IMMUNITY

BLOOD CLOTTING

• Non-specific defense – seals wound and prevents blood loss• Platelets form a temporary

plug• Release clotting factors• Prothrombin is converted to

thrombin (calcium and vitamin K needed)

• Thrombin converts soluble fibrinogen to fibrin

• Fibrin forms a mesh and traps more platelets

ACTIVE AND PASSIVE IMMUNITY

• Active immunity – antibodies produced inside the body • Passive immunity –

antibodies acquired from outside the body• Babies: from breast milk• Injected into rabies and

anthrax patients

MONOCLONAL ANTIBODIES

• Specific, purified antibodies• Only recognize one antigen

1. Inject antigen into a mouse2. Extract plasma B-cells from spleen3. Fuse B-cell with cancer cell (hybridoma)4. Screen for antibody you want5. Culture to make antibodies in bulk

• Used to treat and screen for diseases• Pregnancy tests

W H E R E P O L I T I C S , M E D I C I N E , A N D S O C I E T Y M E R G E

HIV & AIDS

HUMAN IMMUNODEFICIENCY VIRUS

•Retrovirus (contains RNA, not DNA)• Reverse transcriptase (enzyme)

converts RNA to DNA

• The host cell for HIV is the T-helper cell• B cell activation never takes place

which means NO antibodies

HUMAN IMMUNODEFICIENCY VIRUS

• A very “smart” virus—surface proteins mutate often• These are what

antibodies would recognize, so on the outside HIV is literally creating a whole new virus

HUMAN IMMUNODEFICIENCY VIRUS

• Infection can go on for years before actual AIDS symptoms appear• all characterized by T cell count

• With effectively NO immune system, full blown AIDS makes patients prone to opportunistic illness

HUMAN IMMUNODEFICIENCY VIRUS

HUMAN IMMUNODEFICIENCY VIRUS

• 34 million people estimated to be living with HIV/AIDS worldwide• 3.4 million children

• 1.8 million people per year die of AIDS complications• ~30 million to date

• In US was thought to be a disease which afflicted only gay men and IV drug users

• Main sources of infection are though body fluids (blood, vaginal secretions, semen, breast milk, and across the placenta)• Blood transfusions • Dirty needles, unprotected sex

HUMAN IMMUNODEFICIENCY VIRUS

• Blood samples from several African nations have shown HIV as far back as 1959 • First diagnosed in the U.S. in 1981, virus first

identified in 1984 by two scientists (in France & the U.S.)• Researchers believe virus mutated from 2 simian

viruses (monkey/chimps) when people in the 1930s would eat chimp meat in the bush in the Democratic Republic of Congo• The U.S. story is one of political strife,

discrimination, and medical ingenuity

HUMAN IMMUNODEFICIENCY VIRUS

• Because HIV infections in the U.S. were first only linked to gay men and IV drug users, it wasn’t politically popular to fund its research

• It was well known and accepted, even by late 1981, that there was a serious epidemic taking place

• Hemophiliacs receive treatments made of human blood products

• In the early 1980s these blood products were not screened for infectious diseases

• Enter Ryan White—a teenage boy who faced massive, unwarranted discrimination, captured the attention of the nation, and led to the minimal acceptance of AIDS being worthy of government funding

HUMAN IMMUNODEFICIENCY VIRUS

• Ryan was a teenager in Indiana, who was a hemophiliac• He was diagnosed in 1984 with full-blown AIDS at

13• Some examples of the discrimination he faced:• Western School Corp. Superintendent James O. Smith

denies Ryan admission to Western Middle School in Kokomo

• Parents of Kokomo school children sign 117 claim forms threatening a civil suit if Ryan is allowed to enter school

• About 50 teachers vote to support the decision to keep Ryan out of school

HUMAN IMMUNODEFICIENCY VIRUS

• Some examples of the discrimination he faced:• Ryan returns to school for the first time in 14 months, but 151 of 360

students stay home and seven transfer to other schools. • The Concerned Citizens and Parents of Western School, along with

Dick Bronson, a local radio personality, host an auction at Western Middle School gymnasium to raise money to keep Ryan out of school.

• A home school opens in Russiaville, IN, for students whose parents don't want them to attend school with Ryan.

• Ryan eventually moved, a became a national celebrity/poster child for HIV

• He befriend Elton John, Michael Jackson, and numerous other celebrities

• Ryan died in 1990 @ 18, his funeral was aired live by all major networks

HUMAN IMMUNODEFICIENCY VIRUS

• HIV/AIDS is affecting the world in many different ways• One thing remains the same—it is a killer, it is easily

spread, and it is expensive to treat• Some statistics:

HIV is one of the world's leading infectious killers, claiming more than 25 million lives over the past three decadesThere were approximately 34 million people living with HIV in 2010~1.2 million adults (15-49) in the U.S. living with AIDS (.6%)~190,000 adults in Swaziland, Africa living with AIDS (25%)

HUMAN IMMUNODEFICIENCY VIRUS

• African Americans in the United States make up 13% of the population but they make up 51% of AIDS cases (2007)

• Southern African nations have a grossly disproportionate rate of infections

• What social and political issues may lead to these discrepancies?

• How has this pandemic become an issue of global concern?

• What cultural/behavorial issues may exist that put certain countries at higher risk?

• What moral obligations do countries like ours have in curbing the impact of HIV infections world-wide?