The targeted delivery of therapeutic drugs to lymph nodes (LNs) provides an unprecedented opportunity to improve the outcomes of transplantation and immune-mediated diseases. The high endothelial venule is a specialized segment of LN vasculature that uniquely expresses peripheral node addressin (PNAd) molecules. PNAd is recognized by MECA79 mAb. We previously generated a MECA79 mAb–coated microparticle (MP) that carries tacrolimus. Although this MP trafficked to LNs, it demonstrated limited therapeutic efficacy in our transplant model. Here, we have synthesized a nanoparticle (NP) as a carrier of anti-CD3, and optimized the conjugation strategy to coat the NP surface with MECA79 mAb (MECA79-anti-CD3-NP) to enhance LN accumulation. As compared with nonconjugated NPs, a significantly higher quantity of MECA79-NPs accumulated in the draining lymph node (DLN). Many MECA79-NPs underwent internalization by T cells and dendritic cells within the LNs. Short-term treatment of murine cardiac allograft recipients with MECA79-anti-CD3-NP resulted in significantly prolonged allograft survival in comparison with the control groups. Prolonged graft survival following treatment with MECA79-anti-CD3-NP was characterized by a significant increase in intragraft and DLN Treg populations. Treg depletion abrogated the prolongation of heart allograft survival. We believe this targeted approach of drug delivery could redefine the methods of administering immune therapeutics in transplantation.
Baharak Bahmani, Mayuko Uehara, Liwei Jiang, Farideh Ordikhani, Naima Banouni, Takaharu Ichimura, Zhabiz Solhjou, Georg J. Furtmüller, Gerald Brandacher, David Alvarez, Ulrich H. von Andrian, Kenji Uchimura, Qiaobing Xu, Ishaan Vohra, Osman A. Yilmam, Yousef Haik, Jamil Azzi, Vivek Kasinath, Jonathan S. Bromberg, Martina M. McGrath, Reza Abdi
Chronic lymphocytic leukemia (CLL) is characterized by clonal proliferation and progressive accumulation of mature, B lymphocytes in the peripheral blood, lymphoid tissues and bone marrow. CLL is characterized by profound immune defects, leading to severe infectious complications. T cells are numerically, phenotypically, and functionally highly abnormal in CLL, with only limited ability to exert antitumor immune responses. Exhaustion of T cells has also been implicated as playing an important role in anti-tumor responses. The CLL-mediated T cell exhaustion is achieved by aberrant expression of several inhibitory molecules on CLL and their environment, prominently the PD-L1/PD-1 receptors. Previously, we showed that CD84, a member of the SLAM family of receptors, bridges between CLL cells and their microenvironment. In the current study, we followed CD84 regulation of T cell function. We showed that a cell-cell interaction mediated through human and mouse CD84 upregulates PDL1 expression on CLL and their microenvironment, and PD1 expression on T cells. This resulted in suppression of T cell response and activity in vitro and in vivo. Thus, our results demonstrated a role for CD84 in regulation of immune checkpoints by leukemia cells, and suggested CD84 blockade as a therapeutic strategy to reverse tumor-induced immune suppression.
Hadas Lewinsky, Avital F. Barak, Victoria Huber, Matthias P. Kramer, Lihi Radomir, Lital Sever, Irit Orr, Vita Mirkin, Nili Dezorella, Mika Shapiro, Yosef Cohen, Lev Shvidel, Martina Seiffert, Yair Herishanu, Shirly Becker-Herman, Idit Shachar
Allergic asthma is characterized by airway hyperresponsiveness, inflammation, and a cellular infiltrate dominated by eosinophils. Numerous epidemiological studies have related the exacerbation of allergic asthma with an increase in ambient inhalable particulate matter from air pollutants. This is because inhalable particles efficiently deliver airborne allergens deep into the airways, where they can aggravate allergic asthma symptoms. However, the cellular mechanisms by which inhalable particulate allergens (pAgs) potentiate asthmatic symptoms remain unknown, in part because most in vivo and in vitro studies exploring the pathogenesis of allergic asthma use soluble allergens (sAgs). Using a mouse model of allergic asthma, we found that, compared with their sAg counterparts, pAgs triggered markedly heightened pulmonary eosinophilia in allergen-sensitized mice. Mast cells (MCs) were implicated in this divergent response, as the differences in airway inflammatory responses provoked by the physical nature of the allergens were attenuated in MC-deficient mice. The pAgs were found to mediate MC-dependent responses by enhancing retention of pAg/IgE/FcεRI complexes within lipid raft–enriched, CD63+ endocytic compartments, which prolonged IgE/FcεRI-initiated signaling and resulted in heightened cytokine responses. These results reveal how the physical attributes of allergens can co-opt MC endocytic circuitry and signaling responses to aggravate pathological responses of allergic asthma in mice.
