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Species-specific antibodies (Ab) for the measurement of immunoglobulins (Ig) are valuable tools for determining the humoral immune status of threatened and endangered wildlife species such as dugongs. However, no studies have reported antibody reagents against dugong immunoglobulin. The object of this study was to develop an Ab with specificity for dugong IgG and apply this tool to survey total IgG levels in plasma samples from a live wild population of dugongs in southern Queensland, Australia. Dugong IgG was isolated from plasma by protein A/G column chromatography and a polyclonal antiserum was successfully raised against the dugong IgG through immunization of mice. The anti-dugong antiserum was reactive with dugong serum but not immunoglobulin from other species such as rats and humans. When tested against a panel of dugong plasma samples, relative IgG levels from dugongs (n = 116) showed biologically relevant relationships with pregnancy status and a principal component of Body Mass Index (BMI)/globulin/fecal glucocorticosteroid (chronic stress) levels combined, which together accounted for 9.2% of the variation in total Ig levels. Together these data suggest that dugongs show variation in total IgG and that this correlates with some physiological parameters of dugong health., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Monocytosis is considered a poor prognostic factor for many cancers, including B cell lymphomas. The mechanisms by which different monocyte subsets support the growth of lymphoma is poorly understood. Using a pre-clinical mouse model of B cell non-Hodgkin's lymphoma (B-NHL), we investigated the impact of tumor progression on circulating monocyte levels, subset distribution and their activity, with a focus on immune suppression. B-NHL development corresponded with significant expansion initially of classical (Ly6Chi) and non-classical (Ly6Clo) monocytes, with accumulation and eventual predominance of Ly6Clo cells. The lymphoma environment promoted the conversion, preferential survival and immune suppressive activity of Ly6Clo monocytes. Ly6Clo monocytes expressed higher levels of immunosuppressive genes including PD-L1/2, Arg1, IDO1 and CD163, compared to Ly6Chi monocytes. Both monocyte subsets suppressed CD8 T cell proliferation and IFN-γ production in vitro , but via different mechanisms. Ly6Chi monocyte suppression was contact dependent, while Ly6Clo monocytes suppressed via soluble mediators, including IDO and arginase. Ly6Clo monocytes could be selectively depleted in tumor-bearing hosts by liposomal doxorubicin treatment, further enhanced by co-administration of anti-4-1BB monoclonal antibody. This treatment led to a reduction in tumor growth, but failed to improve overall survival. Analogous immunosuppressive monocytes were observed in peripheral blood of diffuse large B cell lymphoma patients and actively suppressed human CD8 T cell proliferation. This study highlights a potential immune evasion strategy deployed by B cell lymphoma involving accumulation of circulating non-classical monocytes with immunosuppressive activity.

Importance: Type 2 diabetes (T2D) is increasingly common in young individuals. Primary prevention and screening among children and adolescents who are at substantial risk for T2D are recommended, but implementation of T2D screening practices in the pediatric primary care setting is uncommon., Objective: To determine the feasibility and effectiveness of a computerized clinical decision support system to identify pediatric patients at high risk for T2D and to coordinate screening for and diagnosis of prediabetes and T2D., Design, Setting, and Participants: This cluster-randomized clinical trial included patients from 4 primary care pediatric clinics. Two clinics were randomized to the computerized clinical decision support intervention, aimed at physicians, and 2 were randomized to the control condition. Patients of interest included children, adolescents, and young adults 10 years or older. Data were collected from January 1, 2013, through December 1, 2016., Interventions: Comparison of physician screening and follow-up practices after adding a T2D module to an existing computer decision support system., Main Outcomes and Measures: Electronic medical record (EMR) data from patients 10 years or older were reviewed to determine the rates at which pediatric patients were identified as having a body mass index (BMI) at or above the 85th percentile and 2 or more risk factors for T2D and underwent screening for T2D., Results: Medical records were reviewed for 1369 eligible children (712 boys [52.0%] and 657 girls [48.0%]; median [interquartile range] age, 12.9 [11.2-15.3]), of whom 684 were randomized to the control group and 685 to the intervention group. Of these, 663 (48.4%) had a BMI at or above the 85th percentile. Five hundred sixty-five patients (41.3%) met T2D screening criteria, with no difference between control and intervention sites. The T2D module led to a significant increase in the percentage of patients undergoing screening for T2D (89 of 283 [31.4%] vs 26 of 282 [9.2%]; adjusted odds ratio, 4.6; 95% CI, 1.5-14.7) and a greater proportion attending a scheduled follow-up appointment (45 of 153 [29.4%] vs 38 of 201 [18.9%]; adjusted odds ratio, 1.8; 95% CI, 1.5-2.2)., Conclusions and Relevance: Use of a computerized clinical decision support system to automate the identification and screening of pediatric patients at high risk for T2D can help overcome barriers to the screening process. The support system significantly increased screening among patients who met the American Diabetes Association criteria and adherence to follow-up appointments with primary care clinicians., Trial Registration: clinicaltrials.gov Identifier: NCT01814787.

