Tacrolimus and cyclosporine A inhibit allostimulatory capacity and cytokine production of human myeloid dendritic cells.

Myeloid dendritic cells (DCs) are pivotal in the recognition of alloantigens and, therefore, in the induction of allograft rejection. Induction of alloreactive T cell proliferation by myeloid DCs depends on the maturation of DCs, the expression of costimulatory molecules, and the cytokine environment. This study investigated the effects of tacrolimus and cyclosporine A (CsA) on DC maturation and allostimulatory capacity. Myeloid DCs were propagated from normal blood monocytes with interleukin (IL) 4 and GM-CSF for 7 days in the presence or absence of tacrolimus (FK506; 10 nM) or CsA (1 microg/mL). Exposure of DCs during maturation to tacrolimus or CsA resulted in no significant change in the expression of DC phenotypic markers, including CD80, CD86, and HLA Class I and II antigens determined by flow cytometry. T cell proliferation in one-way, mixed-leukocyte reaction experiments revealed a decreased allostimulatory capacity of DCs that matured in the presence of tacrolimus or CsA compared with untreated controls (P<0.02). Production of inflammatory cytokines, tumor necrosis factor alpha (P<0.04) and IL-12 (P<0.04) in response to lipopolysaccharide (1 microg/mL) or staphylococcal enterotoxin B (1 microg/mL) induction was significantly reduced in DCs exposed to tacrolimus or CsA during maturation. In contrast, production of the immuninhibitory cytokine IL-10 was not decreased in tacrolimus- or CsA-treated DCs. These results suggest that tacrolimus and CsA inhibit the allostimulatory capacity of in vitro-generated myeloid DCs without significant effects on DC phenotypic maturation. Decreased production of IL-12 and tumor necrosis factor alpha, but not of IL-10, is likely to contribute to the impaired accessory-cell function of tacrolimus- and CsA-treated DCs. Thus, tacrolimus and CsA can inhibit recognition of alloantigens by decreasing the accessory-cell capacity of monocyte-derived myeloid DCs.     

Reduced Alloreactive T-Cell Activation After Alcohol Intake is Due to Impaired Monocyte Accessory Cell Function and Correlates With Elevated IL-10, IL-13, and Decreased IFNγ Levels

BACKGROUND: Immunosuppression associated with chronic alcohol use is characterized by reduced antigen-specific T-cell response and impaired delayed type hypersensitivity. Increasing evidence suggests in chronic alcohol consumption models that reduced antigen-specific T-cell proliferation is due to insufficient accessory cell function. Accessory cell function, a critical step in recognition of viral antigens, is reduced in chronic hepatitis C. The severity of hepatitis C is increased by alcohol consumption. Thus, we investigated the effects of alcohol consumption on accessory cell activity of monocytes in supporting alloreactive T-cell proliferation. METHODS: Alloreactive T-cell proliferation was evaluated in a one-way mixed lymphocyte reaction (MLR). Mononuclear cells were isolated by Ficoll density gradient and monocytes by adherence. Alcohol (0.8 g/kg body weight, an equivalent of approximately three drinks) was given to nonalcohol-consuming individuals and blood samples were collected before, 4 hr, or 18 hr after alcohol consumption. Alcohol in vitro was administered at concentrations of 25-100 mM. RESULTS: T-cell proliferation in MLR was significantly reduced in the presence of physiologically relevant concentrations of alcohol in vitro (25-100 mM ethanol) (p < 0.05). In vivo alcohol consumption also depressed proliferation in the MLR when stimulator cells were obtained 4 hr after alcohol consumption. MLR was not decreased, however, in the presence of alcohol-exposed responder cells and normal stimulator cells, suggesting that the accessory cell population and not T cells are affected by alcohol. Decreased accessory cell function was further evidenced by reduced superantigen-induced (SEB) but not mitogen-induced (PHA) T-cell proliferation in samples obtained 18 hr after alcohol intake (35% reduction). Reduced accessory cell function was not due to changes in surface expression of monocyte costimulatory molecules (HLA class I, HLA-DR, CD80, CD86, CD40). We found reduced IFNgamma, elevated IL-10, and unchanged IL-4 levels during T-cell proliferation in samples obtained 18 hr after alcohol consumption. Acute alcohol treatment resulted in increased IL-13 in the MLR. CONCLUSION: These data suggest that even on one occasion moderate alcohol intake can reduce allostimulatory T-cell activation via decreasing accessory cell function. Increased IL-10 and IL-13 plus the reduced IFNgamma production after acute alcohol use are likely to contribute to both the reduced T-cell proliferation and monocyte accessory cell function. These accessory cell mediated defects in T-cell activation may result in impaired antiviral and antitumor immunity after moderate acute alcohol use.     

