bluuebunny/crossref_metadata_2025 huggingface dataset:
Cytolytic activity of interferon‐gamma and its synergism with 5‐fluorouracil
Authors: Le Junming , Yip Yum K. , Vilček Jan
Published: February 2007

Highly purified natural or recombinant human immune interferon (IFN‐gamma) was found to be directly cytolytic to certain tumor cell lines in vitro. Out of 5 human tumor cell lines and one normal fibroblast line tested, the colon adenocarcinoma line HT‐29 and the rhabdomyosarcoma line A673 were highly sensitive to cytolysis by interferon, as determined by 125I‐iododeoxyuridine release in a 72 h microcytotoxicity assay. Cytolysis was marked at IFN‐gamma concentrations of less than I U/ml, and it reached a near‐maximal level at 6.4 U/ml. A synergistic cytolysis on HT‐29 cells of IFN‐gamma and 5‐fluorouracil (5‐FU) was observed at 5‐FU concentrations ranging from 64 to 640 μgl ml. In contrast, no synergism was observed between IFN‐gamma and mitomycin C. The direct cytolytic activity and synergistic cytolysis with 5‐FU of the IFN‐gamma preparations used in the present study were abolished completely by treatment with a neutralizing monoclonal antibody specific for human IFN‐gamma.
Natural antibodies to human T‐cell leukemia/lymphoma virus in healthy venezuelan populations
Authors: Merino Fernando , Robert‐Guroff Marjorie , Clark Jeffrey , Biondo‐Bracho Marilena , Blattner William A. , Gallo Robert C.
Published: February 2007

Serum samples of 769 healthy Venezuelan donors were assayed for natural antibodies to HTLV‐I by the ELISA technique. Specific HTLV‐I antibody prevalence was 6.8% but varied from 1% in Caracas to 13.7% in the Amazonas region and the State of Zulia. Adults infected with Trypanosoma cruzi had the highest HTLV‐I antibody prevalence of 15%. Areas of high antibody prevalence were correlated most strongly with the presence of arthropodborne diseases and to a lesser extent with socio‐economic factors. Genetic factors were not correlated with antibody prevalence. Antibodies were seen in children as young as 3 years of age in the most endemic areas. Antibody titers increased with age, suggesting continuous exposure to the virus. The data provide clues for elucidation of the geographic variation in HTLV‐I antibody prevalence seen Venezuela and other HTLV‐I endemic areas. In addition, they further confirm the Caribbean region as being endemic for HTLV‐I and extend this region to inland areas of South America.
Stable quantitative differences of antigen expression in human melanoma cells isolated by flow cytometric cell sorting
Authors: Lindmo T. , Davies C. , Fodstad Ø. , Morgan A. C.
Published: February 2007

The stability of expression of a membrane antigen on human FME melanoma cells was investigated by means of flow cytometric cell sorting and analysis. The melanomaassociated 250 kd antigen was strongly expressed on all cells, as recognized by binding of the monoclonal antibody 9.2.27. By flow cytometric cell sorting, cells of high and low antigen expression were isolated, and the difference in antigen expression between the two populations was examined as a function of time in culture. Immediately after sorting, the median fluorescence intensities of the two populations differed by a factor of 2.7. After the first few days in culture, much of the range in antigen expression of the parent population was regenerated. However, a lasting difference in antigen expression was established, corresponding to 50% higher density of antigen on the cells sorted for high fluorescence intensity, compared to those sorted for low intensity. After trypsin treatment, which removed the antigen from the cell surface, normal antigen expression was regained after 2‐3 days in culture, with the same difference between the two populations as before the trypsin treatment. The stability of the established difference in antigen expression between the two sorted subpopulations indicates that expression of this antigen is a precisely controlled, heritable characteristic of the FME melanoma cells.
Immortalization of peripheral blood lymphocytes of cats by human T‐cell leukemia virus
Authors: Hoshino H. , Tanaka H. , Shimotohno K. , Miwa M. , Nagai M. , Shimoyama M. , Sugimura T.
Published: February 2007

Peripheral blood lymphocytes of domestic cats were co‐cultivated with lethally irradiated MT‐2 cells, which produced human T‐cell leukemia virus type I (HTLV‐I). Two cat lymphoid cell lines, CaL‐l and CaL‐2, established and maintained without exogenously added T‐cell growth factor, were characterized after more than 6 months of cultivation. These cells grew in suspension, had a chromosome number of 38 and lacked cytoplasmic and surface immunoglobulins. CaL‐2 cells formed E‐rosettes. Both cell lines harbored HTLV genomes but not human Alu family sequences, which are highly repetitious in the human genome, suggesting that transfer of human DNA fragments was not necessary for their immortalization or transformation. HTLV antigens were detected in CaL‐l and CaL‐2 cells by indirect immunofluorescence assay. CaL‐l and CaL‐2 cells both expressed viral proteins with apparent molecular weights of 53 kd, 24 kd and 19 kd, and CaL‐2 cells also expressed 28 kd and 20 kd proteins. Reverse transcriptase activity was detected in culture fluid of CaL‐2 cells, but not of CaL‐l cells. CaL‐2 cells but not CaL‐l cells had syncytium‐induced activity. These findings indicated that lymphocytes of cats, especially T lymphocytes, were susceptible to infection with HTLV and to immortalization by HTLV.
Biogenic silica fibre promotes carcinogenesis in mouse skin
Authors: Bhatt T. , Coombs M. , O'Neill C.
Published: February 2007

