The ratio of P40 monomer to dimer is an important determinant of IL-12 bioactivity

Genetic Influences in Breast Cancer Drug Resistance

Breast cancer is the most common cancer in adult women aged 20 to 50 years. The therapeutic regimens that are commonly recommended to treat breast cancer are human epidermal growth factor receptor 2 (HER2) targeted therapy, endocrine therapy, and systemic chemotherapy. The selection of pharmacotherapy is based on the characteristics of the tumor and its hormone receptor status, specifically, the presence of HER2, progesterone receptors, and estrogen receptors. Breast cancer pharmacotherapy often gives different results in various populations, which may cause therapeutic failure. Different types of congenital drug resistance in individuals can cause this. Genetic polymorphism is a factor in the occurrence of congenital drug resistance. This review explores the relationship between genetic polymorphisms and resistance to breast cancer therapy. It considers studies published from 2010 to 2020 concerning the relationship of genetic polymorphisms and breast cancer therapy. Several gene polymorphisms are found to be related to longer overall survival, worse relapse-free survival, higher pathological complete response, and increased disease-free survival in breast cancer patients. The presence of these gene polymorphisms can be considered in the treatment of breast cancer in order to shape personalized therapy to yield better results.

Nasal Wash Cytokines during Respiratory Viral Infection in Pediatric Allogeneic Hematopoietic Cell-Transplant Recipients

Allogeneic hematopoietic cell-transplant (alloHCT) recipients are at increased risk of complications from viral respiratory-tract infections (vRTIs). We measured cytokine concentrations in nasal washes (NWs) from pediatric alloHCT recipients to better understand their local response to vRTI. Forty-one immunologic analytes were measured in 70 NWs, collected during and after vRTI, from 15 alloHCT recipients (median age, 11 yr) with 19 episodes of vRTI. These were compared with NW cytokine concentrations from an independent group of otherwise healthy patients. AlloHCT recipients are able to produce a local response to vRTI and produce IFN-α2 and IL-12p40 in significant quantities above an uninfected baseline early in infection. Compared with otherwise healthy comparator-group patients, alloHCT recipients have higher NW concentrations of IL-4 when challenged with vRTI. Further study of these immunologic analytes as well as of type 1 versus type 2 balance in the respiratory mucosa in the context of vRTI during immune reconstitution may be of future research interest in this vulnerable patient population.

SNPs in the interleukin-12 signaling pathway are associated with breast cancer risk in Puerto Rican women

Interleukin-12 (IL-12) is a proinflammatory cytokine that links innate and adaptive immune responses against tumor cells. Single Nucleotide Polymorphisms (SNPs) in IL-12 genes have been associated with cancer risk. However, limited studies have assessed the role of IL-12 in breast cancer (BC) risk comprehensively, and these were done in European and Asian populations. Here, we evaluated the association of the IL-12 signaling pathway and BC risk in Puerto Rican women. A genetic association study was completed with 461 BC cases and 463 non-BC controls. By logistic regression, IL-12 signaling SNPs were associated with an increased BC risk, including rs2243123 (IL12A), rs3761041, rs401502 and rs404733 (IL12RB1), rs7849191 (JAK2), rs280500 (TYK2) and rs4274624 (STAT4). Conversely, other SNPs were associated with reduced BC risk including rs438421 (IL12RB1), rs6693065 (IL12RB2), rs10974947, and rs2274471 (JAK2), rs10168266 and rs925847 (STAT4), and rs2069718 (IFNG). Analyses based in hormone receptors such as estrogen (ER) and progesterone (PR) receptors also revealed protective (for SNPs rs3212227-IL12B; rs3024896 and rs3821236-STAT4) and predisposing (for rs2069705-IFNG SNP) BC associations. Haplotype analysis showed a decreased BC risk for IL12B and STAT4 SNPs, whereas increased risk for IL12RB1 SNPs. This study suggests a role of the IL-12 signaling axis and BC risk. SNPs in this pathway may alter IL-12 induced anti-tumor responses and modulate BC predisposition in a population-specific context. Functional studies will be necessary to confirm these findings, which potentially may benefit IL-12 related immunotherapeutic approaches towards BC.

