Transcript 10_12_immuno~2

201 Immunology: goals
• Goal - to provide you with an overview of key
concepts in immunology:
– innate and adaptive immune responses
– cells and molecules involved in immune responses
– interactions that result in the recognition of microbes by the
immune system
– immune effector responses
– regulation of immune responses
– specific mechanisms involved in immune responses to
viruses, bacteria, and cancer cells
• Organizer: Otoniel (Otto) Martínez
([email protected])
201 Immunology: faculty
• Instructors:
– Otto Martínez, PhD
– Larry Feldman, PhD
– David Blanco, PhD (laboratory)
• Clinical Conference Speakers:
– Gary Schiller, MD
– Michael Cecka, PhD
– Ardis Moe, MD
– Adrian Casillas, MD
201 Immunology: overall structure
• Introduction to immunology concepts
– 3 lectures (Martínez)
• Molecules and cells that interact with antigens
– 3 lectures (Feldman)
• Development and regulation of the immune system
– 3 lectures (Martínez)
• Immune responses to cancer, viruses, bacteria
– 3 lectures (Martínez and Feldman)
• Clinical conferences and immunology laboratory
201 Immunology: clinical conferences
• Bone marrow transplantation (BMT)
– August 16, Friday (Schiller)
• Allergy
– August 19, Monday (Casillas)
• AIDS
– August 26, Monday (Moe)
• Immunology laboratory
– September 9, Monday (Blanco)
• Major histocompatibility complex (MHC)
– September 23, Monday (Cecka)
201 Immunology: reference books
• The Immune System
(Peter Parham)
• Immunobiology
(Janeway, Travers, Walport, Shlomchik)
• Other textbooks:
– Abbas, Roitt
• www sources: PubMed
– http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=Books
– Immunobiology, 5th edition in searchable format
Introduction: role of the immune system in
host defense
• The immune system has evolved to protect us from
pathogens that are present in our environment (viruses,
bacteria, fungi, protozoa and multicellular parasites).
Introduction: role of the immune system in
host defense
• Immunity has evolved to protect us from pathogens that
are present in our environment (viruses, bacteria, fungi,
protozoa and multicellular parasites).
• Therefore, the immune system is of interest because it plays
a key role in protection from infection.
• Immune responses that result in the control or elimination of
infection are termed protective immunity.
While immunology is a relatively new science, an intuitive
understanding if immunity has been around for some time:
– immunity evolves from the latin word inmunis, which was derived
from in (free or exempt from, without) and munus (civil services
or taxation)
– first recorded mention of the phenomenon of immunity (in
European history) is by Thucydides (460-404 BC, Athens), who
described the great pestilence of 430-429 BC in Athens, during
the second year of the Peloponnesian War, an outbreak that
killed more than 30,000 people (out of a population of 172,000)
– Thucydides noted that those who had recovered would not
contract the disease a second time: “the sick and the dying were
tended by the pitying care of those who had recovered, because
they knew the course of the disease and were themselves free
from apprehensions ... for no one was ever attacked a second
time, or not with a fatal result”
Deliberate attempts to induce immunity (15th century) to smallpox:
variolation
Understanding that prior exposure to an infectious agent can
result in protection on subsequent exposure to that same agent
led to the development of vaccination.
– Edward Jenner - developed an effective
vaccine to smallpox, using a similar virus,
cowpox virus (vaccine is derived from the
latin word vaca)
Many effective vaccines have been developed based on an
empirical understanding of immune responses.
However, a thorough, mechanistic understanding of immune
responses has been developed only in recent years.
SSPE = subacute
sclerosing
panencephalitis
(brain disease that is a
late consequence of
measles in a small
fraction of patients)
The cells that
make up the
immune system
interact to
recognize, then
respond to,
pathogens.
cytokines
Monocyte
*
*
*
* *
*
*
*
cytokines
ACTIVATION
cytokines
*
Therefore,
immune
responses can be
divided into two
related activities:
recognition and
response.
TH
TH
*
*
TH
*
*
*
*
* *
*
*
CTL-P
TH
* *
B
*
*
cytokines
PROLIFERATION
*
*
B
B
*
*
*
*
CTL
CTL
*
*
DIFFERENTIATION =
CELL KILLING
*
*
*
Plasma
cell
Plasma
cell
*
*
*
*
*
*
*
*
DIFFERENTIATION = Ig PRODUCTION
• In addition to this, several features of immune responses,
such as memory and specificity, have captivated the
interest of biologists for many years.
• In the last half of this century, significant insights on how the
immune system can recognize and respond to infectious
agents vigorously and with such great specificity.
• It is clear that the immune system can act as an integrative
system, analogous to the endocrine or nervous systems, in
that it can receive information from the local and systemic
environment, assess and integrate this information in some
way, and respond appropriately with a series of effector
functions, which result in significant biological changes.
Physical Barriers to Pathogens
• Before considering innate and adaptive immune
mechanisms, it is worth noting that there are various nonimmune, natural physical barriers prevent entry and/or the
establishment of pathogens:
– skin
– mucus
– tears (lysozyme)
– ciliated epithelial cells
– low pH in the GI tract
Physical Barriers to Pathogens
• Before considering innate and adaptive immune
mechanisms, it is worth noting that there are various nonimmune, natural physical barriers prevent entry and/or the
establishment of pathogens:
– skin
– mucus
– tears (lysozyme)
– ciliated epithelial cells
– low pH in the GI tract
• These physical barriers are of great importance in protecting
the host from infection, providing effective barriers that can
be penetrated by few infectious agents.