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1.
Díaz-Montero CM El Naggar S Al Khami A El Naggar R Montero AJ Cole DJ Salem ML 《Cancer immunology, immunotherapy : CII》2008,57(4):563-572
During the antigen-dependant activation process several subsets CD8+ T cells appear with different phenotypic and functional characteristics. Recent studies indicate that the state of T cell differentiation radically affects their ability to effectively respond to tumor challenge, with early effector CD8+ T (CD62Lhigh) cells having better anti-tumor activity. Thus strategies aimed at optimizing the generation of such subpopulations could significantly enhance the effectiveness of adoptive cell therapy (ACT) for cancer. In this study, we show that priming of naïve CD8+ T cells in the presence of IL-12 selectively rescued early CD8+ CD62Lhi from activation induced cell death and resulted in the increased accumulation of this subset of CD8+ T cells. Furthermore, we demonstrated that IL-12 directly modulated the expression of CD62L on activated CD8+ T cells. When used for ACT, naïve CD8+ T cells primed in vitro in the presence of IL-12 showed superior anti-tumor activity toward B16 melanoma. Importantly, using the Pmel-1 model, priming pmel-1 cells in vitro with IL-12 reduced the state of functional tolerance associated with the non-mutated “self” tumor antigen gp100, as demonstrated by significant tumor responses in the absence of vaccination. Together, our results suggest that in vitro conditioning of naïve CD8+ T cells with IL-12 prior to ACT could significantly enhance their anti-tumor activity. 相似文献
2.
Søndergaard H Frederiksen KS Thygesen P Galsgaard ED Skak K Kristjansen PE Odum N Kragh M 《Cancer immunology, immunotherapy : CII》2007,56(9):1417-1428
Interleukin (IL)-21 is a recently discovered cytokine in early clinical development, which has shown anti-tumor activity in
various animal models. In the present study, we examine the anti-tumor activity of IL-21 protein therapy in two syngeneic
tumor models and its effect on the density of tumor infiltrating T cells. We treated mice bearing established subcutaneous
B16 melanomas or RenCa renal cell carcinomas with intraperitoneal (i.p.) or subcutaneous (s.c.) IL-21 protein therapy and
subsequently scored the densities of tumor infiltrating CD4+ and CD8+ T cells by immunohistochemistry. Whereas both routes of IL-21 administration significantly inhibited growth of small, established
RenCa and B16 tumors, only s.c. therapy significantly inhibited the growth of large, established tumors. We found a greater
bioavailability and significant drainage of IL-21 to regional lymph nodes following s.c. administration, which could account
for the apparent increase in anti-tumor activity. Specific depletion of CD8+ T cells with monoclonal antibodies completely abrogated the anti-tumor activity, whereas NK1.1+ cell depletion did not affect tumor growth. In accordance, both routes of IL-21 administration significantly increased the
density of tumor infiltrating CD8+ T cells in both B16 and RenCa tumors; and in the RenCa model s.c. administration of IL-21 led to a significantly higher density
of tumor infiltrating CD8+ T cells compared to i.p. administration. The densities of CD4+ T cells were unchanged following IL-21 treatments. Taken together, these data demonstrate that IL-21 protein has anti-tumor
activity in established syngeneic tumors, and we show that IL-21 therapy markedly increases the density of tumor infiltrating
CD8+ T cells. 相似文献
3.