Genomic, proteomic, and immunologic associations with a durable complete remission of measurable metastatic melanoma induced by a patient-specific dendritic cell vaccine

This report describes efforts to understand the immune mechanism of action that led to a complete response in a patient with progressive, refractory, metastatic melanoma after treatment with a therapeutic vaccine consisting of autologous dendritic cells (DC) loaded with autologous tumor antigens (ATA) derived from cells that were self-renewing in cell culture. Her histocompatibility type proved to be HLA B27 with extensive mutations in the HLA-A locus. Exomic analysis of proliferating tumor cells revealed more than 2800 non-synonymous mutations compared to her leukocytes. Histology of resected tumor lesions showed no evidence of an existing or suppressed immune response. In in vitro mixed cell cultures, DC loaded with ATA induced increased IL-22 expression, and a four-fold increase in CD8 + T lymphocytes. Cryopreserved blood samples obtained at week-0, 1 week before the first of three-weekly vaccine injections, and at week-4, 1 week after the third dose, were analyzed by protein array and compared for 110 different serum markers. At baseline, she had marked elevations of amyloid A, IL-12p40, IL21, IL-22, IL-10, IL-16, GROa, TNF-alpha, IL-3, and IL-2, and a lesser elevation of IL-15. One week after 3 weekly vaccinations she had a further 80% increase in amyloid A, a further 66% increase in IL-22, a 92% decrease in IL12p40, a 45% decrease in TGF-β and 26% decrease in IL-10. The data suggested that by 3 weeks after the first DCV injection, vaccine-induced changes in this particular patient were most consistent with enhanced innate and Th1 immune responses rather than Th2 or Th17.

Effects of Different Components of PM2.5 on the Expression Levels of NF-κB Family Gene mRNA and Inflammatory Molecules in Human Macrophage

Background: Studies have found that exposure to fine particulate matter with sizes below 2.5 µm (PM2.5) might cause inflammation response via the NF-κB pathway. To date, only a few studies have focused on the toxicity of different components of PM2.5. We aimed to explore the effects of PM2.5 with different components on the expression levels of NF-κB family gene mRNA and inflammatory molecules in human macrophages. Methods: Human monocytic cell line THP-1-derived macrophages were exposed to water-soluble (W-PM2.5), fat-soluble (F-PM2.5), and insoluble (I-PM2.5) PM2.5. The cell survival rate was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of inflammatory molecules were determined by enzyme-linked immunosorbent assay (ELISA), and the relative mRNA levels of the NF-κB family gene were determined by real time PCR. Results: PM2.5 could decrease the cell viability. After exposure to W-PM2.5, the levels of interleukins (IL)-1β and IL-12 p70 significantly increased. After exposure to F-PM2.5, the levels of IL-12 p70 significantly increased. The levels of IL-12 p70 and TNF-α after exposure to I-PM2.5 were significantly higher than that in W- and F-PM2.5 treatment groups. The levels of IL-8, C reactive protein (CRP), and cyclooxygenase (COX)-2 increased only after exposure to I-PM2.5. F-PM2.5 increased the mRNA levels of NF-κB genes, especially NF-κB1 and RelA. Conclusions: PM2.5 can decrease the cell survival rate and up-regulate the expression of NF-κB family gene mRNA and inflammatory molecules. The main toxic components of PM2.5 related to inflammatory response in macrophages were the I-PM2.5.

