Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The small peripheral blood CD3+ T cell population lacking both CD4 and CD8 surface antigens has been analyzed in the present study. Enriched CD3+4-8- populations were obtained by depletion with anti-CD4 or anti-CD8 monoclonal antibodies (mAb) and complement. The resulting populations contained greater than 99% CD2+ cells, whereas CD3+ represented approximately 50%. Virtually all of the cells were CD4-8- and did not react with the WT31 mAb, specific for a framework determinant of the alpha/beta T cell receptor (TCR). In order to analyze the molecular nature of CD3-associated molecules in CD3+WT31- populations, cells were stimulated with 0.5% phytohemagglutinin (PHA) for 24 h and expanded for an additional 7-14 days in interleukin 2 (IL 2). The resulting cells were greater than 95% CD3+ and expressed neither CD4/CD8 nor WT31 antigen. Cell surface iodination followed by cross-linking and immunoprecipitation with anti-CD3 mAb showed that CD3-associated molecules consisted of a major 45-kDa band and a minor band of 43 kDa. Thus, whereas CD3-associated molecules isolated from polyclonal CD3+WT31+ populations (expanded in IL 2 under the same culture conditions) appeared as diffuse bands, CD3-associated molecules isolated from CD3+WT31- populations displayed a homogeneous molecular mass. Northern blot analysis revealed the presence of mRNA for the TCR gamma chain whereas the mRNA for the alpha chain was mostly represented by a truncated (1.2 kb) form. Also small amounts of a nonproductive mRNA for the beta chain were detected. Freshly isolated CD3+WT31--enriched populations proliferated in response to PHA and concanavalin A, moreover, IL 2 was detected in the culture supernatants after cell stimulation. By applying culture conditions which allow virtually all T cells to undergo clonal expansion, approximately 1/3 CD3+WT31- were clonogenic. In addition, the large majority of proliferating microcultures lysed the K562 cell line and about half the natural killer (NK)-resistant fresh melanoma target cells. A large number of clones derived from CD3+WT31- enriched populations by limiting dilution has been further analyzed. More than 95% of the clones were CD3+4-8-WT31-; 12/15 clones analyzed in more detail displayed NK activity and 6/15 lysed melanoma cells; in addition, all lysed P815 target cells in the presence of PHA, thus indicating that all the clonogenic CD3+WT31- cells have a cytolytic potential.
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PMID:Human CD3+4-8-WT31- T lymphocyte populations expressing the putative T cell receptor gamma-gene product. A limiting dilution and clonal analysis. 295 93

Human thymocytes lacking both CD4 and CD8 differentiation antigens were prepared by treating total thymocyte suspensions with a mixture of anti-CD4 and anti-CD8 monoclonal antibodies and complement. The resulting populations contained less than 2% CD4+, CD8+ or WT31+ cells and variable percentages (less than 20%) of CD3+ cells. These cell populations were cultured in recombinant IL-2 in the presence of peripheral blood mononuclear cells as feeder cells. Cells underwent extensive proliferation accompanied by a progressive increase of CD3+ and CD8+ cells. On the other hand, appearance of neither WT31+, alpha/beta-positive T cell receptor (TCR), nor CD4+ cells could be observed in several independent experiments. Functional analyses revealed the appearance and the progressive increase of cytolytic activity against the natural killer (NK)-sensitive K562 cells as well as the NK-resistant fresh melanoma cells. Experiments of T cell cloning indicated that both the expression of CD8 and CD3 antigens and the appearance of cytolytic activity were consequent to cell maturation occurring at the level of CD4-CD8- non-cytolytic cell precursors. In these experiments, more than 30% of cells underwent clonal expansion and all the clonal progenies obtained displayed cytolytic activity and expressed the CD3+WT31- surface phenotype. The expression of CD8 was variable, whereas no CD4+ clones could be obtained. Cells expressing such surface phenotype are known to belong to the TCR gamma-positive T lymphocyte subset lacking the typical alpha/beta TCR and thus appear to be the only T cell type capable of in vitro proliferation and maturation under easily reproducible culture conditions.
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PMID:Interleukin-2-induced proliferation of CD4-CD8- human thymocytes. In vitro expression of CD3 and CD8 antigens and cytolytic activity. 296 37

