摘要:

Summary:Major histocompatibility complex (MHC) class I antigens (Ag), particularly human lymphocyte antigen (HLA)-A2, have been shown to function as restriction elements in human cytotoxic T lymphocyte recognition of tumor. This study was undertaken to determine the function of non-A2 MHC class I Ag in tumor recognition by tumor-infiltrating lymphocytes (TILs) cultured from six melanomas, and to find evidence for shared or unique tumorassociated Ag. Four predominantly CD8+and two mixed CD4+, CD8+population TIL cultures were tested for lysis in short-term51Cr-release assays against a panel of targets including 29 fresh melanomas, 2 fresh sarcomas, 11 cultured melanoma lines, and 14 nonmelanoma cell lines derived from HLA-typed patients. All six melanoma TILs lysed the autologous melanoma. Two of three TILs from HLA-A2+patients lysed allogeneic melanomas matched for HLA-A2, giving evidence for shared tumor Ag; one of these TILs also used HLA-B44 as a restriction element. The third HLA-A2+TIL lysed autologous melanoma but not autologous Epstein-Barr virus-transformed B cells nor 14 HLA-A2 matched allogeneic melanomas, suggesting the possibility of a unique tumor Ag in this system. The three HLA-A2- TILs each lysed multiple HLA-matched melanomas, using HLA-A24, HLA-A31, and HLA-Cw7 as restriction elements. Blocking of autologous and allogeneic melanoma lysis by TILs with mAb w6/32 (anti-MHC class I) and anti-CD3, as well as cold target inhibition assays, confirmed that specific interaction of the T-cell receptor with MHC class I Ag and the relevant tumor Ag on the target cell surface is required for tumor lysis. These data provide evidence for specific recognition of shared melanoma Ag by human TILs.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:To evaluate whether cells selected for doxorubicin resistance were cross-resistant to tumor necrosis factor, the effects of doxorubicin and recombinant human tumor necrosis factor-α (TNF) on doxorubicin-sensitive (WT) and 40-fold doxorubicin-resistant (40F) MCF-7 cell proliferation were assessed. The median dose (MD) for doxorubicin was 14.5 nMfor WT cells and 474 nMfor 40F cells. The MD for TNF was 0.18 nMfor WT cells, while 40F cells were highly resistant to TNF concentrations up to 60 nM. Doxorubicin and TNF in combination were synergistic against WT cells, but not 40F cells. Glutathione depletion by buthionine sulfoxamine sensitized WT cells threefold to TNF, with no change in their response to doxorubicin, while 40F cells showed a twofold increase in doxorubicin sensitivity, with no apparent change in their resistance to TNF. No significant differences in TNF receptor number, Kd, or capacity for TNF internalization were noted between the two cell types. WT cells produced a single 15 kDa TNF degradation product, while the 40F cells produced three lower molecular weight degradation products. We conclude that cross-resistance to TNF in doxorubicin-resistant MCF-7 cells may be explained in part by altered TNF degradation.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

