Safety and Clinical Response to Combined Immunotherapy with Autologous iNKT Cells and PD-1+CD8+ T Cells in Patients Failing First-line Chemotherapy in Stage IV Pancreatic Cancer.

Purpose: A phase I clinical trial was conducted to assess the safety and feasibility of invariant natural killer T (iNKT) cells combined with PD-1+CD8+ T cells in patients with advanced pancreatic cancer and failing the first-line chemotherapy. Patients and Methods: Fifteen eligible patients were enrolled, of whom 9 received at least three cycles of treatment each. In total, 59 courses were administered. Results: Fever was the most common adverse event, peaking at about 2-4 hours after cell infusion and reverting within 24 hours without treatment in all patients. Influenza-like reactions such as headache, myalgia, and arthralgia were also observed in 4, 4, and 3 of the patients, respectively. In addition, vomiting and dizziness were prevalent, while abdominal pain, chest pain, rash, and stuffy nose were rare adverse events, each reported in 1 patient. Side effects above grade 2 were not observed. Two patients achieved partial regression, while 1 patient experienced disease progression assessed 4 weeks after the third course. Three patients are still alive at the time of writing and have progression-free survival longer than 12 months. The overall survival time has been extended to over 12 months in 6 of the 9 patients. No constant changes of CD4+ T, B, and NK cells were recorded except for elevated CD8+ T cells after the first course. Conclusions: The combination of autologous iNKT cells and PD-1+CD8+ T cells was a safe therapeutic strategy against advanced pancreatic cancer. The patients exhibited a potentially promising prolonged survival time. Further study appears warranted to evaluate the efficacy of these combined cell infusions in pancreatic cancer. Trial registration: This trial was included in the clinical trial which was registered in ClinicalTrials.gov (ID:NCT03093688) on March 15, 2017. Significance: There is an unmet need for novel, more effective, and tolerable therapies for pancreatic cancer. Here we present a phase I clinical trial employing iNKT cells combined with PD-1+CD8+ T cells in 9 patients with advanced pancreatic cancer and failing the first-line chemotherapy. The combined immunotherapy was shown to be feasible in the enrolled patients with limited side effects and optimistic clinical responses, which could bring opportunity of therapeutic advancement.

Improving the ex vivo expansion of human tumor-reactive CD8 + T cells by targeting toll-like receptors.

Toll-like receptors (TLRs) are important pattern recognition receptor(s) known to mediate the sensing of invading pathogens and subsequent immune responses. In this study, we investigate whether TLRs could be explored for the preparation of human CD8+ T cell products used in adoptive cell therapy (ACT). Following characterization of TLRs expression on human CD8+ T cells, we screened TLR-specific agonists for their ability to act in concert with anti-CD3 to stimulate the proliferation of these cells and corroborated the observed co-stimulatory effect by transcriptional profiling analyses. Consequently, we developed an optimal formulation for human CD8+ T cell amplification by combining CD3/CD28 antibody, interleukin 7 (IL-7), interleukin 15 (IL-15), and three agonists respectively targeting TLR1/2, TLR2/6, and TLR5. This new formulation performed better in amplifying PD-1+CD8+ T cells, a potential repertoire of tumor-reactive CD8+ T cells, from tumor patients than the conventional formulation. Importantly, the expanded CD8+ T cells showed restored functionality and consequently a robust anti-tumor activity in an in vitro co-culturing system. Together, our study established the utility of TLR agonists in ex vivo expansion of tumor-targeting CD8+ T cells, thus providing a new avenue toward a more effective ACT.

Pathologically complete remission to combination of invariant NK T cells and anti-CD20 antibody in a refractory HIV+ diffuse large B-cell lymphoma patient.

Although there is a high curability rate with rituximab chemotherapy, approximately 40% of patients with diffuse large B-cell lymphoma (DLBCL) develop disease relapse or primary-refractory lymphoma. The prognosis of HIV+ DLBCL patients is even worse with limited therapeutic options. The case is presented of a 28-year-old man who was diagnosed with HIV-DLBCL, refractory to rituximab-based chemo-immunotherapies and radiotherapy before and maintained a pathologically complete regression with the infusion of haplotype-matched invariant NK T cells and anti-CD20 antibody. His abdominal mass kept shrinking during the period of follow-up without relapse to date. A combination of haplotype-matched invariant NK T cells was likely to reinvigorate the efficacy of anti-CD20 antibody and may offer a viable treatment option for refractory DLBCL patients.