Silica fibres derived from plants are common contaminants of human diet in certain regions of the world where oesophageal cancer reaches extremely high incidences. We show here that one of these types of fibre (derived from Phalaris, canariensis L) promotes the occurrence of tumours in the skin of mice initiated with a polycyclic carcinogen. Three experiments are described. In the first, the grain which bears these fibres was added to the diet. This did not result in any abnormality in any part of the gastrointestinal tract, but there was a significant induction of tumours in the skin around the mouth and nose; these were the areas of the body surface which most frequently came into contact with the grain. In the second experiment, the mice were separated from the grain by an intervening wire gauze barrier; a similar number of tumours appeared on initiated mice treated in this way. In this case, contact now occurred most frequently on the dorsal surface, which was rubbed against the gauze barrier, and it was on this surface that the tumours appeared. No tumours appeared if the grain was removed. In the third experiment, pure fibres were isolated from the surface of the grain and boiled in strong nitric acid so as to remove any organic material. When these acid‐cleaned fibres were applied to the initiated skin with light pressure, they promoted carcinogenesis in the same way as croton oil. In each experiment the majority of tumours produced were benign neoplasms, together with at least one squamous carcinoma. It seems possible that the size and shape of these fibres are the critical properties determining their promoting activity. Their mean diameter is 15 μm, their modal length close to 200 μm, and they are sharply pointed with a tip diameter of 0.5 μm.
Influence of migratory blood cells on the attachment of tumor cells to vascular endothelium
Authors: Starkey J. R. , Liggitt H. D. , Jones W. , Hosick H. L.
Published: February 2007

The purpose of this study was to determine whether the presence of migratory blood cells in association with tumor emboli had the capacity to alter the attachment of tumor cells to vascular endothelium. Highly metastatic RT7‐4bs rat hepatocarcinoma cells were labelled with [125]UdR before being allowed to form mixed cellular spheroids incorporating 1) resident peritoneal macrophages, 2) activated peritoneal macrophages, 3) polymorphonuclear leukocytes, 4) splenic T lymphocytes, or 5) splenic B lymphocytes derived from both normal and tumor‐bearing animals. The presence of polymorphonuclear leukocytes or activated macrophages led to a considerable increase in the number of tumor cells attaching to endothelial cell monolayers in vitro. The presence of T or B lymphocytes from either normal or tumor‐bearing rats was without effect on tumor attachment to endothelium. Increased tumor cell retention in the lungs was evident for mixed spheroids containing tumor cells and polymorphonuclear leukocytes compared to homotypic tumor spheroids composed of tumor cells alone. Furthermore, preinjection of polymorphonuclear leukocytes intravascularly or inoculation of tumor cells as heterotypic spheroids containing polymorphonuclear leukocytes increased lung colony formation over that obtained after inoculation of tumor cells alone. Several simple sugars were tested for their ability to block tumor cell, polymorphonuclear leukocyte or activated macrophage binding to endothelium in vitro. The results indicate that the glycosylated cell surface components mediating tumor cell attachment to endothelium are not identical with those mediating attachment of either polymorphonuclear leukocytes or activated macrophages. Medium conditioned during mixed spheroid formation was without effect on tumor cell attachment to endothelium. We conclude that the presence of some, but not all classes of leukocytes can modulate tumor cell attachment to vascular endothelium, an effect most likely mediated by a mechanism involving direct contact between the leukocytes and the endothelial cell monolayer.
Morphology of peritumoral proteoglycan alterations in the rabbit mesentery invaded by V2 carcinoma cells
Authors: Müller‐Glauser Werner , Haemmerli Gisela , In‐Albon Annemarie , Strauli Peter
Published: February 2007

After intraperitoneal implantation into Swiss Silver rabbits, V2 rabbit carcinoma cells invade the mesentery where they form nodules of different size and texture: compact (less than 120 μm in diameter), loose (120‐250 ũm) and mixed (above 200 ũm). Together with tumor development, certain changes take place in the loose connective tissue of the mesentery. Application of TEM, together with use of safranin O, has shown that, in areas free of tumor growth, collagen bundles become thick and heavy and proteoglycan density is increased. Concurrently, the number of fibrocytes, now transformed to fibroblasts, increases. Small, compact nodules are surrounded by a concentrically arranged extracellular matrix. Its overall density is similar to that of nodule‐free areas. In the immediate vicinity of large, loose nodules, all constituents of the extracellular matrix disappear. Adjacent connective tissue is partly destroyed but still contains collagen fibers and proteoglycans. These findings suggest the following: (1) The presence of V2 carcinoma cells induces marked alterations in the structured and non‐structured components of the extracellular matrix. (2) These changes are, at the same time, progressive and regressive and the occurrence of one or the other depends on local tumor progression. (3) Progressive alterations may result from an increased activity of fibroblasts. Since degradative effects, on the other hand, are only seen in the immediate vicinity of larger tumor aggregates, it is assumed that a minimal number of tumor cells is essential for destruction of extracellular matrix.
In vivo induction of tumor‐specific immunity by glycolipid extracts of SV40‐transformed cells
Authors: Ansel Sandra , Blangy Daniel
Published: February 2007

Glycolipid extracts were prepared from various Syrian golden hamster cell lines, either SV40‐transformed or spontaneously transformed. To detect possible SV40‐TSTA activity of the glycolipid preparations, normal hamsters were inoculated with different glycolipid extracts and were subsequently challenged with an SV40 tumor‐cell line. Significant immunoprotection against SV40 tumor challenge was induced with glycolipids obtained from SV40‐transformed cell lines. This was expressed as complete tumor rejection or as a decrease in tumor growth rate, when compared to controls. No protective effects were induced with glycolipid extracts from spontaneously transformed cells. Results suggest that tumor‐specific glycolipids synthesized in cells transformed by SV40 virus could act as tumor transplantation antigens responsible for specific tumor rejection in syngeneic hosts.
Procoagulant activity of macrophages associated with different murine neoplasms
Authors: Guarini Anna , Acero Raffaella , Alessio Grazia , Donati Maria Benedetta , Semeraro Nicola , Mantovani Alberto
Published: February 2007

