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J Hilkens

Publications and source records attributed to J Hilkens.

At least 55 records · Page 3Linked to original sources
PubMed1987

Immunohistochemical demonstration of MAM-3 and MAM-6 antigens in normal human skin appendages and their tumors.

The expression of MAM-3 and MAM-6 antigens was immunohistochemically investigated on 110 tumors of human skin appendages. Forty-two samples from tumor-adjacent normal skin appendages were also studied. MAM-3 antigens, as detectable by monoclonal antibodies (MoAbs) 67D11, 115G3, and 115H10 were present in the inner layer cells but not in the outer layer cells of normal eccrine excretory ducts. Sporadic positivity was also found in cytoplasm of apocrine acini with 115G3, while 67D11 and 115H10 were negative. MAM-6 antigens, as detectable by the MoAbs 115D8, 115F5, 139H2, 140C1, and 126E7 were found in the secretory canaliculi of normal eccrine acini and within the apical lumina at the terminal portion of ducts. Apocrine acinar cells mainly exhibited an apical staining, but a focal supranuclear dot-like staining could also be observed. A foamy reaction pattern for MAM-6 was noted in mature sebocytes. However, none of the antigenic epitopes was expressed in normal squamous epithelium or hair follicles. In benign tumors, the staining patterns for both antigens, in general, resembled their distribution in the corresponding normal tissues. However, carcinomas originating from sweat glands, sebaceous glands, and the pilar apparatus expressed both antigens in a more irregular and heterogeneous pattern. This might preferably be explained by the loss of those mechanisms controlling the antigen expression in mature, functional tissues. Conclusions from these immunohistochemical studies with regard to the histogenesis mainly of the malignant skin appendage tumors should be drawn with caution.

Antibodies, Monoclonal↗
PubMed1987

Immunohistochemical localization of the epithelial marker MAM-6 in invasive malignancies and highly dysplastic adenomas of the large intestine.

MAM-6 antigen is detectable in a large variety of formalin fixed and paraffin embedded normal and neoplastic tissues throughout the body with some exceptions. One such exception is the large intestine in which normal mucosa has been found negative for MAM-6, while colorectal carcinomas express the antigen in almost all cases. We examined the expression of MAM-6 in 147 benign epithelial tumors (adenomas) of the colorectum and compared this with the detectability of the antigen in 123 colorectal cancers and in 108 non-neoplastic mucosa specimens. The tissue samples were subjected to an indirect immunoperoxidase assay applying the MoAb 115D8 which recognizes the epitope "a" of MAM-6. A majority of the carcinomas (99.2%) and of the adenomas (61.4%) exhibited reactivity for MAM-6 "a", whereas only 8 of the 108 non-neoplastic biopsy specimens (= 7.4%) exhibited faint focal staining. In adenomas, positive reactions were only seen in highly dysplastic tissue areas, in part reflecting carcinomata in situ. The reactivity in four non-neoplastic tissue samples could be explained by shedding of the antigen from carcinomas into glandular structures of the mucosa. Two out of 32 cases exhibiting severe colitis were also focally positive. The detectability of MAM-6 "a" in routinely processed specimens from the large intestine is therefore considered as being closely associated with malignant and premalignant processes. According to a limited study with the antibodies 139H2 and 140C1, this holds true for two additional MAM-6 epitopes. MAM-6 might be considered as a marker of severe (premalignant) dysplasia in adenomas of the large intestine. Further studies are needed to clarify if there is a biological (possibly prognostic) difference between MAM-6 positive and negative high epithelial atypia in these adenomas.

Adenocarcinoma↗
PubMed1986

Detection of surface antigens defined by monoclonal antibodies in primary mucinous breast carcinomas. Relation to prognostic factors and recurrence-free survival.

