Download Immune Response to Infectious Diseases

Immune Response to
Immune
Response to
Infectious Diseases
Zhong yiwei
20110430
Immune defense VS pathogen infection
Infectious Diseases
Infectious Diseases
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Viral Infections
Bacterial Infections
Bacterial Infections
Protozoan Diseases
Diseases Caused by Parasitic Worms (Helminths)
Immune Response to Viral Infections
Immune Response to Viral Infections
sites of infection Mechanisms of viral entry into host cells. cells
acute infections and persistent infection
Host response against acute infection
The innate immune response to viral infection
Adaptive Immune Response to Viral Infections
Viruses Can Evade Host Defense
Mechanisms
i fl
influenza virus infection i i f i
1918
1918 2009 2009
Sites of influenza entry in the respiratory tract.
The adaptive immune response during infection with influenza virus.
influenza Viruses Evaded Host Defense
Mechanisms
• The virus can change its surface antigens so completely that the immune response
• Two different mechanisms generate antigenic Two different mechanisms generate antigenic
variation in HA and NA: antigenic drift and antigenic shift.
i i hif
Antigenic shift Types of vaccine
Types of vaccine
• Inactivated virus
• Live attenuated virus
Live attenuated virus
• Recombinant subunit, DNA and vectored vaccines.
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• Universal influenza virus vaccines.
New research for influenza Each group seems to share a region of sequence conservation in the stem that can serve as a target of broadly neutralizing antibodies directed to this region.
i
Immune Response to HBV Infections
Immune Response to HBV Infections
HBV
The three main ‘pathways’ of HBv replication in HBeAg positive patients
HBeAg‐positive patients
immune response to HBV infection
p
持续性感染机制
1 病毒因素
1
病毒因素
病毒蛋白经胎盘进入胎儿体内造成机体对HBV的免疫
耐受
HBV的变异
2 机体的免疫应答因素
2 机体的免疫应答因素
固有免疫： TLR与IFN 受到抑制
获得性免疫 APC细胞不能有效的识别病毒蛋白
获得性免疫：APC细胞不能有效的识别病毒蛋白
T 细胞功能低下，treg发挥功能
Different hepatic antigen‐presenting cells use B7‐H1 to promote local T cell tolerance.
Immune Response to HIV Infections
Immune Response to HIV Infections
HIV Infection
HIV Infection
dendritic cell (DC)
(DC)‐mediated di t d
HIV transmission CD4 and CD8 cell number during the course of HIV infection
Mechanisms of CD4+ T‐cell death in HIV infection
cDCs and pDCs during HIV infection.
viral load, and CD4 cell count will help your doctor determine the .
right time to start therapy
HIV medications or ARV therapy, including:
NNRTIs (or non‐Nucs): Non‐nucleoside reverse transcriptase inhibitors
NRTIs (or Nucs): Nucleoside reverse transcriptase inhibitors
PIs: Protease inhibitors
hb
Entry inhibitors
Integrase inhibitors
HIV Vaccine
Immune Response to Bacterial Infections
Extracellular vs intracellular bacteria Extracellular vs
intracellular bacteria
• Extracellular bacteria:
Phagocyte avoidance!!
Phagocyte avoidance!!
• Intracellular bacteria:
Cell‐mediated
Cell
mediated is the major immune response is the major immune response
against intracellular bacteria.
Immune Response to Bacterial Infections
Antibody‐mediated mechanisms
for combating
infection by
infection by extracellular bacteria.
Invade mechanisms by extracellular bacteria bacteria
Immunity against intracellular bacteria
Immunity against intracellular bacteria Tuberculosis Tuberculosis Phases of infection Mycobacterium tuberculosis.
tuberculosis
The natural history of Mycobacterium tuberculosis infection.
Immune Response to tuberculosis
Immune Response to tuberculosis
Macrophages are key effector cells in mycobacterial killing, but can also provide a niche for bacterial multiplication.
Events that might lead to failure of BCG in developing countries
Immune Response to Diseases Immune
Response to Diseases
Caused by Parasitic Worms y
Diseases Caused by Parasitic Worms
Diseases Caused by Parasitic Worms
Body covering
Sex
Example diseases in humans
Cestodes (tapeworms)
Trematodes (flukes)
Nematodes Nematodes
(roundworms)
Tegument
Tegument
Cuticle
Hermaphroditic
Hermaphroditic, except Hermaphroditic,
except
schistosomes which are Dioecious
dioecious
Tapeworm infection
p
Schistosomiasis, swimmer's itch
swimmer's itch
Ascariasis, ,
dracunculiasis, elephantiasis, enterobiasis (pinworm), filariasis hookworm
filariasis, hookworm, onchocerciasis, trichinosis, trichuriasis
( p
(whipworm)
)
Schistosomiasis
Schistosomiasis is caused by digenetic blood trematodes.
The three main species infecting humans are Schistosoma haematobium S japonicum and S mansoni
haematobium, S. japonicum, and S. mansoni.
Life Cycle
Life Cycle
After infection with Schistosoma mansoni, the initial immune response
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