Modulation of the immune system through the use of micro and nano carriers offers opportunities in transplant tolerance, autoimmunity, infectious disease, and cancer. In particular, polymeric, lipid, ...and inorganic materials have been used as carriers of proteins, nucleic acids, and small drug molecules to direct the immune system toward either suppressive or stimulatory states. Current technologies have focused on the use of particulates or scaffolds, the modulation of materials properties, and the delivery of biologics or small drug molecules to achieve a desired response. Discussed are relevant immunology concepts, the types of biomaterial carriers used for immunomodulation highlighting their benefits and drawbacks, the material properties influencing immune responses, and recent examples in the field of transplant tolerance.
This minireview discusses biomaterial carriers used for immunomodulation, the material properties influencing immune responses, and recent examples in the field of transplant tolerance.
Although there is increasing evidence to support the implementation of pharmacogenetics in certain clinical scenarios, the adoption of this approach has been limited. The advent of preemptive and ...inexpensive testing of critical pharmacogenetic variants may overcome barriers to adoption. We describe the design of a customized array built for the personalized‐medicine programs of the University of Florida and Stanford University. We selected key variants for the array using the clinical annotations of the Pharmacogenomics Knowledgebase (PharmGKB), and we included variants in drug metabolism and transporter genes along with other pharmacogenetically important variants.
Clinical Pharmacology & Therapeutics (2012); 92 4, 437–439. doi:10.1038/clpt.2012.125
Functional Defects and the Influence of Age on the Frequency of CD4 + CD25 + T-Cells in Type 1 Diabetes
Todd M. Brusko 1 ,
Clive H. Wasserfall 1 ,
Michael J. Clare-Salzler 1 ,
Desmond A. Schatz 2 and
...Mark A. Atkinson 1
1 Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, Florida
2 Department of Pediatrics, University of Florida, Gainesville, Florida
Address correspondence and reprint requests to Mark A. Atkinson, PhD, Department of Pathology, College of Medicine, University
of Florida, ARB-R3-128, 1600 SW Archer Rd., Gainesville, FL 32610-0275. E-mail: atkinson{at}ufl.edu
Abstract
CD4 + CD25 + T-cells appear to play a crucial role in regulating the immune response. Therefore, we evaluated the peripheral blood frequency
and function of CD4 + CD25 + T-cells in 70 type 1 diabetic patients and 37 healthy individuals. Interestingly, a positive correlation was observed between
increasing age and CD4 + CD25 + T-cell frequency in both subject groups. In contrast to previous studies of nonobese diabetic mice and type 1 diabetic patients,
similar frequencies of CD4 + CD25 + and CD4 + CD25 +Bright T-cells were observed in healthy control subjects and type 1 diabetic patients of similar age. There was no difference between
type 1 diabetic subjects of recent-onset versus those with established disease in terms of their CD4 + CD25 + or CD4 + CD25 +Bright T-cell frequency. However, type 1 diabetic patients were markedly defective in their ability to suppress the proliferation
of autologous effector T-cells in vitro. This type 1 diabetes-associated defect in suppression was associated with reduced
production of interleukin (IL)-2, γ-interferon, and transforming growth factor-β, whereas other cytokines including those
of adaptive and innate immunity (IL-10, IL-1β, IL-6, IL-8, IL-12p70, and tumor necrosis factor-α) were similar in control
subjects and type 1 diabetic patients. These data suggest that age strongly influences the frequency of CD4 + CD25 + T-cells and that function, rather than frequency, may represent the means by which these cells associate with type 1 diabetes
in humans.
APC, allophycocyanin
GM-CSF, granulocyte-macrophage colony-stimulating factor
IFN-γ, γ-interferon
IL, interleukin
PE, phycoerythrin
Teff, CD4+CD25− effector T-cell
TGF, transforming growth factor
TNF, tumor necrosis factor
Treg, CD4+CD25+ regulatory T-cell
Footnotes
Accepted February 9, 2005.
Received October 20, 2004.
