APOLLO: A phase I study of adaptive memory natural killer (NK) cells in recurrent ovarian cancer

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Background: Human cytomegalovirus (CMV) infection induces a subset of long-lived CD57+NKG2C+ adaptive NK cells that exhibit enhanced antibody-dependent cellular cytotoxicity and resistance to tumor-suppressive mechanisms. We developed a 7-day culture process using a GSK3 inhibitor and IL-15 to manufacture modulated adaptive NK cells (FATE-NK100) from CMV+ haploidentical donors for adoptive transfer. The phase I Apollo trial tests the maximum tolerated dose/maximum feasible dose (MTD/MFD) of FATE-NK100 administered intraperitoneally (IP) to treat platinum-sensitive or -resistant recurrent ovarian, fallopian tube, and primary peritoneal cancer. Methods: FATE-NK100 via IP port was tested using 3 dose cohorts ([DC]; 1 × 107 cells/kg; >1 × 107 cells/kg to ≤3 × 107 cells/kg; or >3 × 107 to ≤10 × 107 cells/kg) after lympho-conditioning with fludarabine 25 mg/m2 IV and cyclophosphamide 300 mg/m2 IV on days −6 and −5. After FATE-NK100 infusion on day 0, rhIL-2 at 6 million IU was given IP 3 times a week for 6 doses for in vivo NK activation. IP fluid and peripheral blood were collected regularly until response assessment (day 28). Patients with stable disease or better were eligible for retreatment. Pre- and post-treatment tumor biopsies were collected. Results: Nine patients were treated with no dose-limiting toxicities (DLTs) to date. Retreatment based on clinical benefit was performed on 3 patients (33%), 2 following stable disease (DC 2) and 1 with partial remission (48% tumor reduction, DC 3). IP samples were collected for PK and functional analysis. FATE-NK100 product was detected by flow cytometry in 5 of 6 patients with evaluable samples (range 4.8%–91.2% donor NK cells at day +5-7). Retreatment samples were available in 1 patient, where FATE-NK100 persisted to day +21, demonstrating that repeated IP dosing did not accelerate clearance of the donor NK cells. In that same patient, measurement of NK cell CD107a degranulation or IFNg production in response to K562 targets demonstrated sustained enhanced in vivo function of FATE-NK100 compared to endogenous patient NK cells (e.g. at Day +12 CD107a+ NK were 39.0% vs. 22.5% cycle 1, and 40.3% vs. 18.2% retreatment cycle 2, and IFNg+ NK were 12.3% vs. 5.9% cycle 1, and 2.4% vs. 0.2% retreatment cycle 2). Conclusions: IP delivery of FATE-NK100 is safe, with clinical benefit in 3/9 patients treated. The allogeneic product cells persist and have enhanced function compared to patient NK cells for up to 21 days, even after retreatment. This phase I study in recurrent/refractory ovarian cancer shows promise for IP NK cell delivery. Clinical trial information: NCT00652899.

Activation of human macrophages by the endogenous toll-like receptor 4 ligand high molecular weight hyaluronan (101.20)

Rheumatoid arthritis [RA] is caused in part by cytokines secreted by classically activated synovial macrophages. We reported that IFNγ, typically produced by CD4 T cells within synovitis, primes macrophages for activation by high molecular weight hyaluronan [HMW-HA], a major component of joint synovial fluid. HMW-HA is a ligand for both toll-like receptor 4 [TLR4] and CD44. The purpose of this study was to compare the molecular mechanism of HMW-HA (endogenous TLR ligand) versus LPS (exogenous TLR ligand) induced macrophage activation. Transcriptome bioprofiles were determined by cDNA arrays, and the roles of CD44 and TLR4 were determined using blocking antibodies and cytokine measurement by Milliplex®. Significant differences in gene expression profiles were revealed when comparing IFNγ priming versus mock priming under both LPS and HMW-HA activating conditions, although nearly identical gene expression profiles were observed when comparing HMW-HA to LPS stimulation under both mock and IFNγ priming conditions. Blockade of CD44 enhanced inflammatory cytokine secretion while blockade of TLR4 inhibited inflammatory cytokine secretion in response to either HMW-HA or LPS. HMW-HA provides the stimulus required for classical macrophage activation when cells are primed with IFNγ in a response that is essentially identical to the LPS response. Type 1 T cells in proximity to endogenous TLR ligands may provide sufficient signals to initiate classical macrophage activation in RA.

