Miki Aizawa

An AFP-producing gastric carcinoma with features of hepatic differentiation: a case report

A patient with primary gastric adenocarcinoma with extremely high serum alpha‐fetoprotein (AFP) levels (12,000 ng/ml) is described. Histologically, foci strongly resembling hepatocellular carcinoma with hyaline globules were noted. Within tumor cells, AFP was identified with both light and electron microscopy, showing the production of AFP by tumor cells themselves. Furthermore, 88% of serum AFP combined with Concanavalin A (ConA), revealing that it was hepatic‐type AFP and not germcell‐type. Localization of alpha‐I‐antitrypsin within tumor cells was also noted. Ultrastructural study showed that there were two types of structures corresponding to periodic acid‐Schiff (PAS)‐positive globules, one of which, the proteinaceous material in intracytoplasmic lumina, was found to contain AFP. Among gastric adenocarcinomas with a high serum AFP level (several thousand or more ng/ml of AFP), foci resembling hepatocellular carcinomas have been reported by several investigators. Those gastric carcinomas, together with the current case, may constitute a clinicopathologic entity, hepatoid adenocarcinoma of the stomach.

Hepatoid adenocarcinomas of the stomach: an analysis of seven cases

Hepatoid adenocarcinomas of the stomach are gastric carcinomas with both adenocarcinomatous and hepatocellular differentiations. They usually produce large amounts of alpha‐fetoprotein (AFP) with a Concanavalin A‐binding property of hepatic type. In this study, these carcinomas occurred in older persons, with the antrum being a common site. Observed grossly, growth of the tumors was nodular and massive. Prognosis was poor because of frequent liver metastases. In the cytoplasms of tumor cells, various serum proteins were identified, including AFP, alpha‐1 antitrypsin (AAT), alpha‐1 antichymotrypsin (ACT), albumin, and prealbumin. Localizations of ferritin, prothrombin, and transferrin were demonstrated with less frequency. Adenocarcinomatous foci were composed of well‐differentiated, intestinal‐type epithelial cells and often contained carcinoembryonic antigen. These adenocarcinomatous and hepatoid areas were often intermingled with each other. There were extensive venous involvements by tumor cells. The poor prognosis of the tumors may be attributed to these involvements as well as to production of AFP and presence of AAT/ACT, which have immunosuppressive and protease‐inhibitory properties, respectively. Cancer 58:119–126, 1986.

HLA-DQ system and insulin-dependent diabetes mellitus in japanese: does it contribute to the development of IDDM as it does in caucasians?

Fifty-six unrelated Japanese patients with insulin-dependent diabetes mellitus (IDDM) were HLA-typed, and restriction fragment length polymorphism (RFLP) analysis was performed after enzyme digestion with Bam HI and Taq I by using both DR and DQ probes. As previously reported, increased frequencies of Bw54, Cw1, DR4, and DRw53, which are in strong linkage disequilibrium in the Japanese population and make the characteristic Japanese haplotype, were confirmed. DQw4, a new allele of the DQ system recognized by the monoclonal antibody HU-46 and in linkage disequilibrium with this haplotype, presented the highest IDDM association. The RFLP analysis also showed the strongest correlation to IDDM when the DQ probe was applied. These results indicate that HLA-DQ might play the most important role in the development of IDDM in Japanese as well as in Caucasians. The correlation of DQβ amino acid sequences strongly associated with IDDM in Japanese are discussed in this study, and contrasting results were found when such sequences were compared with those of Caucasians.

Evidence for two B-cell alloantigen loci in theHLA-D Region

Antigenic determinants recognizable by human antisera (Hon 7 and 2075abs sera) were found in a partially purified antigen preparation obtained from an HLA-D and -DR homozygous cell line (EBV-Wa). Sequential coprecipition tests showed that two determinants detectable with Hon 7 and 2075abs sera (Hon 7 and 2075abs determinants) were present on different molecules. These two antigenic determinants were shown to be allotypic and were expressed predominantly in the B-cell-rich fraction. Family studies showed that both antigenic determinants segregated concordantly with respectiveHLA haplotypes. In the population study, the 2075abs and Hon 7 determinants were shown to be in strong linkage disequilibrium and the 2075abs determinant perfectly correlated with the HLA-DRw4 specificity. The results indicate that the Hon 7 determinant is coded for by a gene distinct from alleles at theHLA-DR locus. Furthermore, the locus (Hon 7) coding for the Hon 7 determinant is suggested to be very closely linked with theHLA-DR locus.

