Immune System

Types of inflammation?

Acute/ Chronic

Types of Allergies?

Airborne Food Atopic dermatitis Atopic induced asthma

What diminish allergy symptoms by blocking receptors for histamine??

Antihistamines

T-Cells

Attack against cancer

Inflammation can predict?

Etiology of malnutrition

Factors associated with increased inflammatory markers

Lack of sleep Increased belly fat Arachadonic acid

Reasons Allergies May Contaminate Food?

Same utensils Same equipment Misleading labels Processing

70 % of Immune System is form?

Skin

What provides first line barriers to infections?

The skin

Adverse Food Reaction?

any undesired response to a food

Innate defenses are largely nonspecific, responding to a broad range of microbes that are?

physical, chemical or microbiological barriers.

Inflammatory Response

Histamine causes vasodilation and influx of cells and other chemicals to fight the challenge -Increase blood flow resulting in heat and redness Histamine increase capillary permeability so plasma proteins can leave the blood -Vascular permeability resulting in swelling and pain Inflammatory mediators include histamine, prostaglandins, luekotrienes, interferon, kinins, and cytokines.

One of the chemical signals of the inflammatory response?

Histamine, which is stored in mast cells in connective tissues. When injured these cells release histamine. triggering dilation and increased permeability of nearby capillaries.

Symptoms of milk allergies in kids?

Hives and itching (skin) Wheezing Coughing Severe nasal symptoms (respiratory tract) Vomiting and/or diarrhea (gastrointestinal tract)

Iron Deficiency?

Homebound but fairly healthy elderly women in Canada • Some had low Fe status, some didn't • Immune functions measured using cells isolated from the blood • Immune functions were lower in the Fe deficient women

2 Types of Adaptive Immunity

Humoral (Antibody-mediated immunity) Cell-mediated immunity

Most common antibodies involve those of ?

IgE class

Vitamin A deficiency?

Immpairs immune functions and increases susceptibility to infection.

Preventative Measures for Allergies?

In high-risk infants Mother should breast-feed and avoid typically allergenic foods. Wait until 2 to 3 yrs of age to introduce milk, egg, peanuts, fish. Controversy: Wait or Induce?

Note:

Increased local blood supply leads to the characteristic swelling, redness, and heat of inflammation. Blood-engorged leak fluid into neighboring tissue, causing swelling.

Is Inflammation is a synonym for infection?

Infection is caused by a microorganism, while inflammation is one of the responses of the organism to that infection.

Part of Non-Specific Immunity?

Inflammation

Purpose of Inflammation?

Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process. The purpose is to prevent the spread of injurious agents, dispose of pathogens and dead cells, and set the stage for repair.

Is Inflammation part of specific or non-specific immunity?

Inflammation is usually a stereotyped response, and therefore it is considered as a mechanism of innate or non-specific immunity, as compared to adaptive immunity, which involves antibodies and is specific for each pathogen.

3 Lines of Defense?

Innate External defenses (Surface barriers) are the first line of defense - non-specific. Innate Internal defenses are the second line of defense - non-specific. Adaptive defenses are the third line of defense - specific.

Second line of defense?

Innate Internal Defense

Innate Internal Defenses?

Innate internal defenses identify enemies by recognizing a limited number of markers unique to pathogens. They attack immediately. When innate defense cells are overwhelmed, they secrete chemical messengers to mobilize adaptive defenses. Also non-specific immunity

Humoral Immunity?

1. Antibodies that are found in the plasma are produced by B lymphocytes, also known as B cells, in response to exposure to various types of foreign substances. They form the basis of antibody-mediated immunity. 2. Classes of antibodies - IgG, IgM, IgA, IgE, and IgD. i. IgG comprises 80% to 85% of total serum antibody and is responsible for numerous actions, including Rh reactions such as erythroblastosis fetalis, in which a pregnant mother with Rh negative blood is exposed to Rh positive fetal blood late in the pregnancy or during delivery and produces antibodies to Rh antigens that may enter the fetal circulation and destroy the fetus' red blood cells. Erythroblastosis fetalis is potentially fatal to the fetus. ii. IgM is responsible for transfusion reactions in the ABO blood system. It often is the first antibody produced in response to a foreign antigen. iii. IgA is present in saliva, tears, and on mucous membranes. High concentrations of IgA are present in breast milk and provide significant immune protection to the newborn infant. iv. IgD is located on the cell membranes of B cells and acts as an antigen-binding site. v. IgE comprises only .002% of total serum antibody but is responsible for nearly all allergic reactions. Recent information suggests that IgE also plays a significant role in the development of asthma.

