Immune Response, Toxins, & Nutrition

Immune Response to Microorganisms

Immune system – the body system that protects against pathogens and cancer

Immunity – the ability to resist disease

The immune system has 3 lines of defense:

Immune Response

1st line of defense (nonspecific): skin, ciliated cells, mucus membranes – act as barriers and traps

Immune Response2nd line of defense (nonspecific): increased body temperature

(fever) to create conditions unsuitable for pathogen growth; increased blood flow to injured or infected site resulting in inflammation; blood brings white blood cells called macrophages that engulf and kill pathogens

Immune Response

3rd line of defense (specific): macrophages activate helper T cells that (1) activate other T cells that destroy infected cells and (2) activate B-cells to make antibodies; antibodies attach to pathogens, clumps them, and signals them for destruction.

Passive vs. Active Immunity

Active Immunity – body’s own immune response is activated and produces antibodies; occurs when a pathogen or a vaccination is introduced into the body; long-term effect; once you get exposed to pathogen, you retain those antibodies for awhile, explaining why some diseases are only contracted once in a lifetime

Active Immunity

Memory B cells keep antibodies “on file” in case of future exposure to antigen

Passive vs. Active Immunity

Passive Immunity – antibodies are introduced into the body (not a result of immune system response); example – mother transfers her immunity to infant during breast-feeding; effects are short-term

Vaccines

• Made from weakened pathogens, pathogen parts, dead pathogens

• Injections, nasal sprays, ingested• Causes body to make antibodies that can be

used if it is exposed to the “real deal”; will shorten or prevent illness

• There are risk factors – allergic reactions, actually getting disease from vaccine, etc.

Vaccines now available for:

Toxins

Effects of Environmental Toxins

Toxin – poisonous substance that can cause disease– Symptoms depend on dose, how long you’ve

been exposed, the way it got in the body, and body response.

Effects of Environmental Toxins

1. Mercury– Sensory impairment (vision, hearing, speech), lack of

coordination, disturbance in sensations (pins and needles), muscle weakness, skin rash, mood swings, memory loss, mental disturbance

– Damage to central nervous system, liver, digestive tract, kidneys, prolonged exposure leads to brain damage and death

– Major sources – ingestion of contaminated food (mainly fish) and water, air pollution, improper use of items such as thermometers and fluorescent light bulbs

Mercury

From 1932 to 1968, the Chisso Corp. dumped nearly 27 tons of mercury waste into Minamata bay, Japan. In the mid-1950’s, a strange disease emerged that seemed to affect cats, birds, and people.http://science.education.nih.gov/supplements/nih2/chemicals/activities/lesson5.htm or http://aileenarchive.or.jp/minamata_en/slides/swf.html

Effects of Environmental Toxins2. Lead

– Major sources – lead paint (1978), toys, lead bullets, sinkers, plumbing, air (when we used leaded gas), pewter

– Symptoms:• Child: irritability, weight loss, sluggishness,

abdominal pain• Adult: pain/tingling in the extremities, muscle

weakness, headache, abdominal pain, memory loss, mood disorders, reduced sperm count, abnormal sperm

Lead

Lead Paint chips

Nutrition

Nutrition1. Good Nutrition – can maintain good health and

prevent disease– Nutrients are substances the body needs to obtain

energy and build and replace tissue• Carbohydrates – energy

• Fats – store energy, insulation, building cell membranes

• Proteins – chemical reactions, body structure, traits

• Vitamins – naturally occurs in plant and animals; help body with specific functions

• Minerals – not made by living things (ex. Calcium, iron)

– Good nutrition is a balance of all of the above

Nutrition2. Bad Nutrition – can

lead to:– Obesity – the wrong

amounts of sugars/carbohydrates and fats coupled with lack of or too little exercise; also has genetic component; can lead to other complications such as diabetes

Nutrition– Malnutrition – an

overall deficiency of most or all the nutrients; can lead to other complications including decreased immunity

Malnourished child with dysentery

Nutrition– Specific deficiencies – not

enough of certain vitamins and minerals can lead to specific health problems

Examples:Scurvy – deficiency of

Vitamin C; causes inflammation of the tongue, spongy gums, blue and black spots on skin, sunken eyes, pallor, corkscrew hair, nosebleeds; was common among sailors

Nutrition

Goiters – deficiency of iodine; causes swelling of the thyroid gland (in your neck), tight feeling in your throat, coughing, trouble swallowing and breathing; not a problem in U.S. since iodized salt.

Nutrition

Osteoporosis – disease caused by lack of enough calcium in the diet over many years; causes brittle bones, and hunched/stooped over appearance.

For more about vitamin & mineral needs/deficiencies: http://www.changingshape.com/resources/references/vmchart.asp