scholarly journals Antitumor Reactive T-Cell Responses Are Enhanced In Vivo by DAMP Prothymosin Alpha and Its C-Terminal Decapeptide

Cancers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1764 ◽  
Author(s):  
Anastasios I. Birmpilis ◽  
Chrysoula-Evangelia Karachaliou ◽  
Pinelopi Samara ◽  
Kyriaki Ioannou ◽  
Platon Selemenakis ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Tumor Antigens ◽  
Ex Vivo ◽  
Peptide Vaccine ◽  
Mouse Serum ◽  
Prothymosin Α ◽  
Cell Functions

Prothymosin α (proTα) and its C-terminal decapeptide proTα(100–109) were shown to pleiotropically enhance innate and adaptive immune responses. Their activities have been broadly studied in vitro, focusing primarily on the restoration of the deficient immunoreactivity of cancer patients’ leukocytes. Previously, we showed that proTα and proTα(100–109) act as danger-associated molecular patterns (DAMPs), ligate Toll-like receptor-4, signal through TRIF- and MyD88-dependent pathways, promote the maturation of dendritic cells and elicit T-helper type 1 (Th1) immune responses in vitro, leading to the optimal priming of tumor antigen-reactive T-cell functions. Herein, we assessed their activity in a preclinical melanoma model. Immunocompetent mice bearing B16.F1 tumors were treated with two cycles of proTα or proTα(100–109) together with a B16.F1-derived peptide vaccine. Coadministration of proTα or proTα(100–109) and the peptide vaccine suppressed melanoma-cell proliferation, as evidenced by reduced tumor-growth rates. Higher melanoma infiltration by CD3+ T cells was observed, whereas ex vivo analysis of mouse total spleen cells verified the in vivo induction of melanoma-reactive cytotoxic responses. Additionally, increased levels of proinflammatory and Th1-type cytokines were detected in mouse serum. We propose that, in the presence of tumor antigens, DAMPs proTα and proTα(100–109) induce Th1-biased immune responses in vivo. Their adjuvant ability to orchestrate antitumor immunoreactivities can eventually be exploited therapeutically in humans.

scholarly journals Neem Leaf Glycoprotein Partially Rectifies Suppressed Dendritic Cell Functions and Associated T Cell Efficacy in Patients with Stage IIIB Cervical Cancer

2011 ◽  
Vol 18 (4) ◽  
pp. 571-579 ◽  
Author(s):  
Soumyabrata Roy ◽  
Shyamal Goswami ◽  
Anamika Bose ◽  
Krishnendu Chakraborty ◽  
Smarajit Pal ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Dendritic Cells ◽  
T Cell ◽  
Ex Vivo ◽  
Stage Iiib ◽  
Immune Functions ◽  
Cell Functions

ABSTRACTMyeloid-derived dendritic cells (DCs) generated from monocytes obtained from stage IIIB cervical cancer (CaCx IIIB) patients show dysfunctional maturation; thus, antitumor T cell functions are dysregulated. In an objective to optimize these dysregulated immune functions, the present study is focused on the ability of neem leaf glycoprotein (NLGP), a nontoxic preparation of the neem leaf, to induce optimum maturation of dendritic cells from CaCx IIIB patients.In vitroNLGP treatment of immature DCs (iDCs) obtained from CaCx IIIB patients results in upregulated expression of various cell surface markers (CD40, CD83, CD80, CD86, and HLA-ABC), which indicates DC maturation. Consequently, NLGP-matured DCs displayed balanced cytokine secretions, with type 1 bias and noteworthy functional properties. These DCs displayed substantial T cell allostimulatory capacity and promoted the generation of cytotoxic T lymphocytes (CTLs). Although NLGP-matured DCs derived from CaCx monocytes are generally subdued compared to those with a healthy monocyte origin, considerable revival of the suppressed DC-based immune functions is notedin vitroat a fairly advanced stage of CaCx, and thus, further exploration ofex vivoandin vivoDC-based vaccines is proposed. Moreover, the DC maturating efficacy of NLGP might be much more effective in the earlier stages of CaCx, where the extent of immune dysregulation is less and, thus, the scope of further investigation may be explored.