SummaryThis report describes a rapid, reproducible in vitro bioassay to quantitate the cytotoxic activity of human tumor necrosis factor-α using a human rather than murine cell line in the absence of metabolic inhibitors. The target cells are BT-20 (breast carcinoma) cultured at 39°C in the presence of recombinant human tumor necrosis factor-a (rHuTNF-α) in 96-well microtiter plates for 2 days. Cytotoxicity is measured by the crystal violet dye uptake of the remaining viable cells. This bioassay is sensitive to 1.5 ng/ml of rHuTNF-α, with an assay range to 130 ng/ml. Samples spiked into human plasma are measurable from 0.5 to 150 ng/ml. The specificity of this cytotoxic effect on the BT-20 cell line was demonstrated using rHuTNF-α neutralizing antibodies. A panel of cytokines including interferons, interleukins, and tumor necrosis factors was also analyzed using this assay system. Of the cytokines assayed, only recombinant murine tumor necrosis factor-α and recombinant human tumor necrosis factor-β demonstrated measurable cytotoxic activity when assayed independently, while recombinant human interferon-7 was the only cytokine to demonstrate greater than additive activity in combination with rHuTNF-α. The simplicity and reproducibility of this assay on a human cell line makes it useful for the routine determination of the biological activity of human tumor necrosis factor-α.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:Earlier studies have shown direct effects of interleukin-1 (IL-1) on isolated pancreatic islets. Coculture of isolated rat pancreatic islets with human rIL-1β for 6 days resulted in dose-dependent cytotoxicity (up to 100%) and suppression of insulin secretion (up to 88.5%). The cytotoxic effects of rIL-1β were blocked by the simultaneous presence of a naturally occurring 6- 9-kilodalton (kDa) inhibitor of IL-1-induced T-cell proliferation. However, the ability of rIL-1β to suppress insulin secretion was not blocked by the 6-9-kDa inhibitor of IL-1 activity. This IL-1 inhibitor is produced by mononuclear cells and is resistant to pH 2, sensitive to heating at 56°C for 30 min, has a pi of 4.5-5.6, and appears to be different from other recognized IL-1 inhibitors in both composition and mechanism of action. Unlike this IL-1 inhibitor, a monoclonal antibody specific for rIL-1β was able to neutralize both the islet cytotoxic and insulin modulatory effects of rIL-1β. These results demonstrate the use of an IL-1 inhibitor to prevent at least one mechanism of islet destruction, and suggest separate pathways for IL-1-mediated islet cytotoxicity and suppression of insulin secretion.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:The effectiveness of “standard” lymphokine-activated killer (LAK) cells, recovered after 6 days, and of “standard” adherent LAK (ALAK) cells, recovered after 14 days of culture in the presence of recombinant interleukin-2 (rIL-2) from peripheral blood lymphocytes of 21 healthy donors, was assessed through comparison of their proliferation, surface markers, cytotoxic activity, lymphokine production, and antitumor activity. In the presence of rIL-2, plastic adherent precursors of A-LAK cells proliferated much better than those of “standard LAK” cells and expanded even more than 300-fold. However, the final cell recovery of A-LAK was always lower because of their very few precursors, and the total lytic units (LUs) generated in A-LAK cultures were always lower for the same reason. On the other hand, the lytic activity of each A-LAK cell was always higher than that of a LAK cell. This was particularly evident on day 6 of culture. Removal of nonadherent cells after the first 24 h culture resulted in a significant enrichment in CD3¯CD56+and CD8+CD56+cells in A-LAK cells, with a marginal number of CD4+cells. A significant direct correlation between LUs and A-LAK CD3¯CD56+percentage was found. In the presence of rIL-2, A-LAK cells produced higher amounts of tumor necrosis factor-α and interferon-γ than LAK cells, while only A-LAK cells produced IL-iβ and small amounts of IL-4. Neither LAK nor A-LAK produced IL-2. In the absence of injections of IL-2, LAK and A-LAK cells were equally able to inhibit the growth of a human T-cell lymphoma in immunosuppressed nude mice.