Preoperative Serum IL-12p40 Is a Potential Predictor of Kasai Portoenterostomy Outcome in Infants with Biliary Atresia

The standard-of-care treatment for biliary atresia (BA) is surgical restoration of bile flow by Kasai portoenterostomy. We aimed to study serum interleukin- (IL-) 12p40, a natural antagonist for the proinflammatory IL-12p70, and its relation to surgical outcomes of BA. The study included 75 infants with neonatal cholestasis: BA group (n = 25), non-BA cholestasis group (n = 30), and neglected BA group (n = 20), in addition to thirty healthy neonates serving as controls. IL-12p40 was measured by ELISA in all individuals and a second assessment was performed 3 months postoperatively in the BA group. The surgical outcomes were classified as successful (bilirubin ≤ 2 mg/dl) or failed (bilirubin > 2 mg/dl). IL-12p40 was higher in BA compared to that in the non-BA and control groups (P values were 0.036 and <0.0001, resp.) but comparable to that in the neglected BA group. Preoperative IL-12p40 levels in BA patients were significantly higher in successful Kasai compared with failed Kasai and a cutoff level of 547.47 pg/ml could predict the successful outcome with 87.5% sensitivity and 82.4% specificity. Three-month postoperative IL-12p40 tended to decrease in both the successful and failed groups. In conclusion, preoperative serum IL-12p40 is a potential predictor of Kasai outcome. Serial postoperative measurements may anticipate the failure of an initially successful operation, hence the need for liver transplantation.

Regulation of Interleukin-12 Production in Antigen-Presenting Cells

Interleukin-12 is a heterodimeric cytokine produced primarily by pathogen-activated antigen-presenting cells, particularly macrophages and dendritic cells, during encountering with intracellular microbes. IL-12 plays a key role in the activation of natural killer cells and CD4⁺ T helper cells in both innate and adaptive immune responses against infectious agents and immunosurveillance against endogenous malignancies. However, the potency of IL-12 makes it a target for stringent regulation. Indeed, the temporal, spatial, and quantitative expression of IL-12 during an immune response in a microenvironment contributes critically to the determination of the type, extent, and ultimate resolution of the reaction. Breaching of the delicate control and balance involving IL-12 frequently leads to autoimmune inflammatory disorders and pathogenesis. Thus, a better understanding of the regulatory mechanisms in the production and control of this cytokine is both scientifically significant and clinically beneficial. Here we provide an update on the research that has been conducted on this subject particularly in the last 10 years since the publication of a major thesis of this nature.

Induction of Wnt-inducible signaling protein-1 correlates with invasive breast cancer oncogenesis and reduced type 1 cell-mediated cytotoxic immunity: a retrospective study

Innate and type 1 cell-mediated cytotoxic immunity function as important extracellular control mechanisms that maintain cellular homeostasis. Interleukin-12 (IL12) is an important cytokine that links innate immunity with type 1 cell-mediated cytotoxic immunity. We recently observed in vitro that tumor-derived Wnt-inducible signaling protein-1 (WISP1) exerts paracrine action to suppress IL12 signaling. The objective of this retrospective study was three fold: 1) to determine whether a gene signature associated with type 1 cell-mediated cytotoxic immunity was correlated with overall survival, 2) to determine whether WISP1 expression is increased in invasive breast cancer, and 3) to determine whether a gene signature consistent with inhibition of IL12 signaling correlates with WISP1 expression. Clinical information and mRNA expression for genes associated with anti-tumor immunity were obtained from the invasive breast cancer arm of the Cancer Genome Atlas study. Patient cohorts were identified using hierarchical clustering. The immune signatures associated with the patient cohorts were interpreted using model-based inference of immune polarization. Reverse phase protein array, tissue microarray, and quantitative flow cytometry in breast cancer cell lines were used to validate observed differences in gene expression. We found that type 1 cell-mediated cytotoxic immunity was correlated with increased survival in patients with invasive breast cancer, especially in patients with invasive triple negative breast cancer. Oncogenic transformation in invasive breast cancer was associated with an increase in WISP1. The gene expression signature in invasive breast cancer was consistent with WISP1 as a paracrine inhibitor of type 1 cell-mediated immunity through inhibiting IL12 signaling and promoting type 2 immunity. Moreover, model-based inference helped identify appropriate immune signatures that can be used as design constraints in genetically engineering better pre-clinical models of breast cancer.