Mononuclear phagocytes, an integral part of the lymphoreticular infiltrate of human and experimental tumors, might contribute to tumor‐associated fibrin deposition through the development of procoagulant activity (PCA). We have investigated PCA of tumor‐associated macrophages (TAM) in 6 transplanted murine tumors in syngeneic hosts; peritoneal macrophages from tumor‐bearing and control animals were studied also, as reference cell populations. PCA was evaluated by a one‐stage clotting assay immediately after preparation and following incubation in the absence and in the presence of endotoxin. TAM from 5 poorly immunogenic tumors (mFS6, MN/MCA1, R 80/44, M109 and MS2) had basal PCA levels comparable to or somewhat lower than those of peritoneal macrophages from the same animals. Similar PCA was found in peritoneal macrophages from both control and tumor‐bearing animals. Unlike peritoneal macrophages, TAM in all instances failed to respond with increased PCA when exposed to endotoxin in vitro. Failure to respond to endotoxin could not be ascribed to contaminating tumor cells or their products, to the presence of suppressive macrophage populations or to the lack of lymphocyte “help”. TAM from a strongly immunogenic, regressing tumor (MSV sarcoma), in contrast to its non‐immunogenic variant, MS2, and to the 4 other tumors mentioned above, expressed high levels of PCA immediately after isolation. The latter did not increase further following in vitro stimulation with endotoxin. When MSV sarcomas were induced in nude mice, TAM showed PCA levels similar to those of the euthymic hosts, suggesting that the procoagulant response was largely independent of T‐cell‐mediated immunity.
Precursor lesions of oesophageal cancer in a low‐risk population in China: Comparison with high‐risk populations
Authors: Crespi M. , Muńoz N. , Grassi A. , Qiong Shen , Jing Wang Kuo , Jien Lin Jing
Published: February 2007

An endoscopic survey was undertaken in Jiaoxian, People's Republic of China, a population at low risk for oesophageal cancer, to determine the prevalence of precancerous lesions of the oesophagus, and this rate was compared with the prevalence observed previously in high‐risk populations in Iran and Linxian, China. The study involved 252 subjects whose exposure to suspected risk factors was determined by a questionnaire and all of whom underwent physical examination and oesophagoscopy, including cytology and biopsy. Chronic oesophagitis, with endoscopic and histologic characteristics similar to those observed in the high‐risk populations of Iran and Linxian, was found in 28% of the study subjects compared to 80% in Iran and 65% in Linxian. Oesophagitis accompanied by atrophy of the epithelium was found in 0.4% compared to 10.5% in Iran and 10.8% in Linxian. No case of dysplasia was diagnosed in Jiaoxian while this condition was diagnosed in 4% of the subjects examined in Iran and in 8% of those in Linxian. The findings suggest that these lesions are in fact precancerous. Vitamin analysis showed that riboflavin deficiency was widespread in Jiaoxian, as in Iran and Linxian, but was more severe in Linxian than in Jiaoxian. No significant difference was found in the mean levels of retinol, beta‐carotene and zinc between the two populations.
Molecular cloning and analysis of a new variant of human T‐cell leukemia virus (HTLV‐Ib) from an African patient with adult T‐cell leukemia‐lymphoma
Authors: Hahn Beatrice H. , Shaw George M. , Popovic Mikulas , Monico Anita Lo , Gallo Robert C. , Wong‐Staal Flossie
Published: February 2007

We report the identification and characterization of a new variant of HTLV‐I in an African patient with adult T‐cell leukemia/lymphoma (ATL). Proviral sequences were detected by Southern blot analysis in three T‐cell lines established from this patient's peripheral blood lymphocytes (PBL) and lymph‐node cells. We molecularly cloned and analyzed proviruses from two of these cell lines, one established by direct culture of PBL and one established by co‐cultivation of PBL with cord‐blood T cells. These two HTLV clones contained full‐length proviruses which were identical to each other in 44 out of 44 restriction enzyme sites. They were closely related to, but distinct from, the prototype HTLV‐I, having divergence in their envelope and 5′ pX regions and therefore represented a new variant of HTLV‐I. We designated it as HTLV‐Ib. Despite the genomic differences, however, HTLV‐Ib retained its tropism for OKT4+ lymphocytes as well as its ability to initiate and maintain transformation of these cells. The finding of a variant of HTLV‐I in this African ATL patient, along with the results of recent seroepidemiological studies, extends to the African continent the prevalence of HTLV‐I associated malignancy previously identified in the Caribbean and Japan.
Detection of an interferon antagonist, sarcolectin, in human sarcomas and muscles
Authors: Jiang Pan Hong , Chany‐Fournier Françoise , Sarragne Madeleine , Grégoire Anne , Chany Charles
Published: February 2007

In a variety of human sarcomas we detected the presence of a sarcolectin which reversed an established antiviral protection induced by interferon (IFN). For the same protein concentration, this biological activity was significantly increased when compared to that of normal muscles. All the biological characteristics were comparable to those of a sarcolectin found in hamster tissues; namely the capacity to agglutinate cells and its inhibition by specific sugars, migration in sodium dodecyl sulfate gel, and pepsin, heat and sodium dodecyl sulfate stability. Except for its anti‐IFN function and cell agglutinating activity, the biological significances of this sarcolectin is presently poorly understood.
Heat‐shock proteins produced by two human melanoma cell lines: Absence of correlation with thermosensitivity
Authors: Ferrini Umberto , Falcioni Rita , Delpino Andrea , Cavaliere Renato , Zupi Gabriella , Natali Pier Giorgio
Published: February 2007