Diffuse large B-cell lymphoma (DLBCL) is one of the most frequent types of lymphoid cancer. The prognosis of relapsed/refractory DLBCL patients has been dismal with resistance to rituximab-based chemo-immunotherapy. The combination of effective cells with rituximab might improve clinical response by enhancing antibody-dependent cytotoxicity. The authors reported the case of a 28-year-old man diagnosed with HIV-DLBCL, refractory to 3 lines of rituximab-based chemo-immunotherapies and radiotherapy before, and who received 6 experimental infusions of haplotype-matched invariant NK T cells combined with anti-CD20 antibody. The lesion on radiological examination was partially regressed after cycle 3 and cycle 6. The pathological examination, performed 4 weeks after cycle 6, suggested pathologically complete regression. The mass was completely regressed on CT scanning without relapse to date. A combination of invariant NK T cells and anti-CD20 antibody may offer a viable treatment option for relapsed/refractory DLBCL patients for whom rituximab chemotherapy was not effective.

Feasibility of iNKT cell and PD-1+CD8+ T cell-based immunotherapy in patients with lung adenocarcinoma: Preliminary results of a phase I/II clinical trial.

We performed a single-arm exploratory clinical trial that is ongoing and registered at ClinicalTrials.gov (NCT03093688). Patients were infused with autologous iNKT cells, PD-1 + CD8+ T cells, and dendritic cells every 3-5 weeks, which was considered 1 cycle. The primary endpoints were safety and objective tumor response. The preliminary results from the first three patients are reported here. The first patient received 16 cycles. Computed tomography (CT) examination revealed a stable disease (SD) response after 4 cycles and progressive disease (PD) response after 11 cycles. For the second patient that received 10 cycles, CT examination revealed an SD response after 4 cycles and a PD response after 9 cycles. For the third patient who was treated with 6 cycles, CT examination revealed an SD response after 4 cycles. The patients suffered from only grade 1-2 adverse events. iNKT cell and PD-1 + CD8+ T cell-based immunotherapy showed a manageable tolerability profile.

A new model of self-resolving leptospirosis in mice infected with a strain of Leptospira interrogans serovar Autumnalis harboring LPS signaling only through TLR4.

Leptospirosis is an emerging worldwide zoonosis caused by pathogenic Leptospira spp. Our understanding of leptospirosis pathogenesis and host immune response remains limited, while mechanistic studies are hindered by a lack of proper animal models and immunological reagents. Here we established a murine model of acute and self-resolving leptospirosis by infecting 10-week-old C57BL/6 mice with Leptospira interrogans serovar Autumnalis strain 56606v, with characteristic manifestations including jaundice as well as subcutaneous and pulmonary bleeding, but no kidney lesions. We also verified that the lipopolysaccharide (LPS) of strain 56606v signaled through a TLR4-dependent pathway in murine bone marrow-derived macrophages (BMDMs), rather than the previously reported TLR2. In addition, upon infection with Leptospira strain 56606v, TLR4-/- C57BL/6 mice presented more severe jaundice and liver injury as well as higher bacterial loads than WT mice but milder pulmonary hemorrhaging. Molecular studies showed that leptospirosis-related bleeding coincides with the temporal kinetics of iNOS production, while jaundice and liver injury are probably due to insufficiently controlled bacterial loads in the liver. These results suggested that TLR4 is essential in mediating host leptospiral clearance and, to some extent, is associated with pulmonary and subcutaneous hemorrhage, probably through downstream inflammatory mediators, iNOS in particular. Overall, our murine model using immunocompetent mice might facilitate future studies into the pathogenesis of jaundice and bleeding in leptospirosis. Meanwhile, our study suggests the prospect of combining antibiotics and immunosuppressants in the treatment of severe leptospirosis presenting with pulmonary hemorrhage.