Heterogeneity of adherent and non‑adherent JAWS II dendritic cells

Dendritic cells (DCs) are crucial in the development of immune responses. DC JAWS II is a murine cell line frequently used in DC studies. These cells are grown in two cell fractions: Adherent and non-adherent. The present study aimed to compare these two fractions in both immature and lipopolysaccharide (LPS)-activated JAWS II cells. The present study analysed the condition, phenotype, antigen uptake capability, signalling properties and the influence on the activity of T cells using flow cytometry, mixed cell reaction and ELISA methods. Adherent immature JAWS II cells exhibited increased endocytosis and decreased activation of the Pi3K signalling pathway. After LPS activation, adherent JAWS II cells exhibited increased expression levels of CD80 and CD86 costimulatory molecules, increased endocytosis and an elevated ability to induce T cell proliferation, compared with non-adherent cells. These results demonstrated that the two fractions of JAWS II adherent and non-adherent cells exhibited different properties and this should be taken into account in the planning of research.

Importance of TGFβ in Cancer and Nematode Infection and Their Interaction-Opinion

Historically, there has been little interaction between parasitologists and oncologists, although some helminth infections predispose to the development of tumours. In addition, both parasites and tumours need to survive immune attack. Recent research suggests that both tumours and parasites suppress the immune response to increase their chances of survival. They both co-opt the transforming growth factor beta (TGFβ) signalling pathway to modulate the immune response to their benefit. In particular, there is concern that suppression of the immune response by nematodes and their products could enhance susceptibility to tumours in both natural and artificial infections.

Reduced Expression of PD-1 in Circulating CD4+ and CD8+ Tregs Is an Early Feature of RRMS

Altered regulatory T cell (Treg) function could contribute to MS. The expression of activating and inhibitory receptors influences the activity of Tregs. Our aim was to investigate T cell phenotypes in relapsing-remitting MS (RRMS) patients at an early phase of the disease. We examined the influence of demographic parameters on the distribution of CD4+ and CD8+ T cell subclasses by generalized linear modeling. We also studied the expression of the following markers-CTLA-4, GITR, PD-1, FoxP3, Helios, CD28, CD62L, CD103-on T cell subsets from peripheral blood with a 14-color flow cytometry panel. We used an antibody array to define the profiles of 34 Th1/Th2/Th17 cytokines in the serum. Expression of PD-1 and GITR on CD4+ and CD8+ Tregs was decreased in RRMS patients. The proinflammatory factors IFN-γ, IL-17, IL-17F, TGFβ-1, TGFβ-3, IL-1SRII, IL-12 p40, sgp130, IL-6sR were significantly increased in RRMS patients. Therefore, a deficiency of PD-1 and GITR immune checkpoints on CD4+ and CD8+ Tregs is a feature of RRMS and might underlie impaired T cell control.

Cyclosporine A, in Contrast to Rapamycin, Affects the Ability of Dendritic Cells to Induce Immune Tolerance Mechanisms

Following organ transplantation, it is essential that immune tolerance is induced in the graft recipient to reduce the risk of rejection and avoid complications associated with the long-term use of immunosuppressive drugs. Immature dendritic cells (DCs) are considered to promote transplant tolerance and may minimize the risk of graft rejection. The aim of the study was to evaluate the effects of immunosuppressive agents: rapamycin (Rapa) and cyclosporine A (CsA) on generation of human tolerogenic DCs (tolDCs) and also to evaluate the ability of these cells to induce mechanisms of immune tolerance. tolDCs were generated in the environment of Rapa or CsA. Next, we evaluated the effects of these agents on surface phenotypes (CD11c, MHC II, CD40, CD80, CD83, CD86, CCR7, TLR2, TLR4), cytokine production (IL-4, IL-6, IL-10, IL-12p70, TGF-β), phagocytic capacity and resistant to lipopolysaccharide activation of these DCs. Moreover, we assessed ability of such tolDCs to induce T cell activation and apoptosis, Treg differentiation and production of Th1- and Th2-characteristic cytokine profile. Data obtained in this study demonstrate that rapamycin is effective at generating maturation-resistant tolDCs, however, does not change the ability of these cells to induce mechanisms of immune tolerance. In contrast, CsA affects the ability of these cells to induce mechanisms of immune tolerance, but is not efficient at generating maturation-resistant tolDCs.

