bluuebunny/crossref_metadata_2025 huggingface dataset:
Neoantigens on spontaneous and carcinogen‐induced rat tumours defined by in vitro lymphocytotoxicity assays
Authors: Baldwin R. W. , Embleton M. J.
Published: February 2007

Lymph‐node cells from rats bearing tumours apparently lacking in tumour rejection antigens were cytotoxic in vitro for cultured tumour cells. The specificities of these reactions differed, however, from those demonstrated with immunogenic chemically‐induced rat tumours since cross‐reactivity was observed, especially between tumours of the same histological type. This was most clearly demonstrated in tests with rat mammary carcinomas where tumour‐bearer lymph‐node cells were cytotoxic for a range of mammary carcinomas including spontaneously arising and chemically‐induced tumours. The reactivities of tumour‐bearer lymph‐node cells could be blocked by pre‐treating target cells with serum of tumour‐bearing rats and also by sera of multiparous rats. Conversely, tumour‐bearer sera were highly effective in blocking embryo cells from attack by sensitized LNC from multiparous rats. The results suggest that antigens detected on these tumours by the in vitro assay were embryonic components which were immunogenic in the tumor‐bearing host, although they were not capable of inducing tumour‐rejection reactions in immunized rats.
In vitro inhibition of tumour cell growth and DNA synthesis by peritoneal and lung macrophages from mice injected with corynebacterium parvum
Authors: Olivotto M. , Bomford R.
Published: February 2007

Peritoneal and lung macrophages from CBA mice injected with Corynebacterium parvum were tested for in vitro inhibition of growth and DNA synthesis of syngeneic tumour cells. Peritoneal macrophages inhibited the growth of RI leukaemia cells, and the DNA synthesis of RI leukaemia and T3 fibrosarcoma cells. Maximum inhibition of DNA synthesis was at 5 days after C. parvum injection. Inhibition was most effective when contact between macrophages and target cells was allowed, since medium from macrophage cultures was only slightly inhibitory. Macrophages maintained alone in culture for 48 h lost their ability to inhibit RI cell DNA synthesis. Lung macrophages inhibited the DNA synthesis of RI cells most effectively 14 days after C. parvum injection.
A bank of frozen peripheral blood lymphocytes for In vitro immunological studies on east African cancer patients
Authors: Steel C. M. , Levin A. G. , Tsu T. , Gross R. L.
Published: February 2007

A bank of peripheral blood lymphocytes, frozen in liquid nitrogen, has been established from East African cancer patients and from control donors including healthy individuals and patients with non‐malignant disorders. The techniques of collection, lymphocyte separation and cell freezing are simple enough to have been applied successfully in an isolated mission hospital. In the first year of operation samples have been stored from over 400 individuals. On recovery, the cells have high viability, will respond to PHA in culture, are suitable for determination of HL‐A phenotype and react with sheep red blood cells in the spontaneous rosette test. It is predicted that lymphocyte banks of this type will have a useful place in the study of immunological factors in cancer, particularly in developing countries.
Ethylhydrazine hydrochloride as a tumor inducer in mice
Authors: Shimizu Hidesuke , Nagel Donald , Toth Bela
Published: February 2007

The lifetime administration of 0.0125% ethylhydrazine hydrochloride in drinking water to randomly bred Swiss mice, beginning at 7 weeks of age, induced tumors of the lungs and blood vessels. Eighty‐eight percent of the treated females and 62% of the treated males developed lung tumors, whereas among the controls, the incidence was 21% in the females and 23% in the males. In addition, the incidence of blood‐vessel tumors rose from 5 to 60% in the females and from 6 to 16% in the males, as compared with the controls. The gross and light microscopic investigation of the tumors showed adenomas and adenocarcinomas of the lungs and angiomas and angiosarcomas of the blood vessels of characteristic appearance. This investigation proves for the first time the tumorigenicity of this chemical. The environmental significance of hydrazine derivatives is discussed in the light of the obtained results.
Rat α1F. XI. Immunological control of cell proliferation: Increased growth rate and α1F production by morris hepatoma 5123tc in rats treated with anti‐thymocyte serum
Authors: Bernstein P. , Wepsic H. T. , Sell S.
Published: February 2007

The administration of anti‐thymocyte serum (ATS) to rats bearing transplantable Morris hepatoma 5123tc resulted in an increase in the growth rate of the tumor and in the rate of alpha1fetoprotein (α1F) production by the tumor. ATS‐treated rats not only had faster growing tumors and correspondingly higher serum α1F concentrations than untreated 5123tc tumor‐bearing rats, but also the amount of α1F per gram of tumor tissue was significantly greater. In addition, the mitotic index of tumors in ATS‐treated animals was twice that of the tumors in control animals. The results indicate that the rate of α1Fa production by hepatomas that have the capacity to synthetize α1Fa is directly related to the number of proliferating cells present at any given time. In addition, this report clearly demonstrates that the rate of growth of a tumor is not a fixed property of the tumor but may be accelerated by immunosuppression of the tumor‐bearing animal.
Reduced transplantability of syngeneic tumors in rats immunized with allogeneic tumors
Authors: Kobayashi Hiroshi , Gotohda Eiki , Kuzumaki Noboru , Takeichi Noritoshi , Hosokawa Masuo , Kodama Tadao
Published: February 2007