Two human melanoma cell lines, extremely different in their thermal sensitivity, were pulse‐labelled with (35S)‐methionine after 60 min of exposure at 42° C. For both cell lines, fractionation of the intrinsically labelled proteins by polyacrylamide gel electrophoresis (PAGE) showed increased labelling of a polypeptide band of Mr 72,000, along with a slight reduction of overall protein synthesis. By two‐dimensional electrophoresis, the Mr 72,000 band resolved into multiple pattern components of the same size but differing in isoelectric points. The absence of qualitative and quantitative differences between the two melanoma cell lines indicates that the different thermal sensitivities are unrelated to their ability to express the heat‐shock proteins.
A human nucleolar antigen (pp90) associated with cell growth and its induction by epstein‐barr virus and human cytomegalovirus
Authors: Kamata Tohru , Ohtsuka Masahiro , Watanabe Yasushi
Published: February 2007

Immunofluorescent staining of HeLa cells with rabbit antiserum raised against isolated HeLa cell nucleoli showed bright nucleolar fluorescence. Immunoprecipitation of nuclear extracts obtained from HeLa cells labelled with 35S‐methionine or 32P‐orthophosphate followed by gel electrophoresis of the precipitate revealed a major band of 90 kd. This antigen, called pp90, was judged to be responsible for the nucleolar fluorescence. Serine residues were predominantly phosphorylated in pp90. Similar nucleolar fluorescence was observed commonly in human cells derived from malignant tumors including acute lymphatic leukemia, adult T‐cell leukemia, hepatitis B virus‐associated hepatoma, adenocarcinoma, and in 5 lymphoid cells derived from Burkitt lymphoma but not in normal human lymphocytes or liver cells. In immunoprecipitation, 32P‐labelled pp90 was commonly detected as the major component in all of those cells which showed nucleolar fluorescence. Resting human embryo lung (HEL) cells were negative for both nucleolar fluorescence and pp90 in immunoprecipitation, but turned positive when stimulated to grow, suggesting the involvement of pp90 in cell growth. Antigen pp90 was also induced in human lymphocytes and HEL cells by infection with Epstein‐Barr virus in human cytomegalovirus, respectively, which are known to induce cell DNA synthesis in early stages of infection. A crossreacting nucleolar antigen was detected in 2 monkey cells but not in 3 rodent cells tested.
Oral contraceptives containing chlormadinone acetate and cancer incidence at selected sites in the German Democratic Republic ‐ A correlation analysis
Authors: Nischan P. , Ebeling K.
Published: February 2007

The use of oral contraceptives containing chlormadinone acetate in 1972 by women of 13 districts (out of 15) of the GDR has been related to the incidence of cancer of breast, corpus uteri, and ovary during the period 1961 to 1980. Cancer incidence was represented by cohort parameters showing the risk of the cohorts in relation to each other. No statistically significant association between the two events was noted. Although not significant, our data are consistent with an elevated relative risk for breast cancer of 1.3 and a decreased risk for ovarian cancer of 0.5.
Dopamine receptors in a human colonic cancer cell line (HT29). Some receptor‐related biological effects of dopamine
Authors: Scemama J. L. , Ruellan C. , Clerc P. , Clemente F. , Ribet A.
Published: February 2007

The presence of dopamine receptors in normal colonic cells has been postulated from physiological studies. The existence of such receptors in human colonic tumor cells and their role in tumor progression are still unknown. The aim of the present work was to characterize the dopaminergic receptors in a human colonic adenocarcinoma cell line (HT29) and to evaluate the effect of dopamine on cAMP, protein and DNA synthesis. The binding characteristics of 3H‐dopamine on the tumor cells were rapid, reversible, specific, saturable and stereospecific. The first site characterized corresponds to a D3 subtype: KD 3.09 nM, insensitive to sulpiride, unrelated to adenylate cyclase. Competitive inhibitions of 3H‐dopamine binding by different drugs showed the existence of a second binding site, D1, with an apparent affinity for dopamine of 6,700 nM. The rank order of potency of inhibitors of 3H‐dopamine binding was: haloperidol > dopamine > cis flupenthixol > (+) butaclamol > (−) butaclamol > trans flupenthixol > isoproterenol > clonidine > prazosin. D3 binding sites are modulated with age, Bmax was 116 fmol/106 cells on the 5th day and decreased to 8.2 fmol/106 cells on the 15th day of culture. Cell culture in serum‐deprived medium allowed an increase in the number of high‐affinity receptor sites. D1 sites are coupled to adenylate cyclase as shown by a dose‐dependent cAMP accumulation from 10−8 M to 10−5 M dopamine concentrations. Interacting with D1 sites, dopamine evokes an increase in protein synthesis with no modification of 3H thymidine incorporation. The present results indicate that the human colonic cancer cell line HT29 exhibits dopamine receptors and that stimulation may induce metabolic modifications in the tumor cells.
Immune rejection mechanisms in murine leukemia. I. Timing of tumor cell rejection process relative to the development of humoral and cell‐mediated cytotoxic immune responses
Authors: Ciavarra Richard P. , Terres Geronimo
Published: February 2007

