Abstract This paper looks at the lymphatic system and the immune system. It compares blood, lymph and interstitial fluid, and compares lymph nodes with the spleen. It then examines humoral and cell-mediatedimmunity, primary and secondary immune responses, and the role of complement.
Tags: lymph, complement, cell-mediated vs humoralimmunity
Abstract This paper begins with the presentation of a flowchart highlighting the body's immune system response at the cellular level incorporating both the cellmediated and humoralimmune systems. Following this, a discussion of the immune system's response to the presence of an allergen is discussed and how allergy treatments affect the immune system response.
From the Paper "The human body has two main components to its immune system: the Cell Mediated Response and the Humoral Response. While both are unique responses of the immune system, there is strong interplay between the two. The following flowchart will present the immune system's response to attack. The presence of an allergen is not generally a life-threatening situation requiring a full immunological response, however, that is often exactly what happens. The following section will discuss the various components of the immune system that are involved in an allergic response and how treatment of allergies affects the immune system. In response to an allergen, the immune system mounts a defense. There is dispute in the medical community whether an allergen is actually a foreign substance or not (Dr. Danielle West, personal communication, January 17, 2006) however the key is how the immune system reacts to"
Abstract This paper explains that the immune system generates numerous unusual kinds of immune reactions. For example, the body annihilates eukaryotic cells having or bearing foreign cell-surface antigens. These include cancer cells, whose cell-surface antigens are distorted when a normal cell is genetically changed into a cancer cell. The antigen-bearing cell may be eaten by macrophages or killed by killer cells, which are specialized to destroy abnormal body cells. The paper examines how the immune system functions, looking at physiological processes such as cellular immunity and humoralimmunity.
From the Paper "Humoral immunity is best explained as if the virus has not yet invaded a body cell, it may be surfaced by antibody molecules that may have been secreted into the body fluids by B cells. The virus-antibody is then eaten and destroyed by a phagocyte."
A descriptive overview of the vertebrate adaptive immune response to both intra and extra-cellular pathogens with explicit focus on T-cell B-cell collaboration and antibody response.
Abstract This paper covers the major pathways by which foreign antigens are identified and dealt with through the adaptive immune response which is paramount on B-cell and T-cell responses and interaction with one another in distinct pathways and steps. It includes several diagrams and their explanations of antigens, B-Cells, T-Cells, APC's and more and their interactions and processes they go through.
From the Paper "All immune responses involving T-cell B-cell collaborations follow distinct pathways of interactions and development. These very pathways of the adaptive immune response are almost entirely dependant on the cellular interaction of B- cells and T- cells with one another. It is within each stage of these pathways and the progression of an adaptive immune response that we will concern ourselves. The following is a condensed synopsis of the adaptive immune response and the cellular interactions that will be the emphasis of this paper. Within secondary lymph tissues foreign antigen is presented to naive B-cells via their surface immunoglobulins (Igs) receptors. The same antigen is also presented to naive T-cells at this time. This presentation and subsequent recognition of antigen by both types of cells results in and end product of proliferation and development of naive B-cells into plasma cells whose function is the production of soluble immunoglobulins (antibodies), and the differentiation and development of memory B-cells whose function is to respond to subsequent exposure to the same antigen. However, this pathway is not self-sufficient and requires the direct interaction of activated T-cells, specifically "helper" T-cells (Th2 cells) 1,9. It is these T-cells in conjunction with the antigen presenting B-cells that interact to produce a hormonal response to infection. These interactions activate Th2 cells that in turn promote B-cell activation both through T-cell secreted cytokines, (interlukeinI1-2, 4 and 5), and also through direct cell to cell contacts involving specific surface proteins and corresponding receptors and the signaling initiated by the binding of these proteins to one another."
Abstract This paper discusses the problem of medicine's inability to induce antigen-specific immune tolerance, the final technical obstacle to bringing face transplants into widespread clinical application. The paper presents an overview of historic and current immunological research - from the use of chimerism, to the use of monoclonal antibodies to control T-cell activation - and its role in future prospects for a non-pharmaceutical strategy for tolerance induction in humans. The paper highlights studies that have examined tolerance in recipients of composite tissue allografts (CTAs), with emphasis on studies using animal models involving skin allografts, and with the intent of providing insight into the issues presented by transplantation of a face. It includes graphs and photographs to illustrate this.