Three monoclonal antibodies, 67D11, 115H10 and 115C2, raised against human milk fat globule membranes, have been applied to 207 primary mucinous breast carcinomas. The tumours reacted positively in 18% (67D11), 54% (115H10), and 20% (115C2) of the cases. The detected epitopes (MAM-3a (67D11), MAM-3b (115H10), and MAM-3c (115C2)) have formerly been shown to be markers of differentiation in infiltrating ductal carcinomas. In the present group of mucinous breast carcinomas, statistically significant correlation to high risk factors, such as occurrence of primary lymph node metastases, large tumour size, and local invasion of the tumour into overlying skin or deep fascie, were found. Furthermore, the antigen expression was less marked in pure mucinous carcinomas as compared to carcinomas also presenting with non-mucinous tumour areas. Thus, especially the antigen MAM-3b, is more frequently present in mixed tumours, in large tumours, in tumours with local invasion, and in tumours with primary lymph node metastases. However, no association could be demonstrated between expression of MAM-3b and recurrence-free survival. Mucinous carcinomas of the breast apparently differ from other carcinomas not only with respect to morphology, but also in their pattern of antigenic expression in relation to other prognostic factors.

Adenocarcinoma, Mucinous↗
PubMed1986

Genetic mapping of Pim-1 putative oncogene to mouse chromosome 17.

Pim-1 is a putative oncogene activated in T-cell lymphomas induced by Moloney and AKR mink cell focus forming (MCF) viruses. We have determined the chromosomal localization of the Pim-1 gene in mice by Southern blot analysis of DNAs obtained from a panel of mouse-Chinese hamster somatic cell hybrids. The Pim-1 gene was localized on chromosome 17, a chromosome frequently aberrant in T-cell lymphomas. Two chromosomal regions, containing sequences homologous to regions within the Pim-1 locus, were localized on chromosome 6 and 16.

Animals↗
PubMed1986

Development of mouse mammary gland: identification of stages in differentiation of luminal and myoepithelial cells using monoclonal antibodies and polyvalent antiserum against keratin.

The development of the mouse mammary gland was studied immunohistochemically using monoclonal antibodies against cell surface and basement membrane proteins and a polyclonal antibody against keratin. We have identified three basic cell types: basal, myoepithelial, and epithelial cells. The epithelial cells can be subdivided into three immunologically related cell types: luminal type I, luminal type II, and alveolar cells. These five cell types appear at different stages of mammary gland development and have either acquired or lost one of the antibody-defined antigens. The cytoplasmic distribution of several of these antigens varied according to the location of the cells within the mammary gland. Epithelial cells which did not line the lumen expressed antigens throughout the cytoplasm. These antigens were demonstrated on the apical site in situations where the cells lined the lumen. One antigen became increasingly basolateral as the cells became attached to the basement membrane. The basal cells synthesize laminin and deposit it at the cell base. They are present in endbuds and ducts and are probably the stem cells of the mammary gland. Transitional forms have been demonstrated which developmentally link these cells with both myoepithelial and (luminal) epithelial cells.

Animals↗
PubMed1986

MAM-6 antigen, a new serum marker for breast cancer monitoring.

Almost all carcinomas contain a cell surface antigen, MAM-6, which has been defined by several monoclonal antibodies, including 115D8 (Hilkens et al., Int. J. Cancer, 34: 197-206, 1984). A quantitative sandwich radioimmunoassay, using 115D8 as catcher and as tracer antibody, has been developed to detect MAM-6 in serum. To quantitate the MAM-6 level, pooled human milk was used as a standard, and arbitrary units were chosen. Less than 5% of the sera of apparently healthy individuals contained more than 5 units/ml. In sera of patients with benign breast lesions, the same low levels were detected. However, concentrations over 5 units/ml were found in 24, 21, 43, and 79% of the sera of patients with pathological Stages I, II, III, and IV breast cancer, respectively. MAM-6 levels were also increased in almost all sera tested from patients with advanced stages of ovarian carcinoma, but in a low percentage of sera from patients with other advanced cancers. A longitudinal study was carried out to test the MAM-6 assay as clinical marker to monitor the therapeutic response of breast cancer. Increasing or decreasing MAM-6 serum levels correlated in 93% of the cases with breast cancer progression or regression, indicating that the assay can be used to monitor the course of the disease during therapy. In some breast cancer patients, elevated MAM-6 levels were observed prior to any clinical indication of tumor recurrence.

