Functional Reversion of Antigen-Specific CD8+ T Cells from Patients with Hodgkin Lymphoma following In Vitro Stimulation with Recombinant Polyepitope

Abstract

Recent studies on Hodgkin’s lymphoma (HL) have indicated that patients with active disease display functional impairment of Ag-specific CD8+ T cells due to expansion of regulatory T cells at sites of disease and in the peripheral blood. Adoptive cellular immunotherapy based on EBV-specific CD8+ T cells has been explored with limited success to date. It has been proposed that improved targeting of these CD8+ T cells toward viral Ags that are expressed in HL may enhance future therapeutic vaccine strategies. In this study, we have developed a novel replication-deficient adenoviral Ag presentation system that is designed to encode glycine alanine repeat-deleted EBV nuclear Ag 1 covalently linked to multiple CD8+ T cell epitopes from latent membrane proteins 1 and 2. A single stimulation of CD8+ T cells from healthy virus carriers, and patients with HL with this adenoviral construct in combination with IL-2, was sufficient to reverse the functional T cell impairment and restored both IFN-γ production and cytolytic function. More importantly, these activated CD8+ T cells responded to tumor cells expressing membrane proteins and recognized novel EBNA1 epitopes. Flow cytometric analysis revealed that a large proportion of T cells expanded from patients with HL were CD62Lhigh and CD27high, and CCR7low, consistent with early to mid effector T cells. These findings provide an important platform for translation of Ag-specific adoptive immunotherapy for the treatment of EBV-associated malignancies such as HL and nasopharyngeal carcinoma.

Epstein-Barr Virus-Associated Classical Hodgkin Lymphoma and Its Therapeutic Strategies

“…These modifi cations dramatically enhanced intracellular degradation of the protein and restored CD8+ T cell recognition, demonstrating that GAr-mediated proteosomal blockade on EBNA1 can be reversed (Tellam et al, 2001). Moreover, it was demonstrated that CD8 T cells from patients with HL were successfully stimulated in vitro with a construct containing a GAr-deleted EBNA1, reversing the functional T cell impairment as well as responding to tumor cells expressing EBNA1 (Smith et al, 2006). Currently, it is not easy to discover a therapeutic drug that specifi cally modulates the degradation of EBNA1.…”

“…In addition, an exposure to a replication-defi cient adenoviral system with polyepitopes from LMP1 or LMP2 induced effective expanding of specifi c T cells. HL patients with this adenoviral construct in combination with IL-2, were suffi cient to reverse the functional T cell impairment and restored cytolytic function (Smith et al, 2006). Like EBNA1, LMP1 molecules can be effi ciently presented via cotranslational ubiquitination combined with N-end rule targeting.…”

“…Nt (Ho et al, 1999;Komano et al, 1999;Kitagawa et al, 2000;Yamamoto et al., 2000;Iwakiri et al, 2003;Iwakiri et al, 2005;Samanta et al, 2006;Samanta et al, 2008;Iwakiri et al, 2009;Iwakiri and Takada, 2010 Immunization with LMP1 gene or polyepitope expression vectors Taylor et al, 2004;Smith et al, 2006;Pan et al, 2009;Lutzky et al, 2010;Chia et al, Immunization with LMP2A gene or polyepitope expression vectors (Taylor et al, 2004;Smith et al, 2006;Pan et al, 2009;Lutzky et al, 2010;Chia et al, 2011) LMP2B Modulation of innate immune response nt TLR: Toll-like receptor, RIG: retinoic acid-inducible gene, PKR: RNA-dependent protein kinase, Nt: not tested, CTL: cytotoxic T lymphocyte, DC: dendritic cells.…”

Differential Outcome of IL-2/Anti–IL-2 Complex Therapy on Effector and Memory CD8+ T Cells following Vaccination with an Adenoviral Vector Encoding EBV Epitopes

“…Six-to 8-wk-old mice were immunized i.p. with 10 10 PFU AdE1-LMPpoly, which encodes EBV latent membrane protein (LMP) 1 and LMP2 epitopes covalently linked to a truncated sequence of EBNA1 without the glycine-alanine repeat (14). Mice were then treated with three i.p.…”

“…It is currently unclear the precise impact IL-2 complex treatment has upon these phenotypically distinct populations of T cells. In this study, we have employed IL-2 complexes in combination with an adenoviralbased EBV vaccine (referred to as AdE1-LMPpoly) (14,15) to investigate its impact on the Ag-specific effector and central memory responses generated from an endogenous naive CD8 + T cell population. These studies revealed that T cells were unresponsive to IL-2 complex treatment during the early priming phase, whereas delivery of these complexes following the establishment of a memory response preferentially enhanced the expansion of Ag-specific central memory T cells.…”