Huck SP Tang SC Andrew KA Yang J Harper JL Ronchese F 《Cancer immunology, immunotherapy : CII》2008,57(1):63-71
Aims
To examine the effects of route of administration and activation status on the ability of dendritic cells (DC) to accumulate in secondary lymphoid organs, and induce expansion of CD8+ T cells and anti-tumor activity.Methods
DC from bone marrow (BM) cultures were labeled with fluorochromes and injected s.c. or i.v. into naïve mice to monitor their survival and accumulation in vivo. Percentages of specific CD8+ T cells in blood and delayed tumor growth were used as readouts of the immune response induced by DC immunization.Results
The route of DC administration was critical in determining the site of DC accumulation and time of DC persistence in vivo. DC injected s.c. accumulated in the draining lymph node, and DC injected i.v. in the spleen. DC appeared in the lymph node by 24 h after s.c. injection, their numbers peaked at 48 h and declined at 96 h. DC that had spontaneously matured in vitro were better able to migrate compared to immature DC. DC were found in the spleen at 3 h and 24 h after i.v. injection, but their numbers were low and declined by 48 h. Depending on the tumor cell line used, DC injected s.c. were as effective or more effective than DC injected i.v. at inducing anti-tumor responses. Pre-treatment with LPS increased DC accumulation in lymph nodes, but had no detectable effect on accumulation in the spleen. Pre-treatment with LPS also improved the ability of DC to induce CD8+ T cell expansion and anti-tumor responses, regardless of the route of DC administration.Conclusions
Injection route and activation by LPS independently determine the ability of DC to activate tumor-specific CD8+ T cells in vivo.4.
Bettahi I Dasgupta G Renaudet O Chentoufi AA Zhang X Carpenter D Yoon S Dumy P BenMohamed L 《Cancer immunology, immunotherapy : CII》2009,58(2):187-200
Molecularly defined synthetic vaccines capable of inducing both antibodies and cellular anti-tumor immune responses, in a
manner compatible with human delivery, are limited. Few molecules achieve this target without utilizing external immuno-adjuvants.
In this study, we explored a self-adjuvanting glyco-lipopeptide (GLP) as a platform for cancer vaccines using as a model MO5,
an OVA-expressing mouse B16 melanoma. A prototype B and T cell epitope-based GLP molecule was constructed by synthesizing
a chimeric peptide made of a CD8+ T cell epitope, from ovalbumin (OVA257–264) and an universal CD4+ T helper (Th) epitope (PADRE). The resulting CTL–Th peptide backbones was coupled to a carbohydrate B cell epitope based
on a regioselectively addressable functionalized templates (RAFT), made of four α-GalNAc molecules at C-terminal. The N terminus
of the resulting glycopeptides (GP) was then linked to a palmitic acid moiety (PAM), obviating the need for potentially toxic
external immuno-adjuvants. The final prototype OVA-GLP molecule, delivered in adjuvant-free PBS, in mice induced: (1) robust
RAFT-specific IgG/IgM that recognized tumor cell lines; (2) local and systemic OVA257–264-specific IFN-γ producing CD8+ T cells; (3) PADRE-specific CD4+ T cells; (4) OVA-GLP vaccination elicited a reduction of tumor size in mice inoculated with syngeneic murine MO5 carcinoma
cells and a protection from lethal carcinoma cell challenge; (5) finally, OVA-GLP immunization significantly inhibited the
growth of pre-established MO5 tumors. Our results suggest self-adjuvanting glyco-lipopeptide molecules as a platform for B
Cell, CD4+, and CD8+ T cell epitopes-based immunotherapeutic cancer vaccines.
Both I. Bettahi and G. Dasgupta have contributed equally to this work. 相似文献
5.
Elkord E Burt DJ Drijfhout JW Hawkins RE Stern PL 《Cancer immunology, immunotherapy : CII》2008,57(6):833-847
Background The human 5T4 (h5T4) oncofoetal antigen is expressed by a wide variety of human carcinomas including colorectal, ovarian,
gastric and renal, but rarely on normal tissues. Its restricted expression on tumour tissues as well as its association with
tumour progression and bad prognosis has driven the development of a MVA-based vaccine (TroVax) which has been tested in several
early phase clinical trials and these studies have led to the start of a phase III trial in renal cell carcinoma patients.
We have recently shown that CD8+ T cells recognizing h5T4 can be generated in the absence of CD4+ T cells from peripheral blood lymphocytes of human healthy individuals.