scholarly journals Blood DCs activated with R848 and poly(I:C) induce antigen-specific immune responses against viral and tumor-associated antigens

2021 ◽  
Author(s):  
Gerulf Hänel ◽  
Caroline Angerer ◽  
Katja Petry ◽  
Felix S. Lichtenegger ◽  
Marion Subklewe
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Cell Activation ◽  
Nk Cell ◽  
Ex Vivo ◽  
Poly I:C ◽  
Tumor Associated Antigens ◽  
Cell Induction

AbstractMonocyte-derived Dendritic cells (DCs) have successfully been employed to induce immune responses against tumor-associated antigens in patients with various cancer entities. However, objective clinical responses have only been achieved in a minority of patients. Additionally, generation of GMP-compliant DCs requires time- and labor-intensive cell differentiation. In contrast, Blood DCs (BDCs) require only minimal ex vivo handling, as differentiation occurs in vivo resulting in potentially better functional capacities and survival. We aimed to identify a protocol for optimal in vitro activation of BDCs including the three subsets pDCs, cDC1s, and cDC2s. We evaluated several TLR ligand combinations and demonstrated that polyinosinic:polycytidylic acid [poly(I:C)] and R848, ligands for TLR3 and TLR7/8, respectively, constituted the optimal combination for inducing a positive co-stimulatory profile in all BDC subsets. In addition, TLR3 and TLR7/8 activation led to high secretion of IFN-α and IL-12p70. Simultaneous as opposed to separate tailored activation of pDCs and cDCs increased immunostimulatory capacities, suggesting that BDC subsets engage in synergistic cross-talk during activation. Stimulation of BDCs with this protocol resulted in enhanced migration, high NK-cell activation, and potent antigen-specific T-cell induction.We conclude that simultaneous activation of all BDC subsets with a combination of R848 + poly(I:C) generates highly immunostimulatory DCs. These results support further investigation and clinical testing, as standalone or in conjunction with other immunotherapeutic strategies including adoptive T-cell transfer and checkpoint inhibition.

The in vivo targeting of tumor antigens to DCs by administration of transduced autologous lymphocytes results in robust and prolonged immunization: Pre-clinical validation and results of a pilot clinical studies of vaccination for metastatic melanoma

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 2525-2525 ◽  
Author(s):  
V. Russo ◽  
A. Cipponi ◽  
R. Fontana ◽  
D. Maggioni ◽  
F. Ciceri ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Tumor Antigens ◽  
Ex Vivo ◽  
Genetically Modified ◽  
Long Term Memory ◽  
Tumor Bearing ◽  
Presentation Pathway

2525 Background: Genetically-modified-lymphocytes (GML) can induce a specific immune response against the transgene product (HSV-TK), when injected into immunocompetent patients (Science 276:1719, 1997). In tumor-bearing mice the infusion of tumor-associated-antigen (TAA)-transduced lymphocytes induced protective immunity and long-term memory. In this experimental setting, the T-cell effectors were generated by a cross-presentation pathway, mediated by host dendritic cells (DCs). Indeed, DCs isolated from lymph nodes of treated mice contained fragments of labeled GML and were able to elicit antigen-specific responses ex vivo. Methods: To validate this novel vaccination strategy in humans, we treated 10 patients affected by stage IIIc/IV MAGE-A3+ melanomas with escalating doses of autologous GML expressing MAGE-A3 and the tracer antigen HSV-TK. HSV-TK allows to monitor the immune status of the patients. Immune responses were monitored by DTH and in vitro T cell assays (semi-quantitative recall assays and ELISPOT). Tumor status was monitored by conventional imaging analyses. Results: No toxicity was reported. From the 10 patients, 9 were clinically evaluable because responding to the tracer antigen HSV-TK. We observed one complete response with vitiligo surrounding the lesions and one long lasting stable disease (50 mo). Moreover, one patient with no evidence of disease remained free of disease at >48 mo. The 3 responding patients experienced both DTH reactivity to MAGE-A3 and sustained increase of circulating CD8+ and CD4+ MAGE-A3-specific effectors. The immune response was long lasting since MAGE-A3-specific effectors were still detectable both in vivo and in vitro 1 year after the last vaccination. Conclusions: We describe a new method for in vivo loading of TAA on DCs that may circumvent the limitations of ex vivo manipulation of DCs. Genetically modified lymphocytes, acting as antigen carriers, efficiently target DCs in vivo in tumor-bearing mice and in melanoma patients, resulting in the generation of TAA-specific effectors that correlate with clinical benefit. [Table: see text]

