Cellular Mechanisms of Immune Response CLN 372 PDF

wee zus 1jan & In 23 listnes Cellular mechanisms of immune response Lecture 2 CLN 372 Nutritional Immunology Dr. May Alsayb  (Pa...

wee zus 1jan & In 23 listnes Cellular mechanisms of immune response Lecture 2 CLN 372 Nutritional Immunology Dr. May Alsayb  (Part 1) Learning outcome: Understand the two important biological events of immune system Differentiate between the types of immune response Differentiate between active and passive immunities  wate - work as massea bakiam are & ay Xo ma The two important biological events of the immune system start a to activate signal this signal thenation attachment , , joi Recognition of the target pathogen- > Tike Pathogen: Any organism with the potential to cause disease. locker & Key There are five broad categories of pathogens, namely, viruses, bacteria, fungi, parasites and prions, each with different mechanisms of transmission, infection and reproduction. respons after the first step Effective defense against it napput. & Wide variety of cellular and molecules are present in the immune system to provide effective recognition and defensive strategies against all pathogens.  out of the ↓ an tigen > - anything body Inon-micro Deterre.. non-self- microorgansim We Recognition of the target pathogen on now the offerent between the house self The recognition properties based on recognizing chemical structures that are characteristic of infectious pathogens (non-self) and differ from components of host structures (self). These include various microbial lipids, carbohydrates, proteins and even nucleic & receptor acids that are collectively termed Pathogen‐Associated Molecular Patterns indecele on 7 Crousel - >redbuy a (PAMPs).- Athe pathogen microcus the that the immune Immune cells have evolved mechanisms capable of recognizing these patterns and recognize are termed Pattern Recognition Receptors (PRR) pAMPS PRR a ↓ ↓ receptorGreat Pathoge immense or tem y ,  Recognition of the target pathogen i The immune system distinguishes cells and molecules that belong within the body (self) from those that do not (nonself) , using the innate and adaptive immune systems. cluttercepbe - Both the innate and adaptive immune systems use cell-surface and soluble receptors to sense potential threats. Cells and molecules of the innate immune system respond rapidly to a microbial invasion and are often sufficient for defense.  memories have without Types of immune response help woud first line Sufficient ↑ effect & Innate immune response: provides immediate protection against d microbial invasion Adaptive immune response: develops more slowly and provides Y more specialized defense against infections first time take time to umio , know how metus witimtak they already - know  Innate immune response (Natural Immunity) [ 3 Innate immune response provide early defense against infection, compromises of 4 types of defensive barriers: Anatomic or physical (skin, mucous membrane). win Physiological (temperature, pH, complement and some cytokines). Phagocytic (neutrophils, macrophages, monocytes). animate Inflammatory events.  Innate immune response (Natural Immunity) it give It depend on the auto Characteristics of innate immune response: identity Nonspecific: only recognize molecules shared by groups of related microbes L and molecules produced by damaged host cells No memory cell to recognize Limited diversity - don't give many  InterbeiAdaptive nce immune response (acquired immunity) easel The adaptive immune system main strategies to combat most microbes. Antibodies. Secreted antibodies bind to extracellular microbes, block their ability i celli to infect host cells, and promote their ingestion and subsequent destruction by phagocytes. pathogeness - & block to prevented - - G 19 = meet Phagocytosis. Phagocytes ingest microbes and kill them, and antibodies and - helper T cells enhance the microbicidal abilities of the phagocytes. Cell killing. Cytotoxic T lymphocytes (CTLs) destroy cells infected by microbes that are inaccessible to anti- bodies and phagocytic destruction - wil land LTsa if it crub no Adaptive immune response (acquired immunity) Adaptive immunity consists of : Humoral immunity, in which Antibodies neutralize and eradicate - extracellular microbes and toxins. Cell-mediated immunity, in which T lymphocytes eradicate - intracellular microbes. -  Adaptive immune response (acquired immunity) i n cre ase Characteristics of adaptive immunity: replication cell lime Clonal expansion: Increases the number of antigen-specific lymphocytes to combat microbes will will Specific: Ensures that the immune response to a microbe is targeted to that microbe. Vo Memory: Increases the ability to combat repeat infections by the same microbe Diversity: Enables the immune system to respond to a large variety of antigens Nonreactivity to self : Prevents injury to the host during responses to foreign antigens before go out