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Immune System

The immune system's function is to respond to foreign pathogens and maintain defense mechanisms of the body. Inability of the immune system to react to pathogens and stimuli can cause immunlogical disorders and diseases.The immune system responses and divided into two categories:  innate and adaptive.

The innate system is passive; it acts as the first line of defense. Surface barriers that are part of the innate system can be chemical, mechanical or biological – an example is skin, which prevents pathogens from entering the body. Once pathogens enter the body a non-specific response is produced, the innate system also has no immunological memory which means that repeated exposure will produce the same response. Pathogens are identified by receptors in entry pathways, when these receptors are compromised a signal is sent. The non-specific responses are cell-mediated and they involve phagocytes, lymphocytes and cytokines.  

The second line of defense is the adaptive immune system which is trigged after failure of the innate system. This system produces specific responses to the type of pathogenic infections, and it has immunological memory – meaning information of specific pathogen is stored so that in future an enhanced response is conducted. A response is produced when the antigen of the pathogen binds to T cells or B cells, which identify and produce customized antibodies that help the breakdown of specific pathogens.

Mutations in the immune system can lead to immunodeficiency, autoimmunity and hypersensitivity. Immunodeficiency occurs when a part of the immune system is inactive or fails to respond, an example is Acquired Immunodeficiency Syndrome (AIDS). Autoimmunity is when the B and T cells cannot properly identify pathogens, and can lead to the immune system attacking the host body – example is Celiac disease. Hypersensitivity is excessive, side effect reactions that damage tissues in the body, an example is allergies.  

Basic cell function/ Case study review questions related to cystic fibrosis

Cystic Fibrosis Case Study Brad and Joanne were worried when their newborn daughter Jada seemed to have trouble gaining weight. They had two older children who never had any problems with weight gain. Jada's appetite was normal, but after meals, she seemed to be in pain. Their pediatrician suggested that it could be a result

Lymphatic system

a. give an overview of the lymphatic system b. decribe the anatomical tissues and organs that comprise the lymphatic system c. describe how familiarity with the system aids in cancer management

Bacterial Resistance to Antibiotics

Please consider (and read about as necessary) the phenomenon of bacterial resistance to antibiotics. How did the combination of human medical advances and basic evolutionary principles lead to this situation? How is it a threat to humans and how might we overcome it? Please help me to provide an accurate response.

Immune System

1. What are the mechanisms and the mediators of anaphylactic shock? Discuss the type of hypersensitivity reaction and the molecular mechanisms of anaphylactic shock. What are some possible immediate and prophylactic treatment and how do they work? 2. What are differences between the primary and secondary immune response for a

This solution explains why limiting expression of MHC class II to professional antigen presenting cells is a good strategy for regulating CD4 T cell responses against foreign but not self antigens.

While limiting the expression of MHC class II to so-called "professional" APCs partially ameliorates the problem of self non self recognition among CD4+ T cells, it remains difficult to understand how it is possible that even these cells' class II molecules are not deluged with processed "self" molecules (for example, albumin is

This solutions addresses a question regarding antibody responses to antibody allotypes within three generations of a genetically heterogeneous family. The question addresses issue of why some individuals make anti-allotype responses and why some do not.

Scenario: Amy and Hooman fell in love, got married, and had a baby named Joe. Joeâ??s grandparents are all alive and are all homozygous at IgH, but share no alleles. Joeâ??s aunts Alison and Negin are Amyâ??s and Hoomanâ??s sisters respectively. Finally, thereâ??s a cat named Tigger. Assume that you purified IgM from Hooman

Methods to sterlize instruments

How would the following items best be sterilized: a wrapped package of Petri dishes, antibiotic solution, agar media, glass pipettes and individual Petri dishes. ii) What are the advantages and disadvantages of U.V. light and ionizing radiation as sterilizing agents? iii) Compare and contrast dry heat and moist

Innate immunity to bacterial infection

An individual has a wound on the hand that gets infected with Staphylococcus aureus. Trace the entire innate immune response, assuming that the Staph is not cleared and that this is the first time this individual has seen S. aureus. The answer includes, but is not limited to: a discussion of the phagocytic response, cells invo

Myeloid lineage

Choose two of the following myeloid lineage deficiency diseases and describe their similarities and differences. chediak-higashi Chronic Granulomatous Disease Leukocyte Adhesion Deficiency

Somatic hypermutation and allelic exclusion in B cells

1. Somatic hypermutation of antibody variable regions can occur during an immune response. It allows daughter cells to produce antibodies with a slightly different V region than the parent cell. Give one reason why this might be important for the efficacy of the antibody response. Explain why mutations of the framework reg

What are the major obstacles to developing tumor vaccines?

Tumors present an unique challenge to the immune response, and it is difficult to develop therapies to focus the power of the immune system towards eliminating tumors. This solution details what we know about the challenges in developing vaccines against tumors.

How the immune system recognizes pathogens

Most biologists believe that the immune system's defense against infections largely rests on its ability to distinguish self molecules from non-self molecules. This concept seems central to our understanding of immune function. Several immunologists developed an alternative hypothesis: that the immune system's effectiveness re

Effect of antigen exposure on B cell response

This solution is an interpretation of an experiment that measures hapten-specific B cell response by limiting dilution assay. The explanation begins with a brief background on antigen-antibody response and the limiting dilution method to evaluate it. The effect of pre-exposure to hapten and the generation of hapten-specific B ce

Immunology experiment telling what types of molecules

An experiment that used syngeneic mice that had been immunized with ovalbumin. Experimental group: Dendritic cells were fed ovalbumin four hours prior to mixing splenic CD3+ and CD4+ mixed together (control group splenic CD3+ and CD4+ only). An hour after the cells had been mixed together they were lysed and immunoprecipitati


See attached file for full problem description. Table 1: Affinities of tg ARS antibodies It is possible to make transgenic (tg) mice whose B cells ___________________________________ express a tg heavy chain gene. An investigator recently Antibody Ka did an intriguing experiment to probe the basis for ___________________


What is a theory (somatic mutation model) supposed to accomplish? What is the purpose of competing theories? When can you discard a theory? What constitutes "success?" These are obviously philosophical questions, and scientific philosophers have puzzled over them quite a bit. So my challenge to you this week is to address those

Immunology Response Progress

As humoral responses progress, the average affinity of the antibodies produced rises, in a process known as "affinity maturation." This seems at odds with at least one aspect of the clonal selection hypothesis, since the notion of "clonal integrity" implies that the progeny of an activated lymphocyte retain the specificity the o


1. A researcher purified mu heavy chains from two inbred* strains, called C3H and A/J. She immunized mice from each strain with the other's mu chains, yielding C3H anti-A/J mu and A/J anti-C3H mu. She tested each antiserum against normal serum immunoglobulins from the sources shown: Precipitate with serum from: Antiserum C


Here is a problem: Go to this or other histology links you might find: These all have either cartoons and/or histology sections of all the important primary and secondary lymphoid organs that we talked about. Click through their sections, readings, and animation

Antibiotics in Animal Feed

The use of antibiotics in animals is a very controversial issue. Do you feel that it is a bad idea to use antibiotics in animal feed or do you feel that the public is overreacting? Discuss the opposing view also. Choose a side and defend it.

Flu - vomiting - blood pH

While visiting your family, you come down with a severe case of stomach flu. You begin vomiting and continue vomiting for more than a day, unable to keep any food or fluids down. How would you expect your condition to affect your blood pH and why would this change occur? How would it affect your urine pH and why would this chang