Immunomodulatory potential of nematodes against dendritic cells is dependent on intestinal inflamation

The mouse intestinal parasite Heligmosomoides polygyrus demonstrates adaptation to the inflammatory milieu as a result of colitis induced by dextran sulphate sodium (DSS). Nematodes from mice with colitis had different effects on dendritic cells than nematodes from mice without colitis. Immature JAWSII cells pre-exposed to L4 stage H. polygyrus from DSS-treated mice were adoptively transferred to mice with induced colitis. After two days, a higher disease activity index, macroscopic damage score and colon histology score were observed. MLN T cells isolated nine days after transfer demonstrated proinflammatory IFN-γ and IL-17 production. Transfer of JAWSII stimulated with male or female L4 larvae from a control invasion resulted in a slight improvement of colitis; in addition, dendritic cells exposed to H. polygyrus female L4 larvae, provoked migration of CD8⁺CD25⁺ T cells from MLN to the colon. Nematodes from an inflammatory environment changed cytokine production by dendritic cells. Inflammatory milieu changing nematode immunomodulatory activity affects dendritic cell functions, which offers new insight into the helminth-host relationship.

Effects of intestinal nematode treatment on CD11b activation state in an EAE mouse model of multiple sclerosis

The experimental autoimmune encephalomyelitis (EAE) animal model of Multiple Sclerosis (MS) is characterized by episodic neurologic dysfunction arising as a consequence of perivascular mononuclear cell infiltration and demyelination in the CNS. Leukocyte integrins, which are responsible for migration through the endothelial, play key roles in the pathogenesis of autoimmune diseases and chronic inflammation. Intestinal infection of mice with Heligmosomoides polygyrus appears to target CD11b (integrin αM), which is highly expressed on myeloid cells and is critical for their migration and function. H. polygyrus infection induces suppression of ongoing experimental EAE and extensive infiltration of CD11b⁺ cells to the CNS. Therefore, the aim of the present study was to characterize the phenotype and activity of CD11b⁺ cells accompanying the tissue phase infection of L4 H. polygyrus in EAE mice. It was found that the cells displayed a CD11b⁺ state with a distinct phenotype characterised by the expression of co-stimulatory CD80/CD86, CD40, MHCII, F4/80 and the mannose receptor CD206. This activation state illustrates the heterogeneity of CD11b⁺ cells in EAE mice following nematode invasion; these may have important consequences for understanding the effects of CD11b integrin, which is involved in the downregulation of neuroinflammatory disorders.

The Effects of T4 and A3/R Bacteriophages on Differentiation of Human Myeloid Dendritic Cells

Bacteriophages (phages) are viruses of bacteria. Here we evaluated the effects of T4 and A3/R bacteriophages, as well as phage-generated bacterial lysates, on differentiation of human myeloid dendritic cells (DCs) from monocytes. Neither of the phages significantly reduced the expression of markers associated with differentiation of DCs and their role in the activation of T cells (CD40, CD80, CD83, CD86, CD1c, CD11c, MHC II, PD-L1, PD-L2, TLR2, TLR4, and CCR7) and phagocytosis receptors (CD64 and DEC-205). By contrast, bacterial lysate of T4 phage significantly decreased the percentages of DEC-205- and CD1c-positive cells. The percentage of DEC-205-positive cells was also significantly reduced in DCs differentiated in the presence of lysate of A3/R phage. Thus while bacteriophages do not substantially affect differentiation of DCs, some products of phage-induced lysis of bacterial cells may influence the differentiation and potentially also some functions of DCs. Our results have important implications for phage therapy of bacterial infections because during infections monocytes recruited to the site of inflammation are an important source of inflammatory DCs.