Outline:
Abstract
Introduction
CTA Study Goals
Antigenicity of Facial Allograft Components
Immune Tolerance and Chimerism
T-cells: Activation and Blockage
Memory Cells: The Ghost in the Immune Machine
Conclusion
From the Paper "Investigators are exploring several strategies in an attempt to provide medicine with safe and effective pharmaceuticals and clinical protocols for inducing tolerance after transplant. These include creating and using chimerism, and developing targeted bio-engineered monoclonal antibodies to inactivate or destroy T cells. This review, in its overview of historical and current immunological research, provides insight into the development of a T-cell-based strategy from a basic understanding of chimerism. This review also highlights studies that examine tolerance in recipients of CTA transplants, with specific emphasis on those using skin allograft animal models."
Tags: medical, operation, plastic, surgery, anti-immune, system
Abstract This paper defines what are known as stem cells and what is involved in stem cell (SC) transplantation, and provides a list of current uses for SC transplantation. The writer explains that most common sources for such transplants are bone marrow, blood and cord blood stem cells, and describes in detail how bone marrow and cord blood stem cells are obtained and what is entailed in bone marrow transplantation (BMT). Despite considerable progress in BMT over the years, there are still major problems with graft-versus-host disease (GVHD), failure to engraft and lack of suitable donors. The writer notes that younger donors and good transplant timing lead to better transplant outcomes, and suggests that in the future, emphasis should be on better control of GVHD with novel immunosuppressive and other immunomodulatory agents. This paper contains tables.
Outline:
Introduction
Application of SCs in Transplantation
Types of Disorders Treated
Types of SC Transplants Available
Availability & Collection of Different Sources
Bone Marrow Registries
Cord Blood Banks
Donor Search
Growth Factors
Harvesting
PBSC Harvesting
Cord Blood Harvesting
Risks for Donors
Ethical Issues Regarding the Sources
Outcome of SC Transplantation
Factors Affecting the Outcome
Conditioning Regimen
Non-myeloablative Allogeneic HSCT
Time for Engraftment or Immune Reconstitution
Transplant Related Mortality
Relapse
Role of HLA Compatibility
Effect of Other Cells in the Graft in GVHD and GVL, and the Balance of GVHD and GVL
Conclusion
From the Paper "The sources for allogeneic stem cell transplant include: half-matched family members, unrelated adult volunteer donors, and related or unrelated umbilical cord blood units (CBU) (Burt & Brush, 1999). The ideal allogeneic bone marrow donor for a patient would be a monozygotic twin, since this transplant is not only HLA-matched but also matched for all other genetic loci. A transplant can be done if a related donor with only one HLA difference is identified, although there is a risk of GVHD. For those without siblings or other related donors, unrelated bone marrow donors would be the only option (Carella et al, 2001)."
Abstract At the beginning of the millennium life expectancy doubled to approximately 80 years of age, compared to what it was in 1900. This paper studies the new field of immunogerontology that explores the immune system in the aging adult. Recent research has indicated that the immune systems of aged people undergo characteristic changes, generally in the direction of decreased immune competence. As the research presented in this paper reveals, aging affects many aspects of the immune process, and since the immune system interacts with every system of the body it becomes important to have a well-developed understanding of the mechanisms related to the breakdown of this system in the later years of life.
From the Paper "Malnutrition in aging populations is another mechanism, which contributes to the decline in the efficiency of the signal transduction system and as a result leads to the degradation of the immune response. Calcium is an integral part of the signaling mechanism and the biochemical pathways that compose it. Enzymes necessary for T cell proliferation are rendered useless in the absence of calcium as shown by Miller et al (1996). Measurements made in the lab of IL-2 production were shown to be substantially lower than in T cells belonging to younger individuals. It is important to remember that IL-2 is produced after the antigen binds to the receptor-binding site and is responsible for promoting the proliferation of the T cell. Though these experiments are mainly carried out on mice, the biochemical pathways are very similar and results tend to indicate that immunodeficiency in the aging adult is due in part to the decline in calcium concentrations. Other nutrients such as zinc and vitamin E are also important in the proper functioning of the immune system affecting cytokine production and imparting a protective role from damage by free radicals respectively (Moriguchi, 1998)."
