of breast tumors is not fully understood. The objective of this study was to re-evaluate CD205 co-expression with other MEC markers, such as p63 and CD10, in nonneoplastic and neoplastic breast tissue and to evaluate its pathological diagnostic utility in these types of breast cancer.

MATERIAL AND METHODS

Nonneoplastic breast tissue samples with a terminal duct lobular unit and duct were obtained from fibroadenoma and mastopathy patients. Neoplastic breast tissue samples included ductal carcinoma in situ (DCIS) (n=43) and invasive ductal carcinoma (IDC) (n=60), including the tubule-forming type (n=20). These specimens were investigated by CD205, p63, and CD10 immunostaining.

RESULTS

In addition to p63 and CD10, CD205 was expressed on MECs in nonneoplastic breast and DCIS tissue samples; CD205 was simultaneously detected on DCs that had infiltrated DCIS and IDC tumor nests. CD205 was expressed on cancer cells themselves in only 7.3% of the breast cancer samples. The number of intratumoral CD205⁺ DCs in tubular IDC was significantly higher than that in DCIS (P<0.01).

CONCLUSION

Because CD205 was simultaneously detected on MECs and DCs in the same breast tissue sections, it may be useful for distinguishing tubular IDC from DCIS.

Differential expression of estrogen receptor-α on follicular dendritic cells from patients with grade 1-2 and grade 3 follicular lymphoma

Hormone therapy has been used for patients with estrogen receptor alpha (ERα)–positive breast cancers. Recently, some studies reported the expression of ERα on neoplastic cells from B‐cell lymphomas. However, there has been only one report of ERα expression on the follicular dendritic cells (FDCs) that structurally and functionally support the microenvironment of follicular lymphomas (FLs). The objective of this study was to investigate the frequency of ERα expression on FDCs in nonneoplastic reactive lymphoid tissues and to compare the frequency of ERα expression on FDCs in the axillary lymph nodes between patients with and without antiestrogen therapy and among patients with grades 1‐3 of FL. Reverse transcription–polymerase chain reaction was performed to detect ERα mRNA in FL. In nonneoplastic germinal centers (GCs) from patients with tonsillitis or reactive lymphadenitis, ERα was expressed in the light zone. ERα‐positive cells strongly correlated with the width of GCs (r_s = 0.81, P < 0.01) and the CD21‐positive (r_s = 0.69, P < 0.01) and CD23‐positive (r_s = 0.83, P < 0.01) FDC meshwork. The axillary lymph nodes had fewer ERα‐positive cells, smaller GCs, and a looser CD21‐ and CD23‐positive FDC meshwork with hormone therapy than without hormone therapy (P < 0.01). Neoplastic follicles of G1‐2 FL had more ERα‐positive cells and a larger CD23⁺ FDC meshwork than those of G3 FL (P < 0.01). ERα mRNA was detected in both G1‐2 FL and G3 FL by reverse transcription–polymerase chain reaction. In conclusion, these results suggested that antiestrogen hormone therapy may decrease the number of ERα‐positive FDCs and that the responses mediated by the estrogen‐ERα interaction on FDCs may differ between G1‐2 FL and G3 FL.

Expression of TRPM8 in human reactive lymphoid tissues and mature B-cell neoplasms

Transient receptor potential melastatin 8 (TRPM8) is a member of the transient receptor potential superfamily of Ca²⁺ channels. The aim of the present study was to clarify TRPM8 expression in reactive lymphoid tissues and mature B-cell neoplasms. Reactive and neoplastic lymphoid tissues were used to evaluate TRPM8 expression by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). TRPM8⁺ cells were frequently detected in the follicular light zone and marginal zone of reactive lymphoid tissues. Double immunostaining revealed that TRPM8⁺ cells co-expressed cluster of differentiation (CD) 38, CD79a, CD138, interferon regulatory factor 4/melanoma associated antigen (mutated) 1, B cell CLL/lymphoma 6 and transmembrane activator and CAML interactor. TRPM8⁺ neoplastic cells were frequently detected in plasma cell myeloma. The positive band of TRPM8 mRNA was confirmed by RT-PCR in cases of myeloma. The present study is, to the best of our knowledge, the first to demonstrate the expression of TRPM8 in reactive lymphoid tissues and mature B-cell neoplasms, revealing that TRPM8 is frequently expressed in pre-plasmablasts, plasmablasts, plasma cells and mature B-cell lymphomas that are likely to differentiate into plasma cells.

