scholarly journals Domain binding and isotype dictate the activity of anti-human OX40 antibodies

2020 ◽  
Vol 8 (2) ◽  
pp. e001557
Author(s):  
Jordana Griffiths ◽  
Khiyam Hussain ◽  
Hannah L Smith ◽  
Theodore Sanders ◽  
Kerry L Cox ◽  
...  

BackgroundPrevious data suggests that anti-OX40 mAb can elicit anti-tumor effects in mice through deletion of Tregs. However, OX40 also has powerful costimulatory effects on T cells which could evoke therapeutic responses. Human trials with anti-OX40 antibodies have shown that these entities are well tolerated but to date have delivered disappointing clinical responses, indicating that the rules for the optimal use of anti-human OX40 (hOX40) antibodies is not yet fully understood. Changes to timing and dosages may lead to improved outcomes; however, here we focus on addressing the role of agonism versus depleting activity in determining therapeutic outcomes. We investigated a novel panel of anti-hOX40 mAb to understand how these reagents and mechanisms may be optimized for therapeutic benefit.MethodsThis study examines the binding activity and in vitro activity of a panel of anti-hOX40 antibodies. They were further evaluated in several in vivo models to address how isotype and epitope determine mechanism of action and efficacy of anti-hOX40 mAb.ResultsBinding analysis revealed the antibodies to be high affinity, with epitopes spanning all four cysteine-rich domains of the OX40 extracellular domain. In vivo analysis showed that their activities relate directly to two key properties: (1) isotype—with mIgG1 mAb evoking receptor agonism and CD8+ T-cell expansion and mIgG2a mAb evoking deletion of Treg and (2) epitope—with membrane-proximal mAb delivering more powerful agonism. Intriguingly, both isotypes acted therapeutically in tumor models by engaging these different mechanisms.ConclusionThese findings highlight the significant impact of isotype and epitope on the modulation of anti-hOX40 mAb therapy, and indicate that CD8+ T-cell expansion or Treg depletion might be preferred according to the composition of different tumors. As many of the current clinical trials using OX40 antibodies are now using combination therapies, this understanding of how to manipulate therapeutic activity will be vital in directing new combinations that are more likely to improve efficacy and clinical outcomes.

2005 ◽  
Vol 201 (1) ◽  
pp. 139-148 ◽  
Author(s):  
Rong Zeng ◽  
Rosanne Spolski ◽  
Steven E. Finkelstein ◽  
SangKon Oh ◽  
Panu E. Kovanen ◽  
...  

Interleukin (IL)-21 is the most recently recognized of the cytokines that share the common cytokine receptor γ chain (γc), which is mutated in humans with X-linked severe combined immunodeficiency. We now report that IL-21 synergistically acts with IL-15 to potently promote the proliferation of both memory (CD44high) and naive (CD44low) phenotype CD8+ T cells and augment interferon-γ production in vitro. IL-21 also cooperated, albeit more weakly, with IL-7, but not with IL-2. Correspondingly, the expansion and cytotoxicity of CD8+ T cells were impaired in IL-21R−/− mice. Moreover, in vivo administration of IL-21 in combination with IL-15 boosted antigen-specific CD8+ T cell numbers and resulted in a cooperative effect on tumor regression, with apparent cures of large, established B16 melanomas. Thus, our studies reveal that IL-21 potently regulates CD8+ T cell expansion and effector function, primarily in a synergistic context with IL-15.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2974-2974
Author(s):  
Xiaofan Li ◽  
Wei He ◽  
Ruishu Deng ◽  
Can Liu ◽  
Miao Wang ◽  
...  

