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J Hilkens

Publications and source records attributed to J Hilkens.

65 records · Page 4Linked to original sources
PubMed1984

The influence of formalin and paraffin embedding on the immunohistochemical reaction of monoclonal antibodies applied to female breast tissue.

Monoclonal antibodies, raised against purified human milk fat globule membranes, were applied to human tissue and the corresponding antigenic determinants detected by an immunoperoxidase method. In human breast tissue, the presence of antigenic determinants was characterized by considerable heterogeneity although it is confined to epithelial cells and cannot be detected in non-epithelial areas. The effect of fixation and paraffin embedding on the reaction pattern was evaluated on tissue from 25 primary breast carcinomas. For each tumor, both frozen, acetone fixed and fixed, paraffin embedded tissue was available. Four of the eight applied antibodies could detect fewer positive cells in formalin-fixed tissue as compared to frozen, acetone-fixed tissue from the same tumor. The positive peroxidase reaction was better preserved after fixation in Lillie's solution. Treatment of formalin-fixed tissue with pronase did not give a better effect. Antibodies with preserved positive reaction in formalin-fixed breast tissue were applied to a range of epithelial and non-epithelial human malignant tumors of varying origin. A heterogeneous positive reaction could be detected in the majority of tumors derived from epithelial cells, but not in non-epithelial tumors.

Antibodies, Monoclonal↗
PubMed1983

Identification of a cellular receptor for mouse mammary tumor virus and mapping of its gene to chromosome 16.

Pseudotypes of vesicular stomatitis virus (VSV) containing envelope glycoproteins provided by C3H mammary tumor virus (MTV) instead of the normal VSV G-proteins were prepared and used to assay the presence of an MTV receptor on cells. The assay was specific as demonstrated by competition studies with excess MTV particles and neutralization of the pseudotypes with anti-MTV serum or monoclonal antibodies directed against MTV gp52. The MTV receptor was abundantly present on mouse cells but hardly detectable on nonmurine cells, including the Chinese hamster cell line E36. Somatic cell hybrids between E36 cells and GRS/A spontaneous leukemia cells (GRSL cells) and between E36 and GRS/A primary mammary tumor cells were made. The hybrids retained all Chinese hamster chromosomes but segregated mouse chromosomes. From the analysis of the isoenzymes and chromosomes of the hybrid cell lines we conclude that the gene for the receptor (MTVR-1) is located on mouse chromosome 16.

Animals↗
PubMed1983

Genetic marker patterns of inbred strains of mice at the Cancer Research Institute, Bombay.

36 genetic markers were examined in 14 inbred strains of mice maintained at the Cancer Research Institute, Bombay. The genetic marker profiles of these strains when compared with the profiles of similar strains maintained elsewhere revealed discrepancies in 4 of them which are reported and discussed. The results emphasize the importance of genetic monitoring of inbred strains.

Alleles↗
PubMed1982

Cross-reactions between tumor cells and allogeneic normal tissues. Inhibition of a syngeneic lymphoma outgrowth in H-2 and non-H-2 alloimmune BALB/c mice.

To test whether alloimmunization with H-2 or/and non-H-2 different normal tissues may increase the immunity to syngeneic tumors, groups of BALB/c (H-2d) mice were immunized with a series of allogeneic lymphoid cells and then challenged i.p. with syngeneic lymphoma cells. The outgrowth of otherwise lethal doses of the Moloney virus-induced lymphoma YC8 and of its clones was inhibited in BALB/c mice immune to DBA/2 (H-2d), C3Hf (H-2k), C3H.SW (H-2b), C3H.OH (H-2o2) and to B10 background tissues but not in mice immunized to A/He, BALB.K (H-2k) or BALB.B (H-2b) normal tissues. Anti-YC8 effect was also induced by immunizing BALB/c recipients with a pool of five different allogeneic cell lines which included C3Hf, C57BL/6J (H-2b), N:NIH (H-2q), B10.M (H-2f), and DBA/2 lymphoid cells. No growth inhibition of other BALB/c lymphomas induced by Moloney virus (LSTRA), X-rays (RL male I) or urethane (UR-1) was evident in alloimmune mice. In vivo transfer of growth inhibition of YC8 was obtained with BALB/c anti-B10.D2 peritoneal exudate cells in a Winn assay. The ability of these alloimmune lymphoid cells to delay significantly the survival time of BALB/c mice injected with the mixture of immune cell and YC8 cells was abrogated by anti-Thy 1.2 plus C' treatment. In addition, nu/nu BALB/c mice were unable to develop resistance to YC8 outgrowth after alloimmunization. The results of this study show that: (1) syngeneic growth of a lymphoma can be prevented by alloimmunization with normal cells; (2) this cross-reaction involved non-H-2 antigens; (3) the phenomenon appeared to be mediated by T cells.

Animals↗
PubMed1982

Acquisition of proviral DNA of mouse mammary tumor virus in thymic leukemia cells from GR mice.