Studies were undertaken to investigate the relationship between cell‐mediated and humoral immune responses in the rejection of LI210/MTX‐Rev (LR) leukemia cells in CD2F1 mice. The anti‐LR antibody (humoral) response was defined by both its cytotoxic antibody titer and isotype composition, assessed by a complement‐dependent cytotoxicity assay and radioimmune assay, respectively. The cytotoxic thymus (T)‐derived lymphocyte response in the spleen was quantitated by 125I release by 125I‐IUdR‐labelled target cells. Analysis of the sera of tumor‐bearing mice indicated that the LR leukemia cells elicited a wide spectrum of anti‐tumor antibody isotypes. In mice that mounted a rejection response, the IgM anti‐LR response was transient, while in those that did not, the IgM response persisted. Antibody titers for all isotypes remained low until the onset of LR rejection. At that time, high titers of IgG anti‐LR antibodies, predominantly of the IgG2a subclass, were detected in sera of tumor‐free mice. Thus, the LR rejection response coincided best with the appearance of high titers of IgG2a anti‐LR antibodies. A single i.p. injection of viable LR cells elicited a potent cell‐mediated immune response; neither the appearance nor the magnitude of the cell‐mediated immune response as measured in the spleen correlated well with the onset or the strength of the LR rejection response in the peritoneal cavity. The LR peritoneal cell population grew unabated in the presence of an intense spleen cell‐mediated immune response, and the rejection process began at a time when little cellular immunity could be detected. These results suggest that in the rejection response IgM antibodies contribute little, if any, to the process, and the role of cytotoxic T lymphocytes is questionable (uncertain). The rejection of LR cells appears to be primarily mediated by IgG2a antibodies.
Adoptive immune therapy in mice bearing poorly immunogenic metastases, using T lymphocytes stimulated in vitro against highly immunogenic mutant sublines
Authors: Dennis J. W. , Laferté S. , Man M. S. , Elliott B. E. , Kerbel R. S.
Published: February 2007

MDW3, a highly immunogenic and non‐tumorigenic (tum−) mutant of the poorly immunogenic metastatic murine tumor called MDAY‐D2, has been employed in an immune therapy scheme for the treatment of widespread established visceral MDAY‐D2 metastases in syngeneic mice. MDW3 was selected from a mutagenized population of MDAY‐D2 cells for the ability to grow in the presence of toxic concentrations of wheat‐germ agglutinin (WGA) in vitro. The mutant expresses a common tumor‐associated antigen (TAA) present on MDAY‐D2 as well as a new antigen whose presence enhances the anti‐TAA cell‐mediated immune response in vivo and in mixed lymphocyte tumor cultures (MLTC) in vitro. For immune therapy, spleen cells from DBA/2 mice which had rejected an inoculum of MDW3 cells were restimulated in MLTC and injected i.v. into MDAY‐D2 tumor‐bearing mice. Two protocols were used. In the first, mice were given an i.v. injection of 10 MDAY‐D2 cells (“artificial metastasis”) and subsequently treated with 400 R whole‐body irradiation and MDW3‐stimulated T cells. Such mice had a 75% long‐term survival rate, whereas 400 R alone, or no treatment, resulted in 25% and 0% long‐term survivors, respectively. In the second protocol, treatment of mice bearing a 12‐day‐old subcutaneous MDAY‐D2 tumor by surgical removal of the solid tumor, 400 R whole‐body irradiation, and systemic administration of MDW3‐stimulated spleen cells, resulted in a 75‐100% survival rate, whereas omitting any part of the treatment resulted in 0‐50% survival rates. The treatment increased splenic anti‐TAA CTL activity, and the mice acquired immunity against the new antigen on MDW3, suggesting that the injected lymphocytes were proliferating in the host. The optimal combination of resection, whole‐body irradiation and passive infusion of MDW3‐stimulated spleen cells was ineffective when used on mice bearing a tumor‐antigen‐loss variant of MDAY‐D2, suggesting that success of our immune therapy protocol required specific recognition of the tumor‐associated antigen of MDAY‐D2.
Mouse lewis lung carcinoma and hepatoma ascites treatment by combination of liposome chemotherapy and non‐specific immunotherapy
Authors: Patel Kanaiyalal R. , Baldeschwieler John D.
Published: February 2007

Liposomes have been used as biological carriers of anti‐tumor drugs, and their potential use has been tested in mouse Lewis lung carcinoma and hepatoma ascites tumor models. Ara‐C3 given by the intraperitoneal i.p. route either at 35 mg/kg in a single dose or at 2.5 mg/kg/dose with 5 doses/day for 3 days had no effect on the average survival time of i.v. implanted LLC. However, the same single dose of Ara‐C encapsulated in positively charged MLV significantly improved the average survival time of LLC‐bearing mice. MTX was chosen as a test drug for the treatment of hepatoma ascites. Non‐encapsulated MTX given at either 3 or 30 mg/kg by the i.p. route had little effect on the average survival of i.p.‐implanted hepatoma ascites. However, MTX encapsulated in SUV at a 3 mg/kg dose by the i.p. route significantly improved the average survival time of tumor‐bearing mice. A combination of chemotherapy and non‐specific immunotherapy has also been tested with these 2 tumor models. Two non‐specific microbial immune stimulators, Bacillus Calmette Guérin (BCG) and Corynebacterium parvum (CP) were tested by both the i.v. and i.p. routes. A combination of BCG therapy with non‐encapsulated anti‐tumor drugs was not effective for either of the tumor models. A combination of BCG therapy with liposome therapy appeared to improve the average survival time of LLC‐bearing mice. In particular, BCG treatment by the i.p. route in combination with liposome therapy resulted in a 20% long‐term survival rate among treated mice. However, BCG therapy by either route in combination with SUV encapsulated MTX therapy had no effect on the average survival time of hepatoma ascites‐bearing mice. Immunostimulation with CP at a given dose appears to be superior to BCG therapy for both tumor models. In the treatment of LLC, injection of CP by either the i.v. or i.p. route appears to be equally effective in combination with liposome therapy. However, for the treatment of hepatoma ascites, CP was only effective by the i.p. route, in combination with liposome therapy.
Generation of invasive and metastatic variants of a non‐metastatic T‐cell lymphoma by in vivo fusion with normal host cells
Authors: De Baetselier Patrick , Roos Ed , Brys Lea , Remels Linda , Feldman Michael
Published: February 2007