Inflammation can be classified as?

Acute or chronic

Allergies are hypersensitive (exaggerated) responses to certain environmental antigens, called ?

Allergens

anaphylactic shock

Anaphylactic shock results when widespread mast cell degranulation triggers abrupt dilation of peripheral blood vessels, causing a precipitous drop in blood pressure. Death may occur within minutes. Triggers of anaphylactic shock in susceptible individuals include bee venom, penicillin, or foods such as peanuts or fish. Some hypersensitive individuals carry syringes with epinephrine, which counteracts this allergic response.

Immune System over Life

Babies are born with an immature immune system -> this will develop over time with increasing exposure to new antigens (i.e. to new foods and to new pathogens) • The function of the immune system declines with old age (depletion of natïve cells due to cumulative lifetime antigen exposure?)

Cell- Mediated Immunity?

Can cause Delayaed responses. 1. Achieved by the actions of T lymphocytes, or T cells. 2. T effector cells - Carry out most cell-mediated immune functions, seeking and destroying foreign materials such as viruses, fungi, bacteria, and particles. 3. T helper cells - Aid the T effector cell's actions. 4. T suppressor cells - Limit the specific immune response. 5. When activated by an antigen, T cells differentiate into T memory cells and T effector cells. i. T memory cells remain within the body, ready to respond to a second challenge. ii. T effector cells produce lymphokines, complex proteins that recruit mast cells and other nonspecific inflammatory mediators to aid in destruction of the antigen. iii. T effector cells bind to the foreign cell and cause it to break apart, a process known as lysis. These specialized T effector cells often are called killer T lymphocytes.

What is the Immune System?

Cells , molecules, tissues, and organs that function to protect the body from foreign invaders are collectively known as the immune system; Integrally related to the lymphatic system.

Inflammation Explained

Certain bacterial infections can induce an overwhelming systemic inflammatory response leading to a condition known as septic shock. Characterized by high fever and low blood pressure, septic shock is the most common cause of death in U.S. critical care units. Clearly, while local inflammation is an essential step toward healing, widespread inflammation can be devastating.

About Adaptive Immunity

Compared to the innate response, adaptive immunity is much more complex because it involves antigen-specific responses. Exposure to a specific antigen on an invading pathogen stimulates production of immune cells that target the pathogen for destruction; subsequent responses to the same pathogen are stronger and more efficient because the antigen is "remembered." The major mediators of the adaptive immune response are specialized white blood cells, namely B lymphocytes (B cells) and T lymphocytes (T cells). Although the innate and adaptive immune systems have unique functions, their components interact and work together to protect the body from infection and disease.

If the innate response doesn't work the adaptive immunity is summoned through the signaling of what messenger protein?

Cytokines

Anaphylaxis?

Fatal immune response Peanuts and tree nuts

Lymph Nodes?

Filter lymph fluid Occur in clusters 2 functions -Defense -White blood cell formation

Decrease inflammatory markers?

Fish oil Vitamin K

Role of lymphatic system in fluid homeostasis.

Fluid from blood plasma that is not reabsorbed by blood vessels drains into lymphatic vessels. Lymphatic drainage prevents accumulation of too much tissue fluid.

Humoral (Antibody-Mediated) Immunity Categories

Genetic or natural passive immunity results when antibodies from the mother cross the placental barrier to provide protection against fetal infections We are born with natural immunity Acquired immunity Artificial immunity Another Example: A pregnant mother with Rh negative blood is exposed to Rh positive fetal blood late in the pregnancy or during delivery and produces antibodies to Rh antigens. Now these antibodies may enter the fetal circulation and destroy the fetus' red blood cells.

What does the Immune System Do?

Gives you the ability to resist damage from foreign substances or harmful chemicals. Destroys pathogens - organism that causes disease Ex viruses, bacteria, protozoa, fungi, parasitic worms Detects and kills abnormal cells (cancer) Removes dead cells Provides both specific and non-specific immunity

Risk for Development of Food Allergy?

