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M J Jager

Publications and source records attributed to M J Jager.

83 records · Page 5Linked to original sources
PubMed1987

Heterogeneous expression of melanoma-associated antigens in uveal melanomas.

Twenty-five uveal melanomas were stained with seven monoclonal antibodies (MoAbs) recognizing different antigens on cutaneous melanomas. A two step immuno-peroxidase procedure was used. Phenotypic heterogeneity was observed for four MoAbs (M.2.2.4, AMF-7, 225.28S, PAL-M1) while two MoAbs (NKI-beteb, CL203.4) reacted strongly with most (85%) uveal melanomas, and one MoAb (R-24) showed very low reactivity. Despite heterogeneity, co-expression of some antigens was observed. Expression of the antigen recognized by MoAb M.2.2.4. was significantly lowered by pre-enucleation irradiation while the other antigens remained unchanged. Expression of antigens on uveal melanomas differed markedly from primary cutaneous melanomas. The clinical relevance of these findings awaits further study.

Antibodies, Monoclonal↗
PubMed1986

Expression of HLA antigens in paraffin sections of uveal melanomas.

Expression of histocompatibility (HLA) antigens on tumor cells may influence the recognition of these tumor cells by the immune system. Immunological recognition may influence tumor growth and patient survival. Although HLA class I and II antigens are known to be present on several tissues in the eye, their presence on ocular tumors had not yet been demonstrated. We studied the expression of these antigens on paraffin preparations of uveal melanomas. Most tumors carried class I and beta 2m antigens on most of their cells while class II antigens were less often expressed. No association with tumor cell type or tumor size was observed. Further studies will be necessary to determine the relevance of different levels of antigen expression with regard to patient survival.

HLA Antigens↗
PubMed1986

Correspondence of the monocyte antigen HMA-1 to the non-HLA antigen 9a.

Monocyte-specific antibodies are detrimental to bone marrow and renal transplantation. By using human antimonocyte sera we were able to identify two monocyte-specific antigens, human monocyte antigen 1 and 2 (HMA-1 and HMA-2). The presence of HMA-1 and HMA-2 was compared with the presence of several non-HLA antigens. In panel and inhibition studies, HMA-1 corresponded to the previously described non-HLA granulocyte antigen 9a. Absorption studies showed that HMA-1 and 9a were both present on granulocytes and monocytes. The clinical relevance of these antigens is discussed.

Antigens, Surface↗
PubMed1986

Recognition of polymorphic monocyte antigens.

Sera from multiparous women and renal transplant recipients were screened for the presence of anti-monocyte antibodies. Reactions caused by anti-HLA antibodies were excluded by using panel cells that were HLA-compatible with the antibody producers. Six sera with monocyte-specific antibodies were identified, and at least two monocyte-specific (probably allelic) antigens could be recognized. The perspective of the clinical significance of typing for monocyte-specific antigens is discussed.

Antigen-Antibody Complex↗
PubMed1985

Comparison of techniques for the detection of monocyte specific antigens.

Monocyte specific antigens are relevant in renal and bone marrow transplantation, but a reproducible monocyte-antigen system has not yet been recognized. In order to establish a sensitive test system with reproducible results in monocyte serology, 3 different monocyte cytotoxicity techniques were compared. In our hands the two-colour fluorescence test on post-Ficoll total leukocyte suspensions fulfilled the criteria. This technique was used to screen sera from multiparous women and renal transplant recipients for the presence of monocyte specific antibodies. By testing sera on cells from individuals who were HLA compatible with the serum donors, anti-HLA reactions were excluded. Several promising sera containing monocyte specific antibodies were identified, thus indicating the success of our approach.

Antigens↗
PubMed1982

In vitro effect of (3-amino-1-hydroxypropylidene)-1,1-bisphosphonic acid (APD) on the function of mononuclear phagocytes in lymphocyte proliferation.

The effect of (3-amino-1-hydroxypropylidene)-1,1-bisphosphonic acid (APD) on pokeweed mitogen-stimulated and non-stimulated cultures of peripheral blood mononuclear cells was studied in vitro. It is shown that APD can inhibit partially lymphocyte proliferation when added to a suspension of mononuclear cells before stimulation, but that lymphocyte proliferation can continue when the drug is withdrawn. In contrast; when APD is added to the cell suspension together with the mitogen, lymphocyte proliferation remains low even when the drug is withdrawn. Addition of different concentration of mononuclear phagocytes (MNP) to non-adherent cells, followed by stimulation in the presence of APD, indicates that APD acts on MNP function preferentially and does not affect lymphocyte proliferation.

Cell Division↗
PubMed1980

A case of pure red cell aplasia with a high incidence of spontaneous chromosome breakage: a possible X-ray sensitive syndrome.

A patient with a pure red cell aplasia (Blackfan-Diamond Anemia), and with many congenital abnormalities and growth retardation, has been found to have a chromosome breakage syndrome. In this patient, the frequencies of spontaneous chromosome aberrations and micronuclei in PHA stimulated peripheral blood lymphocytes are elevated when compared to those in normal individuals. The frequency of sister chromatid exchanges is within normal range. The response to mitomycin C (MMC) in the micronucleus test, using lymphocytes, shows a similar increase in the patient's lymphocytes to that in normal individuals, indicating no increased sensitivity to MMC. The frequencies of X-ray induced dicentric chromosomes and micronuclei in the peripheral blood lymphocytes are elevated in the patient. But as the patient clinically does not have any signs of ataxia telangiectasia, this combination of clinical and laboratory findings of this case does not correspond with any of the other known 'chromosome breakage' syndromes.

Abnormalities, Multiple↗
PubMedDate not supplied

Follow-up of corneal transplantations at the Academic Medical Center of Amsterdam.

In order to determine risk factors in corneal transplantations, corneal transplants performed at the Amsterdam Academic Medical Centre (AMC) were registered and the results evaluated by descriptive statistics and actuarial survival curves. The results showed that the diagnosis prior to transplantation, the number of previous transplants, and the vascularization were important prognostic factors for graft survival. The best results were obtained in the absence of vascularization, in primary transplants and in keratoconus, while vascularization in one or more quadrants and a diagnosis such as herpes resulted in poor graft survival. When, for instance, the negative influences of vascularization can be overcome, better results will be obtained.

Age Factors↗
PubMedDate not supplied

Effect of interferon-alpha on MHC expression and influx of inflammatory cells on the rat eye.

Interferon-alpha can be used as additional treatment of herpes keratitis. However, several studies have demonstrated that interferon-alpha can induce immunological changes in several tissues, and if used in a patient with a corneal transplantation, those changes might induce rejection of the corneal transplant. In order to determine the immunological changes in corneal tissue, we examined the effect of local treatment with interferon-alpha on MHC Class I and II expression, and inflammatory cell influx in the rat eye, and compared this with the changes induced by intrastromal sutures. These changes were evaluated by immunohistology for MHC Class I and II and several immunologically active cells. Intrastromal sutures induced an influx of lymphocytes and macrophages and induction and/or upregulation of MHC Class I and II. Local treatment with interferon-alpha did not have any of these effects. We conclude that topical use of interferon-alpha is not likely to induce rejection of a corneal graft.

Animals↗
PubMedDate not supplied

The clinical status of immunoscintigraphy with monoclonal antibodies in ocular melanoma.

A summary is given of data on the clinical experience with the anti-melanoma antibody 225.28S in ophthalmology and the tissue expression of the high molecular weight-melanoma associated antigen in choroidal melanoma. Results are discussed in relation to other detection methods for ocular melanoma currently employed by the ophthalmologist.

Antibodies, Monoclonal↗