Compared to "live" vaccines, the immunogenicity of "subunit" vaccines based on recombinant antigen (Ag) is poor, presumably because exogenous Ag fails to effectively access the endosomal Ag-processing pathways of Ag-presenting cells (APC). To overcome this limitation, we exploited biodegradable poly(lactic-co-glycolic) microspheres (MP) co-entrapping Ag and Toll-like receptor (TLR) 9 or 7 ligands as an endosomal delivery device. In vitro, microspheres were rapidly phagocytosed by APC and translocated into phago-endosomal compartments, followed by degradation of th...

Tumors require a constant influx of myelomonocytic cells to support the angiogenesis and stroma remodeling needed for their growth. This is mediated by tumor-derived factors, which cause sustained myelopoiesis and the accumulation and functional differentiation of myelomonocytic cells, most of which are macrophages, at the tumor site. An important side effect of the accumulation and functional differentiation of these cells is that they can induce lymphocyte dysfunction. A complete understanding of the complex interplay between neoplastic and myelomonocytic cells...

As dendritic cells (DC) are rare populations in all organs, their generation from hematopoietic precursors in large quantities has proven critical to study their biology. From murine bone marrow about 5 x 10(6) cells at 70% purity are obtained per mouse after 8 days of culture with GM-CSF. We have improved this standard method and routinely achieve a 50-fold higher yield, i.e., 1-3 x 10(8) immature and mature DC per mouse at 90-95% purity. The major modifications were: (i) the avoidance of any active depletion of bone marrow cell subpopulations to circumvent loss...

BACKGROUND: Microarrays are routinely used to assess mRNA transcript levels on a genome-wide scale. Large amount of microarray datasets are now available in several databases, and new experiments are constantly being performed. In spite of this fact, few and limited tools exist for quickly and easily analyzing the results. Microarray analysis can be challenging for researchers without the necessary training and it can be time-consuming for service providers with many users. RESULTS: To address these problems we have developed an automated microarray data analysis...

BACKGROUND AND AIMS: Cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) has been shown to act as a negative regulator of T cell function and has been implicated in the regulation of T helper 1 (Th1)/Th2 development and the function of regulatory T cells. Tests were carried out to determine whether anti-CTLA-4 treatment would alter the polarisation of naive T cells in vivo. METHODS: Mice were treated with anti-CTLA-4 monoclonal antibody (mAb) (UC10-4F10) at the time of immunisation or colonic instillation of trinitrobenzene sulfonic acid (TNBS). The cytokines pr...

Interferon (IFN)-gamma, a cytokine critical for resistance to infection and tumors, is produced by CD4(+) helper T lymphocytes after stimulation by cultured dendritic cells (DCs) that secrete a cofactor, interleukin (IL)-12. We have identified a major IL-12-independent pathway whereby DCs induce IFN-gamma-secreting T helper (Th)1 CD4(+) T cells in vivo. This pathway requires the membrane-associated tumor necrosis family member CD70 and was identified by targeting the LACK antigen from Leishmania major within an antibody to CD205 (DEC-205), an uptake receptor on a ...

The TPL-2 MEK kinase is essential for activation of the Erk MAP kinase pathway during innate immune responses. TPL-2 is found in complex with ABIN-2 (A20-binding inhibitor of NF-kappaB 2). Here, using antigen-presenting cells from ABIN-2-deficient mice, we show that ABIN-2 was required for optimal activation of Erk induced by receptors that signal via TPL-2, including Toll-like receptor 4 and tumor necrosis factor receptor 1 in macrophages, and CD40 in B cells. ABIN-2 was necessary for the maintenance of TPL-2 protein stability. In contrast, ABIN-2 deficiency did...

Dendritic cells (DCs) are an attractive tool for immunomodulation, targeting mature DCs (mDCs) for immunization or immature/semimature DCs (iDCs) for tolerization. Therefore, introducing antigens into DCs has become a prime topic in various immunological disciplines. Numerous studies have shown that lentiviruses are an efficient vehicle for this purpose. This study evaluates the effects of lentiviral transduction on iDC activation. Immature DCs are efficiently transduced with increasing doses of lentivirus without affecting cell viability. Transduction at low mul...

In this study, we compared dendritic cells (DCs) differentiated from positively selected monocytes (CD14-DCs) to DCs differentiated from adherence-selected monocytes (adh-DCs) with emphasis on lentiviral transduction. Using a second-generation, triple-helix containing, self-inactivating lentiviral vector at a multiplicity of infection (MOI) of 15, we observed enhanced transduction of CD14-DCs (72.8 +/- 5.3%, mean fluorescence intensity [MFI] = 166 +/- 76) compared to adh-DCs (32.3 +/- 13.1%, MFI = 119 +/- 76, n = 5). More importantly, the efficiency to transduce ...

We reviewed 66 women with poor-risk metastatic breast cancer from 15 centers to describe the efficacy of allogeneic hematopoietic cell transplantation (HCT). Median follow-up for survivors was 40 months (range, 3-64). A total of 39 patients (59%) received myeloablative and 27 (41%) reduced-intensity conditioning (RIC) regimens. More patients in the RIC group had poor pretransplant performance status (63 vs 26%, P=0.002). RIC group developed less chronic GVHD (8 vs 36% at 1 year, P=0.003). Treatment-related mortality rates were lower with RIC (7 vs 29% at 100 days...

The intestinal innate immune system continually interacts with commensal bacteria, thus oral vaccines should induce extra/alternative activation of DC, potentially through TLR. To examine this we collected intestinal lymph DC (iL-DC) under steady-state conditions and after feeding resiquimod (R-848), a synthetic TLR7/8 ligand, which we showed induces complete emptying of gut DC into lymph. iL-DC are heterogeneous with subset-specific functions. In this study we determined the kinetics of iL-DC subset release, activation and cytokine secretion induced by R-848. We ...

To identify the molecular basis underlying the functions of tumor-associated macrophages (TAMs), we characterized the gene expression profile of TAMs isolated from a murine fibrosarcoma in comparison with peritoneal macrophages (PECs) and myeloid suppressor cells (MSCs), using a cDNA microarray technology. Among the differentially expressed genes, 15 genes relevant to inflammation and immunity were validated by real-time polymerase chain reaction (PCR) and protein production. Resting TAMs showed a characteristic gene expression pattern with higher expression of g...

Dendritic cells (DCs) are professional APCs of the immune system that play a key role in regulating T cell-based immunity. The capacity of DCs to activate T cells depends on their maturation state as well as their ability to migrate to the T cell areas of draining lymph nodes. In this study, we investigated the effects of DC maturation stimuli on the actin cytoskeleton and beta(1) integrin-dependent adhesion and migration. Podosomes, specialized adhesion structures found in immature monocyte-derived DCs as well as myeloid DCs, rapidly dissolve in response to matu...