Peripheral blood lymphocytes (PBL) of a patient with metastatic melanoma were cultured with autologous melanoma cells (Auto-Me) and recombinant interleukin 2 (IL-2) (MLTC-PBL). Thirty-five days later, when no cytotoxicity against Auto-Me or K562 was detectable, MLTC-PBL were cloned in the presence of Auto-Me, IL-2 (25 U/ml) and Daudi cells as feeder. Eighty-one growing clones were simultaneously screened for proliferative and cytotoxic activity to Auto-Me. Twenty-two clones proliferated in the presence of Auto-Me only, 29 in the presence of IL-2 only and 41 in the presence of Auto-Me plus IL-2; 12 clones showed cytotoxic activity against Auto-Me. Six clones expressed both cytotoxic and proliferative activity to Auto-Me. The phenotype of 6 proliferative clones tested was CD3+, CD4+, WT31+, CD8-, CD16-, Leu19-, whereas that of 2 cytotoxic-proliferative clones tested was CD3+, CD8+, Leu19+, WT31+, CD4-, CD16-. Specificity analysis of proliferative response of 6 clones and of cytotoxicity of 7 clones, tested on a panel of 14 different target cells, revealed a complex pattern of reactivity, each clone expressing a peculiar specificity. Our results suggest the possibility of isolating, from melanoma patients' PBL, T-cell clones with proliferative activity to Auto-Me and Auto-Me plus IL-2, and T-cell clones which apparently express both proliferative and cytotoxic activity to Auto-Me.
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PMID:Proliferative and/or cytotoxic activity of lymphocyte clones to autologous human melanoma. 296 67

CD4-CD8- human thymocytes were obtained by treating total thymocyte suspensions with anti-CD4 and anti-CD8 monoclonal antibodies (mAb) and complement. The resulting cell populations contained virtually no CD4+, CD8+ or WT31+ cells and 17-65% CD3+ cells. In addition, analysis of cell reactivity with delta-TCS-1 mAb (specific for the C gamma 2-encoded, nondisulfide-linked form of TcR gamma/delta), revealed the presence of a variable proportion of delta-TCS-1+ cells (the % of delta-TCS-1+ cells were lower than the percentage of CD3+ cells). Upon culture in recombinant interleukin 2 (IL2, in the presence of irradiated mononuclear cells), CD4-CD8- thymocytes underwent extensive proliferation. In addition, a progressive increase of CD8+ cells (but not of CD4+ or WT31+ cells) could be detected. Cells also progressively acquired cytolytic activity against K-562 or fresh melanoma cells. Fresh CD4-CD8- thymocytes were cloned under limiting dilution conditions. The cloning efficiencies were relatively high (1/3 cells); in addition, virtually all the clonal progenies obtained displayed cytolytic activity and expressed the CD3+WT31-delta-TCS-1+ surface phenotype. About half of the clones analyzed were CD8+, whereas none expressed CD4 antigens. We conclude that (a) only delta-TCS-1-reactive, TcR gamma/delta+ cells can be isolated from CD4-CD8- thymocytes cultured in IL2, and (b) the expression of CD8 antigen and of cytolytic activity reflects a true in vitro phenotypic change of CD8-, noncytolytic precursors (and not the preferential growth of few contaminating cells).
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PMID:Clonal analysis of CD4-CD8- human thymocytes expressing a T cell receptor gamma/delta chain. Direct evidence for the de novo expression of CD8 surface antigen and of cytolytic activity against tumor targets. 297 27