Intravenous inoculation of the AKR mouse‐strain‐derived BW lymphoma into CBA recipients resulted in a case of liver metastasis; cells derived from this metastatic nodule were termed BW‐Li cells. BW‐Li cells, upon reinoculation, generated metastases in the spleen, liver, kidney and ovaries in 100% of CBA recipients. Furthermore, BW‐Li cells, in contrast to BW cells, were found to infiltrate in vitro monolayers of hepatocytes, thus confirming their inherent invasive potential. Analysis of the alloantigenic phenotype of BW‐Li cells revealed that such cells were Thy 1.1+, Thy 1.2+, Lyt 1.2+, Lyt 1.1−, Lyt 2− and H‐2Dk+, as compared to BW cells which exhibited the membrane phenotype Thy 1.1+, Thy 1.2−, Lyt 1.2−, Lyt 1.1k−, Lyt 2−, H‐2Dk−. BW‐Li cells also differed functionally from BW cells since these cells secreted IL‐2 upon stimulation with Concanavalin A. BW tumor transplantation experiments were repeated in a semi‐allogeneic F1 strain combination, i.e. (AKR × CBA)F1, and again a case of massive liver metastasis was observed. Cells derived from these liver metastases (termed BW‐O‐Li) manifested an invasive and metastatic potential similar to that of BW‐Li cells. Furthermore, BW‐O‐Li cells secreted IL‐2 upon stimulation with Con A and manifested the following alloantigenic phenotype: Thy 1.1+, Thy 1.2+ Lyt 1.2+, Lyt 1.1−, Lyt 2−, H‐2Dk+ and H‐2Kk+. These results indicate that BW‐Li and BW‐O‐Li cells are functional T‐cell hybrids which express T‐cell markers derived from BW cells and Thy 1.2+ CBA host cells. The acquisition of host‐derived T‐cell properties may have led to the expression of metastatic and invasive capabilities. From these results we conclude that the acquisition of metastatic properties following somatic cell fusion with normal lymphoreticular cells may represent a mechanism for tumor progression in vivo.
Possible association between HLA‐DR5 and superficial spreading melanoma (SSM)
Authors: Mueller‐Eckhardt G. , Schendel D. J. , Hundeiker M. , Riedel T. , O'Neill G. J. , Riethmüller G. , Mueller‐Eckhardt C.
Published: February 2007

Previous analyses of possible associations between MHC determinants and cutaneous malignant melanoma (MM) have been inconclusive. We have investigated 98 patients with special emphasis on histologically determined subtypes of MM, and 5 multiple‐case families. In addition to HLA‐ABC and DR typing, complement allotypes of C2, C4A, C4B, BF were determined. Among the unrelated patients HLA‐DR5 and, secondarily, B49 were observed to be associated with superficial spreading (SSM) but not with nodular (NM) or lentigo maligna melanoma (LMM). In families with MM, no definite segregation of the disease according to HLA and complement haplotypes was discernible. Moreover, no coincidence of haplotypes occurred in patients of the different families. HLA region recombinations including B/DR and/or DR/GLO were found in all the families investigated.
Neoplastic x and λ cells in a B‐PLL with chromosome translocations of both light chain gene regions
Authors: Brito‐Babapulle V. , Melo J. V. , Foroni L. , Robinson D. , Parreira L. , Brozovic M. , Catovsky D.
Published: February 2007

We describe a chromosome translocation t(2;13) (p11‐12;p11) involving the kappa (x) light chain gene region (2p11‐12), and a subsequent translocation t(11;22) (q23;11) involving the lambda (λ) light chain gene region (22qll) within the same clone, in a patient with B‐cell prolym‐phocytic leukaemia (B‐PLL), of whose peripheral mono‐nuclear cells 82% expressed (x) chains and 8% expressed (λ) chains. Electron microscope (EM) studies using the immunogold method showed that both x− and λ‐producing cells were prolymphocytes. Immunoglobulin (Ig) gene analysis by Southern blotting demonstrated rearrangement of both Ig heavy (H) chain genes and one x gene. Although a λ gene rearrangement corresponding to the minor λ‐positive population was not detected, a small monoclonal (M) band of IgM‐λ was present in the serum. The chromosome translocations and the pattern of light chain expression, particularly the λ‐producing cells, are discussed in the light of the restricted light chain expression observed in Burkitt's lymphomas with variant translocations involving the light chain genes.
Follow‐up study of hbs ag‐positive blood donors with special reference to effect of drinking and smoking on development of liver cancer
Authors: Oshima Akira , Tsukuma Hideaki , Hiyama Tomohiko , Fujimoto Isaburo , Yamano Hajime , Tanaka Masayoshi
Published: February 2007

In order to confirm the close association between chronic hepatitis B virus (HBV) infection and primary hepatocellular carcinoma (PHC) in Japan, 8,646 male hepatitis B surface antigen (HBs Ag)‐positive blood donors (GPT ± 35 Karmen units) were followed up. Twenty liver cancer cases were observed during the follow‐up period (average 6.2 years), the expected number calculated on the basis of age‐specific incidence rates among the general population being 3.03. Therefore, the observed to expected ratio of liver cancer was 6.60, that is significantly higher than 1.0. During the same follow‐up period, a total of 76 deaths were observed, of which 20 were due to liver cancers and 9 to liver cirrhoses, meaning that nearly 40% of deaths among the study subjects due to chronic liver diseases. Drinking and smoking habits in the liver cancer cases were compared with those observed in healthy male HBV carriers. A strong positive association between drinking habits and liver cancer was observed and there was a significant dose‐response relationship after adjustment for cigarette smoking habits. A high risk of liver cancer was also observed among heavy smokers, but a significant dose‐response relationship could not be found between smoking habits and liver cancer, partly because of the limited number of the study subjects. These findings suggest that HBV is a major etiologic agent of PHC in Japan where the HBs Ag prevalence rate is about 2%, and alcohol drinking and cigarette smoking may promote the process of HB viral hepato‐carcinogenesis.
Epitopes immunologically related to glycophorin a on human malignant and non‐malignant cells in culture
Authors: Barsoum A. L. , Czuczman M. S. , Bhavanandan V. P. , Davidson E. A.
Published: February 2007

