Immune System Aubrey Menchaca P : 5

Major functions of the lymphatic & immune system

Location of lymphatic organs and their functions

Purpose and examples of First, Second, and Third line of defense

Innate ( natural ) immune defense and Adaptive ( acquired ) immune defenses

Humoral response and cellular response

Antigens and antibodies

Artificial vs. Naturally acquired immunity

Passive vs. Active immunity

Cells involved in the Immune system and their functions

Disorders associated with the Immune system

First line

Second line

Third line

Innate defense system

Adaptive immune system

First line - external body membranes

Second line - antimicrobial proteins, phagocytes, and other cells

Constitutes first and second lines of defense

Functional system rather than organ system

T and B cells

Third line of defense attacks particular foreign substances

Both

defenses are interwined

release and recognize many of the same defensive molecules

Innate response release proteins that alert cells of adaptive system to foreign molecules

Physical barrier to most microorganisms

Purpose is to produce productive chemicals that inhibit or destroy microorganisms

Surface barriers are skin and mucous membranes, along with secretions

Respiratory system also has modifications to stop pathogens

Includes - phagocytes, Natural killer cells, Inflammatory response, fever, Antimicrobial proteins

Many have pattern recognition receptors that recognize and bind tightly to structures on microbes, disarming them before they harm

Innate system necessary if microorganisms invade deeper tissues

Immune cells target specific antigens

Defenses are known as B cells and T cells also known as white blood cells

B cells produce antibodies while T cells help identify pathogenic cells and destroy the specific cells

Active

Passive

Humoral

Cellular

When B cell encounters target antigen, it provokes a response

Specific antibodies are produced for particular antigen

Antibodies, produced by lymphocytes, circulate freely in body fluids

Ex : cells infected with viruses or bacteria, cancerous or abnormal cells, foreign transplanted cells

Some T cells directly kill cells ; others release chemicals that regulate immune response

T cells provide defense against intracellular antigens

primary and secondary responses

Primary - responds to antigen A occurs after a delay

Secondary - responds to antigen A is faster and larger ; primary is similar to A

Two types of active humoral immunity

B cells encounter antigens and produce specific antibodies against them

Naturally acquired - formed response for bacterial or viral infection

Artificially acquired - formed response to vaccine of dead pathogens

Ready-made antibodies are introduced into the body

B cells are not challenged by antigens ; immunological memory wont occur

Two types of passive humoral immunity

Protections ends leading to antibodies degrading

Naturally acquired - delivered to fetus through placenta or through milk

Artificially acquired - serum such as gamma globulin

Through humoral immunity and is categorized from active and passive

Active

Passive

Naturally acquired - Antibodies passed from mother to fetus via placenta ; or to infant in milk

Artificially acquired - injection of exogenous antibodies ( gamma globulin )

Artificially acquired - Vaccine ; dead or attenuated pathogens

Naturally acquired - infection ; contact with pathogen

Two populations of T cells

CD4 cells - become helper T cells which activate B cells

CD8 cells - become cytotoxic cells that are capable of destroying cells harboring foreign antigens

Maintains fluids and balance

absorb dietary fats from gastrointestinal tract

Provides resistance to disease

Natural killer cells -Nonphagocytic, large granular lymphocytes that police blood and lymph

Can kill cancer and virus infected cells before adaptive immune system is activated

Kill by inducing apoptosis in cancer or virus cells

Phagocytes - White blood cells that ingest and digest

Neutrophils - most abundant phagocytes but die fighting

Macrophages - develop from monocytes and are chief phagocytes

Lymphocytes

T cells - cellular immunity

B cells - humoral immunity

Dendritic cells - Act as mobile sentinels of boundary tissues found in epidermis and connective tissues

Hepatitis B - Disease that is caused by virus that attacks liver

Small pox - Serious infection caused by variola virus

Cholera - An acute diarrhea illness caused by infection of the intestine

Meningitis - infection / inflammation of fluid and membranes surrounding brain and spinal cord

Rubella - Viral infection caused by RVV

Malaria - Disease caused by bites of infected mosquitos

Chicken pox - Highly contagious disease caused by varicella

Tetanus - serious viral infection

Antigens

Antibodies

Substances that can mobilize adaptive defenses and provoke an immune response

Targets of all adaptive immune response

Most are large, complex molecules not normally found in body

Proteins secreted by plasma cells

Capable of binding specifically with antigen detected by B cells

Grouped into one of five Ig classes

Thymus - produces immune cells and in between lungs

Peyer's patch - located in small intestine and protects digestive system

Spleen - fights against infecting blood cells and located under stomach

Red bone Marrow - In flat bone where it contains the T and B cells

Tonsils - Protect germs from entering body and fight against infection. located in the back of mouth

Fights against pathogens