Heredity Exposure to a food (antigen) Gastrointestinal permeability Amount of antigen plus environmental factors

Note:

Intact skin is a barrier that cannot normally be penetrated by bacteria or viruses, although even minute abrasions may allow their passage. Likewise, the mucous membranes that line the digestive, respiratory, and genitourinary tracts bar the entry of potentially harmful microbes. Cells of these mucous membranes produce mucus, a viscous fluid that traps microbes and other particles. In the trachea, ciliated epithelial cells sweep out mucus with its trapped microbes, preventing them from entering the lungs. Beyond their role as a physical barrier, the skin and mucous membranes counter pathogens with chemical defenses. In humans, for example, secretions from sebaceous and sweat glands give the skin a pH ranging from 3 to 5, which is acidic enough to prevent colonization by many microbes. Microbes present in food or water, or those in swallowed mucus, must contend with the highly acidic environment of the stomach. The acid destroys many microbes before they can enter the intestinal tract. One exception, the virus hepatitis A, can survive gastric acidity and gain access to the body via the digestive tract. Hep A spreads by the fecal-oral route; transmitted person-to-person by ingestion of contaminated food or water or through direct contact with an infectious person. Microbial colonization is also inhibited by the washing action of saliva, tears, and mucous secretions that continually bathe the exposed epithelium. All these secretions contain antimicrobial proteins. One of these, the enzyme lysozyme, digests the cell walls of many bacteria, destroying them.

Specific- Cellular Immunity?

Involves phagocytosis by T cells and macrophages. Directed primarily against intracellular pathogens and cancerous cells.

Appropriate nutrient supply = Appropriate nutrient status (& stores)= Appropriate immune function= Better defense against pathogens

Just Info

Immune System has two Anatomical Parts

Leukocytes Lymphocytes All cells of the immune system originate in the bone marrow but the ones pertaining to the lymphatic system mature in the lymphoid organs

Immune system cells that travel in the blood ?

Leukocytes ( WBC)

Lymphatic System Components?

Lymph fluid Lymph nodes Lymph vessels Lymphoid organs

How do you measure immune function?

Measure immune markers in blood or other accessible sites (e.g. there are certain antibodies in saliva) • Isolate immune cells from blood and then study those cells in culture -> can measure functional response

List of Specialized Immune Cells and Defined?

Neutrophil - phagocytize pathogens Monocyte - (become macrophages) phagocytize pathogens Eosinophil - fight parasites Basophil release histamine and other inflammatory factors)

Specialized Immune Cells?

Originate in the bone marrow, and migrate to tissue and reside or travel thru the blood and lymphatic system and enter tissue when needed

________are non-specific but can still recognize common antigen-like markers found on pathogens

Phagocytes

5 Components of Innate Internal Defense.

Phagocytes -Neutrophils -Macrophages - secrete cytokines to alert immune system Natural Killer Cells - kill body cells infected with a virus or cancer Antimicrobial proteins - complement and interferons Inflammation Fever

Cytokines?

Phagocytes release many chemicals to mediate inflammation. They are collectively called cytokines 100 cytokines identified Work systemically and locally Cytokines commonly used as markers for inflammation -C-reactive protein -Interleukin 6 (IL-6) -Interleukin 8 (IL-8) -Interleukin-1 beta (IL-1(b) -Tumor necrosis factor (TNF)

Node Filtering Bacteria?

Phagocytic cells in node destroy bacteria

4 Cardinal Signs of Inflammation?

Redness Heat Swelling Pain possible dysfunction of the organs or tissues involved.

General Characteristics of Innate Immunity?

Relies on mechanisms that exist before infection General protection rather than against a specific threat Response time and strength does not increase with repeated exposure to the same pathogen Always ready to attack

What is the mechanism of action?

Results in the influx of cells and other chemicals that fight the foreign challenge. Many chemicals involved in the immune system promote inflammation. The most common chemicals are histamine, prostaglandins, leukotrienes, pyrogens, and interferon. These substances are produced in response to different types of infection, as well as to the presence of foreign matter. One of the chemical signals of the inflammatory response is histamine, which is stored in mast cells in connective tissues. When injured, mast cells release their histamine. Histamine triggers both dilation and increased permeability of nearby capillaries - increased blood flow can bring in more oxygen and other healing agents to the sites for repair. Histamine is derived from the decarboxylation of the amino acid histidine, an essential amino acid for children. Some forms of food poisoning are due to conversion of histidine into histamine in spoiled foodstuffs, such as fish. Histamine also acting as a neurotransmitter.