Cong Jin, Christopher P. Shelburne, Guojie Li, Kristina J. Riebe, Gregory D. Sempowski, W. Michael Foster, Soman N. Abraham
The accrual of myeloid-derived suppressor cells (MDSCs) represents a major obstacle to effective immunotherapy in cancer patients, but the mechanisms underlying this process in the human setting remain elusive. Here, we describe a set of microRNAs (miR-146a, miR-155, miR-125b, miR-100, let-7e, miR-125a, miR-146b, miR-99b) that are associated with MDSCs and with resistance to treatment with immune checkpoint inhibitors in melanoma patients. The miRs were identified by transcriptional analyses as being responsible for the conversion of monocytes into MDSCs (CD14+HLA-DRneg cells) mediated by melanoma extracellular vesicles (EVs) and were shown to recreate MDSC features upon transfection. In melanoma patients, these miRs are increased in circulating CD14+ monocytes, plasma and tumor samples, where they correlate with the myeloid cell infiltrate. In plasma, their baseline level clusters with the clinical efficacy of CTLA-4 or PD-1 blockade. Hence, MDSC-related miRs represent an indicator of MDSC activity in cancer patients and a potential blood marker of a poor immunotherapy outcome.
Veronica Huber, Viviana Vallacchi, Viktor Fleming, Xiaoying Hu, Agata Cova, Matteo Dugo, Eriomina Shahaj, Roberta Sulsenti, Elisabetta Vergani, Paola Filipazzi, Angela De Laurentiis, Luca Lalli, Lorenza Di Guardo, Roberto Patuzzo, Barbara Vergani, Elena Casiraghi, Mara Cossa, Ambra Gualeni, Valentina Bollati, Flavio Arienti, Filippo De Braud, Luigi Mariani, Antonello Villa, Peter Altevogt, Viktor Umansky, Monica Rodolfo, Licia Rivoltini
The resolution of inflammation is an active process that is coordinated by endogenous mediators. Previous studies have demonstrated the immunomodulatory properties of the axonal guidance proteins in the initial phase of acute inflammation. We hypothesized that the neuronal guidance protein neogenin (Neo1) modulates mechanisms of inflammation resolution. In murine peritonitis, Neo1 deficiency (Neo1–/–) resulted in higher efficacies in reducing neutrophil migration into injury sites, increasing neutrophil apoptosis, actuating PMN phagocytosis, and increasing the endogenous biosynthesis of specialized proresolving mediators, such as lipoxin A4, maresin-1, and protectin DX. Neo1 expression was limited to Neo1-expressing Ly6Chi monocytes, and Neo1 deficiency induced monocyte polarization toward an antiinflammatory and proresolving phenotype. Signaling network analysis revealed that Neo1–/– monocytes mediate their immunomodulatory effects specifically by activating the PI3K/AKT pathway and suppressing the TGF-β pathway. In a cohort of 59 critically ill, intensive care unit (ICU) pediatric patients, we found a strong correlation between Neo1 blood plasma levels and abdominal compartment syndrome, Pediatric Risk of Mortality III (PRISM-III) score, and ICU length of stay and mortality. Together, these findings identify a crucial role for Neo1 in regulating tissue regeneration and resolution of inflammation, and determined Neo1 to be a predictor of morbidity and mortality in critically ill children affected by clinical inflammation.
