Immunohistological identification of the activated lymphocytes in human palatine tonsil

Employing various monoclonal antibodies and immunoperoxidase technique, we studied the distribution of the activated lymphocytes in human tonsillar tissue. Both the activated T-cells positive for IL2-receptor (IL2-R) and the activated B-cells defined by L29 were seen in the interfollicular area. Vast majority of the lymphocytes in the germinal center was stained with the L29, the anti-transferrin-receptor antibody, and the Ki-67 antibody which reacts with cycling cells in G1, S, or G2 + M phase. On the other hand, scarcely any cells in the mantle zone were stained with those. The Ki-67 positive cells in the germinal center were identified as two types of staining pattern, i.e., with strong nucleolar staining found in the dark zone and with nuclear staining found in the light zone. Small number of IL2-R positive cells was found in the mantle zone. The cell number per unit area of the activated lymphocytes in the interfollicular area as well as in the germinal center was decreased as the increment of patients' age. From these results, the immunological activation system of T- and B-cells in the tonsils was discussed.     

Genotypic analysis of lethal midline granuloma]

So-called lethal midline granuloma is of great clinical and theoretical interest. The etiology of lethal midline granuloma is unknown and the pathogenesis is variable, with debate as to precise classification and natural history. In this study, we reported genotypic and immunopathological features in 3 cases of lethal midline granuloma. The histopathological diagnosis of their biopsy specimens was initially polymorphic reticulosis/midline malignant reticulosis. Immunohistologic study of the specimens revealed that immature or atypical cells had phenotypes of T-cells, CD2, CD3, CD4 (Case 1), CD4 (Case 2), and CD2, CD3 (Case 3). Those cells were also found to be positive for HLA-DR, which indicated that they were activated T-cells. Immunohistology in T-cells, however, was not able to give a similar clue to clonarity as it was possible within B-cell neoplasms by immunophenotyping the light chains. With the establishment of cDNA probes for the T-cell receptor genes it was possible to analyze neoplasms of lymphocyte origin for lineage and clonality. The Southern blot analysis of 3 cases showed rearrangement of TCR gene, TCR beta and TCR gamma chain (Cases 1 and 2) and TCR beta and TCR delta chain (Case 3), whereas none of them showed rearrangement of immunoglobulin heavy chain. These findings represented conclusive evidence for a monoclonal T-cell proliferation within lethal midline granuloma. On the ground of immunohistological and genotypic studies, lethal midline granuloma histologically diagnosed as polymorphic reticulosis/midline malignant reticulosis are proven to be a T-cell lymphoproliferative disorder.     

Inhibition of Natural Killer Cell Cytotoxicity by Cell Growth-related Molecules

Certain MHC class I molecules on target cells are known to inhibit the cytotoxic action of NK cells. By using monoclonal antibody (mAb) Cho-1, we have found inhibitory non-MHC class I cell surface molecules that are noncovalently-associated with 200 kDa and 40 kDa antigens. Poly I-C-induced rat NK cells were not cytotoxic to rat fetus-derived fibroblast WFB cell line. In contrast, NK cells were cytotoxic to H- ras oncogene-induced transformants of WFB, W14 and W31. FACS analysis indicated that mAb Cho-1 reacts with WFB, but not with W14 and W31 cells. Thus, this antigen may disappear concomitantly with cell growth and transformation. Cho-1 antigens were also expressed on other NK-resistant lines, such as mouse BALB3T3 fibroblast, EL-4 lymphoma and human fibroblast HEPM. However, they were not expressed on NK-sensitive mouse YAC-1 and H- ras transformant (Brash) of BALB3T3 cells. Furthermore, treatment of target cells with IFN-γ clearly induced the cell surface expression of Cho-1 antigens, and conferred a resistance to NK cytolysis on target cells. These data strongly suggest that Cho-I antigen expression may correlate with target cell susceptibility to NK cells. Indeed, treatment of NK-resistant WFB as well as HEPM cells with F(ab')₂ fragments of mAb Cho-1 resulted in the acquisition of susceptibility to NK cytolysis. Cho-1 antigens may be novel molecules that regulate the NK resistance of cells.     

