Hyperimmune colostrum alleviates rheumatoid arthritis in a collagen-induced arthritis murine model.

Our aging population and the accompanying decline in immune function is a growing concern that may be addressed by finding natural methods to enhance the immunocompetence of our elderly. Bovine milk and colostrum from cows that have been immunized have been shown to provide additional immunoglobulins and other bioactive molecules that enhance immune function. The purpose of this study was to investigate the ability of hyperimmune bovine colostrum to alleviate the symptoms of rheumatoid arthritis in a murine model. The collagen-induced arthritis DBA/1J murine model was used for this study. Mice were fed colostrum from immunized cows at either 5 or 10 mg/mouse per day or controls for 49 d. The data showed that the colostrum-fed groups had significantly lower total swelling scores and significantly lower collagen-specific antibody (IgG2a), inflammation-associated antibody (total IgG), and the inflammatory cytokines tumor necrosis factor α, IL-2, IL-6, and IFN-γ. The results strongly suggest that colostrum from immunized cows may have anti-inflammatory activity in a mouse model of rheumatoid arthritis.

HPN328, a Trispecific T Cell-activating Protein Construct Targeting DLL3-Expressing Solid Tumors.

Delta-like ligand 3 (DLL3) is expressed in more than 70% of small cell lung cancers (SCLCs) and other neuroendocrine-derived tumor types. SCLC is highly aggressive and limited therapeutic options lead to poor prognosis for patients. HPN328 is a tri-specific T cell activating construct (TriTAC) consisting of three binding domains: a CD3 binder for T cell engagement, an albumin binder for half-life extension, and a DLL3 binder for tumor cell engagement. In vitro assays, rodent models and non-human primates were used to assess the activity of HPN328. HPN328 induces potent dose-dependent killing of DLL3-expressing SCLC cell lines in vitro concomitant with T cell activation and cytokine release. In an NCI-H82 xenograft model with established tumors, HPN328 treatment led to T cell recruitment and anti-tumor activity. In an immunocompetent mouse model expressing a human CD3ε epitope, mice previously treated with HPN328 withstood tumor rechallenge, demonstrating long-term anti-tumor immunity. When repeat doses were administered to cynomolgus monkeys, HPN328 was well tolerated up to 10 mg/kg. Pharmacodynamic changes, such as transient cytokine elevation, were observed, consistent with the expected mechanism of action of T cell engagers. HPN328 exhibited linear pharmacokinetic in the given dose range with a serum half-life of 78 to 187 hours, supporting weekly or less frequent administration of HPN328 in humans. Preclinical and nonclinical characterization suggests that HPN328 is a highly efficacious, safe, and novel therapeutic candidate. A phase 1/2 clinical trial is currently underway testing safety and efficacy in patients with DLL3 expressing malignancies.

Targeting CD70 in cutaneous T-cell lymphoma using an antibody-drug conjugate in patient-derived xenograft models.

CD70 is a member of the tumor necrosis factor receptor superfamily. Emerging data indicate that CD70 may be a suitable target for various malignancies. We investigated the expression of CD70 in cutaneous and systemic T-cell lymphomas and conducted preclinical studies of SGN-CD70A, a CD70-directed antibody-drug conjugate (ADC), using patient-derived xenograft cutaneous T-cell lymphoma (CTCL PDX) models. CD70 expression was examined by immunohistochemical (IHC) stains in 49 diagnostic specimens of T-cell lymphomas. The activities of SGN-CD70A in growth inhibition and apoptosis induction were examined in CTCL cell lines and primary CTCL tumor cells. Using previously established CTCL PDXs, we conducted a dose-finding trial followed by a phase 2-like trial to evaluate the optimal dosing and the efficacy of SGN-CD70A in tumor-bearing PDX animals. The therapeutic efficacy of SGN-CD70A was measured by tumor-associated cell-free DNA (cfDNA) and survival of treated PDXs. We found that CD70 is highly expressed in T-cell lymphomas, especially in CTCL. SGN-CD70A inhibited cell growth and induced apoptosis in CD70-expressing CTCL cell lines and primary tumors cells. Additionally, SGN-CD70A at 100 µg/kg and 300 µg/kg prolonged the survival of PDXs in a dose-dependent manner. Finally, treatment with 3 doses of SGN-CD70A at 300 µg/kg was superior to a single-dose treatment in survival prolongation (median survival: 111 days vs 39 days; P = .017). Most importantly, multiple dosing of SGN-CD70A induced complete eradication of established tumors in PDXs measured by cfDNA. Our results demonstrated marked antitumor activity of SGN-CD70A in CTCL PDXs, providing compelling support for its clinical investigation.