The growth of transplanted syngeneic tumors in Wistar/KA (WKA) rats was inhibited by three immunizations with tumors from allogeneic Donryu rats which possibly are unrelated antigenically. Inhibition of syngeneic tumor growth was not associated with the source or type of the tumors (carcinoma and sarcoma) used. A slight inhibition was also observed in rats immunized with a large amount of xenogeneic tumor or allogeneic normal spleen, liver and kidney cells. Inhibition was also observed after immunization with syngeneic tumors artificially infected with murine leukemia virus. However, the inhibition was strongest in rats immunized with allogeneic tumors. The mechanism of inhibition may be immunological, and it may be associated with an increase in the non‐specific immunity of the host.
Immunosuppressive and immunostimulatory factors produced by malignant cells In vitro
Authors: Wong Alfred , Mankovitz Ralph , Kennedy James C.
Published: February 2007

The addition of small numbers of irradiated mouse fibrosarcoma cells to cultures containing syngeneic mouse spleen cells and sheep erythrocytes resulted in almost complete inhibition of the expected anti‐sheep hemolytic plaque‐forming cell responses; the addition of even smaller numbers resulted in stimulation rather than inhibition. This same pattern was reproduced when various other types of syngeneic or allogeneic malignant cells were tested under similar conditions; the presence of strong (H‐2) histocompatibility differences had no apparent effect. Metabolically active irradiated malignant cells were required to produce inhibition; dying cells or soluble extracts of cells were ineffective. However, serum‐free supernatants from healthy cultures of non‐irradiated fibrosarcoma cells were found to be inhibitory at high concentrations and stimulatory at low concentrations, in a pattern similar to that found when intact irradiated fibrosarcoma cells were used. High‐speed centrifugation of such supernatants sedimented the stimulatory material but left the inhibitory material in solution. When syngeneic fetal fibroblasts were substituted for the fibrosarcoma cells, it was found that both the intact fibroblasts and their culture supernatants were stimulatory, and that the stimulatory material could be sedimented as before by high‐speed centrifugation. However, very little inhibitory effect was produced by either intact fibroblasts or their culture supernatants, except when unusually high concentrations were used. It is concluded that at least some types of healthy malignant cells release soluble material capable of inhibiting immune responses: their non‐malignant counterparts produce little if any inhibitor.
Virus‐augmented tumor transplantation antigens: Evidence for a helper antigen mechanism
Authors: Boone Charles W. , Paranjpe Meera , Orme Thomas , Gillette Ronald
Published: February 2007

While the homogenate of a transplantable SV40‐transformed fibrosarcoma of BALB/c mice was without tumor transplantation antigen (TTA) activity, a homogenate of the same tumor cells after infection with influenza virus or vesicular stomatitis virus retained TTA activity to a degree approaching that of whole cells. Ultraviolet inactivation of the virus in the homogenate did not affect its TTA activity. Strong evidence for a helper antigen mechanism was provided by two findings: (1) Mice made tolerant to influenza virus could no longer be made tumor‐immune with the virus‐infected tumor homogenate, and (2) priming mice with three weekly injections of egg‐grown influenza virus abrogated the ability of the virus‐infected tumor homogenate to produce tumor immunity when it was given during the fourth week. Although tumor‐cell homogenates would not induce tumor immunity, they would elicit a delayed hypersensitivity reaction in the foot pad. A working hypothesis that correlates all of the findings is proposed.
Occupational lung cancer among copper smelters
Authors: Kuratsune Masanori , Tokudome Shinkan , Shirakusa Takayuki , Yoshida Minoru , Tokumitsu Yukihiro , Hayano Takao , Seita Mieko
Published: February 2007

Because a remarkably high lung cancer mortality rate was noted among males in a certain town, a case control study was carried out on the basis of mortality cards. The case group consisted of 19 males who died from lung cancer and the control group included 19 males who had died from diseases other than cancer of the lung, urinary bladder, and skin. The only significant difference between the groups was that 11 of the 19 who had died from lung cancer had been employed as smelters in a local copper refinery. Prolonged exposure to arsenic, and possibly also other compounds, seemed to be associated with cancer of the lung. The validity of the diagnosis of these lung cancer cases was also checked by blind examination of chest X‐ray films of the patients with occupational cancer, a group of other lung cancer patients, and the controls. The occupational cancer was diagnosed at a higher rate than the tumors of other lung cancer cases. In all the 11 cases, the disease had become manifest after the men had stopped working at the refinery. None of them had been considered as having occupational cancer by the physicians who treated them, their previous employer, the authorities concerned, their family and friends, or indeed themselves, until this study was conducted. The necessity of a lifelong health care system for ex‐smelters from copper refineries was emphasized.
Induction of neurogenic tumors in C3HeB/FeJ mice by nitrosourea derivatives: Observations by light microscopy, tissue culture, and electron microscopy
Authors: Denlinger R. H. , Koestner A. , Wechsler W.
Published: February 2007

Neurogenic tumors were induced in 32.3% of C3HeB/FeJ mice treated transplacentally with ethylnitrosourea (ENU) and in 10.5% of mice treated intravenously (IV) with methylnitrosourea (MNU). Earlier reports on other strains of mice treated with nitrosourea derivatives indicated that non‐neural tumors, particularly lymphomas, were readily induced. However, tumors of the nervous system did not develop or occurred only in a low percentage of treated mice. Genetic strain of mice appears to influence susceptibility of mice to nitrosoureas. Two brain tumors, an oligodendroglioma in the diencephalon and a mixed neuroblastoma‐glioma of the cerebellum, occurred in 19 adult male mice treated IV every 4 weeks with 25 mg/kg MNU to a total of 175 mg/kg. Neurinomas of cranial nerves developed in 9 of 31 offspring of pregnant mice treated with 20 mg/kg ENU IV on the 19th day of gestation. One MNU‐induced oligodendroglioma and 1 ENU‐induced neurinoma were propagated in tissue culture. Cells of both tumors produced intracerebral (IC) and subcutaneous (SC) tumors following injection into syngeneic mice. Tissue samples from both IC transplanted tumors contained abundant clusters of C‐type RNA viruses in interstitial spaces. Budding virus particles were readily demonstrated on the plasma membranes of tumor cells.
Effects of cyclophosphamide on immunity against chemically‐induced syngeneic murine sarcomas
Authors: Steele Glenn , Pierce George E.
Published: February 2007