Modeling trajectories of regional volume loss in progressive supranuclear palsy

Progressive supranuclear palsy is a neurodegenerative disease with progressive brain atrophy over time. It is unknown which specific brain regions decline over time, whether regional volume loss occurs in a linear fashion, and whether regional atrophy correlates with clinical decline over time in progressive supranuclear palsy. Twenty‐eight subjects meeting probable progressive supranuclear palsy criteria were prospectively recruited and completed 96 MRI scans over 2 years. Mixed‐effect models were utilized to determine which regions had significant atrophy over time and whether decline was linear or nonlinear. We assessed 13 regions across the brain, as well as whole‐brain and ventricular volume. Regional trajectories were also correlated with change in clinical measures of executive function and gait and ocular motor impairment. A linear decline was observed in all frontal and temporal regions, the superior parietal lobe, the thalamus, the caudate nuclei, and the midbrain, as well as in the whole brain. Ventricular expansion was also linear. Nonlinear decline was observed for the caudal middle frontal lobe and globus pallidus. Rates of change in the superior frontal lobe, thalamus, and midbrain were beyond those expected in normal aging. Decline in frontal lobe volume and the midbrain area correlated best to decline in clinical measures. In progressive supranuclear palsy, atrophy is occurring in multiple brain regions, particularly in those that have previously been implicated in the disease. Decline is mainly linear but can be nonlinear for some regions. The frontal lobe and midbrain seem to be playing the most significant roles in the progressive worsening of clinical signs in progressive supranuclear palsy. © 2013 Movement Disorder Society     

Inhibition Controls for Qualitative Real-Time PCR Assays: Are They Necessary for All Specimen Matrices?

A retrospective analysis of 386,706 specimens representing a variety of matrix types used in qualitative real-time PCR assays determined the overall inhibition rate to be 0.87% when the inhibition control was added preextraction to 5,613 specimens and 0.01% when the inhibition control was added postextraction but preamplification in 381,093 specimens. Inhibition rates of ≤1% were found for all specimen matrix types except urine and formalin-fixed, paraffin-embedded tissue.     

Predictive biomarkers in colorectal cancer: usage, validation, and design in clinical trials

As cancer treatment development has shifted its attention to targeted therapies, it is becoming increasingly important to provide tools for selecting the right treatment for an individual patient to achieve optimal clinical benefit. Biomarkers, identified and studied in the process of understanding the nature of the disease at the molecular pathogenesis level, have been increasingly recognized as a critical aspect in more accurate diagnosis, prognosis assessment, and therapeutic targeting. Predictive biomarkers, which can aid treatment decisions, require extensive data for validation. In this article, we discuss the definition, clinical usages, and more extensively the clinical trial designs for the validation of predictive biomarkers. Predictive biomarker validation methods can be broadly grouped into retrospective and prospective designs. Retrospective validation utilizes data from previously conducted prospective randomized controlled trials. Prospective designs include enrichment designs, treatment-by-marker interaction designs, marker-based strategy designs, and adaptive designs. We discuss each design with examples and provide comparisons of the advantages and disadvantages among the different designs. We conclude that the combination of scientific, clinical, statistical, ethical, and practical considerations provides guidance for the choice of the clinical trial design for validation of each proposed predictive biomarker.     

Phase I trial of sorafenib in combination with gefitinib in patients with refractory or recurrent non-small cell lung cancer.

PURPOSE: To evaluate the combination of sorafenib and gefitinib in patients with advanced non-small cell lung cancer. EXPERIMENTAL DESIGN: In this dose-escalation trial, patients received oral sorafenib (200-400 mg) twice daily with gefitinib (250 mg orally) once daily to identify the recommended dose for phase II trials (RDP; part A). The pharmacokinetics of the RDP were characterized further in additional patients (part B) receiving single-agent gefitinib or sorafenib for 21 days followed by a 7-day washout with crossover to the other agent for an additional 21 days. Patients then received the combination of sorafenib plus gefitinib in 28-day cycles. Safety, pharmacokinetics, and antitumor efficacy were evaluated. Potential drug-drug interactions and the relationship between pharmacokinetics and toxicity were also assessed. RESULTS: Thirty-one patients were treated (n=12, part A; n=19, part B). Most adverse events were grade 1/2. The most frequent grade 3/4 events included diarrhea and elevated alanine aminotransferase (both 9.7%). One dose-limiting toxicity occurred (part A: elevated alanine aminotransferase at 400 mg twice daily). Gefitinib had no effect on sorafenib pharmacokinetics. However, gefitinib C(max) (26%) and area under the curve (38%) were reduced by concomitant sorafenib. One patient had a partial response; 20 (65%; n=8, part A; n=12, part B) had stable disease >or=4 months. The RDP was sorafenib 400 mg twice daily with gefitinib 250 mg once daily. CONCLUSIONS: Sorafenib combined with gefitinib is well tolerated, with promising efficacy in patients with advanced non-small cell lung cancer. Studies to further investigate the significance of the reduction in gefitinib exposure by sorafenib are warranted.