Effective anti-tumor immunity is proportional to the number and to the cytotoxic activity of immune cells that enter the tumor microenvironment. Recent advances in cancer immunotherapy stem from increasing the number of tumor-infiltrating immune cells by inhibiting immune checkpoints or adoptive T cell therapy. Here, we used computational methods to identify potential mechanisms present within the tumor microenvironment that limit the efficacy of anti-tumor immunity. Specifically, we found that oncogenic transformation is associated with the induction of tumor-derived biochemical cues, namely Wnt-inducible signaling protein-1, that locally suppress anti-tumor immunity. Moreover, we used model-based inference to demonstrate that a gene signature consistent with effective type 1 cell-mediated cytotoxic immunity is a predictor of overall survival independent of molecular pathology. Interestingly, patients with triple negative breast cancer were more enriched in the cohort associated with type 1 cell-mediated immunity. As this immune gene signature is not present in current genetically engineered mouse models of breast cancer, the results help identify design constraints for engineering better pre-clinical models of breast cancer. Demonstrating efficacy in pre-clinical animal models is a pre-requisite for bringing improved cancer immunotherapies into the clinic.

Comparative multiplex analysis of cytokines, chemokines and growth factors in follicular fluid of normoresponder women undergoing ovum donation with gonadotropin-releasing hormone agonist versus gonadotropin-releasing hormone antagonist protocols

BACKGROUND:

Conflicting results were yielded about the superiority of gonadotropin-releasing hormone agonist (GnRH-a) versus gonadotropin-releasing hormone antagonist (GnRH-ant) protocols used in ovarian stimulation in in vitro fertilization (IVF) set-up. Reports also indicate that any single specific individual marker in follicular fluid collected at the time of oocyte retrieval bears inconclusive value as a predictor of oocyte quality.

AIMS:

Simultaneous analyses of large numbers of cytokines, chemokines and growth factors in ovarian follicular fluid and perifollicular vascularity in both protocols for ovarian stimulation in IVF program to address the above mentioned lacunae.

SETTINGS AND DESIGNS:

Normoresponder women (n = 45) were subjected to either GnRH-a (Group 1; n = 23) or GnRH-ant (Group 2; n = 22) for ovarian stimulation in IVF clinics.

MATERIALS AND METHODS:

The fluid samples of dominant follicles collected at oocyte retrieval from women in Group 1 (GnRH-a; n = 20) and Group 2 (GnRH-ant; n = 16) were used for simultaneous quantitative assays of 48 cytokines. Perifollicular vascularity was assessed by Doppler hemodynamics to assess the ovarian vascular response in all participants in Groups 1 and 2.

RESULTS:

Despite demographic and reproductive parameters studied remained comparable, higher follicular fluid concentration of interleukins, IL-3 (P < 0.01), IL12p70 (P < 0.05) and vascular endothelial growth factor (P < 0.01), P4 (P < 0.05) and pulsatility index (P < 0.04) along with a lower number of oocytes in metaphase II stage (P < 0.03) was observed in Group 2 compared with Group 1. GnRH-a protocol appeared to be superior to GnRH-ant protocol for ovarian stimulation in normoresponder women.

Cerebrospinal fluid IL-12p40, CXCL13 and IL-8 as a combinatorial biomarker of active intrathecal inflammation