Combinations of mAbs that target various components of T-cell activation/inhibition may work synergistically to improve antitumor immunity against cancer. In this study, we investigated the therapeutic potential of combining an anticancer vaccination strategy with antibodies targeting an immune stimulatory (4-1BB) and immune inhibitory (PD-1) receptor, in a preclinical model of spontaneously arising c-Myc-driven B-cell lymphoma. In Eμ-myc transgenic mice, we reveal that 4-1BB agonistic mAb treatment alone was sufficient to drive antitumor immunity and prevent disease progression in 70% of mice. When combined with an α-GalCer-loaded, irradiated tumor cell vaccine, 4-1BB mAb treatment led to increased expansion of effector CD8 T-cell populations and protection of long-term surviving mice against tumor rechallenge. Unexpectedly, PD-1 blockade did not provide therapeutic benefit. The T-cell-promoting effects and antitumor activity of 4-1BB mAb were diminished when used simultaneously with a PD-1-blocking mAb. This was associated with a rapid and dramatic reduction in effector CD8 + T-cell subsets in the presence of PD-1 blockade. These findings reveal that supporting T-cell activation therapeutically is effective for controlling B-cell lymphomas; however, caution is required when combining antibody-mediated modulation of both costimulatory and coinhibitory T-cell receptors. Cancer Immunol Res; 5(3); 191-7. ©2017 AACR ., (©2017 American Association for Cancer Research.)

Immunomodulatory therapies can effectively control haematological malignancies by promoting antitumour immunity. Previously, we reported transient growth of poorly immunogenic murine non-Hodgkin B-cell lymphomas (B-NHL) by targeting natural killer T (NKT) cells with a therapeutic vaccine approach. Therapeutic efficacy was highly dependent on the ability of the vaccine to provoke rapid interferon-gamma (IFNγ) production from NKT and NK cells. By manipulating the capacity of either host or lymphoma cells to signal through the IFNγ receptor (IFNγR), we investigated whether the therapeutic effect conferred by vaccine-induced IFNγ is a result of immune cell activation, lymphoma IFNγ sensitivity or a combination of both. We demonstrated that antitumour immunity elicited by vaccination requires IFNγ signalling within host cells but not tumour cells. IFNγR-deficient mice failed to mount an effective antitumour immune response following vaccination despite elevated IFNγ levels. With successive exposure to vaccination, lymphomas acquired an increasingly therapy-resistant phenotype and displayed a reduction in major histocompatibility complex I and CD1d surface expression, which is independent of tumour intrinsic IFNγ signalling. Our results suggest that immunotherapy-induced IFNγ production mainly exerts its therapeutic effect via signalling through host cells, rather than directly to tumour cells in B-NHL. This signifies that intact IFNγ signalling within patients' immune compartment rather than tumour cell sensitivity to IFNγ is more critical for successful treatment. Finally, tumour IFNγ signalling alone does not drive acquired tumour resistance to vaccination, implying that additional immunoediting pathways are responsible for tumour immune escape.