Assessing liver function by magnetic resonance imaging two-dimensional phase-shift flow measurement of portal venous blood flow after oral intake of glucose

We have already reported that the ratio of portal venous flow 30 min after oral intake of glucose 75 g to that before intake (PVFR30), measured using pulsed-Doppler ultrasonography (US), correlated significantly with other indicators of liver function and that it could be used to estimate hepatic function before surgery, including liver resection. In this study, to assess the disadvantages of pulsed-Doppler ultrasonography, PVFR30 was measured using two-dimensional (2D) phase-shift (PS) magnetic resonance imaging (MRI). PVFR30 was measured in 17 patients and 7 volunteers: 13 with liver cirrhosis (LC) and 11 without LC (non-LC). Portal venous flow could be measured in all patients without any disturbance of intestinal gas or patient fat, or the high degree of technical skill that Doppler US requires. PVFR30 was significantly lower in the LC group than in the non-LC group. In addition, it correlated significantly with other indicators of liver function, including the indocyanine green clearance test, prothrombin time, hepaplastin test, and cholinesterase activity. These results suggest that PVFR30 measured by 2D PS MRI can be used to estimate liver function, and that this MRI method can be performed more easily than pulsed-Doppler US.     

Propeptin,a new inhibitor of prolyl endopeptidase produced by microbispora II. Determination of chemical structure

The structure of propeptin, a new inhibitor of prolyl endopeptidase isolated from Microbispora sp. SNA-115, was determined. FAB/MS, Edman degradation and amino acid analysis revealed propeptin to be a cyclic polypeptide consisting of 19 common L-amino acids. By FAB/MS and protein chemical methods, the primary sequence of propeptin was determined to be Gly1-Tyr-Pro-Trp-Trp-Asp-Tyr-Arg-Asp9-Leu-Phe-Gly-Gly-His-Thr-Phe-Ile-Ser-Pro19, which cyclizes between the beta-carboxyl group of Asp9 and the a-amino group of Gly1.     

Metastasis of breast cancer to intracranial meningioma: case report

Metastasis of systemic cancer to intracranial tumors is a rare event. The authors report a case of 49-year-old woman with such occurrence, whose breast cancer metastasized to a preexisting parasagittal meningioma at a postoperative interval of 1.5 years. She was admitted to our hospital because of progressive right hemiparesis. Magnetic resonance imaging revealed newly emerged perifocal edema and inhomogeneous contrast enhancement of the meningioma. High choline/creatine ratio and lactate/lipid peak on proton magnetic resonance spectroscopy suggested malignancy. She underwent a tumor resection, and pathologic examination revealed intratumoral metastasis of breast cancer in a transitional meningioma. Immunoreactivity of E-cadherin was detected in both meningioma and breast cancer cells. It is suggested that abrupt appearance of symptoms, inhomogeneous enhancement, and perifocal edema of meningioma is a sign of intratumoral metastasis from systemic cancers.     

Frequent mutations of Fas gene in nasal NK/T cell lymphoma

Fas (Apo-1/CD95) is a cell-surface receptor involved in cell death signaling through binding of Fas ligand. Mutation of Fas gene in lymphoid cells results in accumulation of these cells, which might thus contribute to lymphomagenesis. We examined the open reading frame of Fas cDNA in 14 cases of nasal NK/T-cell lymphoma. Mutations of Fas gene were detected in seven (50%) of 14 cases which comprised four frameshift, two missense, and one silent mutations. Frameshift mutations were caused by insertion of 1 bp (A) at nucleotide 1095 in two cases and by deletion of 1 bp at nucleotide 597 and at 704, respectively, in one each. Mouse T-cell lymphoma cells transfected with two missense mutated genes and frameshift mutations caused by insertion of 1 bp (A) at nucleotide 1095 were resistant to apoptosis induced by the anti-Fas antibody. These findings suggested that accumulation of lymphoid cells with Fas mutations provides a basis for the development of nasal NK/T-cell lymphoma.     

Evaluation of preoperative simultaneous radiochemotherapy combined with carboplatin and tegafur.uracil

We performed preoperative radiochemotherapy including local irradiation with total dose of 40 Gy along with concomitant combination chemotherapy with carboplatin and tegafur.uracil for 11 head and neck squamous cell carcinomas and evaluated the clinical and histopathological effects as well as the side effects. Seventy-three percent of patients accomplished significant clinical effects equal to or more than PR and significant histopathological effects in surgically resected tissues. Side effects were seen in only one patient with severe hypoleukocytemia, no patients with renal dysfunction, and 34% of patients with severe oral mucositis. These results suggest that our radiochemotherapy may be useful for preoperative treatment for patients with locally advanced head and neck squamous cell carcinomas.