Diagnosis and management of the neuroinflammatory diseases of the central nervous system (CNS) are hindered by the lack of reliable biomarkers of active intrathecal inflammation. We hypothesized that measuring several putative inflammatory biomarkers simultaneously will augment specificity and sensitivity of the biomarker to the clinically useful range. Based on our pilot experiment in which we measured 18 inflammatory biomarkers in 10-fold concentrated cerebrospinal fluid (CSF) derived from 16 untreated patients with highly active multiple sclerosis (MS) we selected a combination of three CSF biomarkers, IL-12p40, CXCL13 and IL-8, for further validation.Concentrations of IL-12p40, CXCL13 and IL-8 were determined in a blinded fashion in CSF samples from an initial cohort (n = 72) and a confirmatory cohort (n = 167) of prospectively collected, untreated subjects presenting for a diagnostic work-up of possible neuroimmunological disorder. Diagnostic conclusion was based on a thorough clinical workup, which included laboratory assessment of the blood and CSF, neuroimaging and longitudinal follow-up. Receiver operating characteristic (ROC) curve analysis in conjunction with principal component analysis (PCA), which was used to combine information from all three biomarkers, assessed the diagnostic value of measured biomarkers.Each of the three biomarkers was significantly increased in MS and other inflammatory neurological disease (OIND) in comparison to non-inflammatory neurological disorder patients (NIND) at least in one cohort. However, considering all three biomarkers together improved accuracy of predicting the presence of intrathecal inflammation to the consistently good to excellent range (area under the ROC curve = 0.868-0.924).Future clinical studies will determine if a combinatorial biomarker consisting of CSF IL-12p40, CXCL13 and IL-8 provides utility in determining the presence of active intrathecal inflammation in diagnostically uncertain cases and in therapeutic development and management.

Timescale analysis of rule-based biochemical reaction networks

The flow of information within a cell is governed by a series of protein-protein interactions that can be described as a reaction network. Mathematical models of biochemical reaction networks can be constructed by repetitively applying specific rules that define how reactants interact and what new species are formed on reaction. To aid in understanding the underlying biochemistry, timescale analysis is one method developed to prune the size of the reaction network. In this work, we extend the methods associated with timescale analysis to reaction rules instead of the species contained within the network. To illustrate this approach, we applied timescale analysis to a simple receptor-ligand binding model and a rule-based model of interleukin-12 (IL-12) signaling in naïve CD4+ T cells. The IL-12 signaling pathway includes multiple protein-protein interactions that collectively transmit information; however, the level of mechanistic detail sufficient to capture the observed dynamics has not been justified based on the available data. The analysis correctly predicted that reactions associated with Janus Kinase 2 and Tyrosine Kinase 2 binding to their corresponding receptor exist at a pseudo-equilibrium. By contrast, reactions associated with ligand binding and receptor turnover regulate cellular response to IL-12. An empirical Bayesian approach was used to estimate the uncertainty in the timescales. This approach complements existing rank- and flux-based methods that can be used to interrogate complex reaction networks. Ultimately, timescale analysis of rule-based models is a computational tool that can be used to reveal the biochemical steps that regulate signaling dynamics.

Lys-des[Arg9]-bradykinin alters migration and production of interleukin-12 in monocyte-derived dendritic cells

This study tested the hypothesis that proinflammatory kinin peptides are involved in modulating human dendritic cell (DC) function. Inflammation is accompanied by an increased maturation of DCs and the generation of kinins, particularly Lys-des[Arg(9)]-bradykinin (Lda-BK). We assessed the role of Lda-BK in the activation and migration of human monocyte-derived DCs (hMo-DCs) matured through the use of LPS, TNF-α + IL-1β, or CD40 ligand. Kinin B(1) and B(2) receptor mRNA and protein expression were assessed by confocal microscopy, flow cytometry, and RT-PCR. The effects of Lda-BK on the migration of mature hMo-DCs were assessed in Transwell chambers, whereas the expression of costimulatory molecules and the secretion of IL-12 were assessed by flow cytometry and ELISA, respectively. The expression of the kinin B(1) receptor (B(1)R) was down-regulated during the maturation of hMo-DCs, whereas the expression of B(2)R was unchanged. The B(1)R agonist Lda-BK was not chemotactic for hMo-DCs matured using LPS, TNF-α + IL-1β, or CD40 ligand, but Lda-BK enhanced the secretion of IL-12p70 and inhibited the secretion of IL-12p40 by mature hMo-DCs. However, the exposure of hMo-DCs matured with TNF-α + IL-1β to Lda-BK for 6 hours decreased subsequent migration in response to Lda-BK, the chemokine CCL19, or Lda-BK combined with CCL19. The expression of B(1)R was increased in hMo-DCs from subjects with asthma compared with subjects without asthma, in keeping with a tendency toward increased in vitro migration of asthmatic hMo-DCs in response to Lda-BK. The increased formation of Lda-BK and the enhanced expression of B(1)R as a consequence of inflammation may alter the migration of mature, antigen-laden DCs to regional lymph nodes in response to CCL19, may modulate the secretion of cytokines by these DCs, and may contribute to the accumulation of mature DCs in the lungs of patients with asthma.