Reduction of HIV-1 innate immune activation by protease inhibitors (154.15)

HIV-1-associated innate immune activation is caused by viral replication and/or microbial substances that leak from the gut lumen into the circulation (microbial translocation). Consequences of the ensuing HIV-1-associated inflammation range from neurocognitive impairment to cardiovascular disease where macrophages play a central role. HIV-1 therapy is evaluated based on suppression of viremia and restoration of CD4 T cells, while the effects of therapy on innate immune activation are rarely considered. The current study assessed the effects of protease inhibitors on macrophage activation ex vivo and in vivo. Nelfinavir [NFV] and tipranavir [TPV] inhibited LPS activation of human macrophages ex vivo as measured by reduced secretion of LPS-binding protein soluble CD14 [sCD14] and pro-inflammatory cytokines IL-6 and TNF. Cytokine secretion was inhibited prior to transcription by modulation of toll-like receptor signaling pathways. In vivo, NFV-treated HIV-1-infected patients presented with significantly reduced monocyte/macrophage activation as measured by a greater reduction in sCD14 plasma levels compared to those treated with indinavir or ritonavir. These data suggest that anti-inflammatory effects of NFV or TPV may augment efficacy of HIV-1 treatment by targeting HIV-1-assocated innate immune activation. Delineation of cellular targets of NFV or TPV will lead to novel approaches to suppress innate immune activation in HIV-1, other infectious diseases or autoimmunity.

Immunoregulation of dendritic cells by IL-10 is mediated through suppression of the PI3K/Akt pathway and of IkappaB kinase activity

Interleukin-10 (IL-10) has potent immunoregulatory effects on the maturation and the antigen-presenting cell (APC) function of dendritic cells (DCs). The molecular basis underlying these effects in DCs, however, is ill defined. It is well established that the transcription factor NF-kappaB is a key regulator of DC development, maturation, and APC function. This study was initiated to determine the effects of IL-10 on the NF-kappaB signaling pathway in immature DCs. IL-10 pretreatment of myeloid DCs cultured from bone marrow resulted in reduced DNA binding and nuclear translocation of NF-kappaB after anti-CD40 antibody or lipopolysaccharide (LPS) stimulation. Furthermore, inhibited NF-kappaB activation was characterized by reduced degradation, phosphorylation, or both of IkappaBalpha and IkappaBepsilon but not IkappaBbeta and by reduced phosphorylation of Ser536, located in the trans-activation domain of p65. Notably, IL-10-mediated inhibition of NF-kappaB coincided with suppressed IkappaB kinase (IKK) activity in vitro. Furthermore, IL-10 blocked inducible Akt phosphorylation, and inhibitors of phosphatidylinositol 3-kinase (PI3K) effectively suppressed the activation of Akt, IKK, and NF-kappaB. These findings demonstrate that IL-10 targets IKK activation in immature DCs and that suppressing the PI3K pathway in part mediates blockade of the pathway.

NF-kappa B hyperactivation has differential effects on the APC function of nonobese diabetic mouse macrophages

Type 1 diabetes is characterized by a chronic inflammatory response resulting in the selective destruction of the insulin-producing beta cells. We have previously demonstrated that dendritic cells (DCs) prepared from nonobese diabetic (NOD) mice, a model for spontaneous type 1 diabetes, exhibit hyperactivation of NF-kappaB resulting in an increased capacity to secrete proinflammatory cytokines and stimulate T cells compared with DCs of nondiabetic strains of mice. In the current study, the activational status of NF-kappaB and its role in regulating the APC function of macrophages (Mphi) prepared from NOD, nonobese resistant (NOR), and BALB/c mice was investigated. Independent of the stimulus, splenic and bone marrow-derived Mphi prepared from NOD mice exhibited increased NF-kappaB activation relative to NOR and BALB/c Mphi. This hyperactivation was detected for different NF-kappaB complexes and correlated with increased IkappaBalpha degradation. Furthermore, increased NF-kappaB activation resulted in an enhanced capacity of NOD vs NOR or BALB/c Mphi to secrete IL-12(p70), TNF-alpha, and IL-1alpha, which was inhibited upon infection with an adenoviral recombinant encoding a modified form of IkappaBalpha. In contrast, elevated NF-kappaB activation had no significant effect on the capacity of NOD Mphi to stimulate CD4(+) or CD8(+) T cells in an Ag-specific manner. These results demonstrate that in addition to NOD DCs, NOD Mphi exhibit hyperactivation of NF-kappaB, which correlates with an increased ability to mediate a proinflammatory response. Furthermore, NF-kappaB influences Mphi APC function by regulating cytokine secretion but not T cell stimulation.

[Characterization of the cercaria of Bucephalus polymorphus Baer, 1827 (Trematoda, Bucephalidae): chetotaxy and excretory system]

We describe the excretory system and the chetotaxy of the cercaria of Bucephalus polymorphus Baer, 1827 which develops in Dreissena polymorpha (Lamellibranch, Dreissenidae) in South-East of France. We compare our observations with those realised in Poland and we discuss about the differences observed.