scholarly journals Critical role for Sec22b-dependent antigen cross-presentation in antitumor immunity

2017 ◽  
Vol 214 (8) ◽  
pp. 2231-2241 ◽  
Author(s):  
Andrés Alloatti ◽  
Derek C. Rookhuizen ◽  
Leonel Joannas ◽  
Jean-Marie Carpier ◽  
Salvador Iborra ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Tumor Antigens ◽  
Ex Vivo ◽  
Critical Role ◽  
T Cell Responses ◽  
Cd8 T Cell ◽  
Cross Presentation ◽  
Cell Responses

CD8+ T cells mediate antigen-specific immune responses that can induce rejection of solid tumors. In this process, dendritic cells (DCs) are thought to take up tumor antigens, which are processed into peptides and loaded onto MHC-I molecules, a process called “cross-presentation.” Neither the actual contribution of cross-presentation to antitumor immune responses nor the intracellular pathways involved in vivo are clearly established because of the lack of experimental tools to manipulate this process. To develop such tools, we generated mice bearing a conditional DC-specific mutation in the sec22b gene, a critical regulator of endoplasmic reticulum–phagosome traffic required for cross-presentation. DCs from these mice show impaired cross-presentation ex vivo and defective cross-priming of CD8+ T cell responses in vivo. These mice are also defective for antitumor immune responses and are resistant to treatment with anti–PD-1. We conclude that Sec22b-dependent cross-presentation in DCs is required to initiate CD8+ T cell responses to dead cells and to induce effective antitumor immune responses during anti–PD-1 treatment in mice.

scholarly journals Neutrophil subtypes shape HIV-specific CD8 T-cell responses after vaccinia virus infection

npj Vaccines ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Mauro Di Pilato ◽  
Miguel Palomino-Segura ◽  
Ernesto Mejías-Pérez ◽  
Carmen E. Gómez ◽  
Andrea Rubio-Ponce ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Vaccinia Virus ◽  
Adaptive Immune System ◽  
T Cell Responses ◽  
Cd8 T Cell ◽  
Cell Responses ◽  
Adaptive Immune

AbstractNeutrophils are innate immune cells involved in the elimination of pathogens and can also induce adaptive immune responses. Nα and Nβ neutrophils have been described with distinct in vitro capacity to generate antigen-specific CD8 T-cell responses. However, how these cell types exert their role in vivo and how manipulation of Nβ/Nα ratio influences vaccine-mediated immune responses are not known. In this study, we find that these neutrophil subtypes show distinct migratory and motility patterns and different ability to interact with CD8 T cells in the spleen following vaccinia virus (VACV) infection. Moreover, after analysis of adhesion, inflammatory, and migration markers, we observe that Nβ neutrophils overexpress the α4β1 integrin compared to Nα. Finally, by inhibiting α4β1 integrin, we increase the Nβ/Nα ratio and enhance CD8 T-cell responses to HIV VACV-delivered antigens. These findings provide significant advancements in the comprehension of neutrophil-based control of adaptive immune system and their relevance in vaccine design.

scholarly journals IMMU-31. QUANTITATIVE EVALUATION OF ROUTES OF ADMINISTRATION OF IMMUNOTHERAPEUTIC T CELLS TO ORTHOTOPIC GLIOMA

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii111-ii111
Author(s):  
Lan Hoang-Minh ◽  
Angelie Rivera-Rodriguez ◽  
Fernanda Pohl-Guimarães ◽  
Seth Currlin ◽  
Christina Von Roemeling ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tumor Growth ◽  
Ex Vivo ◽  
Adoptive T Cell Therapy ◽  
Whole Body ◽  
T Cell Therapy ◽  
Clinical Responses