The effects of cyclophosphamide (CY) on tumor immunity against syngeneic murine fibrosarcomas induced by 3‐MCA (3‐Methylcholanthrene) were studied using transplantation techniques. Five different groups of BALB/c female mice were challenged with viable cells of a 3‐MCA sarcoma (AT‐008). Mice bearing a sensitizing transplant of this tumor at the time of challenge were significantly resistant compared to non‐sensitized, untreated controls and compared to non‐sensitized mice pretreated with CY. Mice which had been sensitized by inoculation and subsequent excision of this tumor were more resistant than the tumor‐bearing mice. The greatest resistance, however, was observed in mice bearing syngeneic transplants of AT‐008 and treated with CY 6 days prior to challenge. These findings suggest that CY not only fails to suppress but may actually intensify established tumor immunity in this animal system. The results support the suggestion that tumor growth inhibition achieved with some chemotherapeutic agents may be accomplished partially through immunologic mechanisms.
Comparative effect of local radiotherapy and surgery on cell‐mediated immunity against a mouse transplantable mammary tumor
Authors: Le François D. , Troise G. Duran , Chavaudra N. , Malaise E. P. , Barski G.
Published: February 2007

The specific anti‐tumor cell‐mediated immunity was investigated in mice bearing syngeneic transplantable tumors and submitted to local X‐irradiation. For this purpose, in vitro tests evaluating the immunologically specific inhibitory effect of lymphoid cells on target tumor cells were performed. The use of lymphoid cells obtained by peritoneal washings permitted us to follow the evolution of the immune status in the same mice during and after the treatment. At the same time when the non‐treated tumor‐bearing controls were immunologically inactive, being in an immunological “eclipse” phase, a significant reactivation of cellular immunity could be detected in a parallel series of mice, submitted to X‐ray treatment, as soon as the tumors began to decrease in size. This activity could still be detected more than 2 months after complete remission of the tumors. If a decrease in this immunity was observed, it was always premonitory of tumor recurrences and the immunological status of the relapsing animals became comparable to that of the tumor‐bearing non‐treated controls. The results obtained were very similar whether the whole population of peritoneal cells or only the “non‐adhering” fraction of it was used for in vitro tests. However, in the latter case, the immunological reactivation following X‐ray treatment appeared to begin earlier and to last longer. When compared with the surgically treated animals, the mice cured by X‐rays showed an earlier immunological reactivation. This reactivation, once it occurred, lasted in both cases for a comparable period after the total elimination of the tumors.
Attempts to detect virus‐specific DNA in human tumors. II. Nucleic acid hybridizations with complementary RNA of human herpes group viruses
Authors: Hausen Harald Zur , Schulte‐Holthausen Heinrich , Wolf Hans , Dörries Kristina , Egger Herwig
Published: February 2007

DNA derived from various human malignant and non‐malignant tissues was hybridized with radioactive complementary RNA (cRNA) synthetized in vitro with the aid of E.coli‐RNA‐polymerase by using DNA of human herpes group viruses as templates. Epstein‐Barr virus (EBV)‐specific cRNA annealed significantly with DNA from nasopharyngeal carcinoma biopsies as well as with DNA preparations from leukocytes, bone marrow, lymph node and spleen of some patients with infectious mononucleosis. No significant hybridization was observed with either herpes simplex type 2 or type 1 cRNA and DNA from ten cervical carcinoma biopsies. cRNA of human cytomegalovirus and varicellazoster virus did not hybridize with DNA from Kaposi's sarcoma or DNA from heavily infiltrated spleens of patients with Hodgkin's disease. These data do not exclude a role of these herpes viruses in the etiology of cervical carcinoma, Kaposi's sarcoma and Hodgkin's disease. They show, however, that such a relationship (if it exists) must differ quantitatively to a considerable extent from the one observed with EBV in EBV‐associated tumors.
Stimulation of tumor growth by the immune response
Authors: Jeejeebhoy H. F.
Published: February 2007

An attempt has been made to test the immunostimulation hypothesis of Prehn which proposes that, in its initial stages, the immune response to tumour‐specific antigens stimulates rather than inhibits tumor growth. Mice have been injected with cells from three different methylcholanthrene‐induced tumors and the cellular and humoral anti‐tumor immune responses of their peripheral blood lymphocytes and sera have been studied by in vitro techniques. The results have been found to be completely compatible with the immunostimulation hypothesis. Five days after the inoculation of tumor cells, at a time when tumors are still not palpable, the cellular anti‐tumor immune responses of the mice were found to be capable of specifically stimulating tumor growth. Palpable tumors normally appeared in these animals 7–10 days after the inoculation of tumor cells and by day 12 it was found that, in most instances, the stimulatory pattern seen on day 5 had changed to an inhibitory one. Other findings reported in this paper relate to the effect of normal and immune serum on tumor cells and on the interaction between tumor cells and normal or immune lymphocytes. Finally, on the basis of all these results, a hypothesis is presented to explain how tumors grow and why they do so in the face of an immune response directed against antigens specific to them.
The effect of year of birth on the breast cancer age‐incidence curve in Iceland
Authors: Bjarnason O. , Day N. , Snaedal G. , Tulinius H.
Published: February 2007