Antibodies, Monoclonal↗
PubMed1985

Novel antigenic specificity involving the blood group antigen, Lea, in combination with onco-developmental antigen, SSEA-1, recognized by two monoclonal antibodies to human milk-fat globule membranes.

Two monoclonal antibodies to human milk-fat globule membranes, which recognize an epithelial antigen designated MAM-3c, were found to bind strongly to epithelial glycoproteins derived from non-secretors. Further investigations, using purified glycoproteins and structurally defined oligosaccharides, established that the optimal antigenic structure for both antibodies involves the Type 1 based blood group antigen, Lea, in combination with the Type 2 based onco-developmental antigen, SSEA-1, (Formula: see text) as in lacto-N-difucohexaose II. The antibodies may also react with the corresponding monofucosyl structures lacking the 3- or 4- linked fucose residues and to a lesser extent with the afucosyl tetrasaccharide sequence as in lacto-N-tetraose. The Lea and SSEA-1 antigens are known to occur on human epithelial glycoproteins. However, this is the first report of an antigenic specificity involving a combination of the Type 1 and Type 2 based fuco-oligosaccharides and occurring on epithelial glycoproteins.

Antibodies, Monoclonal↗
PubMed1985

Localization of the gene for the vitamin B12 binding protein, transcobalamin II, near the centromere on mouse chromosome 11, linked with the hemoglobin alpha-chain locus.

Somatic cell hybrids, recombinant inbred (RI) mouse strains, and backcross breeding experiments were used to locate the gene of transcobalamin II (Tcn-2), the vitamin B12 binding protein in mouse serum. TCN-2 was found to be useful genetic marker in the somatic cell hybrids. Selected hybrid clones were derived from fusions between GR mouse cells and the Chinese hamster cell line E36. Analysis of mouse specific chromosomal enzyme markers in relationship to TCN-2 secretion, in the hybrid clones, provided provisional evidence for assignment of the Tcn-2 locus to chromosome 11. The strain distribution pattern of the TCN-2 variants S and F in the RI series CXS, constructed from the cross of BALB/cHeA (TCN-2S) with STS/A (TCN-2F), implied a close linkage with the hemoglobin alpha-chain locus (Hba) on chromosome 11. Backcross breeding using inbred strains confirmed these findings and located the Tcn-2 gene closest to the centromere, linked with waved 2 (wa-2) and Hba with recombination frequencies of 6.9 and 19.2% each. The linkage group Tcn-2/wa-2/Hba was established.

Animals↗
PubMed1985

Expression of MAM-3 and MAM-6 antigens in endometrial and endocervical adenocarcinomas.

Expression of milkfat globule membrane antigens (MAM-3, MAM-6) was investigated by an indirect immunoperoxidase method on normal and malignant glands of the endocervical and endometrial tissues. MAM-3 antigens, as detectable with monoclonals 67D11 and 115G3, were not detected in normal endometrial glands, but they were found in the majority of endometrial adenocarcinomas. In the endocervix, MAM-3 antigens were present in almost all of the normal glands and in the cancerous glands. MAM-6 antigens, as detectable with monoclonals 115D8 and 115F5, were observed in majority of normal and neoplastic glands within the endometrium and endocervix. The staining appearance of the antigens was generally heterogenous in the neoplastic tissues but more homogenous in normal glandular tissues. These results are discussed and compared with the grade of histological differentiation, mucin production and positivity for CEA.

Adenocarcinoma↗
PubMed1985

Epithelial markers for paraffin-embedded human tissues. Immunohistochemistry with monoclonal antibodies against milk fat globule antigens.