We analyzed the antigenic phenotype of lymphokine-activated killer (LAK) effector cells. Human blood lymphocytes were cultured for 3 days with 100 U/ml recombinant interleukin 2 (rIL 2), subpopulations isolated with monoclonal antibodies and a fluorescence-activated cell sorter (FACS) and assayed for cytotoxic activity against 51chromium labeled noncultured melanoma tumor cells. Initial experiments compared the LAK effector function of CD5+ T lymphocytes vs CD5- cells (predominantly CD16+ NK cells). The mean percent specific release at a 10:1 effector:target (E:T) ratio was 25% +/- 16 for CD5- cells, 10% +/- 6 for CD5+ cells, and 22% +/- 9 for unsorted cells. In contrast, when lymphocyte subpopulations were isolated before rIL 2 culture (LAK precursors), CD5- cells but not CD5+ cells developed LAK activity (28% +/- 12 vs 1% +/- 1, mean percent specific release, 10:1 E:T ratio), confirming our previous results showing that only CD16+ cells were LAK precursors. The discrepancy between LAK effector and precursor phenotypes suggested that LAK precursors acquired CD5 determinants during rIL 2 culture; however, double label immunofluorescence of rIL 2 cultured CD16+ cells showed that this was not the case. The data suggested that in the presence of other cell types, some T lymphocytes may develop LAK activity, but purified blood T lymphocytes do not develop LAK function when cultured with rIL 2 alone. We also analyzed LAK effector function in lymphocyte subpopulations defined by CD4 and CD8 antigens. The data showed that lymphocytes with a low density expression of CD8 and no expression of CD4 were enriched for LAK effector cells, whereas CD4+ and CD8- had less activity than unsorted cells. Lymphocytes with a high density expression of CD8 had activity similar to unsorted cells. We also assessed the contribution of Leu-7 (HNK-1) granular lymphocytes to LAK effector function. After culture with IL 2, lymphocytes were depleted of Leu-7+ cells by antibody and complement treatment and then were sorted into CD5+ and CD5- fractions. The cytotoxic activity of Leu-7-CD5+ cells was a mean 5% +/- 5 vs a mean 14% +/- 8 for the total CD5+ population (20:1 E:T ratio). The activity of Leu-7- CD5- was slightly less than the total CD5- fraction (21% +/- 9 vs 28% +/- 14, 10:1 E:T ratio). In conclusion, LAK effector function was highest in non-T cell (CD5- CD16+) populations and some activity was also present in T cell populations (CD5+ and predominantly Leu-7+).
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PMID:Human lymphokine-activated killer (LAK) cells: identification of two types of effector cells. 310 Jun 27

In these studies we investigated the phenotypic and functional characteristics of human rIL 2-activated killer cells (LAK). By FACS sorting we separated PBL into Leu-11- and Leu-11+ cell fractions and cultured them for 4 days in 100 U/ml rIL 2. Under these culture conditions, cells of the Leu-11+ fraction acquired a stronger LAK activity against fresh autologous or allogeneic melanoma cells as compared with Leu-11- cells or unfractionated PBL. To better characterize the cells responsible for this cytolytic activity, we directly cloned Leu-11+ and Leu-11- FACS-sorted cells in the presence of 1% PHA, irradiated spleen feeder cells, and rIL 2. From 6 to 10% of the Leu-11+ cells and from 42 to 66% of the Leu-11- cells plated gave rise to clonal progenies that were tested simultaneously for cytolytic activity against fresh melanoma cells and NK-sensitive K562 target cells in a 4-hr 51Cr-release assay. Most of the Leu-11+ microcultures lysed fresh melanoma target cells (35 out of 38 and 26 out of 34 in two separate experiments), whereas only a few clones derived from the Leu-11- cell fraction had this capability (four out of 45 and one out of 41). All the clones lysing fresh melanoma cells also efficiently killed K562 target cells, whereas other clones lysing only K562 could be found among Leu-11+ and Leu-11- clones. Nine clones expressing LAK activity were tested for their reactivity against a panel of different tumor target cells. All clones were able to lyse a broad panel of target cells including NK-sensitive and NK-resistant cultured or noncultured human tumor target cells, as well as mouse tumor cell lines. Surface marker analysis of 14 clones displaying LAK activity, all derived from Leu-11+ cells, showed that they were all T3 (CD3)-, whereas 10 out of 14 expressed the T11 (CD2) antigen and only four were weakly stained by an anti-T8 (CD8) mAb. All 14 clones expressed the T40 (CD7) T cell marker and DR and LFA-1 antigens. Cytolysis inhibition experiments performed on a rIL 2-activated Leu-11+ population and on two LAK cell clones, both expressing T11 antigen, showed that anti-LFA-1 but not anti-T11 mAb could inhibit cytolysis of freshly derived tumor target cells.
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PMID:Phenotypic and functional characterization of recombinant interleukin 2 (rIL 2)-induced activated killer cells: analysis at the population and clonal levels. 310 Jun 33