Nine monoclonal antibodies specific to different antigenic determinants on the cyanogen bromide fragments CNBr3 (1‐8) and CNBrl (9‐8l) of glycophorin A, the major sialoglycoprotein of human red blood cells, were used for the detection of similar or cross‐reactive epitope(s) on nucleated somatic cells. A panel of human malignant and non‐malignant cells consisting of erythroleukemia, melanoma and carcinomas of breast, cervix, larynx, nasopharynx and colon, as well as human fibroblasts and mammary cells, were tested using a sensitive enzyme‐linked immunoassay. The presence of glycophorin‐like epitopes were demonstrated, in varying concentrations, on all cells tested. These epitropes were found to be localized on the cell membranes by indirect immunofluorescence.
The inhibition of lymphocyte stimulation by autologous human metastatic melanoma cells correlates with the expression of HLA‐DR antigens on the tumor cells
Authors: Taramelli Donatella , Fossati Giuseppe , Balsari Andrea , Marolda Raffaele , Parmiani Giorgio
Published: February 2007

Previous studies indicated that peripheral blood lymphocytes from patients (Pt‐PBL) with lymph node metastatic melanomas proliferated in vitro and developed into tumor‐restricted cytotoxic lymphocytes in response to alloantigens or interleukin 2 (IL‐2). However, Pt‐PBL were not stimulated by irradiated autologous metastatic melanoma (Auto‐Me) cells. In the present study we report that the lack of stimulatory activity of Auto‐Me cells may be due to a suppressive effect exerted by Auto‐Me cells on the responder lymphocytes. In fact, we found that in 62% of cases examined, the addition of 5‐10% Auto‐Me cells to Pt‐PBL cultures strongly inhibited both proliferation and the generation of tumor cytotoxic lymphocytes induced by alloantigens or IL‐2. The inhibition was dose‐dependent and tumor‐restricted, and was not due either to toxicity, medium depletion or IL‐2 absorption by Auto‐Me cells. Normal fibroblasts, K562 cells and autologous E‐ lymphocytes were not suppressive. Auto‐Me cells were able to inhibit Pt‐PBL responses only when added during the first 24 h of culture and not later. Phenotypic analysis of Auto‐Me cells using monoclonal antibodies directed against HLA‐A,B,C, HLA‐DR and melanoma‐associated antigens revealed that the expression of high levels of DR antigens on Auto‐Me cells was associated with an elevated suppressive activity. Conversely, Auto‐Me cells with low or undetectable levels of DR antigens were not inhibitory. Furthermore, the increased expression of DR antigens on Auto‐Me cells obtained by in vitro treatment with human interferon gamma (IFN‐γ) also resulted in an increased suppressive activity. We conclude that HLA‐DR+ metastatic melanoma cells can interfere with the generation of an anti‐tumor immune response, thus potentially favoring the escape of the tumor from the host's control mechanism.
Passive adoptive immunotherapy of low‐immunogenic BALB/C lymphoma by syngeneic alloimmune T lymphocytes
Authors: Colombo Mario P. , Arioli Ivano , Parmiani Giorgio
Published: February 2007

The virus‐induced BALB/c lymphoma YC8 is known to be lysed in vitro by syngeneic lymphoid cells immune to non‐H‐2 antigens of B10.D2 and DBA/2 backgrounds. This tumor is weakly immunogenic in vivo and kills 100% of syngeneic mice with 1 × 103 cells given either intravenously (i.v.) or intraperitoneally (i.p.). We show here that i.v.‐injected YC8 cells grow preferentially in the liver, where colonies become microscopically visible after 7‐10 days, and, less frequently, in the kidneys and spleen but not in the lung. Passive adoptive immunotherapy of this tumor was carried out with alloimmune BALB/c anti‐B10.A, anti‐pool (donors were immunized with lymphocytes from 5 different strains), anti‐A and anti‐DBA/2 splenic and lymph node cells. When administered i.p. 1, 3 or 5 days after tumor cells had been given i.p. and with a schedule of 5 subsequent daily inocula, anti‐DBA/2 lymphocytes cured 100%, 80% and 60% of animals respectively. A weaker effect was obtained with anti‐pool immune cells whereas anti‐B10.A and anti‐A lymphoid cells had not therapeutic effects. When given i.v., the anti‐DBA/2 immune lymphocytes were able to cure both i.v. and i.p. tumor‐injected mice. A significant effect was observed also when the onset of immunotherapy was delayed until 7 or 10 days after tumor injection. By depleting the BALB/c anti‐DBA/2 immune cells with appropriate monoclonal antibodies and complement, it was found that Lyt 1 + 2‐ cells played the major role in eradicating the neoplasm. in vitro phenotypic and functional analysis showed that the immune cell population included 70% of Thy 1 +, 38% of Lyt 1 + and 18‐20% of Lyt 2+ cells. Immune lymphocytes were not cytotoxic in vitro to YC8 or DBA/2 targets whereas they proliferated after restimulation with DBA/2 but only weakly with YC8 cells. This shows that it is possible to cure mice bearing a disseminated lymphoma which expresses non‐immunogenic antigens recognized by BALB/c anti‐DBA/2 immune T lymphocytes. These immune lymphocytes had no cytotoxic activity in vitro and their major effector cell subpopulation displayed the Thy 1+, Lyt 1+ phenotype.
Biochemical characterization of human carcinoma surface antigen associated with protein kinase activity
Authors: Seehafer Jutta , Longenecker B. Michael , Shaw Andrew R. E.
Published: February 2007