Results We report the existence and expansion of human CD4+ T cells against h5T4 by stimulation with autologous monocyte-derived dendritic cells infected with a replication defective
adenovirus encoding the h5T4 cDNA (Ad-h5T4). The h5T4-specific T-cell responses in normal individuals are enhanced by initial
depletion of CD25+ cells (putative T regulatory cells) prior to the in vitro stimulation. We have identified a novel h5T4-derived 15-mer peptide
recognized by CD4+ T cells in HLA-DR4 positive healthy individuals. Interestingly, CD4+ T cells spontaneously recognizing a different 5T4 epitope restricted by HLA-DR were identified in tumour-infiltrating lymphocytes
isolated from a regressing renal cell carcinoma lung metastasis.
Conclusion Our data show that CD4+ T cells recognizing h5T4 can be expanded and detected in healthy individuals and a renal cell carcinoma patient. Such h5T4-specific
CD4+ T cells boosted or induced by vaccination could act to modulate both cell or antibody mediated anti-tumour responses.
This work was supported by Cancer Research UK. 相似文献
6.
Cristina Maccalli Samantha Scaramuzza Giorgio Parmiani 《Cancer immunology, immunotherapy : CII》2009,58(5):801-808
Innate and adaptive immune responses have many interactions that are regulated by the balance of signals initiated by a variety
of activatory and inhibitory receptors. Among these, the NKG2D molecule was identified as expressed by T lymphocytes, including
most CD8+ cells and a minority of CD4+ cells, designated TNK cells in this paper. Tumor cells may overexpress the stress-inducible NKG2D ligands (NKG2DLs: MICA/B,
ULBPs) and the NKG2D signaling has been shown to be involved in lymphocyte-mediated anti-tumor activity. Aberrant expression
of NKG2DLs by cancer cells, such as the release of soluble form of NKG2DLs, can lead to the impairment of these immune responses.
Here, we discuss the significance of NKG2D in TNK-mediated anti-tumor activity. Our studies demonstrate that NKG2D+ T cells (TNK) are commonly recruited at the tumor site in melanoma patients where they may exert anti-tumor activity by engaging
both TCR and NKG2D. Moreover, NKG2D and TCR triggering was also observed by peripheral blood derived T lymphocyte- or T cell
clone-mediated tumor recognition, both in melanoma and colorectal cancer (CRC) patients. Notably, heterogeneous expression
of NKG2DLs was found in melanoma and CRC cells, with a decrease of these molecules along with tumor progression. Therefore,
through the mechanisms that govern NKG2D engagement in anti-tumor activity and the expression of NKG2DLs by tumor cells that
still need to be dissected, we showed that NKG2D expressing TNK cells are a relevant T cell subtype for immunosurveillance
of tumors and we propose that new immunotherapeutic interventions for cancer patients should be aimed also at enhancing NKG2DLs
expression by tumor cells.
This paper is a focused research review based on a presentation given at the sixth annual meeting of the Association for Immunotherapy
of Cancer (CIMT), held in Mainz, Germany, 15–16 May 2008. 相似文献
7.
8.
We have previously demonstrated that multiple immunizations with vector-based vaccines containing transgenes for tumor Ags
and a triad of costimulatory molecules (TRICOM) enhance the expansion and functional avidity of Ag-specific memory CD8+ T cells in a mouse model. However, the effect of enhanced costimulation on human memory CD8+ T cells is still unclear. The study reported here was an in vitro investigation of the proliferation and function of CEA-specific
human memory CD8+ T cells following enhanced costimulation. Our results demonstrated that TRICOM costimulation enhanced production of multiple
cytokines and expansion of CEA-specific memory CD8+ T cells. The lytic capacity of memory CTLs toward CEA+ tumors was also significantly enhanced. IL-2Rα (CD25) was upregulated dramatically following APC-TRICOM stimulation, suggesting
that the enhanced expansion of memory CD8+ T cells may be mediated by increased expression of IL-2R on memory T cells. The enhanced cytokine production and proliferation
following TRICOM signaling was completely blocked by the combination of neutralizing Abs against B7-1, ICAM-1, and LFA-3,
the costimulatory molecules comprising TRICOM. No difference in T-cell apoptosis was observed between APC-TRICOM and APC-wild-type
groups, as determined by annexin V, Bcl-2, and active caspase-3 staining. Results indicated that enhanced costimulation greatly
expanded human CEA-specific CD8+ T cells and enhanced T-cell function, without inducing increased apoptosis of CEA-specific memory CD8+ T cells. 相似文献
9.