About 200 human tumours and corresponding normal tissue samples were investigated by immunoperoxidase tests for the expression of MAM-3, MAM-5 and MAM-6 antigens, which had previously been defined by monoclonal antibodies to human milk fat globule membranes. All tissue specimens had been treated for routine histopathology, i.e. fixed in formalin and embedded in paraffin. One of the antigens, MAM-6, appeared to be an important epithelial marker, present in all normal and neoplastic breast tissue samples, in about 80% of non-mammary normal tissues and in more than 90% of non-mammary epithelial tumours. It could never be detected in normal and neoplastic mesenchymal and neuroectodermal structures. Direct comparison with the distribution of Carcinoembryonic Antigen (CEA), Tissue Polypeptide Antigen (TPA) and keratin provided clear evidence that MAM-6 is different from these well known epithelial markers. MAM-3 proved to be an additional important marker exhibiting a characteristic distribution pattern in those epithelial tissues investigated. In contrast to MAM-6, it could never be detected in renal cell cancers and carcinomas of the prostate gland, thus allowing differential diagnosis on the basis of immunohistochemistry. MAM-5, known to be associated with lactoferrin, was mainly detectable in secretory organs and their tumours. In the group of breast tumours, its expression was mainly seen in lobular cancers. These findings suggest a use for these new markers for routine histopathology.

Adenocarcinoma↗
PubMed1985

Mouse interferon alpha and beta genes are linked at the centromere proximal region of chromosome 4.

In order to determine the chromosomal localization of the murine interferon-alpha (MuIFN-alpha) and murine interferon-beta (MuIFN-beta) genes the DNAs of a panel of somatic cell hybrids were analysed by Southern blot hybridization. The hybrid cells were derived from E36 Chinese hamster cells and GRSL or GR MaTu mouse cells and retained all hamster chromosomes but segregated mouse chromosomes. The MuIFN-alpha probe used was a 0.7 kb HindIII-EcoRI fragment derived from the MuIFN-alpha 1 gene which hybridized with both mouse and hamster DNA. However, four fragments present in EcoRI digests of mouse DNA were clearly absent from the hybridization profile of EcoRI-digested hamster DNA and could be used for detection of MuIFN-alpha sequences in the hybrid cells. The MuIFN-beta probe, a 0.5 kb BglII-BamHI fragment derived from the MuIFN-beta gene, hybridized with a 2.6 kb EcoRI fragment of mouse DNA and only weakly cross-hybridized with a 4.8 kb EcoRI fragment in hamster DNA. Southern blot analysis of DNA from mouse/hamster hybrids compared with the analysis of chromosome markers showed that both the MuIFN-alpha and the MuIFN-beta genes are located on chromosome 4. Analysis of DNA from hybrids that contained only part of chromosome 4 indicated that the MuIFN-alpha gene family and the MuIFN-beta gene are situated at the centromere-proximal region of the chromosome.

Animals↗
PubMed1985

Prognostic value of surface antigens in primary human breast carcinomas, detected by monoclonal antibodies.

Three monoclonal antibodies, raised against human milk fat globule membranes, have been applied to 194 primary human breast carcinomas. The detected antigenic sites were found to be heterogeneously distributed. A statistical association with estrogen receptor content and grade of anaplasia was found for two of the antigens, Mam 3a and Mam 3b. The presence of all three antigens was independent of menopausal status, age, primary lymph node metastases, and progesterone receptor status. Life table analysis showed a better survival for patients with tumors positive for Mam 3b. The effect of these variables on recurrence-free survival has been analyzed using a Cox regression model. It is found that the most important prognostic factors are the number of positive lymph nodes, the estrogen receptor content, and the menopausal status of the high-risk patients. The ability of a model based on these factors to predict recurrence is not significantly improved by including any of the three surface antigens.

Antibodies, Monoclonal↗
PubMed1984

Monoclonal antibodies against human milk-fat globule membranes detecting differentiation antigens of the mammary gland and its tumors.

