Think about the last time you cut yourself. Once the bleeding stopped, what did you notice about the area

where the tissue had been damaged?

Second – line defense: Inflammatory Response

•Increase of blood supply to affected area• Redness, swelling, heat

•Chemicals released from injured tissue leads to an increase in macrophages• Ingest bacteria and any damaged tissue

http://www.bluebananadesigns.com/images/illustration/medium/macrophageAttacksMed.jpg

Third Line of Defense – Immune System

•Specific Response

•Antigen (antibody generator)– any substance that causes an immune response

•Lymphocytes – cells of the immune system • recognize specific antigens

B lymphocytes (B cells) or T lymphocytes (T cells)

•either attack directly or create antibodies (proteins that fight antigens)

T Cells•Produced in bone marrow

•Develop in thymus (gland)

http://www.med.uio.no/imb/anatomi/immunobiolab/research-groups/rolstad/publications/2009/BoneMarrow.gif

Helper T Cells•Primary Task – activate B cells and killer T cells

•Helper T cells activated by macrophage• Macrophage ingests invader and displays invader’s

antigen on its surface

Helper T-Cell•A helper T-cell is activated when its receptor recognizes the antigen•T cells divide and produce proteins to activate B cells and other T cells

Killer (Cytotoxic) T Cells•Attack and kill cells infected with pathogen

•Receptors search each cell for antigens• If a cell is infected, it is killed

B Cells•Searches for antigen matching its receptor• If a match is found, helper T cells help B cells to

divide into two versions

B Plasma Cell B Memory Cell

B Plasma Cell•Produce antibodies

B Memory Cell•Prolonged lifespan and can “remember” specific intruders

•B memory cells (and T memory cells) activate the immune system the next time the intruder returns

Immunity has been achieved!

Organs of the Immune System

Bone Marrow

http://www.med.uio.no/imb/anatomi/immunobiolab/research-groups/rolstad/publications/2009/BoneMarrow.gif

Produces B cells and immature T cells

Thymus

•From Greek “thymos” : warty growth

•Produce mature T cells

Spleen (the immunological conference center)

http://www.nlm.nih.gov/medlineplus/ency/presentations/100040_1.htm

•Captures antigens from blood that pass through by way of migratory macrophages•B cells are activated and antibodies produced

•Old red blood cells are destroyed

•Immune response is initiated

Lymph Nodes•Located throughout the body

•Drain and filter fluid from our body tissues

•Antigens filtered out before liquid is returned to circulation

Diseases of Immune System

Allergies•What Happens in Body

Excessive activation of certain white blood cells resulting in an extreme inflammatory response

•Symptoms

Include itchiness, runny nose, rash, anaphylactic reactions and potentially death

•Relation to Immune System

Involves white blood cells

Allergies•Develop disease

Develops post-fetally. Can be caused by heredity or environment.

•Treatment

Avoiding or reducing allergen. Drugs including antihistamines, cortisone, epinephrine (epi-pen)

Allergies

Asthma•What Happens in Body

Airways can constrict, become inflamed, and are lined with excessive amounts of mucus.

Asthma•Symptoms

Chronic respiratory impairment or brief episodes that may result from a number of triggering events. Shortness of breath, wheezing, coughing.

•Relation to Immune System

Antigens trigger respiratory system responses

AsthmaCommon asthma triggers include:• Animals (pet hair or dander)

• Dust• Changes in weather (most often cold weather)

• Chemicals in the air or in food• Exercise• Mold• Pollen

• Respiratory infections, such as the common cold• Strong emotions (stress)

• Tobacco smoke

Asthma•Developing Disease

Genetic and environmental factors (poor air quality, exposure to cigarette smoke, etc)

•Treatment

1. Long-term medications to prevent attacks2. Quick relief medications during attacks

AsthmaShort-acting bronchodilator (inhaler)

Pressurized canister of aerosol medication that relaxes muscles in airways

Lupus•What Happens in Body

Immune system cannot tell the difference between foreign substances and its own cells and tissues. Makes antibodies directed against itself. These "auto-antibodies” cause inflammation, pain and damage in various parts of the body.

•SymptomsPain, heat, redness, swelling and loss of function either on the inside or on the outside of the body (or both), achy joints, prolonged/extreme fatigue, skin rashes

Lupus

•Relation to Immune System

Body produces antibodies against itself

•How does one develop disease

Genetic and environment (antibiotics, ultraviolet light, extreme stress, certain drugs, and hormones)

Lupus•Treatment

Medications to reduce inflammation which causes pain, fever and swelling, and other medications to suppress the overactive immune system.

HIV/AIDSHIV

umanmmunodeficiencyirus

AIDS

cquiredmmunoeficiencyyndrome

HIV/AIDS•What Happens in the Body

T cells in the body are destroyed – used to replicate virusHIV is considered to be AIDS when the immune system is too weak to fight off infections

•Symptoms•Flu-like illness 2-6 weeks after infection. •Next stage - swollen lymph nodes, diarrhea , weight loss, fever, cough and shortness of breath. •AIDS - Soaking night sweats, Shaking chills or fever higher than 100 F for several weeks, dry cough and shortness of breath , chronic diarrhea, persistent white spots or unusual lesions on tongue or in mouth, headaches, blurred and distorted vision, weight loss

HIV/AIDS•Relation to Immune System

T cells are reduced

•Developing Disease

Transmitted from person to person through the exchange of bodily fluids

HIV/AIDS•Treatment

No cure – antiviral drugs suppress viral replication

Drugs include Saquinavir, Ritonavir, Indinavir and Nelfinavir