Cover
(Source: International Immunology)
Source: International Immunology - November 25, 2015 Category: Allergy & Immunology Tags: Cover / Standing Material Source Type: research
Modulation of dendritic cell alternative activation and function by the vitamin A metabolite retinoic acid
The archetypal Th2 cytokine IL-4 has previously been shown to alternatively activate murine macrophages and, more recently, dendritic cells (DCs) both in vitro and in vivo. IL-4 has also been shown to induce Aldh1a2 (aldehyde dehydrogenase 1a2) expression in murine macrophages recruited to the peritoneal cavity. However, the influence of IL-4 on DC Aldh1a2 induction in vivo has not yet been addressed. In this work, we found that DCs show enhanced aldehyde dehydrogenase enzyme activity in vivo, which led us to investigate the impact of the vitamin A metabolite all-trans retinoic acid (RA) on DC alternative activation and fu...
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Authors: Jones, L. H., Cook, P. C., Ivens, A. C., Thomas, G. D., Phythian-Adams, A. T., Allen, J. E., MacDonald, A. S. Tags: featured content Source Type: research
Homeostatic 'bystander' proliferation of human peripheral blood B cells in response to polyclonal T-cell stimulation in vitro
The mechanisms of maintenance of adequate numbers of B lymphocytes and of protective levels of immunoglobulins in the absence of antigenic (re)stimulation remain not fully understood. Meanwhile, our results presented here show that both peripheral blood naive and memory B cells can be activated strongly and non-specifically (in a mitogen-like fashion) in 5-day in vitro cultures of anti-CD3- or concanavalin A (Con A)-stimulated peripheral blood mononuclear cells of healthy people. This polyclonal, bystander activation of the B cells includes multiple divisions of most of them (assessed here by the flow cytometric technique ...
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Authors: Jasiulewicz, A., Lisowska, K. A., Pietruczuk, K., Frackowiak, J., Fulop, T., Witkowski, J. M. Tags: Original Research Source Type: research
Common marmoset CD117+ hematopoietic cells possess multipotency
Analysis of the hematopoiesis of non-human primates is important to clarify the evolution of primate-specific hematopoiesis and immune regulation. However, the engraftment and development of the primate hematopoietic system are well-documented only in humans and are not clear in non-human primates. Callithrix jacchus (common marmoset, CM) is a New World monkey with a high rate of pregnancy and small size that lives in closed colonies. As stem cell factor (SCF) is an essential molecule for hematopoietic stem cell development in mice and humans, we focused on CD117, the SCF receptor, and examined whether CD117-expressing cel...
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Authors: Shimada, S., Nunomura, S., Mori, S., Suemizu, H., Itoh, T., Takabayashi, S., Okada, Y., Yahata, T., Shiina, T., Katoh, H., Suzuki, R., Tani, K., Ando, K., Yagita, H., Habu, S., Sasaki, E., Kametani, Y. Tags: Original Research Source Type: research
Involvement of the cytoplasmic cysteine-238 of CD40 in its up-regulation of CD23 expression and its enhancement of TLR4-triggered responses
CD40, a member of the tumor necrosis factor receptor superfamily, plays a key role in both adaptive and innate immunity. Engagement of CD40 with its natural trimeric ligand or with cross-linked antibodies results in disulfide-linked CD40 (dl-CD40) homodimer formation, a process mediated by the cysteine-238 residues of the cytoplasmic tail of CD40. The present study was designed to elucidate the biological relevance of cysteine-238-mediated dl-CD40 homodimers to the expression of CD23 on B cells and to investigate its possible involvement in the innate response. Our results indicate that cysteine-238-mediated dl-CD40 homodi...
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Authors: Nadiri, A., Jundi, M., El Akoum, S., Hassan, G. S., Yacoub, D., Mourad, W. Tags: Original Research Source Type: research
Inflammatory response of endothelial cells to a human endogenous retrovirus associated with multiple sclerosis is mediated by TLR4
The MSRV (multiple sclerosis-associated retrovirus) belongs to the human endogenous retrovirus HERV-W family. The envelope protein originating from the MSRV has been found in most patients with multiple sclerosis (MS). This protein (Env-ms) has pro-inflammatory properties for several types of immune cells and could therefore play a role in MS pathogenesis by promoting the leukocyte diapedesis observed in the central nervous system of patients. Our study aims to analyze the effects of Env-ms on the blood–brain barrier (BBB) at a molecular and functional level. We demonstrate that the recombinant MSRV envelope is able ...