Innate External Defenses (Surface Barriers) ?

Skin and mucous membranes Nonspecific immunity - general protection rather than against a specific threat are the first line of defense. An invading microbe must penetrate the external barrier formed by the intact skin and mucous membranes, which cover the surface and line the openings of an animal's body.

Nutrients shown to improve immune response in humans?

Some amino acids - S-containing, glutamine, arginine, leucine, Taurine, and some amino acid metabolites Several fatty acids Fat-soluble vitamins - A, D, E, carotenoids Vitamin B6, folate, B12, C, ..... Zn, Cu, Se, Fe .... Flavonoids Prebiotic type saccharides

General characteristics of Adaptive Immunity?

Specific immunity. Response is specific Have memory - response to a given substance that is faster and stronger after each subsequent exposure

How does good nutrition support good immune function?

Substrates for the synthesis of chemicals involved in the immune response Regulators of aspects of the immune response (e.g. vitamin A and zinc regulate cell division)

Why learn About the Immune System in Nutrition?

The foods we eat, how nutritionally healthy and unhealthy we are, affects our ability, the immune cells' ability to fight disease. Nutrition affects our body's immune responses - poor nutrition contributes to inflammation (as in obesity) while good nutrition lessens it.

How is inflammation detected?

The inflammatory response involves countless mediators, some of which are used as clinical markers of inflammation or inflammatory diseases. C-reactive protein (CRP), an acute-phase reactant protein synthesized in the liver, is the prototypic clinical biomarker of cardiac-related inflammation and is also a general marker of inflammation. Several human diseases are inflammatory in nature, including asthma, Crohn's disease, rheumatoid arthritis, polymyalgia rheumatica, tendonitis, bursitis, laryngitis, gingivitis, gastritis, otitis, celiac disease (gluten intolerance), diverticulitis (infection of the diverticula in the colon), and inflammatory bowel disease. Additionally, a number of chronic diseases have inflammatory components, such as atherosclerosis, obesity, diabetes, cancer, and perhaps even Alzheimer's disease. The causes of several of these diseases are unknown, and the role of inflammation in disease pathogenesis is under investigation.

Innate Internal Defense In Dept?

This type of immunity depends mainly on phagocytosis, the ingestion of invading organisms by certain types of white cells or leukocytes. Phagocyte function is intimately associated with an effective inflammatory response and also with certain antimicrobial proteins. Phagocytes attach to their prey via surface receptors found on microbes but not normal body cells. After attaching to the microbe, a phagocyte engulfs it, forming a vacuole that fuses with a lysosome. Microbes are destroyed within lysosomes in two ways. Lysosomes contain nitric oxide and other toxic forms of oxygen, which act as potent antimicrobial agents. Lysozymes and other enzymes degrade mitochondrial components. Some microbes have adaptations that allow them to evade destruction by phagocytes. The outer capsule of some bacterial cells hides their surface polysaccharides and prevents phagocytes from attaching to them. Other bacteria are engulfed by phagocytes but resist digestion, growing and reproducing within the cells. TB, Leprosy, typhoid, pneumonia, chlamydia, dysentry

Leukocytes

Usually produced by the bone marrow but also the spleen; white blood cells - these are part of what we call non-specific immunity - no antibodies but just phagocytic cells that attack and digest the foreign substances.

Primary Lymphoid Organs?

Where the lymphocytes B cells and T cells mature

Food intolerance

an adverse reaction to a food caused by toxic, pharmacologic, metabolic or idiosyncratic reactions to the food or chemical substances in food that does not involve our immune system

Acute Inflammation?

as tonsilitis is the initial response of the body to harmful stimuli and is achieved by the increased movement of plasma and leukocytes from the blood into the injured tissues.