MAb 50H.19 immunoprecipitates two proteins from lysates of human carcinoma cell lines, and embryonic fibroblasts intrinsically labelled with 3H‐leucine, 35S‐methionine, or a 3H‐amino acid mixture; a major component of M, = 22,000 (22 kd component) and a minor component of M, = 24,000 (24 kd component). Oligomeric forms of the proteins are not observed under reducing or non‐reducing conditions. Both proteins are expressed on the plasma membrane, and are glycoproteins. We investigated the relationship between the proteins in terms of their glycosylation and derivation from precursors. The 22 kd component is O‐glycosylated as demonstrated by 3H‐galactose incorporation, insensitivity to tunicamycin (TM), and its stepwise generation from a 20.5 kd precursor. The 24 kd protein is N‐glycosylated, as shown by 3H‐mannose incorporation, and by the total inhibition of its synthesis in the presence of TM. Further evidence for its N‐glycosylation is provided by the appearance of a 23 kd precursor in lysates from the osteogenic sarcoma cell line SKOSC pulse‐labelled for 5 min, a time preceding O‐glycosylation of the 20.5 kd protein. Furthermore, mild alkali treatment of the immune complex leads to a loss of approximately 1,000 daltons in each glycoprotein confirming the O‐glycosylated nature of the 22 kd component, and suggesting that the 24 kd component is additionally O‐glycosylated. Both glycoproteins undergo an apparent increase of molecular weight of about 500 daltons when run in the non‐reduced form on SDS polyacrylamide gels under standard electrophoretic conditions, suggesting they contain a similar degree of intra‐chain disulphide bonding. Confirmatory evidence that the two components share a common polypeptide backbone is provided by the appearance of only the 20.5 kd component in lysates from SKOSC cells pulse‐labelled for 5 min in the presence of TM.
Subgroup analysis of BL‐cell lines with polyclonal bl‐specific antibodies
Authors: Gazitt Yair , Ehlin‐Henriksson Barbro , Lerner Ana , Klein George
Published: February 2007

A Burkitt's lymphoma (BL)‐specific antibody (antiGP70), previously described, was used to analyse 22 different BL‐cell lines. The results indicated specificity of antibodies to lines that contain both surface membrane Ig (Smlg) and cytoplasmic Ig (Cylg). BL‐cell lines derived from more immature B cells that do not have Smlg but rather have only Cylg were negative. A comparative study with antibody to common ALL antigen (CALLA) and to another BL‐specific antigen (BLA) revealed coexpression of GP70 with those two antigens, but no identity between them.
Macrophage oxidative burst and related cytotoxicity. I. Differential activation by tumor‐promoting and non‐tumor‐promoting phorbol esters
Authors: Keisari Yona , Flescher Eliezer , Geva Ita
Published: February 2007

Mouse peritoneal macrophages elicit an oxidative burst (OB) response upon stimulation with the tumor promoter 12‐O‐tetradecanoyl‐phorbol 13‐acetate (TPA). In this study we compare the OB‐stimulating capacity of phorbol ester derivatives, structurally related to TPA, which differ in their tumor‐promoting activity. Non‐tumor‐promoting derivatives such as phorbol 13‐acetate, phorbol 12‐myristate, TPA‐2‐O‐aldehyde and 4‐O‐methyl TPA were tested. These reagents stimulate macrophages to generate OB products such as O−2 and H2O2, yet the amounts required for stimulation are 1,000 times higher than the amounts of TPA required to elicit a comparable response. It has also been observed that, in the same order of magnitude, the above‐mentioned derivatives are less efficient than TPA in rendering macrophages cytolytic toward erythrocytes. Another strong tumor promoter tested, teleocidin, has been found to be as potent as TPA in the activation of macrophage OB and in related activities.
Non‐random chromosome changes in a herpes‐virus‐transformed syrian hamster cell line and its metastatic derivatives
Authors: Pratt Norman R. , Lowther Gordon W. , Rees Robert C. , Teale David M. , Potter Christopher W.
Published: February 2007

A primary subcutaneous tumour of low spontaneous metastatic capacity, produced after inoculation of Herpesvirus hominis type‐2‐transformed hamster fibroblasts (parent line) and two in vivo derived highly metastatic lung deposits (Met A and Met B) were karyotyped and compared after trypsin G‐banding. The parent line was cytogenetically heterogeneous with a modal chromosome number of 74. However, a number of cells were of a higher ploidy level. A large variation in both numerical and structural abnormalities was observed, the chromosome rearrangements were often complex and unstable, but all the cells contained a theme of common marker chromosomes. Met A and Met B were near diploid (mean chromosome numbers 42 and 44 respectively) with a low level of tetraploid cells. They shared many chromosome rearrangements but could be readily distinguished by an additional translocation unique to Met A. Cytogenetic homogeneity within and between metastases suggested that they were of monoclonal origin and had been derived from a karyotypically similar subpopulation within the parent tumour. We were unable to detect such cells in the parent line; thus, their numbers within the parent tumour were likely to be low. Metastasis, therefore, has been highly selective, depending on the particular phenotypic properties of Met A and Met B. All cells of the parent and metastatic lines have homogeneously staining regions (HSR) and abnormalities of chromosomes 15 (C15) which may be important in tumorigenesis. In addition, Met A and Met B cells have a number of chromosome rearrangements [translotions, deletions and a double minute chromosome (DM)] not present in the parent cells. They are retained at a high frequency in the cells of Met A and Met B and thus it seems likely that the metastatic phenotype is associated with one or more of these chromosome aberrations.