Among different populations, the shape of the age‐incidence curve for breast cancer is strongly related to the overall incidence of breast cancer in the respective population. Data are available from Iceland for the period 1911–1972. These data show that breast cancer has increased very markedly in Iceland during this period, and that as the overall incidence has risen, so the age‐incidence curve has changed in shape, the relation between the shape and the overall incidence being the same as that now observed in other countries. The change in shape is shown to be explicable entirely as a cohort phenomenon, each decade of birth cohort having an age‐incidence curve of similar shape, but with different overall incidence. Data from some other regions of the world indicate that many of the present differences in the shape of the age‐incidence curve may be the reflection of cohort phenomena.
Growth stimulation of human diploid fibro‐blasts by the tumor promoter, 12‐0‐tetradecanoyl‐phorbol‐13‐acetate
Authors: Diamond Leila , O'Brien Susan , Donaldson Catherine , Shimizu Yoshinobu
Published: February 2007

When the tumor promoter, 12‐0‐tetradecanoyl‐phorbol‐13‐acetate (TPA), was added to freshly seeded cultures of human diploid fibroblasts, cell growth was inhibited for 24–48 h and then proceeded at the same rate as in controls. After the control cultures had become confluent, cell division and the incorporation of tritiated thymidine continued in treated cultures, and the cell yield after 9–11 days was increased by as much as 50% compared to untreated cultures. TPA induced striking morphological changes including a decrease in cell size, suggesting that it may enhance cell division by increasing the number of cells per unit area required for cell‐to‐cell contact and confluence to be attained. TPA produced similar effects when added to growing cultures of NIH Swiss 3T3 mouse embryo and chick embryo fibroblasts. Continuous cultivation of human fibroblasts in the presence of TPA increased the cell yield for approximately five successive passages but did not increase the total number of population doublings over the entire life‐span of the cultures.
False negative and prozone reactions in tests for antibodies to Epstein‐Barr virus‐associated nuclear antigen
Authors: Henle Wener , Guerra Angel , Henle Gertrude
Published: February 2007

Titration of anti‐complementary human sera may yield false negative or prozone reactions in anti‐complement immunofluorescence (ACIF) tests for antibodies to Epstein‐Barr virus‐associated nuclear antigen (EBNA) when the human complement (C') is added to the serum dilutions prior to charging of the target cell smears (two‐stage ACIF test). This effect of anti‐complementary sera and with it a source of error is avoided by using a three‐stage ACIF technique; that is, when the target cell smears are successively overlayed with serum dilutions, C' and fluorescein isothiocyanate‐conjugated antibodies to human βC/βA globulins. The two‐ and three‐stage ACIF procedures yield comparable anti‐EBNA titers with non‐anti‐complementary sera.
Epstein‐Barr virus‐associated complement‐fixing and nuclear antigens in Burkitt lymphoma biopsies
Authors: Reedman Beverley M. , Klein G. , Pope J. H. , Walters Marilyn K. , Hilgers J. , Singh S. , Johansson B.
Published: February 2007

Cells from Burkitt lymphoma (BL) biopsies were examined for Epstein‐Barr virus (EBV)‐associated antigens by complement fixation (CF) tests and by the anti‐complement immunofluorescence (ACIF) test. In CF tests, anticomplementary factors made it difficult to test all the biopsies available. However, biopsies from 19 patients were effectively tested and 12 of these (including two from one patient) contained antigen reacting with a battery of human sera with antibody to EBV but not with sera lacking such antibody. Technical difficulties prevented further characterization of the EBV‐related antigens in the biopsies. Application of the ACIF test to BL revealed the presence of EBV‐related nuclear antigen in biopsies from 11 of 13 patients. Absorption studies indicated that the nuclear antigens of the biopsies were closely related antigenically to the EBV‐determined nuclear antigen (EBNA) previously described in lymphoblastoid cell lines. It is concluded that cells of BL biopsies may contain EBNA in addition to the EBV‐related membrane antigen previously described. The results provide further evidence that BL cells from African patients resemble non‐producer lymphoblastoid cell lines in containing EBNA and therefore appear to be transformed by EBV.
Immunosuppression in Burkitt's lymphoma. I. Cutaneous reactivity to recall antigens: Alterations induced by a tumour burden and by BCG administration
Authors: Magrath I. T.
Published: February 2007

Patients with Burkitt's lymphoma have impaired delayed hypersensitivity to recall antigens (mumps, streptokinase‐streptodornase candidin and PPD) in the presence of a tumour load. The degree of impairment at presentation (which may reach total anergia) is dependent upon the clinical stage and correlates significantly with survival rate (p < 0.02), sustained remission rate (p < 0.05) and remission duration (p < 0.01). Cutaneous reactivity 3 months after chemotherapy is significantly improved overall in spite of the potentially immunosuppressant effects of cyclophosphamide but immuno‐suppression recurs in patients who relapse. BCG, applied by dermal scarification resulted, after 4 weeks, in significant improvement of cutaneous reactivity (p < 0.001), but no improvement in prognosis. The most probable explanation of these findings is that the impairment in delayed hypersensitivity correlates with the tumour volume, which in turn governs prognosis. The level of general immunological responsiveness at presentation seems unlikely to be a crucial factor per se in governing the response to chemotherapy.
The influence of host immunity on the arrest of circulating cancer cells, and its modification by neuraminidase
Authors: Weiss L. , Glaves Dorothy , Waite D. A.
Published: February 2007