Male mice of strain GR develop T-cell leukemia at a low frequency late in life. These leukemia cells contain large amounts of mouse mammary tumor virus (MMTV) RNA and MMTV proteins in a precursor form (Nusse et al., J. Virol. 32:251-258, 1979). We used restriction enzyme analysis and molecular hybridization to identify MMTV proviruses in the DNA of these leukemia cells. GR leukemia cells contained additional integrated MMTV proviruses at various sites in the genome. This amplification of MMTV proviruses in GR leukemia cells is not restricted to one particular endogenous MMTV provirus of strain GR. The number and location of the extra MMTV proviruses present in transplants of GR leukemia cells did not change upon serial transplantation of the leukemia cells. Acquisition of MMTV proviruses was also found in a similar leukemia, L1210 of the DBA/2 mouse strain, but not in three other leukemias, SL2 of DBA/2, BW5147 of AKR, and a spontaneous thymoma of BALB/c. The two main classes of MMTV RNA, 35S and 24S, were present in the cytoplasmic RNA of GR leukemia cells, indicating that the aberrant processing of MMTV precursor proteins is not due to anomolously sized RNAs. We could not detect extra RNAs in GR leukemia cells which would represent read-through transcripts of cellular genes adjacent to the extra MMTV proviruses, initiated by a promoter signal in the right MMTV long terminal repeat sequence. These data suggest that acquisition of MMTV proviruses may coincide with the onset of leukemogenesis in GR male mice.

Animals↗
PubMed1981

Monoclonal antibodies against human acid alpha-glucosidase.

Acid alpha-glucosidase purified from human placenta was used to immunize a mouse (strain Balb/cHeA) according to a procedure described earlier (Stähli, C., Staehlin, T., Miggiano, V., Schmidt, J. and Häring, P. (1980) J. Immunol. Methods 32, 297-304). After fusion of spleen cells with myeloma cells, about 10% of the hybrid clones obtained produced antibodies against acid alpha-glucosidase. Finally, eight stable clones producing antibodies against the enzyme were obtained. When purified acid alpha-glucosidase is analyzed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate, two major protein bands (mol. wt. 76000 and 70000,) a minor band of mol. wt. 9600 and several minor bands with a mol. wt. of 67000 or lower are seen. Since all these components react with the monoclonal antibodies, they must have at least one antigenic determinant in common.

Animals↗
PubMed1980

Localization of a gene for expression of mouse mammary tumor virus antigens in the GR/Mtv-2- mouse strain.

The GR/Mtv-2- mouse strain is congenic to the GR strain but lacks the Mtv-2 gene for high amounts of mouse mammary tumor virus (MMTV) virion particles in the milk and early mammary tumors. With a sensitive competition radioimmunoassay for individual viral proteins of MMTV, substantial amounts of the gag proteins p27 and p10 could still be detected in extracts of the mammary glands of GR/Mtv-2- mice, but essentially no viral envelope antigens. The genetic transmission of the MMTV gag expression in the GR/Mtv-2- strain was investigated. In a cross with the virus-negative BALB/c strain, the MMTV p27 expression behaved as a dominant feature. Double backcross analysis proved that the p27 expression was governed by a single gene located on chromosome 11, cloe to the Es-3 locus. The gene was thereby not allelic to any of the previously described MMTV induction genes, Mtv-1 and Mtv-2, and is therefore called Mtv-3. It is concluded that the total MMTV expression in the GR strain is under control of two separate loci, Mtv-2 on chromosome 18, inducing high levels of complete virus particles and also early mammary tumors; and Mtv-3 on chromosome 11, coding for partial MMTV expression.

Animals↗
PubMed1979

Identification of a mouse gene required for binding of Rauscher MuLV envelope gp70.

Mouse chromosome segregating somatic cell hybrids were established between a mouse thymic leukemai cell line (GRSL) and Chinese hamster E36 cells. The GRSL cells specifically bound purified Rauscher leukemia virus gp70 while the E36 cells exhibited no binding. The hybrids selectively bound Ruascher gp70 depending on the presence of a mouse cellular gene for the ecotropic murine luekemia gp70 receptor. A syntenic relationship was observed between the DIP-3 chromosome marker (on chromosome 5) and the gp70 receptor in primary clones and subclones of these hybrids; this was confirmed by chromosome analysis. The involvement of H-2 in the binding of Rauscher MuLV gp70 could be ruled out, because discordancies of the receptor presence and H-2 absence as well as of the receptor absence and H-2 presence type could be observed. Our results indicate that the Rec-1 (replication ecotropic MuLV) gene of Gazdar et al. (4) may well be the receptor gene for the ecotropic murine leukemia virus.

Animals↗
PubMedDate not supplied

Depolarized expression of episialin (EMA, MUC1) in lung adenocarcinoma is associated with tumor progression.

Carcinoma cell detachment is an important step in tumor progression and metastasis. Episialin (EMA), if expressed throughout the entire cell surface, may inhibit cell-cell and cell-matrix adhesion. We investigated whether the cellular distribution of episialin in non-small cell lung cancer (NSCLC) is associated with tumor progression. We evaluated the expression of episialin by immunohistochemical staining, in surgical specimens from 122 adenocarcinomas and 99 squamous cell carcinomas. Episialin was present in most NSCLC, with a higher percentage of immunoreactive neoplastic cells in adenocarcinoma than in squamous cell carcinoma (p = 0.0001). In adenocarcinoma the depolarized pattern was significantly associated with nodal metastasis (p = 0.005) and with advanced stage (p = 0.007). In conclusion, nodal metastasis and advanced pathological stage in adenocarcinoma are associated with a depolarized cellular distribution of episialin, suggesting a possible involvement of the molecule in cancer metastasis.

Adenocarcinoma↗