The in vitro development of tumor-specific cytotoxic T-cells from draining and tumor-involved lymph nodes obtained from melanoma patients were examined. Fresh draining or tumor-involved lymph node cells (LNC) demonstrate no significant cytotoxic activity against a variety of tumor targets including autologous melanoma. Natural killer cell (NK) activity is very low or absent in all of these specimens. Culture of the cells with irradiated autologous tumor and expansion in recombinant interleukin 2 (rIL-2) results in strong cytotoxicity for autologous tumor cells. The cultured cells are T-cells of mixed CD4 and CD8 phenotypes. Following restimulation with autologous tumor, these lines are capable of becoming specifically cytotoxic for autologous tumor as tested in direct killing and in cold target inhibition studies. The LNC yield from fresh specimens ranges from 1 X 10(7) to more than 1 X 10(9) cells averaging 5 X 10(8) cells. After the cells are cultured, we can achieve up to a 60-fold or more increase in cell numbers, that demonstrate strong cytotoxicity for melanomas. The potential for adoptive immunotherapy using such specifically sensitized cytotoxic T-cells of mixed phenotypes is discussed.
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PMID:Autologous lymph node cell-derived tumor-specific cytotoxic T-cells for use in adoptive immunotherapy of human melanoma. 326 Jan 24

Human T-cell populations specifically cytotoxic for autologous melanoma cells have been successfully generated from lymph node cells obtained from seven consecutive patients. The lymph node cells were stimulated in vitro with autologous irradiated melanoma cells; stimulation was repeated every 10-15 days at a tumor cell-to-lymphocyte ratio of approximately 1:20. Cytotoxic activity was assessed by a 4-hour 51Cr release assay. Mean lysis of autologous tumor cells was 47% at an effector-to-target cell ratio of 20:1, while mean lyses of the human myeloid leukemia cell line K562, allogeneic melanoma cells, and an osteosarcoma cell were 20%, 13%, and 11%, respectively. There was no lysis of autologous fibroblasts, fresh lymphocytes, or phytohemagglutinin-stimulated blasts. Three grades of specificity developed sequentially. In grade I, lysis of autologous tumor cells exceeded lysis of allogeneic tumor cells but did not exceed lysis of K562 cells. In grade II, lysis of autologous tumor cells exceeded lysis of K562 cells and all allogeneic tumor cells tested. In grade III, potent lysis of autologous tumor cells (greater than 40%) exceeded lysis of K562 cells and of all allogeneic tumor cells tested. All seven lymphocyte populations reached or exceeded grade I. Six reached or exceeded grade II. Two progressed to grade III. The generated cells were T cells, as determined by phenotypic analysis with flow cytometry. CD4+ cells and CD8+ cells accounted for 83%-100% of the cells. CD8+ T cells were separated from CD4+ T cells by panning with OKT8 and OKT4 antibodies. The resulting CD8-enriched and CD4-enriched populations were compared as effectors in cytotoxicity assays. The results suggest that the cell responsible for lysis of autologous tumor cells is CD8+. The methods used in this study have repeatedly resulted in the successful generation of cytotoxic T lymphocytes specifically cytotoxic for autologous melanoma cells; it is suggested that these cells have potential application for adoptive immunotherapy of melanoma.
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PMID:Human cytotoxic T cells specific for autologous melanoma cells: successful generation from lymph node cells in seven consecutive cases. 326