Iero M Squarcina P Romero P Guillaume P Scarselli E Cerino R Carrabba M Toutirais O Parmiani G Rivoltini L 《Cancer immunology, immunotherapy : CII》2007,56(12):1979-1991
The use of “altered peptide ligands” (APL), epitopes designed for exerting increased immunogenicity as compared with native
determinants, represents nowadays one of the most utilized strategies for overcoming immune tolerance to self-antigens and
boosting anti-tumor T cell-mediated immune responses. However, the actual ability of APL-primed T cells to cross-recognize
natural epitopes expressed by tumor cells remains a crucial concern. In the present study, we show that CAP1-6D, a superagonist
analogue of a carcinoembriyonic antigen (CEA)-derived HLA-A*0201-restricted epitope widely used in clinical setting, reproducibly
promotes the generation of low-affinity CD8+ T cells lacking the ability to recognized CEA-expressing colorectal carcinoma (CRC) cells. Short-term T cell cultures, obtained
by priming peripheral blood mononuclear cells from HLA-A*0201+ healthy donors or CRC patients with CAP1-6D, were indeed found to heterogeneously cross-react with saturating concentrations
of the native peptide CAP1, but to fail constantly lysing or recognizing through IFN- γ release CEA+CRC cells. Characterization of anti-CAP1-6D T cell avidity, gained through peptide titration, CD8-dependency assay, and staining
with mutated tetramers (D227K/T228A), revealed that anti-CAP1-6D T cells exerted a differential interaction with the two CEA
epitopes, i.e., displaying high affinity/CD8-independency toward the APL and low affinity/CD8-dependency toward the native
CAP1 peptide. Our data demonstrate that the efficient detection of self-antigen expressed by tumors could be a feature of
high avidity CD8-independent T cells, and underline the need for extensive analysis of tumor cross-recognition prior to any
clinical usage of APL as anti-cancer vaccines. 相似文献
10.
Lundin KU Screpanti V Omholt H Hofgaard PO Yagita H Grandien A Bogen B 《Cancer immunology, immunotherapy : CII》2004,53(12):1135-1145
B-lymphoma cells express a highly tumor-specific antigen, monoclonal Ig, which is a promising target for immunotherapy. Previous work has demonstrated that B-lymphoma cells spontaneously process their endogenous monoclonal Ig and present variable (V) region peptides (Id-peptides) on their MHC class II molecules to CD4+ T cells. Id-specific CD4+ T cells protect mice against B-lymphoma cells in the absence of anti-idiotypic antibodies. The molecular mechanism by which Id-specific CD4+ T cells kill B-lymphoma cells is hitherto unknown. We here demonstrate in an Id-specific T-cell receptor (TCR)–transgenic mouse model that Id-specific CD4+ T cells induce apoptosis of Fas+ B-lymphoma cells in vitro by FasLigand (FasL)–Fas interaction. Moreover, the rare B lymphomas that had escaped rejection in TCR-transgenic mice had down-regulated their sensitivity to Fas-mediated apoptosis. Although these results suggest that FasL-Fas interaction is important, Id-specific CD4+ T cells could eliminate Id+ B-lymphoma cells in vivo by other mechanisms, since three independent ways of blocking FasL-Fas–mediated killing failed to abrogate tumor protection in TCR-transgenic mice. These results suggest that there are several redundant pathways by which Id-specific CD4+ T cells eliminate Id+ B-lymphoma cells in vivo, of which FasL-Fas interaction is only one.Supported by grants from the Norwegian Cancer Society, the Research Council of Norway, and the Multiple Myeloma Research Foundation. 相似文献
11.