DIABETES
Abstract Immunogenomic approaches combined with advances in adjuvant immunology are guiding progress toward rational design of vaccines. Furthermore, drug delivery platforms (e.g., synthetic ...particles) are demonstrating promise for increasing vaccine efficacy. Currently there are scores of known antigenic epitopes and adjuvants, and numerous synthetic delivery systems accessible for formulation of vaccines for various applications. However, the lack of an efficient means to test immune cell responses to the abundant combinations available represents a significant blockade on the development of new vaccines. In order to overcome this barrier, we report fabrication of a new class of microarray consisting of antigen/adjuvant-loadable poly( d , l lactide- co -glycolide) microparticles (PLGA MPs), identified as a promising carrier for immunotherapeutics, which are co-localized with dendritic cells (DCs), key regulators of the immune system and prime targets for vaccines. The intention is to utilize this high-throughput platform to optimize particle-based vaccines designed to target DCs in vivo for immune system-related disorders, such as autoimmune diseases, cancer and infection. Fabrication of DC/MP arrays leverages the use of standard contact printing miniarraying equipment in conjunction with surface modification to achieve co-localization of particles/cells on isolated islands while providing background non-adhesive surfaces to prevent off-island cell migration. We optimized MP overspotting pin diameter, accounting for alignment error, to allow construction of large, high-fidelity arrays. Reproducible, quantitative delivery of as few as 16 ± 2 MPs per spot was demonstrated and two-component MP dosing arrays were constructed, achieving MP delivery which was independent of formulation, with minimal cross-contamination. Furthermore, quantification of spotted, surface-adsorbed MP degradation was demonstrated, potentially useful for optimizing MP release properties. Finally, we demonstrate DC co-localization with PLGA MPs on isolated islands and that DCs do not migrate between islands for up to 24 h. Using this platform, we intend to analyze modulation of DC function by providing multi-parameter combinatorial cues in the form of proteins, peptides and other immuno-modulatory molecules encapsulated in or tethered on MPs. Critically, the miniaturization attained enables high-throughput investigation of rare cell populations by reducing the requirement for cells and reagents by many-fold, facilitating advances in personalized vaccines which target DCs in vivo.
Summary Crohn's disease (CD) is a chronic inflammatory condition of the human gastrointestinal tract whose aetiology remains largely unknown. Dysregulated adaptive immune responses and defective ...innate immunity both contribute to this process. In this study, we demonstrated that the interleukin (IL)-17A+interferon (IFN)-gamma+ and IL-22+IFN-gamma+ T cell subsets accumulated specifically in the inflamed terminal ileum of CD patients. These cells had higher expression of Ki-67 and were active cytokine producers. In addition, their proportions within both the IL-17A-producer and IL-22-producer populations were increased significantly. These data suggest that IL-17A+IFN-gamma+ and IL-22+IFN-gamma+ T cell subsets might represent the pathogenic T helper type 17 (Th17) population in the context of intestinal inflammation for CD patients. In the innate immunity compartment we detected a dramatic alteration of both phenotype and function of the intestinal innate lymphoid cells (ILCs), that play an important role in the maintenance of mucosal homeostasis. In the inflamed gut the frequency of the NKp44-CD117-ILC1s subset was increased significantly, while the frequency of NKp44+ILC3s was reduced. Furthermore, the frequency of human leucocyte antigen D-related (HLA-DR)-expressing-NKp44+ILC3s was also reduced significantly. Interestingly, the decrease in the NKp44+ILC3s population was associated with an increase of pathogenic IL-17A+IFN-gamma+ and IL-22+IFN-gamma+ T cell subsets in the adaptive compartment. This might suggest a potential link between NKp44+ILC3s and the IL-17A+IFN-gamma+ and IL-22+IFN-gamma+ T cell subsets in the terminal ileum of CD patients.
It is highly desirable that immature dendritic cells (DC) used for tolerance induction maintain steady immature state with predominant interleukin (IL)‐10 production. In this study, we attempted to ...develop DC with durable immaturity and other tolerogenic features by using dexamethasone (Dex). We found DC derived from human monocytes in the presence of 10−7 m Dex were negative for CD1a. Compared with control transduced DC (Ctrl‐DC), Dex‐DC expressed lower CD40, CD80 and CD86 but equivalent human leucocyte antigen‐DR. Both immature Dex‐ and Ctrl‐DC did not express CD83. Nevertheless, upon stimulation of lipopolysaccharide (LPS) or CD40 ligand, the expression of CD40, CD80, CD83 and CD86 was upregulated on Ctrl‐DC but not on Dex‐DC. The immaturity of Dex‐DC was durable following Dex removal. Interestingly, Dex‐DC maintained production of large amount of IL‐10 and little IL‐12 five days after Dex removed. Further study indicated that high‐level IL‐10 production by Dex‐DC was associated with high‐level phosphorylation of extracellular signal‐regulated kinase (ERK) as blockade of this enzyme markedly attenuated IL‐10 production. Furthermore, Dex‐DC sustained the capability of high phosphorylation of ERK and IL‐10 production 5 days after Dex removal. In addition, Dex‐DC had significantly lower activity in stimulating T‐cell proliferation. Neutralization of IL‐10, to some extent, promoted DC maturation activated by LPS, as well as T‐cell stimulatory activity of Dex‐DC. The above findings suggest that IL‐10‐producing Dex‐DC with durable immaturity are potentially useful for induction of immune tolerance.