A successful antitumor T cell immune response involves induction, recruitment, and effector function of T cells. While B7/BB1 is known as a major costimulatory molecule in the induction of T cell responses, its role in T cell recruitment and effector function is still unclear. In this study, we show that introducing a major costimulatory molecule B7/BB1 into a major histocompatibility complex class II-negative tumor cell line, J558, results in a drastic reduction of its tumorigenicity. The tumor rejection depends on CD8 T cells but not CD4 T cells. However, unlike the previous reports on melanoma cell lines, B7/BB1-transfected J558 cells fail to induce cross-protection against parental J558 cells. The B7/BB1-transfected (J558-B7), but not untransfected J558 cells (J558-Neo) induce a CD8 T cell-dominant inflammatory response, and the T cells isolated from the tumor infiltrating lymphocytes (TIL) are polyclonal in terms of their T cell receptor V beta usage. Most surprisingly, the freshly prepared TIL have a potent, CD8 T cell-mediated cytotoxicity on tumor cells without any in vitro stimulation. The cytotoxic T lymphocyte (CTL) activity can be blocked by anti-CD8 monoclonal antibody (mAb). Interestingly, the CTL lyse J558-B7 about 10- to 80-fold more efficiently than untransfected J558-Neo cells. This preferential lysis cannot be attributed to recognition of B7/BB1-derived antigen by the T cells. This finding, together with the lack of the cross-protection between the J558-B7 and J558-Neo, suggests that B7/BB1 can also function at the effector phase of CTL responses. This notion is confirmed by our findings that the lysis of J558-B7 can be blocked by anti-B7 mAbs. Taken together, our results indicate that not only can the B7/BB1 molecule function as a costimulatory molecule at the initiation of immune response, it can also play a major role in T cell recruitment and effector function. This conclusion has significant implications for immunotherapy of tumors.
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PMID:T cell costimulation by B7/BB1 induces CD8 T cell-dependent tumor rejection: an important role of B7/BB1 in the induction, recruitment, and effector function of antitumor T cells. 751 83

The effect of cytokines with human recombinant interleukin-2 (rIL-2) on cytolytic T cell (CTL) generation was studied. Lymphocytes were isolated from involved lymph nodes of melanoma patients and expanded in medium containing rIL-2 alone or in combination with other human cytokines (rIL-1, rIL-4, rIL-6, and recombinant human tumor necrosis factor-alpha (rTNF alpha)). Lymphocytes incubated with rIL-2 alone did not grow, whereas addition of the other cytokines augmented IL-2-mediated lymphocyte proliferation. In all cultures, the majority of expanded lymphocytes were CD3+, CD56- T cells. Lymphocytes cultured with rIL-1, rIL-2, rIL-4, and rIL-6 exhibited cytolytic activity specific for autologous melanoma, which increased during the culture period (24.08 and 58.18% at 16 and 30 days in culture, respectively) without detectable changes in cell surface phenotype and remained high even after 100 days in culture. Moreover, the cytolytic activity was inhibited by monoclonal antibodies (mAbs) against HLA-class I, CD3, and CD8 molecules but not by mAbs against HLA-class II or CD4 molecules. Lymphokine-activated killer (LAK) activity was detected in lymphocytes cultured with rIL-1, rIL-2, and rIL-6 in the presence or absence of rTNF alpha. These data indicate that lymphocytes derived from melanoma-invaded lymph nodes and cultured in the presence of rIL-1, rIL-2, rIL-4, and rIL-6 offers an efficient system to expand CD8+ CTLs with HLA-restricted cytolytic specificity against autologous tumor cells.
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PMID:In vitro expansion of tumor-specific, HLA-restricted human CD8+ cytolytic T lymphocytes. 751 62


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