It has been more than 7 years since the commercial introduction of highly successful vaccines protecting against high-risk human papillomavirus (HPV) subtypes and the development of cervical cancer. From an immune standpoint, the dependence of cervical cancer on viral infection has meant that HPV proteins can be targeted as strong tumour antigens leading to clearance of the infection and the subsequent protection from cancer. Commercially available vaccines consisting of the L1 capsid protein assembled as virus-like particles (VLPs) induce neutralising antibodies that deny access of the virus to cervical epithelial cells. While greater than 90% efficacy has been demonstrated at the completion of large phase III trials in young women, vaccine developers are now addressing broader issues such as efficacy in boys, longevity of the protection and inducing cross-reactive antibody for oncogenic, non-vaccine HPV strains. For women with existing HPV infection, the prophylactic vaccines provide little protection, and consequently, the need for therapeutic vaccines will continue into the future. Therapeutic vaccines targeting HPVE6 and E7 proteins are actively being pursued with new adjuvants and delivery vectors, combined with an improved knowledge of the tumour microenvironment, showing great promise. This review will focus on recent progress in prophylactic and therapeutic vaccine development and implementation since the publication of end of study data from phase III clinical trials between 2010 and 2012., (Copyright © 2015 John Wiley & Sons, Ltd.)

The skin is a complex immunological niche providing immunity to invading pathogens while simultaneously maintaining tolerance to innocuous environmental antigens. Consistent with this complex response, the skin is resident to both immunosuppressive and effector cell populations whose activities are tightly regulated. While NKT cells can activate immune responses in the skin, this review will highlight studies on UV-induced photodamage, models of NMSCs, transplantation and allergic inflammation where NKT cells appear to have an immunosuppressive role in the skin., (© 2014 Society for Leukocyte Biology.)

We assessed the production of the canonical Th2 cytokine IL-4 by NKT cells directly in vivo using IL-4-substituting strains of reporter mice that provide faithful and sensitive readouts of cytokine production without the confounding effects of in vitro stimulation. Analysis in naïve animals revealed an "innate" phase of IL-4 secretion that did not need to be triggered by administration of a known NKT cell ligand. This secretion was by immature NKT cells spanning Stage 1 of the maturation process in the thymus (CD4(+) CD44(lo) NK1.1(-) cells) and Stage 2 (CD4(+) CD44(hi) NK1.1(-) cells) in the spleen. Like ligand-induced IL-4 production by mature cells, this innate activity was independent of an initial source of IL-4 protein and did not require STAT6 signaling. A more sustained level of innate IL-4 production was observed in animals on a BALB/c background compared with a C57BL/6 background, suggesting a level of genetic regulation that may contribute to the "Th2-prone" phenotype in BALB/c animals. These observations indicate a regulated pattern of IL-4 expression by maturing NKT cells, which may endow these cells with a capacity to influence the development of surrounding cells in the thymus.

Virus-like particles (VLP) are effective vehicles for delivery of heterologous antigen to antigen-presenting cells. However VLP alone are insufficiently stimulatory to generate the signals required to facilitate effective priming of naïve T cells. We show that the VLP derived from rabbit hemorrhagic disease virus can bind the galactose-containing adjuvant α-galactosylceramide to form a composite particle for co-delivery of antigen and adjuvant to the same antigen-presenting cell. Vaccination with VLP and α-galactosylceramide activated splenic iNKT cells to produce IFN-γ and IL-4, led to the generation of antigen-specific T cells that protected prophylactically against subcutaneous tumor challenge, and was more effective at generating anti-tumor immune responses than either component individually. These data demonstrate a novel method for immunopotentiating VLP to increase their efficacy in the generation of anti-tumor responses via the innate ligand recognition properties of calicivirus-derived nanoparticles., (Copyright © 2012 Elsevier B.V. All rights reserved.)

A computer-assisted method for analyzing photoacoustic spectra has been developed. Using this analysis, the relative absorption spectrum and either the chromophore concentration or thermal diffusivity characteristic of a sample can be derived from its photoacoustic spectrum. We have demonstrated the accuracy of the method by analyzing photoacoustic spectra of solution and crystalline-phase bovine cyanide methemoglobin. BASIC and FORTRAN routines used to collect and to analyze photoacoustic spectra are described. Photoacoustic spectroscopy can be used in conjunction with the analytical method presented here to obtain accurate absorption spectra from a variety of solid, opaque, and/or turbid samples.