A multiscale systems perspective on cancer, immunotherapy, and Interleukin-12

Monoclonal antibodies represent some of the most promising molecular targeted immunotherapies. However, understanding mechanisms by which tumors evade elimination by the immune system of the host presents a significant challenge for developing effective cancer immunotherapies. The interaction of cancer cells with the host is a complex process that is distributed across a variety of time and length scales. The time scales range from the dynamics of protein refolding (i.e., microseconds) to the dynamics of disease progression (i.e., years). The length scales span the farthest reaches of the human body (i.e., meters) down to the range of molecular interactions (i.e., nanometers). Limited ranges of time and length scales are used experimentally to observe and quantify changes in physiology due to cancer. Translating knowledge obtained from the limited scales observed experimentally to predict patient response is an essential prerequisite for the rational design of cancer immunotherapies that improve clinical outcomes. In studying multiscale systems, engineers use systems analysis and design to identify important components in a complex system and to test conceptual understanding of the integrated system behavior using simulation. The objective of this review is to summarize interactions between the tumor and cell-mediated immunity from a multiscale perspective. Interleukin-12 and its role in coordinating antibody-dependent cell-mediated cytotoxicity is used illustrate the different time and length scale that underpin cancer immunoediting. An underlying theme in this review is the potential role that simulation can play in translating knowledge across scales.

Inferring relevant control mechanisms for interleukin-12 signaling in naïve CD4+ T cells

Interleukin-12 (IL-12) is a key cytokine involved in shaping the cell-mediated immunity to intracellular pathogens. IL-12 initiates a cellular response through the IL-12 signaling pathway, a member of the Janus kinase/signal transducer and activator of transcription (JAK/STAT) family of signaling networks. The JAK/STAT pathway includes several regulatory elements; however, the dynamics of these mechanisms are not fully understood. Therefore, the objective of this study was to infer the relative importance of regulatory mechanisms that modulate the activation of STAT4 in naïve CD4(+) T cells. Dynamic changes in protein expression and activity were measured using flow cytometry and these data were used to calibrate a mathematical model of IL-12 signaling. An empirical Bayesian approach was used to infer the relative strengths of the different regulatory mechanisms in the system. The model predicted that IL-12 receptor expression is regulated by a dynamic, autonomous program that was independent of STAT4 activation. In summary, a mathematical model of the canonical IL-12 signaling pathway used in conjunction with a Bayesian framework provided high-confidence predictions of the system-specific control mechanisms from the available experimental observations.

Ex vivo recovery and activation of dysfunctional, anergic, monocyte-derived dendritic cells from patients with operable breast cancer: critical role of IFN-alpha

BACKGROUND

Dendritic cells (DCs) play a crucial role in initiating effective cell-mediated immune responses, but are dysfunctional and anergic in breast cancer. Reversal of this dysfunction and establishment of optimal DC function is a key prerequisite for the induction of effective anti-cancer immune responses.