Martin Schlegel, Andreas Körner, Torsten Kaussen, Urs Knausberg, Carmen Gerber, Georg Hansmann, Hulda Soffia Jónasdóttir, Martin Giera, Valbona Mirakaj
Interrupting T cell costimulatory signals as a strategy to control undesired immune responses, such as occur in autoimmunity or transplantation, has the potential to alleviate many of the unwanted side effects associated with current immunosuppressive therapies. Belatacept, a high-affinity version of CTLA4-Ig that blocks ligand ligation to CD28, has been approved for use in kidney transplant recipients. Despite the long-term benefits associated with its use, such as improved renal function and lower cardiovascular risk, a subset of patients treated with belatacept experience elevated rates of acute T cell–mediated rejection, tempering enthusiasm for its use. Here we demonstrate that costimulation-independent T cell alloreactivity relies on signaling through CD122, the shared IL-2 and IL-15 receptor β-chain. Combined costimulatory and CD122 blockade improved survival of transplanted tissue in mice and nonhuman primates by controlling proliferation and effector function of CD8+ T cells. The high-affinity IL-2 receptor was dispensable for memory CD8+ T cell responses, whereas signaling through CD122 as a component of the high-affinity IL-15 receptor was critical for costimulation-independent memory CD8+ T cell recall, distinguishing specific roles for IL-2 and IL-15 in T cell activation. These studies outline a novel approach for clinical optimization of costimulatory blockade strategies in transplantation by targeting CD122.
David V. Mathews, Ying Dong, Laura B. Higginbotham, Steven C. Kim, Cynthia P. Breeden, Elizabeth A. Stobert, Joseph Jenkins, J. Yun Tso, Christian P. Larsen, Andrew B. Adams
Checkpoint blockade immunotherapy targeting the PD-1/PD-L1 inhibitory axis has produced remarkable results in the treatment of several types of cancer. Whereas cytotoxic T cells are known to provide important antitumor effects during checkpoint blockade, certain cancers with low MHC expression are responsive to therapy, suggesting that other immune cell types may also play a role. Here, we employed several mouse models of cancer to investigate the effect of PD-1/PD-L1 blockade on NK cells, a population of cytotoxic innate lymphocytes that also mediate antitumor immunity. We discovered that PD-1 and PD-L1 blockade elicited a strong NK cell response that was indispensable for the full therapeutic effect of immunotherapy. PD-1 was expressed on NK cells within transplantable, spontaneous, and genetically induced mouse tumor models, and PD-L1 expression in cancer cells resulted in reduced NK cell responses and generation of more aggressive tumors in vivo. PD-1 expression was more abundant on NK cells with an activated and more responsive phenotype and did not mark NK cells with an exhausted phenotype. These results demonstrate the importance of the PD-1/PD-L1 axis in inhibiting NK cell responses in vivo and reveal that NK cells, in addition to T cells, mediate the effect of PD-1/PD-L1 blockade immunotherapy.
Joy Hsu, Jonathan J. Hodgins, Malvika Marathe, Chris J. Nicolai, Marie-Claude Bourgeois-Daigneault, Troy N. Trevino, Camillia S. Azimi, Amit K. Scheer, Haley E. Randolph, Thornton W. Thompson, Lily Zhang, Alexandre Iannello, Nikhita Mathur, Karen E. Jardine, Georgia A. Kirn, John C. Bell, Michael W. McBurney, David H. Raulet, Michele Ardolino
Fibroblast-like synoviocytes (FLSs) are critical to synovial aggression and joint destruction in rheumatoid arthritis (RA). The role of long noncoding RNAs (lncRNAs) in RA is largely unknown. Here, we identified a lncRNA, LERFS (lowly expressed in rheumatoid fibroblast-like synoviocytes), that negatively regulates the migration, invasion, and proliferation of FLSs through interaction with heterogeneous nuclear ribonucleoprotein Q (hnRNP Q). Under healthy conditions, by binding to the mRNA of RhoA, Rac1, and CDC42 — the small GTPase proteins that control the motility and proliferation of FLSs — the LERFS–hnRNP Q complex decreased the stability or translation of target mRNAs and downregulated their protein levels. But in RA FLSs, decreased LERFS levels induced a reduction of the LERFS–hnRNP Q complex, which reduced the binding of hnRNP Q to target mRNA and therefore increased the stability or translation of target mRNA. These findings suggest that a decrease in synovial LERFS may contribute to synovial aggression and joint destruction in RA and that targeting the lncRNA LERFS may have therapeutic potential in patients with RA.
