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J Hansson

Publications and source records attributed to J Hansson.

At least 73 records · Page 4Linked to original sources
PubMed1996

Prognostic value of serum analyses of S-100 beta protein in malignant melanoma.

S-100 protein was first described in the central nervous system but is also present in malignant melanoma cells. Immunohistochemical detection of S-100 is widely used in the histopathological diagnosis of malignant melanoma. In the present study serum levels of S-100 beta protein were measured in 643 patients with cutaneous malignant melanoma. An immunoradiometric assay with three monoclonal antibodies against bovine S-100 protein beta subunit was used. At the time of blood sampling 553 patients were in clinical stage I, 24 in clinical stage II and 66 in clinical stage III. The overall survival rate was strongly associated with serum levels of S-100 protein. The observed/ expected death ratio was markedly increased with increasing levels of S-100 beta (P < 0.001). A fivefold increase in relative hazard was indicated by a value of S-100 beta exceeding 0.6 microgram/l (P < 0.001) and when this cut-off level was used S-100 beta had additional prognostic value independent of clinical stage (P < 0.001). Our data strongly suggest that S-100 beta in serum is an independent prognostic marker that may be useful in identifying high-risk cases and monitoring response to therapy in patients with malignant melanoma.

Adolescent↗
PubMed1996

Increased cisplatin sensitivity of human fibroblasts from a subject with inherent glutathione deficiency.

Fibroblasts from an individual with 5-oxoprolinuria are deficient in glutathione (GSH) as compared to cells from a healthy sibling. Glutathione transferase (GST) levels also differ for some isoenzymes: GSH deficient cells have more GST A1-1, but lack GST M1-1. However, the contents of the quantitatively dominating isoenzyme GST P1-1 show no significant difference. While there is equal sensitivity to ultaviolet irradiation (UV), the GSH deficient cells are more sensitive to cisplatin, carboplatin and melphalan. Depletion of GSH with buthionine sulfoximine sensitizes the normal fibroblasts to these drugs. Only slightly more cisplatin-induced DNA cross-links are detected in the GSH deficient cells, and there is no difference in the removal of DNA cross-links. Similar amounts of DNA strand breaks are seen in normal and GSH deficient cells after UV exposure, but there is a reduced rates of resealing of strand breaks in GSH deficient cells. The main conclusion from the studies of these fibroblasts is that GSH plays a significant role in the cellular resistance to cytostatic drugs such as platinum compounds and melphalan.

Cell Line↗
PubMed1995

Antibody-targeted superantigens are potent inducers of tumor-infiltrating T lymphocytes in vivo.

Recruitment of antigen-specific tumor-infiltrating lymphocytes (TILs) is a major goal for immunotherapy of malignant tumours. We now describe that T-cell-activating superantigens targeted to a tumor by monoclonal antibodies induced large numbers of pseudospecific TILs and eradication of micrometastases. As a model for tumor micrometastases, syngeneic B16 melanoma cells transfected with the human colon carcinoma antigen C215 were injected intravenously into C57BL/6 mice and therapy with an anti-C215 Fab fragment-staphylococcal enterotoxin A (C215Fab-SEA) fusion protein reacting with the C215 antigen was initiated when visible lung metastases were established. More than 90% reduction of the number of lung metastases was observed when mice carrying 5-day-old established lung metastases were treated with C215Fab-SEA. The antitumor effect of C215Fab-SEA was shown to be T-cell-dependent since no therapeutic effect was seen in T-cell-deficient nude mice. Depletion of T-cell subsets by injection of monoclonal antibody demonstrated that CD8+ cells were the most prominent effector cells although some contribution from CD4+ cells was also noted. C215Fab-SEA treatment induced massive tumor infiltration of CD4+ and CD8+ T cells, while only scattered T cells were observed in untreated tumors. SEA treatment alone induced a slight general inflammatory response in the lung parenchyme, but no specific accumulation of T cells was seen in the tumor. TILs induced by C215Fab-SEA were mainly CD8+ but a substantial number of CD4+ cells were also present. Immunohistochemical analysis showed strong production of the tumoricidal cytokines tumor necrosis factor alpha and interferon gamma in the tumor. Thus, the C215Fab-SEA fusion protein targets effector T lymphocytes to established tumors in vivo and provokes a strong local antitumor immune response.