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Authors: Duperray, A., Barbe, D., Raguenez, G., Weksler, B. B., Romero, I. A., Couraud, P.-O., Perron, H., Marche, P. N. Tags: Original Research Source Type: research
In This Issue
(Source: International Immunology)
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Tags: In This Issue Source Type: research
Table of Contents
(Source: International Immunology)
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Tags: Cover / Standing Material Source Type: research
Subscriptions
(Source: International Immunology)
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Tags: Cover / Standing Material Source Type: research
Cover
(Source: International Immunology)
Source: International Immunology - October 29, 2015 Category: Allergy & Immunology Tags: Cover / Standing Material Source Type: research
Innate response activator B cells: origins and functions
Innate response activator (IRA) B cells are a subset of B-1a derived B cells that produce the growth factors granulocyte macrophage colony stimulating factor and IL-3. In mouse models of sepsis and pneumonia, B-1a B cells residing in serosal sites recognize bacteria, migrate to the spleen or lung, and differentiate to IRA B cells that then contribute to the host response by amplifying inflammation and producing polyreactive IgM. In atherosclerosis, IRA B cells accumulate in the spleen, where they promote extramedullary hematopoiesis and activate classical dendritic cells. In this review, we focus on the ontogeny and functi...
Source: International Immunology - September 29, 2015 Category: Allergy & Immunology Authors: Chousterman, B. G., Swirski, F. K. Tags: Invited review Source Type: research
IL-10-independent regulatory B-cell subsets and mechanisms of action
Although classically B cells are known to play important roles in immune protection via humoral immunity, recently their regulatory mechanisms have been best appreciated in the context of autoimmunity. Several studies have identified different subsets of regulatory B cells that vary not only in their phenotype but also in their mechanism of action. Although the best-studied mechanism of B-cell immune regulation is IL-10 production, other IL-10-independent mechanisms have been proposed. These include maintenance of CD4+Foxp3+ regulatory T cells; production of transforming growth factor-β, IL-35, IgM or adenosine or exp...
Source: International Immunology - September 29, 2015 Category: Allergy & Immunology Authors: Ray, A., Wang, L., Dittel, B. N. Tags: Invited review Source Type: research
Regulatory B cells in anti-tumor immunity
Advances in understanding of the immune microenvironment have highlighted the role of immunosuppressive T cell, myeloid, dendritic and monocytic sub-populations in inhibition of the anti-tumor immune response. The role of B cells in modulating the immune response to solid tumors as well as lymphoid malignancies is less well understood. Murine models of autoimmune disease have defined B regulatory cell (Breg) subsets with immune suppressive activity, including B cell subsets that express IL-10, and transforming growth factor-β, which can facilitate T regulatory cell recruitment and expansion. Multiple murine tumor mode...
Source: International Immunology - September 29, 2015 Category: Allergy & Immunology Authors: Zhang, Y., Gallastegui, N., Rosenblatt, J. D. Tags: Invited review Source Type: research
Suppressive functions of B cells in infectious diseases
B lymphocytes are often essential to successfully control invading pathogens and play a primary role in the protection afforded by successful vaccines through the production of specific antibodies. However, recent studies have highlighted the complex roles of B cells in infectious diseases, showing unexpectedly that some activated B cells limited host defense towards pathogens. This B-cell function involves production of regulatory cytokines including IL-10 and IL-35 and is reminiscent of the regulatory functions of B cells initially defined in autoimmune diseases. It is now known that various types of microbes including b...
Source: International Immunology - September 29, 2015 Category: Allergy & Immunology Authors: Shen, P., Fillatreau, S. Tags: Invited review Source Type: research
Regulatory B cells mediate tolerance to apoptotic self in health: implications for disease
B cells are able to regulate immune responses through the secretion of IL-10 and other inhibitory cytokines, though no transcription factor that can define ‘regulatory B cells’ as a separate lineage has yet been found. Instead it is likely that this function arises as a result of the immune context in which B cells find themselves and the stimuli they perceive. However, some B cells found within the B1a and the marginal zone subsets have a greater propensity to produce IL-10 than others. What are the natural stimuli for these cells to induce immune regulation? We discuss the role that the recognition of autoant...
Source: International Immunology - September 29, 2015 Category: Allergy & Immunology Authors: Gray, M., Gray, D. Tags: Invited review Source Type: research