Mouse monoclonal antibodies have been raised against human milk-fat globule membranes (HMFGM) to obtain reagents for mammary tumor diagnosis. A panel of 17 anti-HMFGM antibodies was selected for further investigation. Antibody-blocking studies indicated that with these antibodies at least nine different non-overlapping epitopes could be distinguished on six different molecules, MAM-1 to MAM-6. Electron microscopic studies of the cellular localization of the antigens detected by some of these antibodies revealed that they were present on the cell membrane mainly, on the microvilli, lining intercellular and intracytoplasmic lumina. The reactivity of the antibodies was studied on normal and tumor tissues and on in vitro cell lines. All antibodies reacted with the resting mammary gland while eight antibodies also bound to breast tumors. None of the antibodies was specific for the mammary gland or its tumors only, but most antibodies also reacted with other epithelial cells, especially of secretory tissues. When tested on a variety of cell lines a distribution reflecting the tissue distribution could be demonstrated. One of the antibodies reacted with nearly all carcinomas and their metastases and did not react with lymphomas, sarcomas, neuroblastomas, melanomas or nervous system tumors. The specificity of the antibodies, tested individually, was not sufficient for further differential diagnosis of the carcinomas, but when some of these antibodies were used in a panel they contribute to an important improvement of the diagnosis.

Antibodies, Monoclonal↗
PubMed1984

Use of a monoclonal antibody to distinguish between precursor and mature forms of human lysosomal alpha-glucosidase.

The maturation of lysosomal alpha-glucosidase in cultured human skin fibroblasts was studied using a monoclonal antibody that distinguishes between the precursor and mature forms of the enzyme. Monoclonal antibodies against alpha-glucosidase isolated from placenta were produced by the hybridoma technique [Hilkens et al. (1981) Biochim. Biophys. Acta 678, 7-11]. One of these monoclonal antibodies, that synthesized by clone 43G8, reacts with the mature forms, but not with the precursor form of alpha-glucosidase isolated from urine. By means of pulse-labelling studies, it could be shown that monoclonal antibody 43G8 does not react with either the intracellular or the secreted precursor of alpha-glucosidase from cultured human skin fibroblasts. However, the antibody does react with the intermediate and mature forms of alpha-glucosidase. Endocytosis of the precurosor of alpha-glucosidase from urine by fibroblasts is followed by its conversion to a form with lower molecular mass. After endocytosis urinary precursor alpha-glucosidase is converted to a form that binds to monoclonal antibody 43G8. The t 1/2 for this conversion is 2 h. The conversion is inhibited by addition of leupeptin to the culture medium. It is concluded that a thiol proteinase is involved in the maturation of alpha-glucosidase in fibroblasts and the appearance of the antigenic determinant for 43G8.

Antibodies, Monoclonal↗
PubMed1984

Specific localization of In-111-labeled monoclonal antibody versus 67-Ga-labeled immunoglobulin in mice bearing human breast carcinoma xenografts.

A murine monoclonal antibody reacting with more than 95% of all breast cancers was radiolabeled with In-111 and injected IP into nude mice bearing human breast carcinoma xenografts, together with Ga-67-labeled normal mouse immunoglobulin. Images were produced with a gamma camera in dual isotope mode. Tumors could be localized clearly with In-111-labeled specific monoclonal antibody, but improved visualization was obtained after computer-assisted subtraction of the image with Ga-67-labeled nonspecific immunoglobulin. The tumor-to-tissue contrast was improved from 2.3 to 5.9 after subtraction. Imaging with In-111-radiolabeled monoclonal antibody was superior to imaging with iodinated antibody. For the first time it was shown that images of two chemically related isotopes, Ga-67 and In-111, coupled to nonspecific and specific antibody, respectively, and simultaneously injected, can be subtracted to show the preferential uptake of the specific antibody in the tumor. As these isotopes are routinely used in clinical practice this technique may prove to be more practical for immunodetection of tumors in patients than existing imaging techniques.

Animals↗