Animals↗
PubMed1995

Superantigen-induced anergy in cytotoxic CD8+ T cells.

This study describes the use of bacterial superantigens to investigate the mechanisms governing peripheral tolerance in CD8+ T cells. Administration of superantigens to mice activates T cells to proliferation, cytokine production, and cytotoxicity, but responding cells subsequently enter a state of hyporesponsiveness or are deleted. Superantigen-induced inactivation has so far mainly been demonstrated for CD4+ T cells. Injection of amounts of the superantigen staphylococcal enterotoxin A (SEA) that are optimal for T cell activation and which induce anergy in CD4+ T cells result in preserved responsiveness in CD8+ CTLs. In contrast, we found that intravenous injection of low concentrations of SEA induced a profound down-regulation of the cytotoxic function in SEA-reactive CD8+ TCR V beta 11+ T cells. No reduction in the number of CD8+V beta 11+ T cells was found, suggesting that anergy and not deletion is the main mechanism for the observed cytotoxic hyporesponsiveness. The cytotoxic anergy was evident 2 days after low-dose priming and remained present 4 wk later, indicating a rapid induction phase and long-lasting persistence. The anergized CD8+ T cell subset expressed lower levels of the alpha-(CD11a) chain of the cell adhesion molecule lymphocyte function-associated Ag 1 (LFA-1) and failed to mediate cytotoxicity, but retained the capacity to proliferate, express IL-2R, produce IFN-gamma, and express granzyme mRNA, which imply a partial defect in TCR-transduced signals. Taken together, these findings suggest that there is a biphasic stimulus-dependent threshold for acquiring responsiveness or anergy in CD8+ T cells.

Animals↗
PubMed1995

Distinct splicing of CD45 mRNA in activated rat gamma delta cytotoxic T lymphocytes.

Previous studies have demonstrated tumor- and allo-specific cytotoxic gamma delta T lymphocytes in rats. In this report we define the surface phenotype of these T cell receptor (TCR) gamma delta+ T cells and demonstrate distinct CD45 mRNA splicing in activated gamma delta cytotoxic T lymphocytes (CTL). gamma delta T lymphocytes in the blood and the peritoneal cavity were TCR alpha beta-CD3+CD8 alpha+CD45RC+ but expressed variable levels of LFA-1 molecules. Normal peritoneal gamma delta T lymphocytes, peritoneal gamma delta T cells from rats injected with the bacterial superantigen staphylococcal enterotoxin A (SEA) as well as gamma delta T lymphocytes in peripheral blood were all LFA-1low. Peritoneal gamma delta T cells from tumor-, and allo-sensitized rats were either LFA-1low or LFA-1high and specific cytotoxicity was highly enriched in the LFA-1high subset. No cytolytic activity against SEA-presenting cells was recorded in gamma delta T cells from SEA-injected rats. Different isoforms of CD45 in T cells are generated by alternative mRNA splicing of exons 4, 5, 6 (or A, B and C, respectively) and the recently described alternate exon 7. CD45 splicing in sorted gamma delta T cells was evaluated utilizing reverse transcription polymerase chain reaction. Normal peritoneal gamma delta T cells expressed exon(578), exon(678), exon(78) and the extensively spliced exon(8) variant. Peritoneal gamma delta T cells from rats sensitized with irradiated syngeneic tumor cells, allogeneic cells or bacterial superantigen SEA as well as gamma delta T lymphocytes in peripheral blood contained the full-length exon(45678), as well as the exon(5678), exon(578), exon(678) and exon(78) splicing products. Notably, the exon(8) variant was also seen in peritoneal gamma delta T cells of SEA-sensitized rats. Sorted tumor-specific LFA-1high gamma delta CTL expressed exon(45678), exon(5678), exon(578), exon(678) and exon(78) CD45 splicing products whereas the non-cytolytic LFA-1low gamma delta T cell subset also contained exon(8) variant. In summary, it is concluded that antigen-specific TCR gamma delta+ CTL express high levels of LFA-1 and that the splicing machinery in these cytolytic cells favors expression of the exon(45678) and exon(5678) CD45 splicing products whereas the exon(8) variant is lost. TCR alpha beta+ CTL express high levels of LFA-1 but are devoid of the full-length exon(45678) splicing product. The different CD45 splicing patterns found in alpha beta CTL and gamma delta CTL indicate different molecular requirements in respect to CD45 during activation and differentiation of these T lymphocyte subsets.

