Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
This article reviews the evidence for the danger model in the context of immune re­sponse to tumors and the insufficiency of the immune system to eliminate tumor growth. Despite their potential immunogenicity tumors do not induce significant immune re­sponses which could destroy malignant cells. According to the danger model, the im­mune surveillance system fails to detect tumor antigens because transformed cells do not send any danger signals which could activate dendritic cells and initiate an im­mune response. Instead, tumor cells or antigen presenting cells turn off the respond­ing T cells and induce tolerance. The studies reviewed herein based on model tumor antigens, recombinant viral vec­tors and detection of tumor specific T cells by MHC/peptide tetramers underscore the critical role of tumor antigen presentation and the context in which it occurs. They in­dicate that antigen presentation only by activated but not by cancer or resting den­dritic cells is necessary for the induction of immune responses to tumor antigens. It becomes apparent that the inability of dendritic cells to become activated provides a biological niche for tumor escape from immune destruction and seems to be a princi­pal mechanism for the failure of tumor immune surveillance.
EN
We have constructed and expressed recombinant chimeric soluble TGF-β type II receptor fused with the Fc portion of human IgG1 (sTβRII-Fc) in NS0 mouse myeloma cells and isolated cell lines constitutively secreting very high levels of biologically active protein. The GS-NS0 expression system takes advantage of the strong human cytomegalovirus immediate early promoter expression vector and glutamine synthetase as a selectable marker. The recombinant chimeric receptor could be produced in high amounts and efficiently purified by one step chromatography on a protein A column. Biochemical studies revealed that recombinant sTβRII-Fc binds native TGF-β1 and TGF-β3 isoforms and neutralizes their activity in vitro.
EN
The ability of various cytokines to hamper tumor growth or to induce anti-tumor im­mune response has resulted in their study as antitumor agents in gene therapy ap­proaches. In this review we will concentrate on the costimulation of antitumor immune re­sponses using modification of various cell types by cytokine genes. Several strategies have emerged such as (i) modification of tumor cells with cytokine genes ex vivo (whole tumor cell vaccines), (ii) ex vivo modification of other cell types for cytokine gene delivery, (iii) delivery of cytokine genes into tumor microenvironment in vivo, (iv) modification of dendritic cells with cytokine genes ex vivo. Originally single cytokine genes were used. Subsequently, multiple cytokine genes were applied simul­taneously, or in combination with other factors such as chemokines, membrane bound co-stimulatory molecules, or tumor associated antigens. In this review we dis­cuss these strategies and their use in cancer treatment as well as the promises and lim­itations of cytokine based cancer gene therapy. Clinical trials, including our own expe­rience, employing the above strategies are discussed.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.