Yaoyao Zou, Siqi Xu, Youjun Xiao, Qian Qiu, Maohua Shi, Jingnan Wang, Liuqin Liang, Zhongping Zhan, Xiuyan Yang, Nancy Olsen, Song Guo Zheng, Hanshi Xu
Chronic inflammatory diseases are characterized by recurrent inflammatory attacks in the tissues mediated by autoreactive T cells. Identity and functional programming of CD8+ T cells at the target site of inflammation still remain elusive. One key question is whether, in these antigen-rich environments, chronic stimulation leads to CD8+ T cell exhaustion comparable to what is observed in infectious disease contexts. In the synovial fluid (SF) of juvenile idiopathic arthritis (JIA) patients, a model of chronic inflammation, an overrepresentation of PD-1+CD8+ T cells was found. Gene expression profiling, gene set enrichment analysis, functional studies, and extracellular flux analysis identified PD-1+CD8+ T cells as metabolically active effectors, with no sign of exhaustion. Furthermore, PD-1+CD8+ T cells were enriched for a tissue-resident memory (Trm) cell transcriptional profile and demonstrated increased clonal expansion compared with the PD-1– counterpart, suggesting antigen-driven expansion of locally adapted cells. Interestingly, this subset was also found increased in target tissues in other human chronic inflammatory diseases. These data indicate that local chronic inflammation drives the induction and expansion of CD8+ T cells endowed with potential detrimental properties. Together, these findings lay the basis for investigation of PD-1–expressing CD8+ T cell targeting strategies in human chronic inflammatory diseases.
Alessandra Petrelli, Gerdien Mijnheer, David P. Hoytema van Konijnenburg, Maria M. van der Wal, Barbara Giovannone, Enric Mocholi, Nadia Vazirpanah, Jasper C. Broen, Dirkjan Hijnen, Bas Oldenburg, Paul J. Coffer, Sebastian J. Vastert, Berent J. Prakken, Eric Spierings, Aridaman Pandit, Michal Mokry, Femke van Wijk
Despite the success of T cell checkpoint blockade against melanoma, many “cold” tumors such as prostate cancer remain unresponsive. We find that hypoxic zones are prevalent across pre-clinical prostate cancer and resist T cell infiltration even in the context of CTLA-4 and PD-1 blockade. We show that the hypoxia-activated prodrug TH-302 reduces or eliminates hypoxia in these tumors. Combination therapy with this hypoxia-prodrug and checkpoint blockade cooperate to cure more than 80% of TRAMP-C2 prostate tumors. Immunofluorescence imaging shows that TH-302 drives an influx of T cells into hypoxic zones, which are then amplified by checkpoint blockade. Further, combination therapy reduces myeloid-derived suppressor cell density by more than 50%, and causes a persistent defect in the capacity of the tumor to replenish the granulocytic subset. Spontaneous prostate tumors in TRAMP transgenic mice, which are completely resistant to checkpoint blockade, show minimal adenocarcinoma tumor burden at 36 weeks of age and no evidence of neuroendocrine tumors. Survival of Pb-Cre4, Ptenpc−/−Smad4pc−/− mice with highly aggressive prostate adenocarcinoma is also significantly extended by the combination of hypoxia-prodrug and checkpoint blockade. This combination of hypoxia disruption and T cell checkpoint blockade may render some of the most therapeutically resistant cancers sensitive to immunotherapy.
Priyamvada Jayaprakash, Midan Ai, Arthur Liu, Pratha Budhani, Todd Bartkowiak, Jie Sheng, Casey R. Ager, Courtney Nicholas, Ashvin R. Jaiswal, Yanqiu Sun, Krishna Shah, Sadhana Balasubramanyam, Nan Li, Guocan Wang, Jing Ning, Anna Zal, Tomasz Zal, Michael A. Curran