Alternative Splicing↗
PubMed1995

O6-methylguanine-DNA methyltransferase activities in biopsies of human melanoma tumours.

Tumour samples obtained from one primary melanoma and several lymph node and skin metastases were analysed for O6-methylguanine-DNA methyltransferase (MGMT) activity. While lymph node and skin metastases had similar average MGMT activity, the variance was significantly higher in lymph node metastases. Variability in MGMT activity was frequently observed in different metastases in the same individual and to a lesser extent within metastases.

Biopsy↗
PubMed1995

Apoptosis and c-jun induction by cisplatin in a human melanoma cell line and a drug-resistant daughter cell line.

Cisplatin resistance was developed in the human melanoma cell line RPMI8322 by repeated short-term exposures to cisplatin. The most resistant daughter cell line, RPMI8322/CDDP-300, was 4-fold resistant to cisplatin, and partially cross-resistant to carboplatin, melphalan and UV, but not to BCNU. RPMI8322/CDDP-300 cells showed less apoptosis after cisplatin than the parental cells. The cisplatin resistance was not paralleled by a similar reduction in cellular cisplatin accumulation or DNA cross-links in RPMI8322/CDDP-300 cells, and these cells exhibited no increase in cellular glutathione or in mRNA encoding the DNA excision repair protein ERCC1 and XPB. Induction of c-jun mRNA by cisplatin was considerably lower in RPMI8322/CDDP-300 cells than in RPMI8322 cells, consistent with the possibility that c-jun induction may be involved in a pathway that triggers apoptosis after exposure to DNA damaging agents. However, c-jun induction is not necessary for apoptosis, since cisplatin also induced apoptosis in A14 rat embryo fibroblasts, cells in which the c-jun gene is deleted.

Animals↗
PubMed1995

Expression of CD11a and CD45R isoforms defines distinct subsets of CD8+ TCR alpha beta and TCR gamma delta CTL in vivo.

Intraperitoneal immunization of rats with a syngeneic lymphoma and allogeneic leukocytes induced enrichment of antigen-selective TCR alpha beta+ and TCR gamma delta+ CTL. The peritoneal cavity seems to be a suitable site for enrichment of antigen-selective CTL, since the induced effector cells executed strong cytotoxicity without any requirement for in vitro reactivation. Tumor-selective CTL expressed high cell surface levels of CD45RC, allogeneic CTL expressed a variable level of CD45RC, while SAg-reactive CTL had low CD45RC expression. CTL with tumor and allogeneic selectivity as well as SAg-induced CTL all expressed the LFA-1high phenotype, suggesting that upregulation of LFA-1 is a hallmark for in vivo activated CTL. RT-PCR analyses showed that all CD8+TCR alpha beta+ CTL lost expression of CD45R exon 4 mRNA, which is compatible with the view that effector/memory T cells are CD45RA-. In contrast, TCR gamma delta+ CTL retained the CD45RA phenotype but showed a down-regulation of CD45R exon 8 mRNA. Since isoforms of the CD45 tyrosine phosphatase have been reported to differentially affect T-cell activation, the unique CD45R splice pattern observed in TCR alpha beta+ and TCR gamma delta+ CTL implies that CD45R may influence the TCR signal transduction distinctly in various effector CTL subsets.