Objective: We conducted a dietary validation study in youth aged 1-11 years by comparing dietary intake of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) as assessed by a parent-completed ...semiquantitative food frequency questionnaire (FFQ) over time to erythrocyte membrane composition of the same fatty acids. Design: The study population included youth aged 1-11 years who were participants in the Diabetes Autoimmunity Study in the Young (DAISY), a longitudinal study in Denver, Colorado that is following a cohort of youth at risk for developing type I diabetes. Four hundred and four children who had erythrocyte membrane fatty acid data matched to an FFQ corresponding to the same time frame for a total of 917 visits (matches) were included. PUFA intake was expressed both as g/day (adjusted for total energy) and as percent of total fat intake. We used mixed models to test the association and calculate the correlation between the erythrocyte membrane estimates and PUFA intake using all records of data for each youth. Results: Intakes of total omega-3 fatty acids (β=0.52, P<0.0001, rho =0.23) and marine PUFAs (Objective: We conducted a dietary validation study in youth aged 1-11 years by comparing dietary intake of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) as assessed by a parent-completed semiquantitative food frequency questionnaire (FFQ) over time to erythrocyte membrane composition of the same fatty acids. Design: The study population included youth aged 1-11 years who were participants in the Diabetes Autoimmunity Study in the Young (DAISY), a longitudinal study in Denver, Colorado that is following a cohort of youth at risk for developing type I diabetes. Four hundred and four children who had erythrocyte membrane fatty acid data matched to an FFQ corresponding to the same time frame for a total of 917 visits (matches) were included. PUFA intake was expressed both as g/day (adjusted for total energy) and as percent of total fat intake. We used mixed models to test the association and calculate the correlation between the erythrocyte membrane estimates and PUFA intake using all records of data for each youth. Results: Intakes of total omega-3 fatty acids (β=0.52, P<0.0001, rho=0.23) and marine PUFAs (β=1.62, P<0.0001, rho=0.42), as a percent of total fat in the diet, were associated with percent of omega-3 and marine PUFAs in the erythrocyte membrane. Intakes of omega-6 PUFAs (β=0.04, P=0.418, rho=0.05) and arachidonic acid (β=0.31, P=0.774, rho=0.01) were not associated. Conclusions: In these young children, an FFQ using parental report provided estimates of average long-term intakes of marine PUFAs that correlated well with their erythrocyte cell membrane fatty acid status.
Abstract While it is well-known that adsorbed proteins on implanted biomaterials modulate inflammatory responses, modulation of dendritic cells (DCs) via adhesion-dependent signaling has only been ...begun to be characterized. In this work, we demonstrate that adhesive substrates elicit differential DC maturation and adaptive immune responses. We find that adhesive substrates support similar levels of DC adhesion and expression of stimulatory and co-stimulatory molecules. Conversely, DC morphology and differential production of pro- and anti-inflammatory cytokines (IL-12p40 and IL-10, respectively) is adhesive substrate-dependent. For example, DCs cultured on collagen and vitronectin substrates generate higher levels of IL-12p40, whereas DCs cultured on albumin and serum-coated tissue culture-treated substrates produce the higher levels of IL-10 compared to other substrates. Additionally, our results suggest substrate-dependent trends in DC-mediated allogeneic CD4+ T-cell proliferation and T-helper cell type responses. Specifically, we show that substrate-dependent modulation of DC IL-12p40 cytokine production correlates with CD4+ T-cell proliferation and Th 1 type response in terms of IFN-γ producing T-helper cells. Furthermore, our results suggest substrate-dependent trends in DC-mediated stimulation of IL-4 producing T-cells, but this Th 2 type response is not dependent on DC production of IL-10 cytokine. This work has impact in the rational design of biomaterials for diverse applications such as tissue-engineered constructs, synthetic particle-based vaccines and the ex vivo culture of DCs for immunotherapies.
Background
Dendritic cells (DCs) are potent antigen‐presenting cells critical for immunity. We previously demonstrated a significant association between pre‐transplant blood myeloid dendritic cell ...(mDC) and plasmacytoid dendritic cell (pDC) deficiency and post‐transplant BK viremia in renal transplant recipients. In the current post‐hoc analysis, we studied the association of these same pre‐transplant DC levels with other post‐transplant outcomes.
Methods
Pre‐transplant peripheral blood mDC and pDC levels were quantified using flow cytometry in 78 patients undergoing kidney transplantation. Post‐transplant outcomes were analyzed, including infection, rejection, and patient death, with a median follow‐up of 5.3 years. Associations between DC levels and outcomes were assessed using logistic regression analysis and Cox proportional hazards models.
Results
An independent association of mDC levels with post‐transplant cytomegalovirus infection (adjusted odds ratio 7.0, P = 0.01) and patient death (adjusted hazard ratio 13.0, P = 0.015) was found. No associations were demonstrated between levels of either DC subtype and bacterial infections or rejection.
Conclusions
Pre‐transplant mDC deficiency is significantly associated with CMV infection and death after kidney transplantation.
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