Poorly differentiated ductal adenocarcinoma of the pancreas with rapid progression in a young man

Pancreatic cancer in young adults is very rare. We report a case of young-onset poorly differentiated pancreatic ductal adenocarcinoma with rapid progression and poor prognosis in a 31-year-old Japanese man with no obvious family history of malignancy. Preoperative examinations revealed a mass lesion in the body of the pancreas, accompanied by a slightly dilated main pancreatic duct distal to the mass lesion. Pancreatic cancer with acute pancreatitis was suspected because of an elevation of serum pancreatic enzyme and tumor marker, along with imaging findings. Distal pancreatectomy with resection of the common hepatic artery and splenectomy along with lymph node dissection was performed. Microscopically, the tumor was mainly composed of poorly differentiated ductal adenocarcinoma. The postoperative course was uneventful, but the patient had multiple liver metastases 2 months postoperatively, in spite of adjuvant chemotherapy, and died 8 months postoperatively. This case may represent a rare instance of young-onset poorly differentiated ductal adenocarcinoma with rapid progression and may indicate potential risk factors of pancreatic cancer in young adults.

Detection of Minimal Bone Marrow involvement of Blastic Plasmacytoid Dendritic Cell Neoplastic Cells - CD303 immunostaining as a diagnostic tool

Blastic plasmacytoid dendritic cell (pDC) neoplasm (BPDCN) is a relatively rare hematological malignancy with significantly complex clinicopathological features that are still unclear. This study aimed to analyze the clinicopathological data of BPDCN and evaluate immunohistochemical detection of minimal bone marrow (BM) involvement. In this study, we examined skin and BM lesions from 6 patients with BPDCN. Neoplastic cells tested positive for CD303 (polyclonal, 100%; monoclonal, 40%) in the skin lesions and for CD303 (polyclonal, 100%; monoclonal, 67%) in the BM clots. Although immunostaining of CD4, CD56, CD123, CD303, and TCLl detected minimal BM involvement in 3 patients, morphological identification was challenging in the BM clots stained with hematoxylin-eosin. In conclusion, our results demonstrate the significance of observing BM smears to detect neoplastic cells and that immunohistochemical examination, including CD303 antibodies, is useful to detect minimal BM involvement. This study is the first to report the expression of thymic stromal lymphopoietin (TSLP) and its receptor in BPDCN cells. Therefore, the TSLP/TSLP receptor axis may be associated with the proliferation of BPDCN, and consequently, the survival of patients.

Immunoglobulin G Subclass 4-Related Lymphoplasmacytic Thoracic Aortitis in a Patient with Acute Type A Aortic Dissection

Immunoglobulin G subclass 4-related disease (IgG4-RD) is a recently recognized systemic inflammatory disease characterized by an elevated serum IgG4 level and an IgG4-positive lymphocyte infiltrate mainly in exocrine tissues. Previous reports documented IgG4-RD in several cardiovascular disorders. We present a case of type A aortic dissection associated with IgG4-RD. A 52-year-old man diagnosed with a type A aortic dissection was referred for surgical treatment. He underwent emergency hemiarch reconstruction with a prosthetic graft. His postoperative recovery was uncomplicated. Histopathologic examination of his aortic tissue showed marked adventitial thickening with fibrosis and an IgG4-positive plasma cell infiltrate. He was diagnosed with type A aortic dissection incidentally complicated by IgG4-RD. The relationship between IgG4-RD and the pathogenesis of aortic dissection remains unknown and requires further investigation.

Corneal vesicles accumulate collagen VI associated with tissue remodeling in apolipoprotein a-I deficiency: a case report

Background

Apo A-I deficiency clinically shows low serum levels of HDL cholesterol and corneal opacity at a young age. Histopathological evaluations of affected corneas are not enough, and the mechanism of corneal opacity is still unclear.

Case presentation

A 61-year-old woman suffered from blurred vision with a corneal opacity. She had significantly reduced serum levels of high-density lipoprotein cholesterol and Apo A-I, stenosis of the coronary arteries, and ischemic heart failure. On genetic examination, a homozygous mutation of Apo A-I_Tsukuba was identified. Histopathological examination of the corneal button after PKP showed numerous vesicles in the corneal stroma, which were more prominent in the deep stroma than in the shallow stroma. Collagen VI was observed in some of those vesicles.

Conclusion

We experienced a rare case of corneal opacity due to Apo A-I deficiency. Our histopathological findings indicated that structural changes in corneal collagen fibrils contribute to the formation of stromal vesicles.

