Use of zinc acetate to treat copper toxicosis in dogs

Zinc acetate was used for the treatment and prophylaxis of hepatic copper toxicosis in 3 Bedlington Terriers and 3 West Highland White Terriers. Two dogs of each breed were treated for 2 years, and 1 of each breed for 1 year. A dosage of 200 mg of elemental zinc per day was required to achieve therapeutic objectives related to copper, which included a doubling of plasma zinc concentration to 200 micrograms/dl and a suppression of oral 64 copper absorption. The dosage was later reduced to 50 to 100 mg/day to avoid an excessive increase in plasma zinc concentration. The preliminary clinical results were good. Three dogs had mild to moderate active liver disease and high liver copper concentrations at the time of initiation of zinc administration. Biopsy of the liver 2 years later revealed a reduction in hepatitis and copper concentrations. One other dog without active hepatitis also had a reduction in hepatic copper concentrations over a 2-year period. All 6 dogs have done well clinically. On the basis of these findings, we believe zinc acetate to be an effective and nontoxic treatment for copper toxicosis in dogs.

Difference in tissue expression of tumour markers CA 19-9 and CA 50 in hepatocellular carcinoma and cholangiocarcinoma

The expression of tumour markers CA 19-9 and CA 50, defined by the monoclonal antibodies 1116 NS 19-9 (19-9 antibody) and C 50, was studied by the immunoperoxidase technique in formalin-fixed, paraffin-embedded tissue sections from 11 hepatocellular carcinomas and 10 cholangiocarcinomas of the liver, and from specimens of normal liver and liver cirrhosis. The 19-9 and C 50 antibodies react with sialosylfucosyllactotetraose, corresponding to sialylated blood group antigen Lewis, and the C 50 antibody also with another sugar moiety, sialosyllactotetraose. Neither marker was cancer specific. The CA 19-9 and CA 50 antigens are normal constituents of bile ducts. Nine out of 10 cholangiocarcinomas stained for CA 50, and eight out of 10 for CA 19-9. There was no apparent difference between the staining pattern of CA 19-9 and CA 50. Hepatocellular carcinomas were consistently negative for both markers. Thus, hepatocellular carcinomas and cholangiocarcinomas showed a clear difference in the reactivity for tumour marker antigens CA 19-9 and CA 50. This difference might be of clinical importance in the differential diagnosis between hepatocellular carcinoma and cholangiocarcinoma.

A comparison of 131I-labeled antibodies, 2-deoxy-2-[18F]fluoro-D-glucose and 68Ga-EDTA in the imaging of human tumor xenografts in nude mice

Three different biological properties--glucose metabolism, gallium imaging and antigen-antibody interaction--have been targeted to image human tumor xenografts implanted in nude mice. Seventy-two experiments were performed in 25 nude mice. Two types of human tumors were used: colorectal carcinoma SW 1116 and melanoma WM 9. Immunoscintigraphic studies produced the highest tumor sampling and confirmed earlier findings that F(ab')2 fragments generate better tumor images than whole antibodies.

Tissue expression of the tumour associated antigen CA242 in benign and malignant pancreatic lesions. A comparison with CA 50 and CA 19-9

The expression of a novel tumour associated antigen CA 242, defined by the monoclonal antibody C 242, was studied by immunoperoxidase staining in formalin-fixed, paraffin-embedded tissue sections from normal pancreata, pancreata with pancreatitis and benign and malignant pancreatic neoplasms. The antigenic determinant of the C 242 antibody is a sialylated carbohydrate structure, related but chemically different from tumour marker antigens CA 19-9 and CA 50. Thirty-eight of 41 (93%) well to moderately differentiated ductal adenocarcinomas of the pancreas and all cystadenocarcinomas were positive for CA 242. The staining was most intense in the apical border of the cells, and in the intraluminal mucus. Only two out of seven poorly differentiated adenocarcinomas stained, and the number of positive cells was smaller than in well differentiated carcinomas. Only occasional cells were stained in one out of five anaplastic carcinomas. Part of large ducts were positive in 91% (21/23) specimens of chronic pancreatitis. In acute pancreatitis small terminal ducts, centro-acinar cells and some large ducts stained for CA 242. In normal pancreas only a few small terminal ducts were CA 242 positive. Carcinomas always stained more strongly for CA 242 than normal pancreatic tissue adjacent to the carcinoma. The results of CA 242 are compared with those of tumour marker antigens CA 50 and CA 19-9. Serum CA 242 levels were determined in 23 of the patients with pancreatic cancer using a fluoroimmunoassay. Fifteen (65%) patients had an elevated value. There was no clear-cut correlation between the serum levels and the immunohistochemical expression of the CA 242 antigen. The expression of CA 242 in pancreatic tissue resembles that of CA 50 and is similar to CA 19-9. The antigen is expressed in serum of many patients with pancreatic cancer and, therefore, is a potential candidate for a serum tumour marker.