The patterns of initial tumour cell arrest of a methylcholanthrene‐induced fibrosarcoma and the Gardner lymphosarcoma were determined after injection of 125IudR‐labelled tumour cells into the systemic circulation of mice. Experiments were performed with normal mice, mice sensitized by bearing ascites or subcutaneous variants of these tumours and animals hyperimmunized with X‐irradiated tumour cells. Tumour‐bearing and hyperimmunized mice were shown to produce humoral and cell‐mediated tumour‐immune responses by membrane immunofluorescence tests and migration inhibition assays of peritoneal exudate cells. In normal mice more than 90% of injected fibrosarcoma cells became localized in the lungs whereas the lymphosarcoma cells were localized primarily in both liver and lungs. The fibrosarcoma cells showed a decreased localization in the lungs and a corresponding increase in the livers, lymphoid tissues and kidneys of sensitized mice. However, the lymphosarcoma cells showed greater localization in the lungs of tumour‐bearing and immunized mice compared with that in control animals. Prior treatment of both tumour types with Vibrio cholerae neuraminidase modified the pattern of cell arrest to some extent in both normal and tumour‐sensitized mice. The relevance of these expriements as a model of the haematogenous metastasis of cancer cells is discussed.
An animal model for meningeal leukemia
Authors: Perk K. , Pearson J. W. , Torgersen J. A. , Chirigos M. A.
Published: February 2007

An experimental model of arachnoid leukemia has been developed from a transplantable guinea‐pig leukemia. The meningeal leukemia develops after chemothera‐peutically induced primary remission. The histopathological pattern observed was similar to that seen in central nervous system involvement in childhood leukemia.
Alteration of in vitro anti‐tumor activity of tumor‐bearer sera by absorption with Staphylococcus aureus, cowan I
Authors: Steele G. , Ankerst J. , Sjögren H. O.
Published: February 2007

Staphylococcus aureus, strain Cowan I, has been shown to contain a cell‐wall substance, protein A, which combines with the Fc part of IgG in most mammalian species. Since the blocking activity of sera from tumor‐bearing individuals has previously been found to be associated with 7S immunoglobulins, it was investigated whether Cowan I could absorb out the blocking activity of sera from rats carrying either isografted polyoma virus induced sarcomas or chemically induced colon carcinomas. In all sera tested, treatment with protein A abrogated the sera's ability to inhibit lymphocyte‐mediated cytotoxicity in vitro. Absorption of sera with Staphylococcus aureus, strain Wood 46, not containing protein A, had no effect on the blocking activity. Admixtures of protein‐A‐treated blocking sera to untreated blocking sera from animals bearing the same tumor type, specifically abrogated the blocking activity, while admixture of Wood 46 absorbed sera, protein‐A‐treated normal sera, or protein‐A‐treated sera from animals bearing a different tumor type did not cause a similar abrogation. The blocking sera from tumor‐bearing rats were not cytotoxic to their specific tumor target cells in the presence of homologous complement. After protein A treatment, serum from rats bearing isografts of sarcomas induced by polyoma virus showed specific complement‐dependent cytotoxicity to polyoma tumor target cells. Serum from primary colon carcinoma bearing rats also had complement‐dependent cytotoxic effect on colon tumor target cells after protein A treatment. Sera used for in vitro tests of blocking activity and complement‐dependent cytotoxicity were analyzed for IgG concentration before and after absorption with S. aureus, Cowan I. A 20‐30% reduction of IgG class immunoglobulins as compared to unabsorbed or control (Wood 46) treated sera was demonstrated.
Lipid analysis of cell nuclei in young and old Ehrlich ascites tumors
Authors: Balint Zsuzsa , Holczinger L.
Published: February 2007

The total lipid content of whole cells and isolated nuclei of Ehrlich ascites tumors was found to increase in parallel with increasing age. Mainly triglycerides were accumulated both in the cells and in the nuclei, but the nuclear fraction showed also an increase in the total cholesterol content. No marked accumulation of lipid droplets could be observed in isolated nuclei, and thus it can be presumed that in the course of aging the increase in neutral lipid content is due to a profound alteration in the lipid composition of lipid‐containing nuclear structures.
Natural expression of feline type‐C virus genomes. Prevalence of detectable FeLV and RD‐114 GS antigen, type‐C particles and infectious virus in postnatal and fetal cats
Authors: Gardner Murray B. , Rasheed Suraiya , Rongey Robert W. , Charman Howard P. , Alena Barbara , Gilden Raymond V. , Huebner Robert J.
Published: February 2007