Specific Neuropilins Expression in Alveolar Macrophages among Tissue-Specific Macrophages

In the immune system, neuropilins (NRPs), including NRP-1 and NRP-2, are expressed in thymocytes, dendritic cells, regulatory T cells and macrophages. Their functions on immune cells around the neoplastic cells vary into pro-angiogenesis, tumor progression and anti-angiogenesis according to their ligands. Even though NRPs expression on malignant tumors and immune system has studied, a PubMed-based literature query did not yield any articles describing NRPs expression on tissue-specific macrophages. The aims of this study were (i) to detect NRPs expression on tissue-specific macrophages in the brain, liver, spleen, lymph node and lung; (ii) to observe NRPs expression in classes of macrophages, including alveolar macrophages (AMs), bronchial macrophages (BMs), interstitial macrophages (IMs), intravascular macrophages (IVMs) and macrophage subsets (M1, M2 and Mox) in lung; and (iii) to detect the co-expression of NRPs and dendritic cell-specific ICAM-3-grabbing nonintegrin (DC-SIGN) in AMs. Both NRPs were specifically detected in AMs among tissue-specific macrophages by immunohistochemistry (IHC). NRPs mRNA expression levels were characterized in normal lung by reverse transcriptase polymerase chain reaction (RT-PCR) and in situ-polymerase chain reaction (in situ-PCR). The expression of both NRPs was detected in AMs, BMs and IVMs by IHC. The frequency of NRPs⁺ AMs in lung tissue adjacent to the cancer margin was significantly higher than the frequencies in inflamed and normal lung tissue. Double and triple IHC demonstrated that NRPs are expressed on all macrophage subsets in lung. Double IHC showed co-expression of DC-SIGN and NRPs in AMs. This study demonstrated for the first time the specific expression of both NRPs in AMs among tissue-specific macrophages and their expression on M1, M2 and Mox macrophages. Furthermore, the possible origin of AMs from blood monocytes could be suggested from a co-expression of NRPs and DC-SIGN.

Localization of collagen modifying enzymes on fibroblastic reticular cells and follicular dendritic cells in non-neoplastic and neoplastic lymphoid tissues

The aim of this study was to evaluate the localization of collagen modifying enzymes (CMEs) on fibroblastic reticular cells (FRCs) and follicular dendritic cells (FDCs) in non-neoplastic lymphoid tissues and various malignant lymphomas. The expression of prolyl 4-hydroxylase 1 (P4H1), lysyl hydroxylase 3 (LH3), and protein disulfide isomerase (PDI) was frequently observed on FRCs and FDCs in the germinal center (GC), except for the mantle zone. The expression of CMEs was lower in most lymphomas than in their respective postulated normal counterparts. The ratio of transglutaminase II⁺ FRCs/CD35⁺ FDCs was also lower in follicular lymphomas (FL) than in other lymphomas. The mRNAs of some CMEs (P4H1, prolyl 4-hydroxylase 3, LH3, and heat shock protein 47) were confirmed in almost all lymphomas. These results indicate that lymphoma cell proliferation suppresses/decreases the number of CMEs expressing FRCs and FDCs in most lymphomas.

Immunoglobulin and CD8⁺ T-cell distribution in histologically distinctive tonsils of individuals with tonsillar focal infection

CONCLUSION

This study demonstrated that the common immunological mechanism, which involves aberration of immunoglobulin and T-cell distribution in histologically distinctive tonsils, may be associated with the pathogenesis of tonsillar focal infection.

OBJECTIVES

Tonsillar focal infection comprises a group of relatively common diseases combined with chronic tonsillar infection, is associated with unusual immune responses in tonsils, and may cause lesions in another distant target organ. This study aimed to investigate the distribution of inflammatory T cells and T-cell regulatory elements, such as programmed cell death-1 (PD-1) and Fork head box protein 3 (Foxp3), immunoglobulin production, and histological characteristics in tonsils from patients with tonsillar focal infection.

METHODS

Immunohistochemistry and reverse transcription-polymerase chain reaction (PCR) were used to compare the expression of CD8(+) T cells, immunoglobulins, and cytokines associated with immunoglobulin production in the tonsils of patients with IgA nephropathy (IgAN), palmoplantar pustulosis (PPP), rheumatoid arthritis (RA), and chronic tonsillitis.

RESULTS

The overexpression of CD8(+) T cells combined with decreased expression of Foxp3 and PD-1 and the aberration of immunoglobulin production, which may be due to the elevated expression of activation-induced deaminase (AID), B-cell-activating factor of the TNF family (BAFF), supporting isotype switching, and B-cell survival in the histologically distinctive tonsils.

