Frontiers in immunology
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Frontiers in immunology · Jan 2018
Streptococcus Suis Serotype 2 Stimulates Neutrophil Extracellular Traps Formation via Activation of p38 MAPK and ERK1/2.
Streptococcus suis serotype 2 is a major pathogen of swine streptococcicosis, which result in serious economic loss worldwide. SS2 is an important zoonosis causing meningitis and even death in humans. Neutrophil extracellular traps (NETs) constitute a significant bactericidal strategy of innate immune. ⋯ Blocking TLR4 signaling could further inhibit the activation of ERK1/2, but not p38 MAPK; however, TLR4 signaling inhibition reduced NETs formation induced by SS2. In conclusion, SS2 could be recognized by TLR2 and/or TLR4, initiating NETs formation signaling pathways in a NADPH oxidase derived ROS dependent manner. ROS will activate p38 MAPK and ERK1/2, which ultimately induces NETs formation.
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Frontiers in immunology · Jan 2018
ReviewTargeting B Cell Maturation Antigen (BCMA) in Multiple Myeloma: Potential Uses of BCMA-Based Immunotherapy.
The approval of the first two monoclonal antibodies targeting CD38 (daratumumab) and SLAMF7 (elotuzumab) in late 2015 for treating relapsed and refractory multiple myeloma (RRMM) was a critical advance for immunotherapies for multiple myeloma (MM). Importantly, the outcome of patients continues to improve with the incorporation of this new class of agents with current MM therapies. However, both antigens are also expressed on other normal tissues including hematopoietic lineages and immune effector cells, which may limit their long-term clinical use. ⋯ Other promising BCMA-based immunotherapeutic macromolecules including bispecific T-cell engagers, bispecific molecules, bispecific or trispecific antibodies, as well as improved forms of next generation CAR T cells, also demonstrate high anti-MM activity in preclinical and even early clinical studies. Here, we focus on the biology of this promising MM target antigen and then highlight preclinical and clinical data of current BCMA-targeted immunotherapies with various mechanisms of action. These crucial studies will enhance selective anti-MM response, transform the treatment paradigm, and extend disease-free survival in MM.
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Frontiers in immunology · Jan 2018
ReviewImmunological Tolerance and Function: Associations Between Intestinal Bacteria, Probiotics, Prebiotics, and Phages.
Post-birth there is a bacterial assault on all mucosal surfaces. The intestinal microbiome is an important participant in health and disease. The pattern of composition and concentration of the intestinal microbiome varies greatly. ⋯ Hence bacteriophage local control of inflammation and immune responses may be an additional immunological defense mechanism that exploits bacteriophage-mucin glycoprotein interactions that controls bacterial diversity and abundance in the mucin layers of the gut. Moreover, and importantly the efficacy of probiotics may be dependent on the symbiotic incorporation of prebiotics, and the abundance and diversity of the intestinal microbiome encountered. The virome may be an important factor that determines the efficacy of some probiotic formulations.
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Frontiers in immunology · Jan 2018
ReviewCD38 Antibodies in Multiple Myeloma: Mechanisms of Action and Modes of Resistance.
MM cells express high levels of CD38, while CD38 is expressed at relatively low levels on normal lymphoid and myeloid cells, and in some non-hematopoietic tissues. This expression profile, together with the role of CD38 in adhesion and as ectoenzyme, resulted in the development of CD38 antibodies for the treatment of multiple myeloma (MM). At this moment several CD38 antibodies are at different phases of clinical testing, with daratumumab already approved for various indications both as monotherapy and in combination with standards of care in MM. ⋯ Differences in frequency or activity of effector cells may also contribute to differences in outcome. Furthermore, the microenvironment protects MM cells to CD38 antibody-induced ADCC by upregulation of anti-apoptotic molecules, such as survivin. Improved understanding of modes of action and mechanisms of resistance has resulted in rationally designed CD38-based combination therapies, which will contribute to further improvement in outcome of MM patients.
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Frontiers in immunology · Jan 2018
ReviewThe Emerging Role of CD8+ Tissue Resident Memory T (TRM) Cells in Antitumor Immunity: A Unique Functional Contribution of the CD103 Integrin.
Cancer immunotherapy is aimed at stimulating tumor-specific cytotoxic T lymphocytes and their subsequent trafficking so that they may reach, and persist in, the tumor microenvironment, recognizing and eliminating malignant target cells. Thus, characterization of the phenotype and effector functions of CD8+ T lymphocytes infiltrating human solid tumors is essential for better understanding and manipulating the local antitumor immune response, and for defining their contribution to the success of current cancer immunotherapy approaches. Accumulating evidence indicates that a substantial subpopulation of CD3+CD8+ tumor-infiltrating lymphocytes are tissue resident memory T (TRM) cells, and is emerging as an activated tumor-specific T-cell subset. ⋯ Moreover, CD103 integrin triggers bidirectional signaling events that cooperate with TCR signals to enable T-cell migration and optimal cytokine production. Remarkably, TRM cells infiltrating human NSCLC tumors also express inhibitory receptors such as programmed cell death-1, the neutralization of which, with blocking antibodies, enhances CD103-dependent TCR-mediated cytotoxicity toward autologous cancer cells. Thus, accumulation of TRM cells at the tumor site explains the more favorable clinical outcome, and might be associated with the success of immune checkpoint blockade in a fraction of cancer patients.