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:The liver macrophage population was fractionated according to cell size into three subpopulations by means of elutriation centrifugation. The total liver macrophage population and the three subpopulations were cultured and exposed to the immunomodulators muramyl dipeptide (MDP), in a free or liposome-encapsulated form, and/or lipopolysaccharide (LPS). The tumor cytotoxic activity thus induced in the populations, the preservation of this activity, and the response to a second stimulus were studied. The in vitro induced cytolytic activity was determined by a radioactivity release assay, using C26 colon adenocarcinoma cells, labeled with [methyl-3H]thymidine, as target cells. MDP or LPS readily activated the total macrophage population in maintenance culture to a tumor cytotoxic state during the first 2 days after isolation. Four days after isolation, the activation induced with both MDP and LPS was strongly reduced. The small to intermediate-size macrophages could be activated to tumor cytotoxic activity with MDP for up to 3 days and with LPS for up to 4 days in culture. The large-size macrophages could only be activated up to day 2 in culture with MDP or LPS or both. The combination of MDP and LPS, however, induced all cell populations in a synergistic way to become cytolytic for up to 4 days in culture. With free MDP as an activator, the activated state decayed within 1 day to almost zero levels, but less rapidly in the small cells than in the large cells. With liposome-encapsulated MDP, the activated state was preserved considerably longer, except in the largest cells. A second exposure of the macrophages to LPS and MDP, either separately or in combination, 48 h after the first exposure to the same agent(s), i.e., at a time when the initial activity had fully decayed, showed a considerable reduction in the responsiveness in the small to intermediate-size cells and a complete lack of response in the large cells.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:The feasibility and efficacy of treating patients with locally recurrent or metastatic non-small cell lung cancer (NSCLC) or head/neck cancer with interleukin-2 (IL-2), cisplatin, and 5-fluorouracil (5-FU) was tested. Treatment was given every 28 days and consisted of cisplatin, 100 mg/m2on days 1 and 8; 5-FU, 1,000 mg/m2by continuous infusion on days 1-3; and IL-2, 12 million units/m2 by i.v. bolus on days 15-19. Thirty-four patients (22 NSCLC, 12 head/neck cancer) were registered in the study. The median age was 58 years; 59% had Karnofsky performance status of 70-80% and over one-half received prior therapy. All patients were evaluable for toxicity and 29 (18 NSCLC, 11 head/neck cancer) were evaluable for response. Twenty-five patients experienced at least one grade 3 or 4 toxicity, but these toxicities were transient and, in general, well tolerated. The response rate was 37% for NSCLC (0 complete response, 7 partial response) and 55% for head/neck cancer (2 complete response, 4 partial response). Two patients with head/neck cancer responded to treatment after failing prior therapy with cisplatin/5-FU alone. The combination of IL-2, cisplatin, and 5-FU is tolerable and active for treatment of NSCLC and head/neck carcinoma; the combination may not be cross-resistant with other chemotherapy combinations. Further studies of IL-2 combined with cisplatin/5-FU are warranted to determine the most effective dose and schedule.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary: Interleukin-2 (IL-2) plus lymphokine-activated killer (LAK) cell therapy has antineoplastic activity in renal cancer and malignant melanoma. In order to explore the activity of this therapy in Hodgkin's disease and non- Hodgkin's lymphoma, the Extramural IL-2/LAK Working Group (ILWG) treated 27 patients on two protocols using high-dose IL-2 and autologous LAK cells. Two of 12 patients with Hodgkin's disease experienced partial responses lasting 6 and 12 weeks. No patient with non-Hodgkin's lymphoma responded (p=NS). The toxicities of therapy were similar to those reported by the ILWG from trials of IL-2/LAK in solid tumors, consisting of transient hemodynamic, cardiopulmonary, renal and hepatic dysfunction, skin rash, fever, and flu-like symptoms. In view of the low response rate and the brief duration of these responses, we do not recommend the regimens reported here for further investigation in Hodgkin's disease or non-Hodgkin's lymphomas

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Summary:Minor and reversible gastrointestinal side effects are common when patients receive interleukin-2 (IL-2) with or without lymphokine-activated killer (LAK) cells. We treated 42 cancer patients with IL-2 therapy and 3 patients developed serious gastrointestinal problems during treatment. Complications included sigmoid colon perforation, ischemic necrosis of the small and large intestine, and diffuse bowel ulceration. These were not associated with tumor implants or hypotension. Two patients died as a direct result of these problems despite aggressive surgical and medical management. The incidence of major gastrointestinal complications with IL-2 therapy may be greater than previously reported and a heightened awareness of potential gastrointestinal problems may circumvent considerable morbidity and mortality.

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID

ISSN:1524-9557    

出版商:OVID    

年代:1991

数据来源: OVID