Petrovas C Mueller YM Yang G Altork SR Jacobson JM Pitsakis PG Mounzer KC Altman JD Katsikis PD 《Apoptosis : an international journal on programmed cell death》2007,12(12):2175-2186
We have recently provided data suggesting a potential role for mitochondria and Bcl-2-family molecules in apoptosis sensitivity
of HIV-specific CD8+ T cells. Here, we report on the role of filamentous (F) actin in this process. Disruption of actin by cytochalasin D (cytD)
or lantrunculin A remarkably reduced CD95/Fas-induced apoptosis of HIV-specific CD8+ T cells while their spontaneous apoptosis was unaffected. This inhibition cannot be attributed to changes of CD95/Fas distribution
or levels in these cells. Furthermore, cytD treatment reduced CD95/Fas-induced apoptosis of CD8+ T cells from HIV+ patients independently of their differentiation status. CD95/Fas-induced apoptosis of both CD38+ and CD38− HIV-specific CD8+ T cells was inhibited by cytD treatment indicating that actin mediates this apoptotic process independently of the activation
level of these cells. CytD was found to reduce the activation of caspase-8 induced by short treatment of purified CD8+ T cells from HIV+ patients with anti-CD95/Fas. Our data reveal actin as a critical mediator of HIV-specific CD8+ T cell apoptosis; further analysis of the molecular mechanisms governing this process may potentially contribute to design
new therapies targeting the enhancement of the immune system in HIV infection. 相似文献
12.
Three mouse killer immunoglobulin-like receptors (KIRs), namely, KIR3DL1, KIRL1, and KIRL2, have recently been identified
in C56BL/6 (B6) mice. However, only two Kir genes are found in the B6 mouse genome sequence data base. To clarify this discrepancy, we cloned Kir cDNAs from multiple strains of mice. Sequencing of the cDNA clones showed that the Kir3dl1 gene is found in C3H/HeJ and CBA/J but not in B6 mice. Analysis of the single nucleotide polymorphism data base suggested
that Kir3dl1 is the C3H/HeJ and CBA/J allele of Kirl1. We generated mAb to the recombinant KIRL1 protein to investigate its expression pattern. The anti-KIRL1 mAb bound to NK1.1+ T cells but only very weakly or at undetectable levels to other lymphocytes including natural killer (NK) cells and conventional
T cells. Among NK1.1+ T cells, conventional NK T cells stained with CD1d tetramer did not significantly bind anti-KIRL1 mAb, whereas CD1d-tetramer-negative
subset was KIRL1-positive. Furthermore, the expression of KIRL1 is readily detected on NK1.1+ T cells from β2-microglobulin-deficient B6 mice. Thus, KIRL1 is predominantly expressed on CD1d-independent NK1.1+ T cells. 相似文献
13.
14.
Targeting interleukin-2 (IL-2) and/or agonist anti-CD40 antibody (Ab) into tumors represents an effective vaccination strategy
that avoids systemic toxicity and resolves treated-site tumors. Here, we examined IL-2 and/or anti-CD40 Ab-driven local versus
systemic T cell function and the installation of T cell memory. Single tumor studies showed that IL-2 induced a potent CD4+ and CD8+ T cell response that was limited to the draining lymph node and treated-site tumor, and lymph node tumor-specific CD8+ T cells did not upregulate CD44. A two-tumor model showed that while IL-2-treated-site tumors resolved, distal tumors continued
to grow, implying limited systemic immunity. In contrast, anti-CD40 Ab treatment with or without IL-2 expanded the systemic
T cell response to non-draining lymph nodes, and distal tumors resolved. Tumor-specific T cells in lymph nodes of anti-CD40
Ab ± IL-2-treated mice upregulated CD44, demonstrating activation and transition to effector/memory migratory cells. While
CD40-activated CD4+ T cells were not required for eradicating treated-site tumors, they, plus CD8+ T cells, were crucial for removing distal tumors. Rechallenge/depletion experiments showed that the effector/memory phase
required the presence of previously CD40/IL-2-activated CD4+ and CD8+ T cells to prevent recurrence. These novel findings show that different T cell effector mechanisms can operate for the eradication
of local treated-site tumors versus untreated distal tumors and that signaling through CD40 generates a whole of body, effector/memory
CD4+ and CD8+ T cell response that is amplified and prolonged via IL-2. Thus, successful immunotherapy needs to generate collaborating
CD4+ and CD8+ T cells for a complete long-term protective cure. 相似文献
15.
