الفهرس 
PRINCIPLES OF IMMUNE RESPONSEOnly 14 pages are availabe for public view
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Abstract
S
ubstantial progress has been made in the field of Immunotherapy 100 years ago. We have summarized the role of immunotherapy in treating allergic diseases as well as malignancies
As discussed, the immune system has evolved to protect the host from a universe of pathogenic microbes that are themselves constantly evolving. The immune system also helps the host eliminate toxic or allergenic substances that enter through mucosal surfaces. Central to the immune system’s ability to mobilize a response to an invading pathogen, toxin, or allergen is its ability to distinguish self from nonself. The host uses both innate and adaptive mechanisms to detect and eliminate pathogenic microbes, and both of these mechanisms include self-nonself discrimination. Although, the immune system is a remarkably effective structure that incorporates specificity, inducibility and adaptation, failures of host defense do occur, and fall into three broad categories: hypersensitivities, immunodeficiencies, and autoimmunity
Immunotherapy, in medicine, refers to an array of treatment strategies based upon the concept of modulating the immune system to achieve a prophylactic and/or therapeutic goal.
Allergen-SIT represents a potentially curative and specific approach to allergies. Clinical trials of allergen-SIT demonstrate treatment efficacy in various allergic diseases such as allergic asthma, allergic rhinitis, stinging insect hypersensitivity and aero-allergen-induced atopic dermatitis in patients whose symptoms are clearly driven by allergic triggers.
Perhaps surprisingly, we are still unsure exactly how SIT works, but we do know that SIT induces regulatory T cells that dampen the response to allergen exposure in sensitized subjects. Recent developments on molecular mechanisms of immune regulation in the area of allergy have provided substantial knowledge on allergen-tolerance. The induction of peripheral T cell tolerance by Treg cells is a key point in the suppression of allergic inflammation. FOXP3+CD4+CD25+ Treg cells and Tr1 cells secrete suppressive cytokines such as IL-10 and TGF-β, and lead to the production of non-inflammatory antibody subtypes such as IgG4 and IgA. Novel suppressive cell subsets and cytokines such as Breg cells and IL-35 may form targets for new SIT approaches. The understanding of the molecular processes enables us to better understand the regulation of the immune response.
When used in appropriately selected patients, SIT is effective and safe, but care is needed to recognize and treat adverse reaction which can be classified in two categories: local reactions appearing as erythema, pruritus and swelling at the injection site of SCIT; and systemic reactions appearing as anaphylaxis from mild to serious life-threatening severity. As well as careful patient selection, appropriate training of allergists and SIT clinic support staff is essential. Such side effects are one of the difficulties of SIT to be overcome. Future directions in SIT will include the development of better standardized vaccines and the use of recombinant allergens, both of which should improve the safety profile of SIT. Novel vaccines are expected to shorten the duration, decrease the side effects and increase the efficiency of the treatment. In parallel, the development of allergen-independent immunomodulatory therapies might allow more general approaches to be developed, which would be particularly advantageous for those patients who are sensitized to multiple allergens.
Different time regimes are used for the administration of the first vaccinations. Currently ultra-rush procedures are efficiently used in hymenoptera allergy SIT . An increase in Treg cells along with a Th2 to Th1 switch has been shown to occur already during the first 24 h This type of time regime is now also being investigated in SLIT.
The existing evidence for dysfunction and death of antitumor effector cells in tumor-bearing hosts introduces a new paradigm for immunotherapy of cancer. Although previous emphasis has been on activation of immune cells and upregulation of their antitumor functions, the current concept is to consider therapies that could block or reverse tumor escape, at the same time protecting immune cells from the influence of immunosuppressive factors present in the tumor microenvironment. These novel therapeutic strategies take advantage of the tremendous progress made recently in our basic understanding of interactions between the tumor and the host immune system. Current insights into these interactions suggest that combinations of conventional cancer therapies with newly designed DC-based vaccines and survival cytokines (eg, IL-2, IL-7, and IL-15) offer therapeutic benefits. It is expected that as molecular mechanisms used by tumors to avoid, bypass, or subvert the immune system of the host are becoming clear, novel and more effective antitumor therapies targeting these mechanisms will emerge in the near future.
As a conclusion, immunotherapy research holds enormous potential for contributing to our understanding of fundamental human immunity. Although it is not possible to predict the outcomes from basic research, such studies will offer the real possibility for treatments and ultimately for cures for many diseases for which adequate therapies do not exist.