Abstract SIGNIFICANCE Adoptive T cell therapy (ACT) has emerged as the most effective treatment against advanced malignant melanoma, eliciting remarkable objective clinical responses in up to 75% of patients with refractory metastatic disease, including within the central nervous system. Immunologic surrogate endpoints correlating with treatment outcome have been identified in these patients, with clinical responses being dependent on the migration of transferred T cells to sites of tumor growth. OBJECTIVE We investigated the biodistribution of intravenously or intraventricularly administered T cells in a murine model of glioblastoma at whole body, organ, and cellular levels. METHODS gp100-specific T cells were isolated from the spleens of pmel DsRed transgenic C57BL/6 mice and injected intravenously or intraventricularly, after in vitro expansion and activation, in murine KR158B-Luc-gp100 glioma-bearing mice. To determine transferred T cell spatial distribution, the brain, lymph nodes, heart, lungs, spleen, liver, and kidneys of mice were processed for 3D imaging using light-sheet and multiphoton imaging. ACT T cell quantification in various organs was performed ex vivo using flow cytometry, 2D optical imaging (IVIS), and magnetic particle imaging (MPI) after ferucarbotran nanoparticle transfection of T cells. T cell biodistribution was also assessed in vivo using MPI. RESULTS Following T cell intravenous injection, the spleen, liver, and lungs accounted for more than 90% of transferred T cells; the proportion of DsRed T cells in the brains was found to be very low, hovering below 1%. In contrast, most ACT T cells persisted in the tumor-bearing brains following intraventricular injections. ACT T cells mostly concentrated at the periphery of tumor masses and in proximity to blood vessels. CONCLUSIONS The success of ACT immunotherapy for brain tumors requires optimization of delivery route, dosing regimen, and enhancement of tumor-specific lymphocyte trafficking and effector functions to achieve maximal penetration and persistence at sites of invasive tumor growth.

scholarly journals The Ubiquitously Expressed Csk Adaptor Protein Cbp Is Dispensable for Embryogenesis and T-Cell Development and Function

2005 ◽  
Vol 25 (23) ◽  
pp. 10533-10542 ◽  
Author(s):  
Marc-Werner Dobenecker ◽  
Christian Schmedt ◽  
Masato Okada ◽  
Alexander Tarakhovsky
Keyword(s):  
T Cell ◽  
Adaptor Protein ◽  
Regulatory Function ◽  
Loss Of Function ◽  
Thymic Development ◽  
Cell Functions ◽  
Carboxy Terminal ◽  
And Function

ABSTRACT Regulation of Src family kinase (SFK) activity is indispensable for a functional immune system and embryogenesis. The activity of SFKs is inhibited by the presence of the carboxy-terminal Src kinase (Csk) at the cell membrane. Thus, recruitment of cytosolic Csk to the membrane-associated SFKs is crucial for its regulatory function. Previous studies utilizing in vitro and transgenic models suggested that the Csk-binding protein (Cbp), also known as phosphoprotein associated with glycosphingolipid microdomains (PAG), is the membrane adaptor for Csk. However, loss-of-function genetic evidence to support this notion was lacking. Herein, we demonstrate that the targeted disruption of the cbp gene in mice has no effect on embryogenesis, thymic development, or T-cell functions in vivo. Moreover, recruitment of Csk to the specialized membrane compartment of “lipid rafts” is not impaired by Cbp deficiency. Our results indicate that Cbp is dispensable for the recruitment of Csk to the membrane and that another Csk adaptor, yet to be discovered, compensates for the loss of Cbp.

scholarly journals Optimized Adenovirus-Antibody Complexes Stimulate Strong Cellular and Humoral Immune Responses against an Encoded Antigen in Naïve Mice and Those with Preexisting Immunity