RESULTS

Peripheral blood DCs (PBDCs) and lymph node DCs (LNDCs) generated in vitro from adherent cultures of peripheral blood monocytes (PBMs) and lymph node monocytes (LNMs), respectively, using the 4 cytokine conditioned medium (CCM) (GM-CSF+IL-4+TNF-alpha+IFN-alpha) or 3 CCM (GM-CSF+IL-4+TNF-alpha) demonstrated a significantly higher degree of recovery and functional capacity in a mixed lymphocyte DC reaction (MLDCR, p < 0.001), expressed significantly higher levels of HLA-DR, CD86, compared with 2 CCM (GM-CSF+IL-4) or medium alone generated DCs from PBMs and LNMs (p < 0.001). The PBDCs generated with 3 CCM or 4 CCM showed a significantly (p < 0.001) enhanced macropinocytotic capability (dextran particles) and induced increased production and secretion of interleukin-12p40 (IL-12p40) in vitro (p < 0.001), compared with PBDCs generated from monocytes using 2 CCM or medium alone. Lipopolysaccharide (LPS) stimulation of PBDCs generated with 4 CCM demonstrated enhanced secretion of IL-6 but not IL-12p70, compared with control DCs unstimulated with LPS (p < 0.001).

CONCLUSION

Dysfunctional and anergic PBDCs and LNDCs from patients with operable breast cancer can be optimally reversed by ex vivo culturing of precursor adherent monocytes using a 4 CCM containing IFN-alpha. Maximal immunophenotypic recovery and functional reactivation of DCs is seen in the presence of IFN-alpha. However, 4 CCM containing IFN-alpha generated-PBDCs, do not produce and secrete IL-12p70 in vitro.

Norepinephrine modulates human dendritic cell activation by altering cytokine release

Norepinephrine (NE) can modulate dendritic cell (DC) activation in animal models, but the response of human DC to NE and other response modifiers is as yet not completely understood. Here we report the effect of NE on the cytokine response of a mixed population of human DC cells to extracellular stimuli. These cells were obtained by differentiating human cord blood CD34+ precursor cells. NE inhibited the lipopolysaccharide (LPS)-stimulated production of interleukin (IL)-23, IL-12 p40, tumor necrosis factor (TNF)-alpha and IL-6 whereas the expression of IL-10 was not significantly affected. Thus, human cord blood-derived DC respond to NE in a manner similar to mouse Langerhans cells (LC). Furthermore, forskolin also inhibited the LPS-induced levels of TNF-alpha, IL-12 p40, IL-23 p19 and IL-6, supporting the hypothesis that the effects of NE are mediated by cAMP. Data from experiments using inhibitors of adrenergic receptors suggest that NE acts through beta-adrenergic receptors. As IL-23 promotes the differentiation of CD4+ T cells required for T(H)1-mediated immunity, we suggest that NE decreases the differentiation of CD4+ T cells needed for T(H)1-mediated contact hypersensitivity and that NE is a candidate regulator of human DC functions in the skin.

A Multi-Scale Model of Dendritic Cell Education and Trafficking in the Lung: Implications for T Cell Polarization

Health Sciences face a significant challenge in translating basic science data into improved understanding of innate and adaptive immunity. To improve understanding of the dynamic role of dendritic cells in the lung, a mathematical model was developed using a physiologically structured framework that explicitly accounts for functional heterogeneity. As sentinels of the immune system, dendritic cells play critical roles in coupling innate to adaptive immunity and produce an important immune regulatory cytokine: IL-12. The term IL-12 actually refers to the net bioactivity of three related proteins; IL12p40, IL12p70, and IL12(p40)2; assembled from two independent gene products: p35 and p40. The model for dendritic cell education and trafficking was created by incorporating five dimensions: chronological time, maturational age, p35 signal, p40 signal, and spatial location. The computational framework was calibrated to and validated against appropriate experimental studies. Using this validated model, I explore the impact of dynamic changes in the lung epithelium of IL-4, IFN-gamma, and PGE2 on the dynamic ability of dendritic cells to polarize T cell subsets. In summary, this multi-scale model provides an essential aid in understanding the impact of a dynamically changing lung microenvironment on the ability of dendritic cells to orchestrate adaptive immunity.