Localization of human malignant tumors with radioiodinated recombinant tissue plasminogen activator

Human recombinant tissue plasminogen activator (tPA), labeled with 131I(1.1 to 6.2 mCi) by the iodogen method, was administered intravenously to 15 patients with various soft-tissue malignant tumors after blocking of thyroidal radioiodine uptake. Gamma camera imaging was performed 4 and 24 hr after injection; three patients were also imaged 5 days following injection. We observed accumulation of radioactivity in primary and secondary lesions in 11 patients. In this preliminary study we did not detect any definite association between the magnitude of uptake and type of tumor. Tumors were usually visualized already after 4 hr but the uptake was more intense at 24 hr. The target-to-nontarget ratios at 24 hr, determined by computer analysis of stored images, varied from less than 1.2 to 2.1. This is the first demonstration of accumulation of radiolabeled tPA in malignant tissue. We do not know the mechanism of the uptake but because tPA is known to be avidly bound to fibrin, a component of the stroma of many malignant tumors, it is possible that [131I]tPA is bound to fibrin rather than taken up by the malignant cell; various possible cell uptake mechanisms are discussed. Due to the relatively early maximal uptake of this radiopharmaceutical it will be possible to substitute 123I for 131I, a possibility suggesting a potential clinical use of radioiodinated tPA for the detection of malignant tumors of various origin.

The ovarian cancer associated antigen CA 125 in patients with pleural effusions

The concentration of the ovarian cancer associated antigen CA 125 was determined in the pleural fluid of 25 patients with lung cancer and of 40 patients with benign diseases. Paired serum and pleural fluid samples were measured in 21 tumor patients and 34 patients with nonmalignant diseases. Serum CA 125 was elevated (greater than 35 U/ml) in 16 of 25 (64%) patients with carcinoma and 13 of 34 (38%) patients with benign diseases. The CA 125 level in serum was markedly elevated (greater than 200 U/ml) in five of six adenocarcinomas whereas a slightly elevated level was associated with only one of four mesotheliomas and with one of three secondary carcinomas. The pleural fluid concentration of CA 125 was higher than the serum value in 90% of the patients, showing a median ratio of 4.9, respectively. Pleural fluid values higher than 250 U/ml were seen in 18 of 25 (72%) subjects with pleural effusion due to malignancy and in 10 of 40 (25%) patients in the benign group. There were no apparent differences in the pleural fluid CA 125 levels in patients having different types of cancer and different benign diseases.

Tissue expression of the tumor marker CA 50 in benign and malignant pancreatic lesions. A comparison with CA 19-9

The expression of the tumor marker antigen CA 50, defined by the monoclonal antibody (MAb) C 50, was studied by the immunoperoxidase technique in formalin-fixed, paraffin-embedded tissue sections from normal pancreata, from pancreata with pancreatitis and from benign and malignant pancreatic neoplasms. The results were compared with those obtained with Mab 1116 NS 19-9. The C 50 antibody reacts, like the 1116 NS 19-9 antibody, with sialosylfucosyllactotetraose (corresponding to sialylated blood group antigen Lewisa), but also with another sugar moiety, sialosyllactotetraose. Thirty-two of 37 well- to moderately-differentiated adenocarcinomas and all cystadenocarcinomas were positive for CA 50. The staining was most intense in the apical border of the cells, and in the intraluminal mucus. The number of positive cells was smaller in poorly differentiated adenocarcinomas and only occasional cells were stained in anaplastic carcinomas. In acute and chronic pancreatitis small terminal ducts, centro-acinar cells and some large ducts stained for CA 50. In normal pancreas only a few small terminal ducts were CA-19-9-positive, whereas both ducts and centro-acinar cells were C-50-positive. Normal pancreatic tissue adjacent to carcinoma usually stained more strongly for CA 50 than the carcinoma, whereas the opposite was true for CA 19-9. Eight out of 11 CA-19-9-negative carcinomas were CA-50-positive. Serous cystadenomas and malignant islet-cell tumors were focally positive for CA 50, but negative for CA 19-9. It seems apparent that the C 50 antibody reacts with another determinant than sialylated Lewisa in CA-19-9-negative specimens, serous cystadenomas and malignant islet-cell tumors. Serum CA 50 and CA 19-9 levels were determined in 29 patients with pancreatic cancer. The sensitivity was similar for both markers (76%), and there was a positive correlation between the serum levels. However, there was no correlation between the serum levels and the histological expression of the CA 50 and CA 19-9 antigens.