The group‐specific (gs) antigen of RD‐114, an endogenous type‐C virus of domestic cats, was detected by complement fixation (CF) in two of 100 fetal cats and was not detected in any tumors or spleens of postnatal cats. RD‐114 virus was isolated in vitro in RD human sarcoma cells from two of 31 normal cat fetuses but not from any postnatal cat tumors or spleens, with one exception. Feline leukemia virus (FeLV) gs antigen was detected by CF and type‐C particles were seen by electron microscopy (EM) in high prevalence in young cats with lymphoma (65%), anemia (75%) and infectious peritonitis (25%). FeLV gs antigen, type‐C particles and infectious FeLV were occasionally (10‐20%) found in cat fetuses. The general absence of FeLV gs antigen in the endometrium of pregnant cats and the low prevalence of detectable FeLV gs antigen in cat fetuses suggest that the epigenetic transplacental spread of infectious FeLV is not a common occurrence in domestic cats. However, the isolation of FeLV from two pairs of fetal littermates and from the endometria and spleens of both mother cats indicates that such an epigenetic transmission of FeLV can occasionally occur. There was an excellent correlation between detection of RD‐114 and FeLV gs antigen by CF tests in fetal and postnatal tissues and the subsequent isolation in vitro of the corresponding virus. In lymphoma‐ and carcinoma‐bearing cats over 10 years of age, FeLV gs antigen, type‐C particles and infectious virus were seldom found. RD‐114 and FeLV gs antigens or infectious virus were never detected in the same tissues, the same cat or the same litter. These findings are discussed in relation to the natural history of these two different feline type‐C virus genomes.
Cell relationships in transformation of human leukocytes by epstein‐barr virus
Authors: Pope J. H. , Scott W. , Moss D. J.
Published: February 2007

Transformation of human leukocytes by the QIMR‐ WIL strain of EB virus in vitro involves co‐operation between adherent cells (probably macrophages) and non‐adherent cells (predominantly lymphocytes). It was shown that the proliferating cells were derived from the non‐adherent population. Unlike macrophages, autochthonous fibroblasts did not enhance proliferation when cultured with non‐adherent cells, but apparently were inhibitory. A strain of allogeneic fibroblasts was not inhibitory. Inoculation of nonadherent cells with EB virus was essential for transformation, while inoculation of macrophages only was insufficient. It appears from these results that infection of non‐adherent cells with QIMR‐ WIL EB virus induces some cells to proliferate, and that the enhancing role of the macrophage does not involve infection with virus.
The incidence of lung tumours in C57BL mice exposed to cigarette smoke:Air mixtures for prolonged periods
Authors: Harris R. J. C. , Negroni G. , Ludgate Susan , Pick C. R. , Chesterman F. C. , Maidment B. J.
Published: February 2007

C57BI mice, allowed to breathe a cigarette smoke:air mixture for short periods and at frequent intervals throughout their lives, develop a higher incidence of lung cancers, adenomas and carcinomas, than untreated control animals. Smoke from cigarettes made from a flue‐cured tobacco (T2) was more toxic and elicited cancers more quickly than that from cigarettes made from air‐dried tobacco (T3) from the same crop. Filtered smoke :air from T2 and unfiltered smoke gave similar yields of lung tumours.
Facilitation and inhibition of B16 melanoma by BCG in vivo and by lymphoid cells from BCG‐treated mice in vitro
Authors: Chee D. O. , Bodurtha A. J.
Published: February 2007

Groups of mice were pretreated with varying dosages of BCG, then injected with B16 melanoma cells. In mice pretreated with high‐dose (0.5 mg) BCG, the tumor grew at an accelerated rate, whereas with low‐dose (0.005 mg) BCG, the tumor grew at a reduced rate when compared to growth in control mice. These data show that BCG could, depending upon dosage, either facilitate or inhibit tumor growth in vivo. Furthermore, lymphoid cells from high‐dose BCG‐treated tumor‐bearing mice were stimulatory to target B16 melanoma cells in vitro if the ratio of lymphoid cells to target tumor cells was sufficiently low (25:1‐200:1), but were inhibitory when the ratio was high (400:1‐1,000:1).
A prospective study in general practice on breast‐cancer risk in postmenopausal women
Authors: de Waard F. , Baanders‐Van Halewijn E. A.
Published: February 2007

A prospective study of breast‐cancer risk in postmenopausal women has been carried out with the cooperation of 50 general practitioners. A total of 7,259 women have been followed up for an average period of 5.4 years (maximum 8.1 years); 70 cases of breast cancer occurred. The main finding was a pronounced effect of body weight and height on breast cancer risk; the significance of this in explaining international differences in incidence is stressed. High parity counteracted the risk of high weight regarding breastcancer. Single women did not show a high risk because of their relatively low body weight. The relative risk in women with a previous mastectomy was five‐fold.
Cytotoxicity of lymphocytes from patients with cancer of the urinary bladder: Detection by A 3H‐proline microcytotoxicity test
Authors: Bean Michael A. , Pees Hans , Fogh Jørgen E. , Grabstald Harry , Oettgen Herbert F.
Published: February 2007

Human lymphocytes (purified from defibrinated venous blood using gelatin sedimentation, nylon column incubation, and Tris NH4Cl lysis of contaminating erythrocytes) were tested for cytotoxicity (CTX) against T24 cells derived from a carcinoma of the bladder and against cell cultures derived from other tissues. The CTX was assessed in a modified microcytotoxicity test (MCT) where loss of 3H‐proline prelabelled monolayer target cells from the surface of micro‐wells indicates destruction of these cells. The number of target cells that remained attached after incubation with lymphocytes (measured as residual 3H‐counts) was compared to the number that remained attached after incubation with control lymphocytes. The results were classified into three categories: (1) specific CTX (destruction only of T24 cells); (2) non‐specific CTX (destruction ofT24 cells as well as other target cells); and (3) negative (no destruction of any type of target cell). Specific CTX for T24 cells was seen more often with lymphocytes from bladder cancer patients (10/27) than from other patients and normal individuals (2/49) (p <0.001) which suggests that this is a disease‐related phenomenon. By contrast, non‐specific CTX occurred with equal frequency amopg bladder patients (6/27) and other patients (9/36), although less frequently among normal individuals (0/13). In addition, lymphocytes that showed specific CTX for T24 cells were found more often in patients with early or superficial bladder cancer (8/15) and less often in patients with advanced bladder cancer (2/12). These results are in agreement with those obtained by others who used the standard MCT that measures target‐cell destruction and influences on target‐cell proliferation.
Fetal proteins occurring in testicular teratomas
Authors: Wahren Britta , Edsmyr Folke
Published: February 2007