Abstract Abstract 2974 Alloreactive donor CD8+ T cells facilitate engraftment and mediate graft versus leukemia (GVL) effects but also cause graft versus host disease (GVHD) in murine and human recipients after allogeneic hematopoietic cell transplantation (HCT). B7-H1 (PD-L1) expression by antigen-presenting cells has an important role in tolerizing activated T cells by binding to PD-1. We and others previously reported that disruption of binding between B7-H1 and PD-1 augments acute GVHD. Parenchymal cells do not usually express B7-H1 but can be induced by inflammatory cytokines (i.e. IFN-g) to express B7-H1. The role of B7-H1 expression by parenchymal tissue cells in regulating the expansion and persistence of donor CD8+ cells in tissues of mice with GVHD has not yet been evaluated. In the current studies, we evaluated the role of B7-H1 expression by GVHD target tissues in regulating donor CD8+ T cell function in 3 different experimental GVHD systems, using in vivo bioluminescent imaging (BLI), in vivo BrdU-labeling, and in vitro proliferation assays. The first system evaluated the role of B7-H1 expression in TBI-conditioned recipients. In these recipients, injected donor CD8+ T cells showed two waves of expansion that correlated with two phases of clinical GVHD. The first wave of donor CD8+ T cell expansion was associated with upregulated expression of B7-H1 in GVHD target tissues and only weak clinical GVHD. The second wave of donor CD8+ T cell expansion was associated with loss of B7-H1 expression, vigorous donor CD8+ T proliferation and expansion in the GVHD target tissues, and lethal GVHD. In a gain-of-function experiment, B7-H1 expression was induced in hepatocytes by hydrodynamic injection of B7-H1 cDNA during the second wave of T cell expansion in mice with GVHD; this subsequently decreased T cell expansion in the liver and ameliorated GVHD. The second system evaluated the role of B7-H1 expression in anti-CD3-conditioned recipients. In wild-type recipients, injected donor CD8+ T cells had only a single wave of expansion, and the mice had no signs of GVHD. B7-H1 expression by tissue cells (i.e. hepatocytes) was up-regulated, and the tissue infiltrating donor CD8+ T cells were anergic. In B7-H1−/− recipients, injected donor CD8+ T cells proliferated vigorously in GVHD target tissues and caused lethal GVHD.The third system evaluated the role of B7-H1 in unconditioned Rag-2−/− recipients after administration of blocking anti-B7-H1 and in the B7-H1−/−Rag-2−/− chimeras with B7-H1 sufficient Rag-2−/− bone marrow cells, in which B7-H1 deficiency was only in tissue parenchymal cells. Both blockade of B7-H1 and B7-H1 deficiency in parenchymal cells resulted in vigorous donor CD8+ T proliferation in GVHD target tissues and caused lethal GVHD. Taken together, these results show that expression of B7-H1 in GVHD target tissue parenchymal cells plays an important role in regulating the proliferation of infiltrating donor CD8+ T cells and preventing the persistence of GVHD. Our studies also indicate that TBI but not anti-CD3 conditioning can lead to loss of GVHD target tissue cell expression of B7-H1 and persistence of GVHD. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2008 ◽  
Vol 112 (5) ◽  
pp. 1759-1766 ◽  
Author(s):  
Peter N. Lalli ◽  
Michael G. Strainic ◽  
Min Yang ◽  
Feng Lin ◽  
M. Edward Medof ◽  
...  

Abstract Our recent studies have shown that immune cell–produced complement provides costimulatory and survival signals to naive CD4+ T cells. Whether these signals are similarly required during effector cell expansion and what molecular pathways link locally produced complement to T-cell survival were not clarified. To address this, we stimulated monoclonal and polyclonal T cells in vitro and in vivo with antigen-presenting cells (APCs) deficient in the complement regulatory protein, decay accelerating factor (DAF), and/or the complement component C3. We found that T-cell expansion induced by DAF-deficient APCs was augmented with diminished T-cell apoptosis, whereas T-cell expansion induced by C3−/− APCs was reduced because of enhanced T-cell apoptosis. These effects were traced to locally produced C5a, which through binding to T cell–expressed C5aR, enhanced expression of Bcl-2 and prevented Fas up-regulation. The results show that C5aR signal transduction in T cells is important to allow optimal T-cell expansion, as well as to maintain naive cell viability, and does so by suppressing programmed cell death.