Sialylated Lewis determinant CA 19-9 in benign and malignant gastric tissue

The expression of the carbohydrate antigen CA 19-9 in human gastric mucosa was studied by using the monoclonal 1116 NS 19-9 antibody, immunohistochemical ABC staining technique and formalin-fixed, paraffin-embedded biopsy specimens. Among 26 gastric carcinoma (GCA) patients CA 19-9 antigen was found in 16 patients (62%). The antigen was also found in 10 (48%) out of 21 non-cancer patients who had benign gastric ulcer and in 9 (12%) out of 74 non-ulcer, non-cancer patients. In non-cancerous mucosa, the CA 19-9 antigen was localized in the surface epithelium (foveolar type of staining) and/or in goblet cells and sometimes in absorptive epithelium of metaplastic intestinal glands (goblet cell type). The foveolar type but not the goblet cell type was related to the nonsecretor status of the subject, to Le positivity and to anti-H negativity of the gastric surface epithelium. It is concluded that, although being commonly present in GCA tissue, the expression of the antigen in benign gastric tissue is too common to advocate the practical value of CA 19-9 in predicting malignant gastric lesions in immunohistochemistry.

Gastrointestinal cancer-associated antigen CA 19-9 in histological specimens of pancreatic tumours and pancreatitis

The expression of the gastrointestinal cancer associated antigen CA 19-9, defined by the monoclonal antibody 1116 NS 19-9, was studied by immunoperoxidase staining in routine formalin-fixed, paraffin-embedded tissue sections from normal pancreata, pancreata with pancreatitis and from benign and malignant pancreatic neoplasms. The formalin-fixed specimens were treated with pepsin, which enhanced the staining intensity. Eighty-five per cent of well to moderately differentiated adenocarcinomas were positive. The staining was most intense in the apical border of cells lining the lumina of malignant glands, and in mucus inside the lumina, but cytoplasmic staining was also seen. In poorly differentiated adenocarcinomas the number of positive cells was smaller and in anaplastic carcinomas only occasional cells were stained. All mucinous cystadenomas and cystadenocarcinomas stained intensely, whereas serous cystadenomas, and all benign and malignant islet cell tumours were negative. Ducts in chronic pancreatitis and in normal pancreata were positive in 96% and 79%, respectively, but the staining was focal and usually weaker than in carcinomas. In acute pancreatitis (92% positive) the staining was more intense, and the CA 19-9 expression was seen predominantly in small terminal ducts and in centroacinar cells. There was an apparent correlation between the degree of differentiation of the ductal adenocarcinomas and the expression of CA 19-9, whereas the correlation between tissue expression and serum levels of CA 19-9 was poor.

Monoclonal antibody-defined antigens of human prostate cancer cell line PC3

Over 600 hybridomas were derived from the immunization of mice with live cells and aqueous extracts of the human prostatic carcinoma cell line PC3. A total of 26 hybridomas with restricted reactivities were selected, subcloned and antibodies tested on a variety of tumor and normal cells. Seven monoclonal antibodies showed reactivity for prostate cancer and other tumor cell lines, including breast carcinomas. Three of the antibodies obtained after immunization with live cells reacted with live cells only and three of the four antibodies obtained after immunization with cell extract reacted with cell extracts and spent culture media. The fourth antibody in the latter group was reactive only in the immunoperoxidase staining assay. Antibody PrS5 recognized a 90,000 molecular weight molecule from 125I-surface-labeled cells in immunoprecipitation analysis. Antibodies PrE3 and PrD8 detected a nonacid glycolipid pentasaccharide from PC3 cells and meconium, and a glycoprotein of 115,000 molecular weight from 125I-surface-labeled red blood cells. The similar patterns of reactivity in RIAs and antigen analysis suggest that antibodies PrE3 and PrD8 recognize the same molecule. The results emphasize the usefulness of immunohistochemistry in the testing of monoclonal antibodies and the impact of the form in which the antigen is presented on the resultant antibody specificity.