Alpha‐fetoprotein (AFP) and carcinoembryonic antigen (CEA) were determined simultaneously in serial samples from patients with teratocarcinomas, testicular tumors of so‐called embryonic origin. These tumor‐associated fetal substances were seen together in four cases, AFP alone was seen in five, CEA in three and neither antigen in two. The embryonic cancer component was present in all primary tumors in which either fetal antigen was detected. AFP was clearly related to progression or regression of tumor while CEA occurred transiently. Four primary teratocarcinomas and four seminomas were established in short‐term tissue culture. Only one of these particular patients had raised serum AFP levels. When, however, the original tumor‐cell suspensions were assayed by radioimmunoassay or indirect immunofluorescence, AFP was detected in three out of the four teratocarcinomas. CEA was seen in a low percentage of cells from two primary teratocarcinomas. No seminoma cells contained either of the antigens. This means that perhaps most teratocarcinomas do indeed produce AFP and/or CEA, although serum assays may be negative. No relationship was found between the occurrence of the two fetal substances.
Malignant transformation of hamster embryo cells in tissue culture by 7,10‐dimethyl benzo(c)acridine
Authors: Markovits P. , Coppey J. , Papadopoulo D. , Mazabraud A. , Hubert‐Habart M.
Published: February 2007

During the 4th passage of hamster embryo cells originally treated with 7,10‐dimethyl benzo (c)acridine, characteristic colonies with transformed cells appeared. This compound is carcinogenic in mice, but its effects on cells in culture have not yet been studied. Each cell line derived from this subculture produces sarcomas in new‐born hamsters. An inoculum of 10,000 cells per animal produced visible tumors in an average time of 67 days. If the number of transplanted cells was increased, the tumors appeared sooner. These experiments, as well as others carried out in our laboratory using other carcinogens, demonstrate that hamster embryo cells cultivated in vitro can be successfully used for transformation studies.
Inheritance of susceptibility to friend mouse leukemia virus. XII. Effects of the Fv‐1 locus
Authors: Odaka Takeshi
Published: February 2007

The genetic control of susceptibility to the Friend leukemia virus (FLV) complex was studied under conditions which excluded the effect of the Fv locus. From hybrids between two mouse lines which have the same Fv genotype, but differ from each other in response to FLV infection, partially inbred lines were established by selecting for high or low ability to support multiplication of the N‐tropic FLV complex. The results indicated that the Fv‐1 locus controls multiplication of the FLV complex and of the lymphatic leukemia virus (a viral component of FLV complex) and also the development of late splenomegaly. Gene interaction between Fv and Fv‐1 in determining the susceptibility to FLV complex was discussed.
Influence of 5‐bromodeoxyuridine on the expression of avian GS antigen in mammalian rous sarcoma virus‐transformed cells
Authors: Sovová V. , Sainerová H. , Urbánková M. , Hloěánek I.
Published: February 2007

The avian group‐specific (gs) antigen in the virogenic RSV‐transfarmed LW13‐RsKl and LW13‐RsK4 cells is detectable in the perinuclear zone of the cells only by immunofluorescence tests. After treatment of cells with 5‐bromodeoxyuridine (BUdR) it is detectable even by complement‐fixation tests and the immunofluorescence tests reveal its presence in the whole cytoplasm of tumour cells. The increased expression of gs antigen is, however, transient. Attempts to induce gs antigen in the non‐virogenic RSV‐transformed cells after BUdR treatement failed.
Immunogenicity, antigenicity and mechanisms of tumor rejection of mineral‐oil‐induced plasmacytomas in syngeneic BALB/c mice
Authors: McCoy J. L. , Dean J. H. , Law L. W. , Williams J. , McCoy N. T. , Holiman B. J.
Published: February 2007

Transplantation immunity studies were conducted to determine whether mineral‐oil‐induced plasmacytomas of syngeneic BALB/c mice possess tumor‐associated transplantation antigens (TATAs). In a series of experiments to determine whether TATA could be detected, it was established that the optimum immunization regimen against TATA was obtained by immunizing syngeneic hosts with an intradermal inoculation of viable plasmacytoma cells, followed by therapeutic drug‐induced tumor regression with aniline mustard. This immunization regimen induced transplantation immunity not only to the homologous tumor employed for immunization, but was effective in demonstrating some cross‐protection when mice were rechallenged with other plasmacytomas. Thus, definite cross‐reactivity of antigens was observed between some plasmacytomas, but others shown to possess TATA did not share antigens. These, therefore, may possess distinct TATA (s). Further, studies with Winn assays employing cells from BALB/c mice immune to plasmacytoma cells support the idea that cell‐mediated immune functions are responsible for syngeneic plasmacytoma rejection. Specificity studies in subsequent Winn assays demonstrated that the kill was directed against plasmacytoma cells and not against TATA (s) of an MLV‐induced Moloney leukemia and SV40 virus‐induced tumor cells. The nature of the TATA (s) detected is not known, but they probably represent new “cell‐associated” antigens acquired during malignant transformation. Finally, the selective removal of the thymus‐dependent cell component of the immune lymphocyte population with anti‐theta serum and complement eliminated the tumor‐neutralizing properties of the immune cells in the Winn assay.
Cellular immunity against tumor‐associated antigens in humans: Lymphocyte stimulation and skin reaction
Authors: Vànky Farkas , Klein Eva , Stjernswärd Jan , Nilsonne Ulf
Published: February 2007