An immune pathological and ultrastructural skin analysis for rhododenol-induced leukoderma patients

As reported in the mass media on July 2013, numerous consumers who had used the cosmetic ingredient containing rhododendrol (4-(4-hydroxyphenyl)-2-butanol, Trade name; rhododenol), which is a melanin inhibitor isolated from Acer nikoense Maxim, released from Kanebo Cosmetics Inc. (Tokyo, Japan) noticed leukoderma patches on their face, neck and hands. We have experienced 32 cases that developed leukoderma after using such cosmetics so far and skin biopsy samples in some cases were obtained from both leukoderma and pigmented lesions. A histopathological analysis for skin lesions obtained from such patients notably showed basal hypo-pigmentation, melanin incontinence, and remaining melanocytes in most patients which is not relevant in vitiligo vulgaris. Subsequently, we comprehensively carried out immunohistochemical analyses of immune-competent cells infiltration to assess the effect of the cellular immune response to inducible hypopigmentation. Furthermore, detailed morphological observations performed by electron-microscopy notably showed the presence of melanocytes with only a small number of melanosomes, dermal fibroblasts containing melanosome globules and melanophages whereas no damage associated with melanosome transfer and the basal layer apparatus. These findings provide a cue to diagnose as rhododenol-induced leukoderma differentiate from vitiligo vulgaris and for rhododendrol to induce local immunity in addition to melanocyte damage.

Contribution of corneal neovascularization to dendritic cell migration into the central area during human corneal infection

Compared with the peripheral corneal limbus, the human central cornea lacks blood vessels, which is responsible for its immunologically privileged status and high transparency. Dendritic cells (DCs) are present in the central avascular area of inflamed corneas, but the mechanisms of their migration to this location are poorly understood. Here, we investigated the contribution of vessel formation to DC migration into the central cornea, and analyzed the DC chemotactic factors produced by human corneal epithelial (HCE) cells. Using human eyes obtained from surgical procedures, we then assessed vessel formation, DC distribution, and activin A expression immunohistochemically. The results demonstrated increased numbers of vessels and DCs in the central area of inflamed corneas, and a positive correlation between the number of vessels and DCs. Activin A was expressed in the subepithelial space and the endothelium of newly formed blood vessels in the inflamed cornea. In infected corneas, DCs were present in the central area but no vascularization was observed, suggesting the presence of chemotactic factors that induced DC migration from the limbal vessels. To test this hypothesis, we assessed the migration of monocyte-derived DCs toward HCE cell supernatants with or without lipopolysaccharide (LPS) stimulation of HCE cells and inflammatory cytokines (released by HCE cells). DCs migrated toward tumor necrosis factor alpha (TNF-α), interleukin (IL)-6, and activin A, as well as LPS-stimulated HCE cell supernatants. The supernatant contained elevated TNF-α, IL-6, and activin A levels, suggesting that they were produced by HCE cells after LPS stimulation. Therefore, vessels in the central cornea might constitute a DC migration route, and activin A expressed in the endothelium of newly formed vessels might contribute to corneal vascularization. Activin A also functions as a chemotactic factor, similar to HCE-produced TNF-α and IL-6. These findings enhance our understanding of the pathophysiology of corneal inflammation during infection.

Myoepithelial carcinoma of the breast with focal rhabdoid features

Myoepithelial carcinoma of the breast is extremely rare and only 33 cases have been reported in the English literature. Herein, we report a case of myoepithelial carcinoma of the breast with focal rhabdoid features. The patient was a 67-year-old woman, who presented with a lump of the left breast that rapidly grew to 3 cm in diameter within 3 months. Lumpectomy revealed a solid and whitish colored tumor, which was composed mainly of elongated spindle-shaped cells with mild atypia, focal necrosis, and infiltrative margin. In a small area of the lesion, ovoid tumor cells exhibited eccentric nuclei with centrally located nucleoli and plump cytoplasm including round eosinophilic inclusions, resembling a rhabdoid tumor. Immunohistochemically, both types of tumor cells exhibited a myoepithelial phenotype. MIB-1 index was 30%. The cytoplasmic inclusion of the ovoid cells exhibited immunopositivity for both vimentin and cytokeratin. From these findings, this tumor was diagnosed as a myoepithelial carcinoma with focal rhabdoid features. Although rhabdoid features have been reported in some types of malignant and benign tumors, this is the first report of such features in myoepithelial carcinoma of the breast.