Animals↗
PubMed1995

The expression of glutathione transferase isoenzymes in human malignant lymphoma biopsies.

Glutathione transferase (GST) activity as well as the expression of different classes of GST isoenzymes were studied in 14 lymphoma biopsies. The GST activity measured with 1-chloro-2,4-dinitrobenzene as a substrate, varied almost 9-fold. The expression of GSTs classes Pi, Alpha and Mu was studied by immunoblotting using antibodies against human GSTs. All lymphoma samples displayed high levels of class Pi GST. Class Alpha and Mu GSTs expression varied from not detectable to high. The observations were confirmed by quantitation of the three classes of GST with an ELISA technique. Nine of the patients were treated with bifunctional alkylating agents. A correlation between a clinical complete response to chemotherapy and low expression of GST Alpha was noted (p < 0.02).

Alkylating Agents↗
PubMed1994

Interleukin 10 pretreatment protects target cells from tumor- and allo-specific cytotoxic T cells and downregulates HLA class I expression.

Interleukin 10 (IL-10) is a cytokine with a variety of reported effects including inhibition of monocyte major histocompatibility complex (MHC) class II-dependent antigen presentation, type 1 helper T cell cytokine production, and inhibition of T cell proliferation. Herein we report the effect of IL-10 pretreatment on antigen presentation to tumor- and allo-specific CD8+ cytotoxic T lymphocytes (CTL). Prior incubation of human melanoma cells with recombinant IL-10 (rIL-10) for 48-72 h resulted in a dose-dependent, up to 100% inhibition, of autologous CTL-mediated, HLA-A2.1-restricted, tumor-specific lysis. Allo-specific CTL cytotoxicity against Epstein-Barr virus-transformed lymphoblastoid cell lines (LCL) was also inhibited, demonstrating a protective effect also on lymphoid cells. In contrast, IL-10 pretreatment of allogeneic LCL or K562 targets had either no effect or slightly enhanced cytotoxic activity mediated by freshly isolated or IL-2-activated natural killer cells. Flow cytometric analysis with monoclonal antibodies against HLA-A2, or nonpolymorphic determinants of MHC class I proteins, revealed a 20-50% reduction in cell-surface expression, whereas intercellular adhesion molecules 1, and 2, and lymphocyte function-associated antigen 3 levels were not affected. In addition, relative to untreated target cells, IL-10 pretreated tumor cells were unaltered in their capacity to affect CTL-mediated lysis by cold target inhibition, demonstrating that the effect of IL-10 is unrelated to the initial binding of CTL to their targets. These results are compatible with an effect of IL-10 on the MHC class I antigen presentation pathway, and suggest a novel mechanism of immune tolerance, based on escape from CTL-mediated tumor and allo-transplant rejection.

Antibodies, Monoclonal↗
PubMed1994

Similar toxic effect of 1,3-bis(2-chloroethyl)-1-nitrosourea on lymphocytes from human subjects differing in the expression of glutathione transferase M1-1.

Sixteen healthy donors were investigated for the presence or absence of glutathione transferase (GST) M1-1 in lymphocytes by immunodetection with polyclonal antibodies against human GST M1-1. Nine out of 16 individuals (56%) were categorized as GST M1-1 positive. Phytohaemagglutinin stimulated lymphocytes from GST M1-1 positive and negative donors were treated with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and compared regarding inhibition of [3H]thymidine incorporation as a measure of cytotoxicity. No significant differences in the effect of BCNU were observed between the two groups, indicating that GST M1-1 is not an important resistance factor for BCNU.

Carmustine↗
PubMed1994

Deficient repair of cisplatin-DNA adducts identified in human testicular teratoma cell lines established from tumours from untreated patients.