Shared antigens of human prostate cancer cell lines as defined by monoclonal antibodies

Eight monoclonal antibodies (MAbs) raised against human prostate cancer cell lines are described. One MAb was derived from the fusion of mouse myeloma P3x63Ag8-653 cells with spleen cells of mice immunized with DU145 prostate cancer cells. The other seven were from the fusion of myeloma lines P3x63Ag8-653 or SP2/0 with spleen cells of mice immunized with PC3, DU145 and 1013L prostate cancer cells. All of the antibodies also reacted with cell lines of other human cancer types, especially carcinomas. Immunoperoxidase staining on fixed tissue revealed strong reactivity only with antibody PrN10. Seven other antibodies seemed to bind to cell surface-associated (glyco)proteins. Antibodies PrL22 and PrO11 showed similar reactivity in radioimmunoassay, and immunoprecipitated a 160 kD molecular weight polypeptide from [125I]lactoperoxidase-labeled cells. Antibodies PrHk an PrQ12 bound to molecules with apparent MW of 115 kD and 100 kD, respectively; antibodies PrM24 and PrP14 revealed a more complex picture in immunoprecipitation of surface-labeled cells.

Characterization of gastrointestinal tumor-associated carcinoembryonic antigen-related antigens defined by monoclonal antibodies

Four major carcinoembryonic antigen-related glycopeptides (Mr 180,000, 160,000, 50,000, and 40,000) were detected in SW948 colon carcinoma cells and in colon adenocarcinoma tissue using a monoclonal antibody (C(4)20-32) generated by immunizing mice with SW1222 human colon carcinoma cells. Only the Mr 50,000 polypeptide was immunoprecipitated from normal colon mucosa by this antibody. Binding studies using other monoclonal antibodies and lectins indicated the different epitopes and carbohydrate attachment sites on each of the four polypeptides. Only monoclonal antibody C(4)20-32 recognized a common determinant on all four polypeptides which was revealed by its reactivity with each affinity-purified component.

Detection of carcinoembryonic antigen and related antigens in sera of patients with gastrointestinal tumors using monoclonal antibodies in double-determinant radioimmunoassays

Of 14 monoclonal antibodies produced in six different laboratories, 13 bound to purified preparations of carcinoembryonic antigen (CEA). All antibodies reacted to spent medium of colorectal carcinoma cell lines. Competitive binding studies indicated that 12 different antigenic determinants representing six different groups were detected on the CEA molecule(s). Six antibodies were used in double determinant radioimmunoassays (RIA) to detect CEA and CEA-related antigens in sera of 311 patients with various gastrointestinal diseases and of normal donors. None of up to 115 sera of healthy donors had elevated antigen levels with four out of the six monoclonal antibodies tested, whereas up to 9% of sera showed elevated antigen levels when tested with two antibodies. Between 1.4% and 4.4% of sera from patients with inflammatory and benign neoplastic diseases of the gastrointestinal tract were positive. Antigen levels were elevated in 56 to 75% (depending on antibody used) of sera from patients with advanced gastrointestinal tumors. These preliminary results indicate that double-determinant immunoassays with a panel of monoclonal antibodies might improve conventional CEA assays by reducing the number of false positive sera detected by polyclonal sera in patients with benign inflammatory bowel diseases.

Monoclonal antibodies to carcinoembryonic antigen (CEA): characterization and use in a radioimmunoassay for CEA

Fusion of immune spleen cells of mice immunized with CEA with a mouse myeloma cell line resulted in several hybrid cell lines secreting antibodies to CEA as tested by radio-immunoassay. Four of these were cloned by limiting dilution and large amounts of anti-CEA antibodies were produced by growing the anti-CEA-producing cell clones intraperitoneally in mice and collecting the ascites fluids formed. Ascites fluids containing antibodies with both high and low affinity were obtained. The antibody having the highest affinity was shown to be specific to CEA, whereas one antibody showed cross-reaction with the normal cross-reacting antigen (NCA). The establishment of a competitive-inhibition doubleantibody radio-immunoassad with high sensitivity and specificity using mouse monoclonal antibodies is described.