Abstract This paper explains that stem cells intended for use in human applications are harvested from humans, umbilical cords, and embryos, and are so valuable because they are master cells with the capability to produce or "become" any other cell type. The author points out that the reason for the discourse surrounding the topic of stem cells is the fact that the most promising source of stem cells is human fetal tissue; thus, many who hold anti-abortion views find this practice to be highly immoral and repugnant. The paper relates that the problem with umbilical cord stem cells is the small amount that can be harvested from any particular cord; adult stem cells, which pale in comparison to the ability of embryonic cells to differentiate into specialized cells, can be used for research.
From the Paper "Of course, most people know the origin of human life begins with the sperm fertilizing the egg. After this, a single cell is created that holds all of the genetic information needed to form the entire human body. This cell divides and redivides over several days until these cells (known as totipotent, or as having "total potential") begin to specialize into the formation known as the ?blastocyst,? which has a hollow sphere of cells, and a cluster of inner cells (the inner cell mass). While the outer cells of this blastocyst proceed to form the placenta, the cells within the inner cell mass go on to form virtually all of the tissues and organs of the human body. It is these cells that are harvested to research stem cells."
This paper examines the social, moral and ethical merits of stem cell research, as well the ongoing political debate regarding the funding for continued research in this controversial field of science.
Abstract This paper defines stem cells as primal undifferentiated cells which retain the ability to separate into other cell types which can be used as a repair mechanism to reproduce cells and repair systems in the body. The writer examines the negative side of stem cell research contending that there is evidence which states that the impact of this type of research on the human immune system as well as overall genetic growth will eventually decline. This paper also discusses the moral and ethical merits of stem cell research which is currently rife with controversy. Politics plays a large role in stem cell development, mainly due to funding. The writer contends that stem cells are too dangerous to be carelessly used and applied to the human race, while its continued research might be slightly beneficial, in the current stage the harms far outweigh the benefits.
From the Paper "The first step in analyzing the effects of stem cell research is through the scientific perspective. Stem cell research is important for the advancement of science because of its ability to replicate exact copies of different cells. Stem cells are obtained from a clone of the specific patient's cells, and thus have a genetically identical fit with a stem cell. This cell then has the ability to produce either missing tissue, or even an entire organ that will allow the patient to function as normal. Unlike transplants within the body that could be rejected by the immune system if there is a possibility of incompatibility, the stem cell created organ is a perfect construction of the body's organ and thus will be accepted as the original inside the patient's body. This is why stem cell research is so highly touted, it allows for a new frontier of technology in the health sciences industry."
Abstract The paper describes the general features of the adaptive immune system (especially in relation to innate immunity) in vertebrates, delineates the processes that took place for this complex system to evolve and the reasons behind its evolution.
From the Paper "Microscopic organisms are the most ubiquitous form of life throughout the biosphere. Many of them are parasitic and cause disease. To protect themselves against invasion by pathogens and even cells from an organism of the same species, all animals possess the means to systematically distinguish and eliminate non-self. Based on the diversity, flexibility and specificity of recognition and effector mechanisms, however, the complexity of this system varies across metazoan phyla. From relatively simple histocompatibility reactions mediated by interleukin-like proteins in sponges, to sophisticated interplay of the innate and adaptive immunity in jawed vertebrates, the increased intricacy of the immune response is positively correlated with such features as: complex morphology, increased size and lifespan as well as K-selected reproductive strategy. Thus, the fact that vertebrates exhibit all of the aforementioned characteristics may be the key reason why they are the only group of animals with an adaptive immunity."
This paper explains that stem cell research is leading scientists to investigate the possibility of treating disease with cell-based therapies, often referred to as regenerative or reparative medicine.
Abstract This paper relates that implanted stem cells used to repair or replace damaged tissues are less likely to be rejected by the body's immune system than other foreign cells. The author points out that germ line cells and adult stem cells are less versatile than embryonic stem cells, which can develop into every type of tissue found in an adult; however, the processes that control this development are at present not fully understood. The paper discusses that BioMark International, a privately funded Biotech Group, provides access to a unique method of Cord Blood Stem Cell (CBSC)processing by which CBSCs are derived from the umbilical cords from natural full term births of consenting mothers, all of whom have been tested according to standards set by the American Association of Blood Banks .
From the Paper "In May 2004, Nancy Reagan, whose husband former President Ronald Reagan was at the time suffering the advanced stages of Alzheimer's disease, urged the Bush administration to support embryonic stem cell research and said that too much time had been wasted discussing the issue. Although a Republican, Mrs. Reagan has been critical of the Bush administration for blocking public funding of stem cell research due to the party's ethical reservations concerning embryo research. Speaking at a fundraising dinner for the Juvenile Diabetes Research Foundation, she said she believed the research could lead to a cure for Alzheimer's disease, and "may provide our scientists with many answers that for so long have been beyond our grasp...I just don't see how we can turn our backs on this...We have lost so much time already...I just really can't bear to lose any more.""
