HIV & IMMUNE SYSTEM
Table of Contents
HISTORY .................................................................................................................................................... 1
WHAT IS A VIRUS .................................................................................................................................. 1
FUNCTIONING OF HEALTHY IMNMUNE SYSTEM ..................................................................... 1
Uniqueness of HIV ........................................................................................................................... 2
AIDS = acquired Immune Deficiency 5. HIV2 – West Africa 1986; Not so
Syndrome pathogenic.
6. HIV1 – 1983 – Dr Luc Montagnier
HISTORY
fm Louis Pasteur Institute Parks
1. 1981
1984 – Dr Robert Gallo – USA –
2. 1983 virus induced
a) Propogate virus in cell strc
3. 1986 HIV
b)
4. HIV1- Central, East Southern Africa,
Dev. 1st diagnostic test 4 HIV
North & South America, EU, rest of
world.
chapter 2 – HIV & Immune system
8. HIV has 3rd part = lipid envelope
WHAT IS A VIRUS
9. Viruses only attack specific cells
1. Pathogen
10. HIV ID by cone shaped core
2. Smallest
11. Main protein of HIV p.24
3. Parasitic
12. HIV Hijacks CD4 cells, immune
4. Genes with master code
defence cells
5. DNA core
6. HIV = RNA FUNCTIONING OF HEALTHY IMMUNE
7. 2 Main parts = core = DNA/RNA SYSTEM
1. Non-specific - Barriers (skin)
Capsule = protects core
Inflammatory reaction
Proteins, projections (spikes)
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,Protective proteins (attract phagocytes, c. Send chemical messages to T & B
devour microbes) Lymphocytes to make antibodies
2. Specific - T Lymphocytes – CD4 3. Attack & Victory
enhance others response a. T cells – killer T inject infected cells
Suppressor T Lymphocytes – CD8 & contents spill out
proteins b. Antibodies attach to cell
Killer T Lymphocytes (Cytotoxic T c. Slows virus &
Lymphocytes) – directly binds with phagocytes/macrophages consume
enemy them
Memory T Lymphocytes d. Antibodies kill with chemicals
B Lymphocytes – Plasma B Lymphocytes 4. Cessation of Hostility & Recording
( produce antibodies) of info
Memory B Lymphocytes – Work on T a. Suppressor T Cells tell B cells to
cell command stop
3. Soldiers – 3 Regiments b. Memory T & B Cells remember
a. Phagocytes antigen
b. T Lymphocytes 5. Effect of HIV on immune system
c. B Lymphocytes a. Attacks CD4 cells directly
4. Four phases b. Hijacks cell. P.19
1. Enemy recognised – battle begins 6. Vaccines
a. Phagocytes = spies a. Genetic engineering
b. Can’t kill organic enemy b. Protein based tech
c. Call Macrophages which mobilise c. Humoral response – Antibody
lymphocytes production
d. By capturing enemy antigen & d. Cellular response – WBC
displaying it production
e. Antigen alerts T Lymphocytes e. Initial aim: Reduce
f. T Lymphocytes (CD4) recognise susceptibility
antigen & with macrophage go to Reduce progression
next phase Reduce Infectiousness
2. Forces multiply
Uniqueness of HIV
a. CD4 multiply
• HIV = retrovirus & roughly circular in
b. Activate more phagocytes
shape.
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,• Ver small organism & each particle =
0.0001mm in diameter – electron
microscope.
• Core = cone shaped.
• Core houses genetic material &
several proteins (enzymes).
• Viral enzymes (reverse transcriptase
enzyme, protease enzyme &
integrase enzyme) help copy virus
inside host cell & during infection,
injected with viral genetic material
into host cell.
• Viral enzymes = main targets for
ARV treatment.
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, chapter 3
Transmission of HIV
TABLE OF CONTENTS
SEXUAL TRANSMISSION .................................................................................................................... 1
MICROBICIDE........................................................................................................................................... 1
TRANSMITTING THROUGH CONTAMINATED BLOOD ............................................................. 1
MOTHER-TO-CHILD TRANSMISSION (MTCT)................................................................................ 1
TRANSMISSION OF HIV IN CHILDREN .......................................................................................... 2
POVERTY & DEPRESSED SOCIO-ECONOMIC CONDITIONS AS FACTORS
CONTRIBUTING TO SPREAD OF HIV INFECTION ................................................................ 2
MYTHS ABOUT TRANSMISSION (NOT TRANSMITTED BY): ................................................... 2
SEXUAL TRANSMISSION MOTHER-TO-CHILD TRANSMISSION
Women longer exposure to semen. (MTCT)
Major cause of kid infection.
Higher concentration of HIV in
Via placenta – pregnancy
semen.
Via blood – childbirth
Menstruation.
Breastfeeding
Young & old women more
Reduced during pregnancy if:
vulnerable.
i. No new infection
MICROBICIDE ii. Prevent/treat STI
Kills microscopic organism. iii. Nutritional supplements
Condoms more effective. iv. Prophylactic antibiotic treatment
v. Monitor mothers’ health
TRANSMITTING THROUGH
CONTAMINATED BLOOD vi. Monitor fetus
Transfusions & blood products. vii. Counsel safe sex
Injecting drug users. Reduce during childbirth:
Blood contaminated needles, i. Antiretroviral therapy
syringes & sharp instruments. ii. Disinfect birth canal
iii. Avoid unnecessary membrane
rupture
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