Germ cell tumour lines appear generally more sensitive in vitro to cisplatin than other cultured cell lines, reflecting their clinical responsiveness. We proposed (Cancer Res 1988, 48, 3019-3024) that cisplatin hypersensitivity, expressed by a testicular teratoma line (SuSa), might be explained by an inability to repair platinated DNA. We have now quantitated cisplatin cytotoxicity by clonogenic assay, and platinum (Pt)-DNA adduct formation and removal immunochemically in four other testicular teratoma continuous cell lines (GCT46, GCT27 clone 4, H32 and H12.1), all established from tissue from non-drug-treated patients. For 1-h in vitro drug exposures, the cisplatin concentration required to reduce survival by 50% (IC50) ranged from 0.09 to 0.42 micrograms/ml (0.3-1.4 microM). Immediately following a 1-h exposure to 5 mu/ml cisplatin, total cellular platination levels ranged from 4.5 to 36.8 fmol Pt per microgram DNA, with lower platination occurring in the most sensitive lines. Following an 18-h post-treatment incubation period, the levels of the major cis-Pt-(NH3)2d(pGpG) (Pt-GG) adducts were not significantly reduced in any of the four lines, indicating a general deficiency in either the rate or extent of removal of these lesions. Deficient removal of the cis-Pt-(NH3)2d(pApG) adducts was also noted in two of the lines. DNA polymerase beta gene expression was comparable in all the tested testicular lines established from previously untreated patients, but markedly lower than that identified in the 833K testicular line, established from a drug-treated patient and identified earlier as proficient in Pt-GG adduct removal (Cancer Res 1988, 48, 3019-3024). Expression of the DNA excision repair genes ERCC-1 and XPBC/ERCC-3 was not significantly different in any of the five lines tested, including the 833K cell line. These data provide evidence of the apparent inability of testicular cell lines, derived from untreated tumours, to repair the major platinum-DNA intrastrand crosslinks, and so provide a biological basis for their hypersensitivity to cisplatin.

Cell Survival↗
PubMed1994

Gene expression in X-irradiated human tumour cell lines expressing cisplatin resistance and altered DNA repair capacity.

Previous studies have indicated that excision repair genes, such as ERCC1, or early response genes, such as c-fos, may play a significant role in regulating cellular responses to cisplatin (CDDP) by mediating DNA synthesis and repair pathways. This present study aimed to determine whether altered gene expression mediated CDDP resistance expressed in two human tumour sublines following their in vitro exposure to fractionated X-irradiation, not to the drug itself. These sublines, designated SuSa/DXR10 and SKOV-3/DXR10, established respectively from a testicular teratoma cell line (SuSa) or an ovarian carcinoma cell line (SKOV-3), expressed stable 3.1- and 2-fold levels of CDDP resistance, as judged by clonogenic assay. Both sublines expressed c-fos, c-myc and thymidylate synthase (TS) RNA constitutively, but at comparable levels to their parental counterparts. Whilst the ovarian carcinoma cells inherently expressed markedly higher levels (30- to 50-fold) of the excision repair gene ERCC1 than the teratoma cells, only the teratoma DXR10 subline showed an increased level of expression of ERCC1 mRNA relative to their parental cells. Expression of the ERCC3/XPB gene encoding a repair helicase, however, was similar in all the lines tested. The results suggest that CDDP resistance may be mediated by different mechanisms in these DXR10 sublines from those previously identified in drug-selected CDDP-resistant human ovarian A2780/DDP cells.

Cisplatin↗
PubMed1994

Different types of in vivo induced cytolytic T lymphocytes are all LFA-Ihigh and lack CD45 exon 4 (CD45RA) but show distinct CD45RC profiles.