Craig Gedye Juliet Quirk Judy Browning Suzanne Svobodová Thomas John Pavel Sluka P. Rod Dunbar Denis Corbeil Jonathan Cebon Ian D. Davis 《Cancer immunology, immunotherapy : CII》2009,58(10):1635-1646
“Cancer stem cells” that resist conventional treatments may be a cause of therapeutic failure in melanoma. We report a subpopulation
of clonogenic melanoma cells that are characterized by high prominin-1/CD133 expression in melanoma and melanoma cell lines.
These cells have enhanced clonogenicity and self-renewal in vitro, and serve as a limited in vitro model for melanoma stem
cells. In some cases clonogenic CD133+ melanoma cells show increased expression of some cancer/testis (CT) antigens. The expression of NY-ESO-1 in an HLA-A2 expressing
cell line allowed CD133+ clonogenic melanoma cells to be targeted for killing in vitro by NY-ESO-1-specific CD8+ T-lymphocytes. Our in vitro findings raise the hypothesis that if melanoma stem cells express CT antigens in vivo that immune
targeting of these antigens may be a viable clinical strategy for the adjuvant treatment of melanoma.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
16.
The healthy colorectal mucosa contains many resident intraepithelial lymphocytes (IELs) consisting of partially activated
yet hyporesponsive CD8+ T cells. A predominant feature of colorectal cancers (CRCs) characterized by high levels of microsatellite instability (MSI-H)
is heavy infiltration by an intraepithelial population of tumor infiltrating lymphocytes (iTILs). While it has been assumed
that these iTILs originate from tumor infiltration by peripheral CD8+ effector T cells, their origin remains unknown. In light of the phenotypic and functional differences exhibited by IELs and
peripheral T cells, elucidation of the precursor population of iTILs in MSI-H CRCs could clarify the role played by these
lymphocytes in tumor progression. The aim of the present study was to investigate whether MSI-H CRCs interact differently
with IEL- versus peripherally-derived CD8+ T cells. Using a Transwell assay system to mimic basolateral infiltration of tumor cells by lymphocytes, T cell migration,
retention, proliferation and phenotypic alterations were investigated. Results indicate that MSI-H CRCs preferentially retain
and expand IEL-derived cells to a greater degree than their microsatellite stable (MSS) counterparts. While MSI-H CRCs also
retained more peripherally derived T cells, this number was considerably less than that from the IEL population. While interaction
of IELs with either CRC type led to baseline lymphocyte activation, MSS CRCs induced upregulation of additional activation
markers on retained IELs compared to MSI-H CRCs. These results suggest that the abundant iTILs present in MSI-H CRCs result
from expansion of the preexisting mucosal IEL population and imply a limited prognostic role for iTILs in MSI-H CRC. 相似文献
17.
Resting naive CD4+CD45R0?CD45RA+ T cells are sensitive to ionomycin. In contrast, resting CD4+CD45RA?CD45R0+ memory T cells show resistance to this Ca2+ ionophore. In the present study, the ability of activated T lymphocytes to respond to ionomycin during the transition from naive precursors into memory T cells has been analyzed. Activated CD4+CD45RA+CD45R0+ T cells are always present both in human peripheral blood (HPB) and in the ionomycin-resistant (IR) fraction. Therefore, some activated T cells are resistant toward the Ca2+ ionophore. CD69 molecules are markers of the very early stage of T cell activation. However, CD4+CD69+ T cells have never been found in the IR fraction. Thus, the majority of CD4+ T lymphocytes at the early stage of activation are ionomycin-sensitive cells. The proportion of CD4+CD25+ T cells did not differ significantly in HPB and in the IR fraction. The presence of CD4+CD25+ T lymphocytes in the IR fraction reflects changes in the Ca2+-signaling pathway at this differentiation step of activated cells. Depending on the expression level of CD25 molecules, the population of CD4+CD25+ cells is divided in T-regulatory (CD25high) and proliferating (CD25low) subpopulations. The action of ionomycin results in a decrease in the portion of the CD4+CD25low T-cells, but it leads to an increase in the proportion of the CD4+CD25high T lymphocytes. Consequently, greater portion of CD4+CD25high T lymphocytes and smaller portion of CD4+CD25low T cells are IR cells. Expression of HLA-DR molecules can be used as the marker for the late activation step. The IR fraction is significantly rich in CD4+HLA-DR+ T lymphocytes in comparison to the blood of the same donor. The link between different differentiation steps of CD4+ T-lymphocytes and alterations in calcium ion homeostasis is discussed. 相似文献
18.