Cutaneous T-Cell Lymphoma PDX Drug Screening Platform Identifies Cooperation between Inhibitions of PI3Kα/δ and HDAC.

Cutaneous T-cell lymphoma is a form of non-Hodgkin lymphoma that manifests initially in the skin and disseminates systemically as the disease progresses. Mycosis fungoides and Sézary syndrome are the most common subtypes of cutaneous T-cell lymphoma. Advanced mycosis fungoides and Sézary syndrome are life threatening with few treatment options. We searched for new agents by high-throughput screening of selected targeted compounds and identified high-value targets, including phosphatidylinositol 3-kinase (PI3K) and cyclin-dependent kinases. To validate these hits from the screen, we developed patient-derived xenograft mouse models that recapitulated the cardinal features of mycosis fungoides and Sézary syndrome and maintained histologic and molecular characteristics of their clinical counterparts. Importantly, we established a blood-based biomarker assay using tumor cell-free DNA to measure systemic tumor burden longitudinally in living mice during drug therapy. A PI3K inhibitor, BKM120, was tested in our patient-derived xenograft model leading to disease attenuation and prolonged survival. Isoform-specific small interfering RNA knockdowns and isoform-selective PI3K inhibitors identified PI3K-δ as required for tumor proliferation. Additional studies showed a synergistic combination of PI3K-α/δ inhibitors with histone deacetylase inhibitors. The strong preclinical efficacy of this potent combination against multiple patient-derived xenograft models makes it an excellent candidate for further clinical development.

Romidepsin Plus Liposomal Doxorubicin Is Safe and Effective in Patients with Relapsed or Refractory T-Cell Lymphoma: Results of a Phase I Dose-Escalation Study.

PURPOSE: The histone deacetylase (HDAC) inhibitor romidepsin and the anthracycline liposomal doxorubicin (LD) have modest single-agent activity in cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL). We investigated the safety and efficacy of the combination of these two agents in CTCL and PTCL. PATIENTS AND METHODS: Using CTCL cell lines and primary CTCL tumor cells, we demonstrated synergistic antitumor activity with romidepsin plus doxorubicin. We then conducted a phase I dose-escalation study of the romidepsin/LD combination in relapsed/refractory CTCL and PTCL. The primary objective was to determine the MTD of romidepsin in combination with LD at 20 mg/m2 i.v., once every 28 days. RESULTS: Eleven patients with CTCL and 12 patients with PTCL were treated. The MTD of romidepsin was determined to be 12 mg/m2. Grade 3/4 hematologic toxicities included thrombocytopenia (17%), anemia (13%), and neutropenia (9%). The most frequent treatment-related nonhematologic adverse events were fatigue (48%), nausea (48%), vomiting (35%), and anorexia (30%). Among 21 evaluable patients, the overall response rate was 70% [1 complete response (CR), 6 partial responses (PR)] in CTCL and 27% (3 CR, 0 PR) in PTCL. Of the patients with CTCL, 8 of 10 had skin response, including 6 patients (60%) achieving skin involvement less than 10% of their body surface area at time of best response. CONCLUSIONS: Romidepsin plus LD demonstrated an acceptable safety profile and promising clinical efficacy with deep skin responses in relapsed/refractory CTCL. Thus, this combination could be considered as a bridge to skin-directed treatment or allogeneic hematopoietic cell transplantation in patients with aggressive CTCL.

Folate deficiency affects dendritic cell function and subsequent T helper cell differentiation.

Insufficient folate status may be related to the increasing prevalence of immune- or inflammation-related chronic diseases. To investigate the effects of folate on immune regulation, we examined the impact of folate deficiency (FD) on dendritic cell (DC) maturation and function and, thus, T helper (Th) cells differentiation. First, bone marrow-derived DCs (BMDCs) were generated from BALB/c mice bone marrow cells cultured in folate-containing (F-BMDCs) or folate-deficient (FD-BMDCs) medium. FD-BMDC displayed more immature phenotype including reduced levels of major histocompatibility complex class II (MHC II), co-stimulatory molecules and characteristic of higher endocytic activity. FD-BMDC produced less IL-12p70 and proinflammatory cytokines in response to lipopolysaccharide. This aberrant DC maturation due to FD resulted in reduced BMDC-induced Th cell activity and lower IL-2, IFNγ, IL-13 and IL-10 productions. Further in vivo study confirmed significantly lower IFNγ and IL-10 productions by T cells and showed higher splenic naïve Th and lower memory T, effector T and regulatory T cell (Treg) percentages in mice fed with the FD diet for 13 weeks. To investigate the role of DCs on T cell activity, splenic DCs (spDC) from FD mice were cocultured with Th cells. The FD spDC had lower MHC II and CD80 expressions and subsequently impaired DC-induced Th differentiation, shown as decreased cytokine productions. This study demonstrated that folate deficiency impaired DC functions and, thus, Th differentiation and responses, suggesting that folate plays a crucial role in maintaining Th cells homeostasis.

