Complexes of IL-2 and JES6-1 mAb (IL-2/JES6) provide strong sustained IL-2 signal selective for CD25+ cells and thus they potently expand Treg cells. IL-2/JES6 are effective in the treatment of autoimmune diseases and in protecting against rejection of pancreatic islet allografts. However, we found that IL-2/JES6 also dramatically increase sensitivity to LPS-mediated shock in C57BL/6 mice. We demonstrate here that this phenomenon is dependent on endogenous IFN-γ and T cells, as it is not manifested in IFN-γ deficient and nude mice, respectively. Administration of IL-2/JES6 leads to the emergence of CD25+Foxp3-CD4+ and CD25+Foxp3-CD8+ T cells producing IFN-γ in various organs, particularly in the liver. IL-2/JES6 also increase counts of CD11b+CD14+ cells in the blood and the spleen with higher sensitivity to LPS in terms of TNF-α production and induce expression of CD25 in these cells. These findings indicate safety issue for potential use of IL-2/JES6 or similar IL-2-like immunotherapeutics.
- MeSH
- interferon gama nedostatek MeSH
- interleukin-2 metabolismus MeSH
- lipopolysacharidy metabolismus MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši nahé MeSH
- myši MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Flow cytometry has revolutionized the field of molecular immunology, enabling the monitoring and characterization of immune events at the single-cell level. Here, we describe a flow cytometry-based workflow to quantify the activation of specific immune cell subsets in mice in response to a molecular intervention. Compared to laborious long-term disease models, this technique allows for relatively rapid evaluation of candidate therapeutics designed to elicit a targeted immune response. This approach has the range to address both disease applications in which an immunostimulatory effect would be desired (e.g., cancer, infectious disease) or those in which an immunosuppressive effect would be desired (e.g., autoimmune disorders, transplantation medicine). Overall, our technique presents a powerful and accessible strategy for preliminary in vivo assessment of potential immunotherapeutics.
- MeSH
- analýza jednotlivých buněk metody MeSH
- CD4-pozitivní T-lymfocyty transplantace MeSH
- CD8-pozitivní T-lymfocyty transplantace MeSH
- imunofenotypizace MeSH
- myši transgenní MeSH
- myši MeSH
- nádory imunologie terapie MeSH
- ovalbumin aplikace a dávkování imunologie MeSH
- převzatá imunita MeSH
- průběh práce MeSH
- průtoková cytometrie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Interleukin (IL)-2 has been approved for treatment of metastatic renal cancer and malignant melanoma. However, its unfavorable pharmacologic properties, severe side effects and the negative role of IL-2 in maintaining T regulatory cells are severe drawbacks. It has been shown that immunocomplexes of IL-2 and certain anti-IL-2 mAbs possess selective and high stimulatory activity in vivo. Here, we show that IL-2/S4B6 mAb immunocomplexes expand not only CD122(high) subsets and newly activated CD8(+) T cells but also natural killer T cells and γδ T cells. Further, we demonstrate that natural killer (NK) cells expanded by IL-2/S4B6 mAb immunocomplexes in vivo have high cytolytic activity, which can be further increased by coadministration of IL-12. We also demonstrate that IL-2/S4B6 mAb immunocomplexes possess noticeable antitumor activity in two syngeneic mouse tumor models, namely BCL1 leukemia and B16F10 melanoma, but only if administered early in tumor progression. To effectively treat established tumors, we administered the tumor-bearing mice first with N-(2-hydroxypropyl)methacrylamide copolymer-bound doxorubicin conjugate, and subsequently with IL-2/S4B6 mAb immunocomplexes alone or with IL-12 to induce an efficient antitumor immune response. Importantly, we show that the conjugate has significantly lower immunosuppressive activity than free doxorubicin when using dosage with comparable antitumor activity, thus eliminating the majority of tumor cells while leaving the immune system mostly unimpaired for stimulation with IL-2/S4B6 mAb immunocomplexes. Indeed, we demonstrate that the conjugate and IL-2/S4B6 mAb immunocomplexes together have synergistic antitumor activity.
- MeSH
- akrylamidy aplikace a dávkování MeSH
- buňky NK imunologie MeSH
- CD8-pozitivní T-lymfocyty imunologie MeSH
- doxorubicin aplikace a dávkování MeSH
- experimentální leukemie terapie MeSH
- imunokonjugáty terapeutické užití MeSH
- imunosupresiva aplikace a dávkování MeSH
- interleukin-12 aplikace a dávkování MeSH
- interleukin-2 imunologie terapeutické užití MeSH
- melanom experimentální terapie MeSH
- monoklonální protilátky aplikace a dávkování MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
IL-2 is potent imunostimulatory molecule that plays a key role in T and NK cell activation and expansion. IL-2 is approved by the FDA to treat metastatic renal cancer and melanoma, but its extremely short half-life and serious toxicities are significant limitations of its use. It was reported that in vivo biological activity of IL-2 can be increased by association of IL-2 with anti-IL-2 mAb (S4B6). IL-2/S4B6 mAb immunocomplexes were described to be highly stimulatory for NK and memory CD8(+) T cells and intermediately also for regulatory T cells. IL-2/JES6-1 mAb immunocomplexes are stimulatory solely for regulatory T cells. In this study we show that although both mentioned IL-2 immunocomplexes are less potent than free IL-2 in vitro, they possess extremely high stimulatory activity to expand activated naive CD8(+) T cells in vivo. IL-2 immunocomplexes expand activated naive CD8(+) T cells several hundred-fold times after four doses and more than 1000-fold times after six doses (1.5 microg/dose of IL-2), whereas free IL-2 given at the same dosage shows negligible activity. IL-2/S4B6 mAb immunocomplexes also induce massive expansion of NK cells (40% of DX5(+)NK1.1(+) cells in spleen). Importantly, activated naive CD8(+) T cells expanded by IL-2 immunocomplexes form robust population of functional memory cells. We also demonstrate in two distinct tumor models that IL-2/S4B6 mAb immunocomplexes possess considerable antitumor activity. Finally, by using radioactively labeled IL-2, we provide for first time direct evidence that IL-2 immunocomplexes have much longer half-life in circulation than free IL-2, being approximately 3 h vs <15 min, respectively.
- MeSH
- buňky NK imunologie MeSH
- CD8-pozitivní T-lymfocyty imunologie MeSH
- imunokomplex terapeutické užití MeSH
- imunoterapie MeSH
- interleukin-2 terapeutické užití MeSH
- monoklonální protilátky terapeutické užití MeSH
- myši inbrední BALB C MeSH
- myši inbrední C57BL MeSH
- myši transgenní MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory imunologie terapie MeSH
- poločas MeSH
- převzatá imunita MeSH
- rekombinantní proteiny farmakologie MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- práce podpořená grantem MeSH