19.
Albrecht J Frey M Teschner D Carbol A Theobald M Herr W Distler E 《Cancer immunology, immunotherapy : CII》2011,60(2):235-248
Clinical tumor remissions after adoptive T-cell therapy are frequently not durable due to limited survival and homing of transfused
tumor-reactive T cells, what can be mainly attributed to the long-term culture necessary for in vitro expansion. Here, we
introduce an approach allowing the reliable in vitro generation of leukemia-reactive cytotoxic T lymphocytes (CTLs) from naive
CD8+ T cells of healthy donors, leading to high cell numbers within a relatively short culture period. The protocol includes the
stimulation of purified CD45RA+ CD8+ T cells with primary acute myeloid leukemia blasts of patient origin in HLA-class I-matched allogeneic mixed lymphocyte-leukemia
cultures. The procedure allowed the isolation of a large diversity of HLA-A/-B/-C-restricted leukemia-reactive CTL clones
and oligoclonal lines. CTLs showed reactivity to either leukemia blasts exclusively, or to leukemia blasts as well as patient-derived
B lymphoblastoid-cell lines (LCLs). In contrast, LCLs of donor origin were not lysed. This reactivity pattern suggested that
CTLs recognized leukemia-associated antigens or hematopoietic minor histocompatibility antigens. Consistent with this hypothesis,
most CTLs did not react with patient-derived fibroblasts. The efficiency of the protocol could be further increased by addition
of interleukin-21 during primary in vitro stimulation. Most importantly, leukemia-reactive CTLs retained the expression of
early T-cell differentiation markers CD27, CD28, CD62L and CD127 for several weeks during culture. The effective in vitro
expansion of leukemia-reactive CD8+ CTLs from naive CD45RA+ precursors of healthy donors can accelerate the molecular definition of candidate leukemia antigens and might be of potential
use for the development of adoptive CTL therapy in leukemia. 相似文献
20.
Maria Giovanna di Bari M. E. Christine Lutsiak Shinji Takai Sven Mostböck Benedetto Farsaci Roshanak Tolouei Semnani Lalage M. Wakefield Jeffrey Schlom Helen Sabzevari 《Cancer immunology, immunotherapy : CII》2009,58(11):1809-1818
This study demonstrates that CD8+ T cells in the tumor microenvironment display reduced functionality and hyporesponsiveness. TGF-β contributed markedly to
the tumor-infiltrating CD8+ T cells’ (TILs) reduced functionality, which could be reversed using a small molecule TGF-β inhibitor. Upon T-cell receptor
(TCR) activation, the activation of ITK and ERK kinases were reduced in CD8+ TILs, as compared to splenic CD8+ T cells: TGF-β inhibitor could reverse this phenomenon. This study demonstrates for the first time the association of the
Spred-1 gene, an inhibitor of the Ras/MAPK pathway, with CD8+ TILs and TGF-β activity. Spred-1 was upregulated in CD8+ TILs and TGF-β enhanced the expression of Spred-1 in effector/memory CD8+ T cells and not in rested/memory CD8+ T cells. Based on these findings, this study supports the hypothesis that TGF-β mediates an inhibitory mechanism on CD8+ TILs involving TCR-signaling blockade and the upregulation of Spred-1, thus implicating Spred-1 as a potential new target
for future anti-tumor immune studies.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
M. G. di Bari and M. E. C. Lutsiak contributed equally to this work. 相似文献