Ethanol Extract of Perilla frutescens Suppresses Allergen-Specific Th2 Responses and Alleviates Airway Inflammation and Hyperreactivity in Ovalbumin-Sensitized Murine Model of Asthma.

This study was to investigate the effects of different fractions of Perilla frutescens (Pf) leaves extracted by water or ethanol on asthma. BALB/c mice sensitized intraperitoneally and challenged with ovalbumin (OVA) were divided into six groups. Each group of mice was tube-feeding with 0 (control), 80 µg (PfWL), or 320 µg (PfWH) water extracts or 80 µg (PfEL) or 320 µg (PfEH) ethanol extracts of perilla leaves daily for 3 weeks. A negative control group (PBS) was neither sensitized nor treated with Pf. The effects of perilla leave extracts on allergic immune response were evaluated. The results showed that OVA-specific IL-5 and IL-13 secretions from OVA-stimulated splenocytes were significantly suppressed in the ethanol extract groups PfEL and PfEH. Serum level of anti-OVA IgE tended to be lower in the PfEH group. The inflammatory mediators, such as eotaxin and histamine, and total cells, particularly eosinophils in bronchoalveolar lavage fluid (BALF), were also decreased in the PfEL and the PfEH groups. Therefore, the PfEL and the PfEH groups had significantly lower methacholine-induced hyperresponsiveness (AHR). In conclusion, ethanol extracts, rather than water extract, of perilla leaves could significantly suppress Th2 responses and airway inflammation in allergic murine model of asthma.

Cellular internalization of quantum dots.

Cell-penetrating peptides (CPPs) can facilitate uptake of quantum dots (QDs) for a variety of basic and applied sciences. Here we describe a method that utilizes simple noncovalent interactions to complex QDs and CPPs. We further describe methods to study uptake mechanisms of the QD/CPP complex. The inhibitor study coupled with the RNA interference (RNAi) technique provides a comprehensive approach to elucidate cellular entry of the QD/CPP complex.

Cytotoxicity in the age of nano: the role of fourth period transition metal oxide nanoparticle physicochemical properties.

A clear understanding of physicochemical factors governing nanoparticle toxicity is still in its infancy. We used a systematic approach to delineate physicochemical properties of nanoparticles that govern cytotoxicity. The cytotoxicity of fourth period metal oxide nanoparticles (NPs): TiO2, Cr2O3, Mn2O3, Fe2O3, NiO, CuO, and ZnO increases with the atomic number of the transition metal oxide. This trend was not cell-type specific, as observed in non-transformed human lung cells (BEAS-2B) and human bronchoalveolar carcinoma-derived cells (A549). Addition of NPs to the cell culture medium did not significantly alter pH. Physiochemical properties were assessed to discover the determinants of cytotoxicity: (1) point-of-zero charge (PZC) (i.e., isoelectric point) described the surface charge of NPs in cytosolic and lysosomal compartments; (2) relative number of available binding sites on the NP surface quantified by X-ray photoelectron spectroscopy was used to estimate the probability of biomolecular interactions on the particle surface; (3) band-gap energy measurements to predict electron abstraction from NPs which might lead to oxidative stress and subsequent cell death; and (4) ion dissolution. Our results indicate that cytotoxicity is a function of particle surface charge, the relative number of available surface binding sites, and metal ion dissolution from NPs. These findings provide a physicochemical basis for both risk assessment and the design of safer nanomaterials.

Toxicity of Transition Metal Oxide Nanoparticles: Recent Insights from in vitro Studies.

Nanotechnology has evolved to play a prominent role in our economy. Increased use of nanomaterials poses potential human health risk. It is therefore critical to understand the nature and origin of the toxicity imposed by nanomaterials (nanotoxicity). In this article we review the toxicity of the transition metal oxides in the 4th period that are widely used in industry and biotechnology. Nanoparticle toxicity is compellingly related to oxidative stress and alteration of calcium homeostasis, gene expression, pro-inflammatory responses, and cellular signaling events. The precise physicochemical properties that dictate the toxicity of nanoparticles have yet to be defined, but may include element-specific surface catalytic activity (e.g., metallic, semiconducting properties), nanoparticle uptake, or nanoparticle dissolution. These in vitro studies substantially advance our understanding in mechanisms of toxicity, which may lead to safer design of nanomaterials.