Angioimmunoblastic T-cell lymphoma with dual genotype of TCR and IgH genes

A 70-year-old man complained of fever and sore throat accompanied by hoarseness of voice. On physical examination, there was no systemic abnormality but a mild lymphadenopathy of cervical lymph nodes. With laryngoscopy, there was a marked outgrowth of the bilateral palatine tonsils proximal to the vocal cord. The histology of the resected tumor was compatible with angioimmunoblastic T cell lymphoma (AITL), revealing the effacement of normal tonsillar architecture and small to medium-sized neoplastic cell proliferation around marked vascular proliferation and atrophic lymphoid follicles. Tumor cells were positive for conventional T-cell antigens as well as for the follicular helper T-cell marker, PD-1, and CXCL13. Large hodgkinoid cells, but no tumor cells, were positive for latent membrane protein-1 and Epstein-Barr virus-encoded small RNA (EBER)-1 (in situ hybridization). Non-neoplastic, double positive cells for EBER-1 and CD20 were also scattered. Southern blot analysis revealed dual TCR-Cβ1 and IGH-JH gene rearrangements. Although the swelling of bilateral inguinal and perigastric lymph nodes developed later, the radical resection of tumor and chemotherapy appeared to be effective for the treatment of AITL with clinical stage IIIa. We here report a rare case of AITL involving palatine tonsil as primary site and give a review of the literature.

Isolation of Aino virus from an aborted bovine fetus

A male fetus of gestation day 187 was aborted from a Holstein-Friesian cow in an epizootic of the Aino virus (AINOV) in September 1995. Neutralizing antibody titers against AINOV were 1:128, 1:16 and 1:64 in the dam serum, fetal ascites and cerebrospinal fluid, respectively. A 10% brain suspension of the aborted fetus was prepared immediately after autopsy, rinsed three times and sonicated before centrifugation. The supernatant was then inoculated into HmLu-1 cell cultures. A cytopathic effect was noted on post-inoculation day 7. The isolated virus was identified as the AINOV based on the physicochemical properties and cross neutralization test. This is the first report on the isolation of AINOV from an aborted bovine fetus.

Aino virus antigen in brain lesions of a naturally aborted bovine fetus

A bovine fetus aborted at 187 days of gestation was serologically and immunohistopathologically examined. Serum and cerebrospinal fluid samples had high titers of virus-neutralizing antibody for Aino virus. A severe necrotizing encephalopathy was noted. Aino virus antigen was demonstrated in neuroglial cells within the brain lesion. The destruction of developing neuronal cells appeared to be a significant feature of the pathogenesis of lesions due to Aino virus infection in the central nervous system.

Immunohistochemical expression of microtubule-associated protein 5 (MAP5) in glial cells in multiple system atrophy

An immunohistochemical study focusing on glial cells was performed using monoclonal antibodies against microtubule-associated proteins (MAP1, MAP2 and MAP5), transferrin, leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) in 5 cases of multiple system atrophy (MSA) exhibiting olivopontocerebellar atrophy and striatonigral degeneration. An antibody to MAP5, a fetal antigen in developing brain, was strongly demonstrated in the glial cytoplasmic inclusions (GCIs) which have recently drawn a great deal of attention and were observed in all 5 cases of MSA. Moreover, MAP5-positive glial cells (MAP5-Gs) were present in significantly higher number than in the controls in various regions where GCIs were found, predominantly in putamen, substantia nigra, cerebellar white matter and internal capsule. LCA and transferrin, markers of microglia and oligodendroglia, respectively, were immunohistochemically detected in some MAP5-Gs. GFAP, on the other hand, was not expressed in MAP5-Gs at all. These findings suggest that MAP5-Gs consist of reactive microglia and oligodendroglia. Our study is the first to demonstrate immunohistochemical detection of MAP5 in glial pathological changes in MSA.

Abnormal molecules of mitochondrial aspartate aminotransferase in the liver of vitamin B-6--deficient rats may be produced in the mitochondrial matrix

The distribution of mitochondrial aspartate aminotransferase (AspATm) in liver cells was studied in rats fed pyridoxine-deficient and control diets. Mitochondrial aminotransferase activity was found mainly in the matrix fraction, with smaller amounts in the outer membranes, intermembrane space and cytosol. The precursor of the enzyme was detected in the liver cytosol of both vitamin B-6--deficient and control rats, and its amount was similar in the two groups. When pyridoxal phosphate was added to the assay system, the ratio of enzyme activity to antigenic activity (E/A) of mitochondrial aspartate aminotransferase in the cytosol of both vitamin B-6--deficient and control rats was about 70% of that in the matrix of control rats. On the other hand, the E/A of the matrix enzyme in deficient rats was 53% of that of controls. From these results we concluded that pyridoxal phosphate is not necessary for translocation of mitochondrial aspartate aminotransferase into mitochondrial matrix and that abnormal molecules of the enzyme may be formed in the matrix of vitamin B-6--deficient rat liver.