Antibodies produce humoral immunity how?

by binding to specific antigens to form antigen-antibody complexes. These complexes produce a variety of changes that inactivate or kill invading cells

Chronic Inflammation?

characterized by simultaneous destruction and healing of the tissue from the inflammatory process. In fact, tissue damage is a hallmark of chronic inflammation. In some instances, the body is unable to repair tissue damage, and the inflammatory cascade continues. Chronic inflammation is abnormal and does not benefit the body; in fact, chronic inflammation is involved in a number of disease states. Chronic inflammation is primarily mediated by monocytes and long-lived macrophages; Macrophages release several different chemical mediators, including IL-1, TNF-alpha, and prostaglandins, that perpetuate the pro-inflammatory response. Chronic inflammation can also lead to a host of diseases, such as hay fever, periodontitis, atherosclerosis, rheumatoid arthritis, and even cancer (e.g., gallbladder carcinoma). It is for that reason that inflammation is normally closely regulated by the body. Specific tissues more vulnerable to chronic inflam. Cells with little to no regenerative capacity include neurons, cardiac cells, and skeletal muscle cells. Tissues comprised of these cells would be especially vulnerable to effects of inflammation. In contrast, skin cells are labile because they continue to proliferate throughout life; thus, wounds to the skin are often easily healed.

Acquired immunity

develops in one's lifetime and is a result of exposure to invaders and antigens by the transfer of antibody or lymphocytes from an immune donor (passive immunity). Or happens by exposure and then you recover - chicken pox for instance

Artificial Immunity

exposure was deliberate such as immunization

Antigens?

foreign proteins (usually on the surface of the membrane) Aka allergens or bodies on the surface of pathogens including viruses, bacteria, and other harmful substances Antigens are usually proteins, but they can also be large carbohydrates or nucleic acids.

Note:

if the inflammation is of a mild to moderate degree, then safely predict that the malnutrition is due to a chronic illness. Now if inflammation marked, then the malnutrition could be because of some of acute trauma or injury. Overnutrition can also have the same effect. Obesity and a sedentary lifestyle can also increase body's inflammatory responses. For instance, it is known that adipose tissue secretes several inflammatory factors (adipocytokines). C-reactive protein (CRP) is a protein found in the blood, the levels of which rise in response to obesity and low pulmonary fitness. This in turn, can lead to cancers. There is evidence to suggest that calorie restriction, with or without weight loss can reduce CRP levels, and reduce risks for cancer in overwt and obese individuals.

The innate immune system is?

immediate, nonspecific response to harmful substances including pathogens. It is composed of physical barriers, such as the skin, as well as chemical and microbiological barriers, including the mucous secretions of the respiratory tract and the normal microflora of the gastrointestinal tract.

Autoimmune Disease

immune system loses tolerance for self and turns against certain molecules of the body Ex: Lupus: the immune system generates antibodies against various self-molecules, including histones and DNA released by the normal breakdown of body cells. Lupus is characterized by skin rashes, fever, arthritis, and kidney dysfunction. Rheumatoid arthritis leads to damage and painful inflammation of the cartilage and bone of joints. In insulin-dependent diabetes mellitus, the insulin-producing beta cells of the pancreas are the targets of autoimmune cytotoxic T cells. Multiple sclerosis (MS) is the most common chronic neurological disease in developed countries. In MS, T cells reactive against myelin infiltrate the central nervous system and destroy the myelin sheath that surrounds some neurons. People with MS experience a number of serious neurological abnormalities. The mechanisms that lead to autoimmunity are not fully understood. It was thought that people with autoimmune diseases had self-reactive lymphocytes that escaped elimination during their development. We now know that healthy people also have lymphocytes with the capacity to react against self, but these cells are inhibited from inducing an autoimmune reaction by several regulatory mechanisms. Autoimmune disease likely arises from some failure in immune regulation, perhaps linked with particular MHC alleles.

Inflammation?

is a biological and chemical response to harmful stimuli, such as pathogens, damaged cells, or irritants.

Food allergy

is when the immune system generates an adverse reaction to specific proteins found in food. the reaction occurs consistently after ingestion, inhalation, or touch of a particular food causing functional changes in target organs responses occur instantly or within 2 hrs of exposure - mild to life threatening. Example gluten allergy, wheat allergy

The primary components of the innate immune system ?

monocytes, macrophages, and neutrophils—immune cells that engulf and digest invading microorganisms in a process called phagocytosis.

Lymphocytes

sites that are part of the lymphatic system where lymphocytes (B cells and T cells) are produced, reside, and come in contact with pathogens - these are what we call specific immunity because they produce antibodies in response to specific antigens.

Antigen?

usually a foreign substance (e,g, protein, cells, bacteria, polysaccharides) that stimulates antibody production

Antigens can include?

viruses, bacteria, blood cells, tissue cells The surface of any given pathogen is studded with many different antigens, each usually having many different antigenic determinants.

Sensitization

xposure to an antigen or allergen that results in the development of hypersesitivity