Abstract This paper begins with a description of the process for creating and harvesting human embryonic stem cells and then explains why this process is so disturbing to most people and thus serves as the foundation for their opposition to the procedure. The paper then discusses the many ways that human embryonic stem cells could be used to cure a variety of painful and life-threatening illnesses such as leukemia, immune deficiencies and diabetes. Next, the paper discusses the objections to the use of stem cells that are based on religious viewpoints and opinions, as well as the legal and ethical issues regarding the use of stem cells. The paper concludes that when one considers that embryonic stem cell research may result in curing forever diseases like Parkinson's and Alzheimer's, the ethical and religious concerns of the opposition melt away and thus open the proverbial door to a future without pain and suffering and to a longer and healthier lifespan.
From the Paper "In August of 2001, President Bush responded to the debate behind this bill on national television. At the start of his speech to the American viewing public, Bush points out that he is about to discuss "a complex and difficult issue. . . one of the most profound of our time," being the controversy over medical research involving stem cells taken from human embryos. Bush then mentions that this issue "is debated within the church, with people of different faiths" with even many "of the same faith coming to different conclusions." Obviously, most of the debate behind using stem cells from human embryos is based upon religious viewpoints and opposition, due to the fact that the dissenters believe that human life begins with the creation of a fertilized egg known as conception. Bush adds that most of these dissenters "are finding that the more they know about stem cell research, the less certain they are about the right ethical and moral conclusions" . However, Bush also adds that based on some privately-funded research, scientists believe that "further research using stem cells offers great promise" for the future in relation to improving if not curing many common disease like Alzheimer's, juvenile diabetes, Parkinson's and spinal cord injuries."
An argument that embryonic stem cell research is not unethical because the benefits derived from the research outweigh the moral obligations to the fetus.
Abstract This paper explores the ethical dilemma regarding embryonic stem cell research that is based on the fact that embryos donated for in vitro fertilization are destroyed once stem cells are extracted from them for study. The paper focuses on President Bush's objections that have caused federal funding of stem cell research to remain illegal. The paper then deals with the potential benefits of stem cell research and contends that the research is a priority that should not get delayed by moral issues. The paper further argues that these embryonic stem cells are otherwise destroyed if they are not used for life saving research purposes.
From the Paper "Stem cells are seen as a new hope and frontier of science. By Conservatives they are seen as overt moral disregard for the sanctity of life. However, this is not a debate that can be easily judged or dismissed. An understanding of the dynamic nature of stem cells can inform all as to the ultimate benefits and appeals of stem cells for scientific research and achieve a proportionate understanding of the true means by which the practice is called immoral by right-to-lifers who are faith based.
"Stem cells are not the end of life, but to scientists represent the potential achievement of a bridge to a higher level of living and health and curative process. Stem cells have the potential to develop into various and virtually unlimited forms of regenerative cells in the body. They are dynamic in nature so that the body can instinctively transform and utilize them as repair cells for whatever affliction, malady, or infection plaguing the immune system of the body."
Abstract This essay describes key components of the immune system and how the body uses this system. Also discussed is the cause and effect relationship between stress, the immune system, and certain diseases. Articles listed in the bibliography of this paper are also appended.
From the Paper "How quickly a deceased human (or animal) body breaks down is testament to how well the immune system works. While a body is alive, the immune system protects the body at every living moment from bacteria and other foreign invaders. The immune system is a complex system of cells"which have varying functions"and generated at discreet regions of the body, a circulatory system?the lymphatic system--that feeds of and into the blood circulatory system and lymph nodes that act as effective filters and stores of foreign bodies marked for destruction by antibody action. Most of the time, the immune system protects the body. But on rare occasions we might need outside help: this is when he system does not "figure out" the invasion and the body has to be coaxed into producing antibodies by inoculation with weaker forms of the pathogen. In the case of HIV and AIDS, the body has not been able to create an effective defense, thus these immune deficiency disorders have become the scourge of the last few decades. This essay will not only describe key component of the immune system and how a body uses this system, but will also explore the cause and effect relationship between stress, the immune system and certain diseases."