Viruses ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 639 ◽  
Author(s):  
Younghyun Lim ◽  
Seyoung Kim ◽  
Sehoon Kim ◽  
Dong-In Kim ◽  
Kyung Won Kang ◽  
...  

The immune-suppressive effects of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) on T cells have been observed via multiple in vitro and in vivo models. However, the precise mechanism that causes these effects is still undefined. In this study, we investigated whether n-3 PUFAs regulated T cell receptor (TCR) and peptide-major histocompatibility complex (pMHC) interactions. The expansion of anti-viral CD8+ T cells that endogenously synthesize n-3 PUFAs (FAT-1) dramatically decreased upon lymphocytic choriomeningitis virus (LCMV) infection in vivo. This decrease was not caused by the considerable reduction of TCR expression or the impaired chemotactic activity of T cells. Interestingly, a highly inclined and laminated optical sheet (HILO) microscopic analysis revealed that the TCR motility was notably reduced on the surface of the FAT-1 CD8+ T cells compared to the wild type (WT) CD8+ T cells. Importantly, the adhesion strength of the FAT-1 CD8+ T cells to the peptide-MHC was significantly lower than that of the WT CD8+T cells. Consistent with this result, treatment with docosahexaenoic acid (DHA), one type of n-3 PUFA, significantly decreased CD8+ T cell adhesion to the pMHC. Collectively, our results reveal a novel mechanism through which n-3 PUFAs decrease TCR-pMHC interactions by modulating TCR mobility on CD8+ T cell surfaces.


1996 ◽  
Vol 8 (4) ◽  
pp. 519-523 ◽  
Author(s):  
Matthew F. Krummel ◽  
Timothy J. Sullivan ◽  
James P. Allison

2006 ◽  
Vol 314 (1-2) ◽  
pp. 147-152 ◽  
Author(s):  
Linda D. Barber ◽  
Susan Jordan ◽  
Alison M.E. Whitelegg ◽  
J. Alejandro Madrigal ◽  
Philip Savage

2012 ◽  
Vol 109 (31) ◽  
pp. 12698-12703 ◽  
Author(s):  
J.-s. Do ◽  
A. Valujskikh ◽  
D. A. A. Vignali ◽  
R. L. Fairchild ◽  
B. Min

2020 ◽  
Author(s):  
Jordana Griffiths ◽  
Khiyam Hussain ◽  
Hannah L Smith ◽  
Theodore Sanders ◽  
Kerry Cox ◽  
...  

AbstractPrevious data suggests that anti-OX40 mAb can elicit anti-tumour effects in mice through deletion of Tregs. However, OX40 also has powerful costimulatory effects on T cells which could evoke therapeutic responses. The contributions of these different effector mechanisms has not previously been systematically evaluated, particularly for mAb directed to human OX40. Therefore, we generated a novel human OX40 knock-in (KI) mouse to evaluate a panel of anti-hOX40 mAb and show that their activities relate directly to two key properties: 1) isotype – with mIgG1 mAb evoking receptor agonism and CD8+ T cell expansion and mIgG2a mAb evoking deletion of Treg and; 2) epitope - with membrane-proximal mAb delivering more powerful agonism. Intriguingly, both isotypes acted therapeutically in tumour models by engaging these different mechanisms. These findings highlight the significant impact of isotype and epitope on the modulation of anti-hOX40 mAb therapy, and indicate that CD8+ T cell expansion or Treg depletion might be preferable according to the composition of different tumours.SummaryHuman trials with anti-OX40 antibodies have been disappointing indicating that optimal reagents have not yet been developed. Here, using a new panel of antibodies, we show that isotype and epitope combine to determine agonistic and therapeutic activity.


Sign in / Sign up

Export Citation Format

Share Document