3 M KCl‐extracts prepared from human tumors (14 sarcoma, 2 astrocytoma, 3 Wilm's nephroblastoma and 1 melanoma) and from non‐malignant tissues (8 muscle, 4 skin, 2 cartilage, 1 kidney, 2 brain and 1 bone marrow) have been used to stimulate autohgous and allogeneic lymphocytes and as antigen in autologous skin tests. The results of the lymphocyte stimulation by autologous tumor‐biopsy cells and their KCl‐extracts were concordant. Moreover, these in vitro results correlated well with the in vivo immune reactivity indicated by skin tests. Tumor‐cell suspensions were weak allogeneic stimulators, and KCl‐extracts were stimulatory only after presensitization. When a tumor‐cell sample and its KCl‐preparation were used in autologous and 11 allogeneic tests the degree of autologous stimulation with tumor cells was as high as the highest allogeneic one and the KCl‐extract stimulated the autologous lymphocytes to the same degree. The results strengthen the validity of the lymphocyte stimulation test as an assay for tumor‐specific reaction.
Cell‐mediated cytotoxicity against human bladder cancer
Authors: Bloom Eda T. , Ossorio R. Clifford , Brosman Stanley A.
Published: February 2007

Lymphocytes from patients with bladder, renal or prostate carcinomas, or with non‐malignant genito‐urinary disorders, and from normal individuals, were tested in a microcytotoxicity test against cultured bladder cancer cells (T24) and other target cell types. Effector cells were titrated over a range of concentrations against target cells to achieve a quantitative measure of toxicity. Tests were shown to be reproducible by repeat tests of normal donors. Lymphocytes from patients with bladder cancer were more strongly cytotoxic to T24 than lymphocytes from normal healthy donors or from patients with renal or prostatic carcinomas. Cell‐mediated cytotoxicity (CMC) by lymphocytes from bladder‐cancer patients, however, was not significantly stronger than CMC by lymphocytes from patients with non‐malignant GU disorders. Strength of CMC against T24 by lymphocytes from patients with bladder cancer correlated inversely with the extent of disease. Patients with superficial and locally invasive lesions showed strongest anti‐T24 reactivity while patients with disseminated disease had CMC equivalent to normals. In tests against target cells derived from amnion of carcinomas of the breast, cervix and/or colon, CMC by lymphocytes from bladder‐cancer patients was not significantly different from that of any other group. Lymphocytes from all donor groups were cytotoxic at some level to cells from cultures derived from bladder cancer and other tissues, although cell lines differed in apparent vulnerability in CMC tests.
Synthesis of A DNA binding protein in normal and transformed cells
Authors: Rubio Victor , Long Cedric
Published: February 2007

The synthesis of a single‐stranded DNA binding protein (P8) by normal and Kirsten sarcoma‐virus‐transformed mouse cells was measured in serum depleted of growth factors by 3T3/B cells. P8 protein was made by the transformed but not the normal cells and was present during the time of peak DNA synthesis. Normal 3T3/B cells were partially synchronized by growth in depleted serum and a change to regular medium. Following the medium change the rate of DNA synthesis increased to a peak between 15 and 20 h and then fell. P8 protein synthesis coincided with the initiation of DNA synthesis and peaked during the same time period. When aminopterin was added to block DNA synthesis, P8 protein was still made during the period of normal DNA synthesis.
Mobility of concanavalina receptors on the surface membrane of lymphocytes from normal persons and patients with chronic lymphocytic leukemia
Authors: Ben‐Bassat Hannah , Goldblum Natan , Manny Noga , Sachs Leo
Published: February 2007

Lymphocytes, isolated from the peripheral blood of normal persons and patients with chronic lymphocytic leukemia, have been studied for cap formation and agglutinability by Concanavalin A (Con A). Twenty‐eight to 32% of the lymphocytes from 12 normal persons formed a cap and there was a similar frequency in separated B cells. The lymphocytes from 12 patients with chronic lymphocytic leukemia showed 6‐10% cells with a cap. Lymphocytes from the leukemic patients had a higher degree of Con‐A‐induced agglutinability than the lymphocytes from normal persons, and both types of cell bound a similar number of Con A molecules. The results indicate that there are differences in the mobility of Con A receptors on the surface membrane of lymphocytes from normal persons and patients with chronic lymphocytic leukemia.
Inhibition of murine RNA tumor virus replication and oncogenesis by chloroquine
Authors: Pazmiño Nelson H. , Yuhas John M. , Tennant Raymond W.
Published: February 2007

The effects of 7‐chloro‐4‐(4‐diethylamino‐l‐methylbutylamino) quinoline diphos‐phate (chloroquine) on marine RNA oncogenic virus infection and replication were studied in cell culture and in vivo. Replication ofMoloney leukemia virus in cell culture was inhibited by approximately 75% at a drug concentration of 1 s̈/ml. This concentration had no effect on cellular DNA or RNA synthesis or on cell division. Chloroquine at a dose of 50 mg/kg body weight given 15 min after injection of Moloney murine sarcoma virus prevented tumor development in newborn mice; similar treatment inhibited the induction of splenomegaly by Rauscher leukemia virus in adult mice. The effect of the drug is not exerted on the virus particle itself, since incubation of the virus with chloroquine for 30 min prior to infection did not decrease its oncogenicity. Presumably, the drug affects one or more events in virus replication.