2011 ◽  
Vol 19 (1) ◽  
pp. 84-95 ◽  
Author(s):  
Jin Huk Choi ◽  
Joe Dekker ◽  
Stephen C. Schafer ◽  
Jobby John ◽  
Craig E. Whitfill ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Immune Responses ◽  
Neutralizing Antibodies ◽  
T Cell Responses ◽  
Transduction Efficiency ◽  
Virus Antibody ◽  
Cell Responses

ABSTRACTThe immune response to recombinant adenoviruses is the most significant impediment to their clinical use for immunization. We test the hypothesis that specific virus-antibody combinations dictate the type of immune response generated against the adenovirus and its transgene cassette under certain physiological conditions while minimizing vector-induced toxicity.In vitroandin vivoassays were used to characterize the transduction efficiency, the T and B cell responses to the encoded transgene, and the toxicity of 1 × 1011adenovirus particles mixed with different concentrations of neutralizing antibodies. Complexes formed at concentrations of 500 to 0.05 times the 50% neutralizing dose (ND50) elicited strong virus- and transgene-specific T cell responses. The 0.05-ND50formulation elicited measurable anti-transgene antibodies that were similar to those of virus alone (P= 0.07). This preparation also elicited very strong transgene-specific memory T cell responses (28.6 ± 5.2% proliferation versus 7.7 ± 1.4% for virus alone). Preexisting immunity significantly reduced all responses elicited by these formulations. Although lower concentrations (0.005 and 0.0005 ND50) of antibody did not improve cellular and humoral responses in naïve animals, they did promote strong cellular (0.005 ND50) and humoral (0.0005 ND50) responses in mice with preexisting immunity. Some virus-antibody complexes may improve the potency of adenovirus-based vaccines in naïve individuals, while others can sway the immune response in those with preexisting immunity. Additional studies with these and other virus-antibody ratios may be useful to predict and model the type of immune responses generated against a transgene in those with different levels of exposure to adenovirus.

scholarly journals Augmented expansion of Treg cells from healthy and autoimmune subjects via adult progenitor cell co-culture

2020 ◽  
Author(s):  
JL Reading ◽  
VD Roobrouck ◽  
CM Hull ◽  
PD Becker ◽  
J Beyens ◽  
...  
Keyword(s):  
T Cell ◽  
Treg Cell ◽  
Regulatory T Cell ◽  
Cellular Therapy ◽  
Ex Vivo ◽  
Fold Increase ◽  
Adoptive Cellular Therapy ◽  
T Cell Therapy

AbstractRecent clinical experience has demonstrated that adoptive regulatory T cell therapy is a safe and feasible strategy to suppress immunopathology via induction of host tolerance to allo- and autoantigens. However, clinical trials continue to be compromised due to an inability to manufacture a sufficient Treg cell dose. Multipotent adult progenitor cells (MAPCⓇ) promote regulatory T cell differentiation in vitro, suggesting they may be repurposed to enhance ex vivo expansion of Tregs for adoptive cellular therapy. Here, we use a GMP compatible Treg expansion platform to demonstrate that MAPC cell-co-cultured Tregs (MulTreg) exhibit a log-fold increase in yield across two independent cohorts, reducing time to target dose by an average of 30%. Enhanced expansion is linked with a distinct Treg cell-intrinsic transcriptional program, characterized by diminished levels of core exhaustion (BATF, ID2, PRDM1, LAYN, DUSP1), and quiescence (TOB1, TSC22D3) related genes, coupled to elevated expression of cell-cycle and proliferation loci (MKI67, CDK1, AURKA, AURKB). In addition, MulTreg display a unique gut homing (CCR7lo β7hi) phenotype and importantly, are more readily expanded from patients with autoimmune disease compared to matched Treg lines, suggesting clinical utility in gut and/or Th1-driven pathology associated with autoimmunity or transplantation. Relative to expanded Tregs, MulTreg retain equivalent and robust purity, FoxP3 TSDR demethylation, nominal effector cytokine production and potent suppression of Th1-driven antigen specific and polyclonal responses in vitro and xeno graft vs host disease (xGvHD) in vivo. These data support the use of MAPC cell co-culture in adoptive Treg therapy platforms as a means to rescue expansion failure and reduce the time required to manufacture a stable, potently suppressive product.

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