Due to alternate mRNA splicing of exons 4, 5 and 6 (or A, B and C respectively), the CD45 cell surface glycoprotein is structurally heterogeneic in lymphoid cells of different lineage or stage of activation. Previous studies show that in vivo induced allo- and superantigen reactive rat cytolytic T lymphocytes (CTL) preferably belong to the CD45RClow subset, whereas tumour selective CTL express high amounts of CD45RC cell surface molecules. In this paper, reverse transcription polymerase chain reaction technique (RT-PCR) was utilized to evaluate CD45 isoform expression of rat lymphoid cells and in vivo activated rat CTL with distinct specificity and CD45RC profile. Cells from lymphoid organs expressed six CD45 mRNA isoforms, exon(45678), exon(5678), exon (578), exon(678), exon(78) and a novel extensively spliced exon(8) variant. In vivo activated TCR alpha beta + CD8+ cells sorted as CD45RClow expressed exon(78), exon(578) and exon(8), whereas TCR alpha beta + CD8+CD45RChigh cells expressed exon(78), exon(578), exon(5678) and full-length exon(45678). Triple-colour staining indicated high expression of LFA-1 in the cytotoxic CD45RCintermediate and CD45RClow cells, and low expression of LFA-1 in CD45RChigh non-cytotoxic cells from allo- and superantigen activated rats. In contrast, tumour activated TCR alpha beta +CD45RChigh cells were divided in LFA-1high and LFA-1low subsets, and sorting of these subsets revealed that tumour-selective cytotoxicity was confined to the LFA-1high effector cell subset. Furthermore, it was evident that the LFA-1high effector cell subset expressed high levels of exon(5678), exon(578) and exon(78) isoforms and, in contrast to the LFA-1low subpopulation, lacked expression of exon 4 containing full-length CD45 mRNA transcript.(ABSTRACT TRUNCATED AT 250 WORDS)

Alternative Splicing↗
PubMed1994

Normal reactivation of plasmid DNA inactivated by UV irradiation by lymphocytes from individuals with hereditary dysplastic naevus syndrome.

Hereditary dysplastic naevus syndrome (DNS) is a familial disorder characterized by dysplastic naevi and an approximately 85-fold increased risk of developing malignant cutaneous melanoma. Cell lines from individuals with DNS have shown hypermutability following exposure to UV irradiation. The cause of this hypermutability is unknown, and no DNA repair defect has been identified. We have studied the capacity of lymphocytes from individuals with DNS to reactivate the chloramphenicol acetyltransferase gene in transfected plasmids that had been inactivated by UV irradiation. We found no difference in plasmid reactivation between lymphocytes from individuals with DNS and those obtained from healthy control persons matched for sex, age and smoking habits. This finding indicates that DNS is not associated with a significant quantitative defect in nucleotide excision repair of DNA.

Adult↗
PubMed1994

Estramustine binding protein in primary tumours and metastases of malignant melanoma.

The presence of estramustine binding protein (EMBP), a 54 kD cytosolic glycoprotein, which is distinct from the estrogen receptor, was investigated in a pilot study of primary malignant melanomas and their metastases. In 11 primary melanomas EMBP was demonstrated by immunohistochemistry. The percentage of positive melanoma cells ranged between 11-91% with a mean of 57%. Radioimmunoassay on metastatic tissue revealed significant amounts of EMBP, with values ranging between 0.6-4.2 with a mean of 1.6 ng/mg protein. A high number of cells with a positive stain for EMBP in the primary tumours was significantly correlated to a short interval between diagnosis and the occurrence of metastases. Presence of EMBP in malignant melanoma may have prognostic significance and the role of hormone-linked cytostatic drugs in the treatment of this disease needs further investigation.

Adult↗
PubMed1994

Elective lymph node dissection in stage I cutaneous malignant melanoma of the head and neck. A report from the Swedish Melanoma Study Group.

The effect of elective lymph node dissection in patients with cutaneous malignant melanoma of the head and neck was investigated in a retrospective study. Of 517 patients in clinical stage I, 84 underwent elective dissection of the ipsilateral neck lymph nodes. In six of these patients, lymph node metastases were demonstrated at histopathological examination. There was a slight reduction in the incidence of recurrent disease in the regional lymph nodes in the group of patients who had undergone elective lymph node dissection, but this difference was not statistically significant. No significant differences were seen between the two groups regarding overall survival of disease-related survival.

Aged↗