Download BY44 Microbiology Chapter 19

Chapter 19
DISORDERS
ASSOCIATED
with the
IMMUNE SYSTEM
Dr. Reitano
DISORDERS ASSOCIATED with the
IMMUNE SYSTEM
FAILURES of the IMMUNE SYSTEM:
– _____________
– _____IMMUNITY – ex. lupus, multiple sclerosis
– _______________________
HARMFUL IMMUNE REACTIONS
–
-HYPERSENSITIVITY//ALLERGIC REACTIONS
Response to antigens (allergens) to an
extreme degree leading to damage
Requires ___________ dose(s)
-_____________________
HYPERSENSITIVITY
REACTIONS
• Type I - Anaphylactic Reactions
– Involves _____ antibodies
• Type II – _________ Reactions
– Involves IgG or IgM Abs and complement
• Type III – ____________ Reactions
– Involves IgG Abs and antigen complexes that
lodge in basement membranes of blood vessels
• Type IV – Cell-Mediated Reactions
– Involves delayed _________________
TYPE I - ______________ REACTIONS
Involve IgE antibodies
binding to mast cells or
basophils with release of
reactive substances (histamines)
• Localized: ________(food) or inhaled(pollen)
antigens-common allergic reactions such as
hay fever, asthma
• Systemic: Shock, breathing difficulties from
injected antigens (______________)
Figure 19.1a
TYPE II - CYTOTOXIC REACTIONS
• Involve IgG or IgM antibodies and
complement
• Complement activation causes ________ or
damage by macrophages
– Ex. BLOOD TRANSFUSIONS
___________ DISEASE of NEWBORN
TYPE III - IMMUNE COMPLEX REACTIONS
• __________ and antigens form complexes
that lodge in basement membranes of
blood vessels.
Figure 19.6
TYPE IV – CELL MEDIATED or DELAYED
TYPE HYPERSENSITIVITY REACTIONS
• Ags attract Tc cells which
destroy target cells
• ____________ attract
macrophages and initiate
tissue damage
• Ex. __________ rejection
_________________
Figure 19.8
REACTIONS to
TRANSPLANTATION
• Transplants may be attacked by T cells,
macrophages, and complement-fixing
antibodies.
• Transplants to ____________ sites do not
cause an immune response.
• Stem cells may allow therapeutic cloning
to avoid rejection.
TYPES of GRAFTS
• ______GRAFT: Use of one's own tissue
• ____GRAFT: Use of ____________ tissue
• ALLOGRAFT: Use of tissue from another
person
• XENOTRANSPLANTATION: Use of
____________ tissue
• GRAFT-VERSUS-HOST DISEASE: Can
result from transplanted ___________
that contains immunocompetent cells
IMMUNOSUPPRESSIONprevents immune response to transplanted tissues
1. CYCLOSPORINE
– suppresses IL-2
2. MYCOPHENOLATE MOFETIL
– inhibits T cell and B cell reproduction
3. SIROLIMUS
– blocks IL-2
IMMUNE DEFICIENCIES
CONGENITAL:
Due to defective or missing __________
_____________:
Develop during an individual's life, due to
drugs, cancers, infections
Artificial: Immunosuppressive drugs
_______: ____ infections
THE IMMUNE SYSTEM and CANCER
• Cancer cells possess tumor-specific ___________
• TC cells recognize and lyse cancer cells
• Cancer cells may lack tumor antigens or kill TC
cells
Figure 19.11
ACQUIRED IMMUNODEFICIENCY
SYNDROME (_________)
Figure 19.12a
_____ INFECTION
Capsid
Reverse
transcriptase
RNA
Virus
Two identical + stands of RNA
1 Retrovirus penetrates
host cell.
Host
cell
DNA of one of the host
cell’s chromosomes
5 Mature
retrovirus
leaves host
cell, acquiring
an envelope as
it buds out.
Reverse
transcriptase
Viral RNA
Identical
strands of
RNA
2 Virion penetrates
cell and its DNA is
uncoated
4 Transcription of the
Viral proteins
RNA
provirus may also occur,
producing RNA for new
retrovirus genomes and
RNA that codes for the
retrovirus capsid and
envelope proteins.
Provirus
3 The new viral DNA is
tranported into the host cell’s
nucleus and integrated as a
provirus. The provirus may
divide indefinitely with the
host cell DNA.
Figure 13.19
____ INFECTION
Figure 19.13
STAGES of HIV INFECTION
• Category A Asymptomatic or persistent
lymphadenopathy
• Category B Persistent ________________
infections
• Category C Clinical AIDS. CMV, Herpes sp,
tuberculosis, Pneumocystis sp.
cryptosporidiosis, Kaposi's
sarcoma
COMMON DISEASES ASSOCIATED with AIDS
Table 19.5
DIAGNOSTIC METHODS for HIV
• Seroconversion - takes up to 3
months
• _____ – for HIV antibody detection
• _______ blotting – for detection of
HIV antigens
• PCR or nucleic acid hybridizationto determine viral load in plasma
GLOBAL TRANSMISSION of HIV
•
•
•
•
Male to male homosexual conduct
___________sexual transmission
________ use
Infected body fluids transmit HIV via:
– Sexual contact
– Breast milk
– Transplacental infection of fetus
– Blood-contaminated needle
– Organ transplant
– Artificial insemination
– Blood transfusion
Worldwide Distribution of AIDS
and HIV
Figure 19.17
TREATMENT of HIV
• Vaccines
• Chemotherapy
• Highly Active Anti-Retroviral
Therapy (___________)
– Ex.:Combinations of reverse
___________ inhibitors + ________
__________ of AIDS
• Homosexual conduct*
• Use of _______ and sterile needles
• Health-case workers use universal
precautions
– Wear gloves, gowns, masks, goggles
– Do not recap needles
– Risk of infection from infected
needlestick injury is 0.3%