Serologic dissection of HLA-D specificities by the use of monoclonal antibodies

To study the gene products of theHLA complex, we produced two monoclonal antibodies, termed HU-18 and HU-23. They were active in complement-dependent cytotoxicity and detected B-cell alloantigens encoded by a locus (or loci) linked toHLA. When three types of HLA-DR4 homozygous B-cell lines with different HLA-D specificities were tested for reactivity with HU-18 and HU-23, they displayed distinct reaction patterns depending on the HLA-D specificities they possessed: EBV-Wa (HLA-DYT homozygous), negative for both HU-18 and HU-23; KT2 and KOB (HLA-DKT2 homozygous), positive only for HU-18; and ER (HLA-Dw4 homozygous), positive for both. These differential reaction patterns were further confirmed by testing against a panel of 17 HLA-DR4-positive peripheral blood lymphocytes with known HLA-D specificities. Thus, these monoclonal antibodies allow us to identify HLA-DYT, HLA-DKT2, and HLA-Dw4 solely by serologic methods. This is the first clearcut serologic identification of these three HLA-DR4-associated HLA-D specificities, which have been indistinguishable by conventional serology and identified only by cellular techniques. It is hoped that immunochemical investigations using HU-18 and HU-23 will advance our understanding of theHLA-D region on a molecular level.

Specific Histocompatibility Antigens Associated with BehçEt's Disease

We studied the distribution of HL-A antigens in 44 patients with Behcets disease and in 78 normal control subjects. The antigen frequencies of HL-A5 and 4c were significantly increased in the patients (HL-A5: chi2=22.1, P less than 0001; and 4c: chi2=26.9, P less than .0001).

HLA-linked susceptibility gene of Takayasu disease

The HLA-A, B, DR and MB antigens were investigated in patients suffering from Takayasu disease (Aortitis syndrome). Out of twenty-one HLA-A and B antigens tested, only HLA-Bw52 was significantly deviated (30147, PF = 63.8%, RR = 7.8) from the controls (14/76, PF = 18.4%). Since in the Japanese, HLA-Bw52 is in positive linkage disequilibria with HLA-DR2 and MB1, the association of the DR2 and MB1 antigens with Takayasu disease was studied. The HLA-DR2 antigen was significantly increased (23/30, PF = 76.7%,, RR = 6.0) in patients compared with the control (18/51, PF = 35.3%). Moreover, an almost perfect association of MBI (29/30, PF = 96.7%, RR = 12.6) with Takayasu disease was demonstrated. This finding supports the hypothesis that the genes in the HLA-D region play a major role in determining the susceptibility to Takayasu disease.

Detection of a novel HLA-DQ specificity: serological and immunochemical analyses by a monoclonal antibody

A monoclonal antibody (mAb) with a novel human B-cell allospecificity was produced by immunizing a C3H/He mouse with the human B lymphoblastoid cell line EBV-Wa (HLA-DR4/Dw15/DQblank homozygous). The mAb, termed HU-46, reacted with B cells from not only DR4/Dw15-positive individuals but also certain DRw8/Dw8-positive ones whose DQ phenotypes had not yet been defined. Two-dimensional gel analyses indicated that the mAb recognized class II antigens which were encoded by the HLA-DQ locus. Furthermore, in genetic analysis, the gene encoding the class II antigen detected by HU-46 met the Hardy-Weinberg condition as a fourth allele of the DQ locus. We provisionally labeled this novel DQ specificity DQWa.

PRIMARY YOLK SAC TUMOR OF THE LIVER

An autopsy case of yolk sac tumor of the liver in a 29‐year‐old female was reported. The tumor was found originally in the right anterior segment of the liver on the first operation. The autopsy disclosed that the liver was almost entirely replaced by multiple, round tumor nodules. The tumor masses continuously extended to the peritoneum and to the subcutaneous tissue. There were no tumors in other organs including the ovaries, gut, stomach, lung, uterus, and kidneys, indicating that the tumor originated in the liver. Microscopically, the tumor showed typical characteristics of the yolk sac tumor. An immunohistochemical study showed that AFP was distributed fine granularly in the cytoplasm of tumor cells. Electron microscopic observation disclosed large amounts of electron‐dense material being closely related to basement membrane.

Evidence for polymorphism of MB3 antigens among three HLA-D clusters associated with HLA-DR4

In a previous study, we showed that the three hitherto serologically indistinguishable HLA-D specificities associated with HLA-DR4, HLA-DYT, HLA-DKT2, and HLA-Dw4 can be distinguished on the basis of their reactivity with two distinct la-like-specific monoclonal antibodies, HU-18 and HU-23. In this study, we attempted to identify and characterize Ia-like molecules recognized by HU-18 and HU-23 on a molecular level because la subsets (HLA-DR, MB, MT, or SB) identified by them remained unknown. The results of sequential coprecipitation assays and two-dimensional gel analyses showed that both HU-18 and HU-23 recognize antigenic determinants borne on M133 but not on HLA-DRw6.2 molecules. Because the two monoclonal antibodies, specific for determinants carried on MB3 molecules, show distinct reactivity against homozygous typing cells defining HLA-DYT, HLA-DKT2, and HLA-Dw4, all of which share DR4-MB3, the data indicate that these three HLA-D clusters associated with HLA-DR4 possess distinct MB3 molecules, suggesting the existence of polymorphism in MB3 antigens.