Immunoperoxidase staining of carcinoembryonic antigen with monoclonal antibodies in adenocarcinoma of the colon

Mouse monoclonal antibodies to carcinoembryogenic antigen (CEA) obtained by the somatic cell hybridization technique of Köhler and Milstein were used in a modified enzyme bridge immunoperoxidase staining method. Both high and low affinity antibodies were tested and their staining properties compared with those of a commercial polyvalent rabbit antiserum. The staining pattern of neoplastic epithelial cells in all seven antibodies in samples of primary adenocarcinoma of the colon was similar, indicating that no gross differences were found in the exposure of the different antigenic determinants of CEA in formalin fixed tissue. The background staining of the monoclonal antibodies are negligible. It is concluded that monoclonal antibodies are superior to conventional antisera in immunoperoxidase staining of CEA.

Alpha fetoprotein levels in neonatal hyperbilirubinaemia

Serum alpha fetoprotein (AFP) levels were studied in 15 neonatally hyperbilirubinaemic children and 15 controls matched for sex and gestational age. All children were born between 38 and 40 weeks of gestation. During the first seven weeks of postnatal life hyperbilirubinaemic children had serum AFP concentrations over twice as high as controls. At the age of 5-7 days the mean (+/- S.E.M.) serum AFP values were 52.4 +/- 5.8 mg/l for hyperbilirubinaemic children and 24.8 +/- 4.3 mg/l for controls (p less than 0.001). At 20-25 days of age they were 7.28 +/- 1.10 and 2.75 +/- 0.45 mg/l, respectively (p less than 0.001), and at 40-49 days 1.39 +/- 0.21 and 0.46 +/- 0.07 mg/l (p less than 0.001). However, no correlation was found between serum bilirubin and AFP concentrations in hyperbilirubinaemic children.

Carcinoembryonic antigen in fetal tissues and in material serum

The occurrence of CEA was extensively adsorbed to eliminate cross-reactions with CEA-related antigens. After the first trimester of pregnancy CEA was found throughout the gastrointestinal tract by both techniques, whereas the other fetal tissues and fetal serum did not contain detectable amounts of CEA. The CEA-level of all 69 sera of pregnant women was below 2.5 ng/ml. The excretory nature of CEA was suggested by the localization of CEA in the luminal border of the alimentary tract and by the finding that the CEA concentration in the content of fetal gastrointestinal canal was higher than in the surrounding tissue. Gel filtration on Sepharose 4B showed that molecular weight of CEA immunoreactive material of the fetal gut was similar to that of CEA purified from colon cancer, but a minor component with a higher molecular weight was eluted in the void volume. When tested in radioimmunoassay, the CEA immunoreactive material in both peaks gave an inhibition curve parallel to that of purified CEA.

Carcinoembryonic antigen in endoscopic brush specimens from benign and malignant gastric lesions

The measurement of carcinoembryonic antigen (CEA) in serum and endoscopic brush specimens was evaluated for the differential diagnosis of malignant and nonmalignant gastric disease. Brush specimens were studied from 33 patients with gastric cancer and 36 patients with benign gastric lesions or apparently normal gastric mucosa. Demonstrable CEA immunoreactivity was found by radioimmunoassay in brush specimens from 24/33 cancer patients (73%) and from 23/36 patients with benign lesions (64%). Patients with CEA+ tissue in the immunoperoxidase test had somewhat higher CEA concentrations in the brush specimens than cases with CEA- biopsy tissue, although overlap was considerable. Thirty-five per cent of cancer patients had both a positive tissue CEA reaction and a CEA/DNA ratio greater than 10 ng/micrograms, whilst patients with benign lesions had only 15% of positives by these criteria (0.01 greater than P greater than 0.001). The serum CEA concentration was above the upper normal level of 5 ng/ml in 2/39 patients, both of whom had gastric cancer. The CEA immunoreactive material from benign and malignant lesions eluted in gel filtration on Sephadex G-200 in the same volume as CEA purified from liver metastases of cancer of the colon, showing that a glycoprotein sharing immunological and physicochemical properties with CEA is present both in malignant and nonmalignant lesions of the gastric mucosa, and that there is considerable overlapping in the amount of CEA. The estimation of CEA in gastric-brush specimens is therefore of limited value in the differential diagnosis of benign and malignant gastric lesions.