of the bore marrow if get leadme w & p  Immunological defense strategies type of micro/where is it The defensive strategy that the immune system relies on the biological nature of I the microbe and the site of the infection wither its intracellular or extracellular. D Extracellular pathogens (e.g. bacteria and parasitic worms) are directly exposed to antibodies, complement, phagocytes (macrophages and neutrophils) and eosinophils. element Intracellular pathogens, like viruses that generate cytosolic antigens, are targeted by interferons that block their replication and killer cells (NK and T cells) that induce apoptosis of the infected cells. ·  the defensive made body the day the boyo laut Active and Passive immunities make varim > - memory coll Active immunity is conferred by a host response to a microbe or microbial antigen, passive immunity is conferred by adoptive transfer of antibodies or T lymphocytes > No memory cell of - specific for the microbe. Both forms of immunity provide resistance to infection and are specific for microbial antigens, but only [ active immune> responses - generate immunologic memory. Therapeutic passive transfer of antibodies, but not lymphocytes, is done routinely and also occurs during pregnancy (from mother to fetus). fetus like from mother to medication the body to not make it verby for example like (log) it come  Active and Passive immunities algebr  Active and Passive immunities Antibody produced Antibody obtained by own body from others By the end of part 1you should know the following Understand the types of immunity and how do they differ Differentiate between innate and adaptive immunity Differentiate between active and passive immunity  Part 2: Learning outcome: Understand how immune system is regulated Understand the factors that affect immune responses  Immune Regulation When functioning properly (physiological conditions), the innate and adaptive immune systems recognize and attack non-self proteins while leaving self protein relatively un-harmed. · regelker 22/01/2025 | 19  Immune Regulation cell 1 X & einalm Positive & Negative Selection mechanisms in the thymus and bone marrow proces eliminate overtly self-reactive T cells and B cells during development. These mechanisms, however, cannot eliminate all potentially self-reactive cells because the adaptive immune system often encounters self molecules that were not present during receptor selection within the thymus or did not appear until ! a later point of development. 22/01/2025 | 20  Immune Regulation Unregulated adaptive immune responses are harmful. Without immune regulation, the adaptive immune response would be in a constant state of immunologic outrage (Pro-inflammation) attacking all non-self epitopes to which we are constantly exposed (e.g., food, drink, cosmetics), many of which pose no threat, wantand at those vital epitopes to which we are infrequently exposed (e.g., maternal– element fetal interactions). 22/01/2025 | 21  Regulatory Cells Regulatory T cells inhibit the activity of autoreactive lymphocytes. 1. CD4+ Treg cells: estimated to constitute 5% to 10% of peripheral CD4+ T cells. They are present in the absence of intentional immunization and are therefore ve only sometimes called natural Treg cells. boy need it like after vaccination 2. CD8+ suppressor cells: These cells are an inhibitory subpopulation of CD8+ T cells. needed recancer 22/01/2025 | 22  Factors influencing immune response 1.Immunodeficiency 2.Age 3.Hormones 4.Nutrition  Immunodeficiency primary Disorders caused by defective immunity are called immunodeficiency diseases. D Some of these diseases may result from genetic abnormalities in one or more - components of the immune system; these are called congenital (or primary) - - immunodeficiency. -  Immunodeficiency secondly Other defects in the immune system may result from infections, nutritional abnormalities, or medical treatments that cause loss or inadequate function of various components of the immune system; these are called acquired (or secondary) immunodeficiency.  Factors influencing immune response Age Very old or very young more susceptible to infectious disease Some infections are more severe in adults than in young children due to hypersensitivity Old person are highly susceptible to infections due to declined immune responses  Factors influencing immune response Hormonal Endocrine disorders such as diabetes, hypothyroidism, and adrenal dysfunction are associated with enhanced sensitivity of infections During pregnancy high levels of steroid is associated to susceptibility to many infections Some of the corticosteroid hormones have an anti-inflammatory and anti-phagocytes depress host’s resistance  Factors influencing immune response Nutrition Malnutrition: reduced cell mediated and humoral immunity Cell mediated immune responses decreases in sever protein deficiency  Effect of undernutrition on immune responses Basically almost all types of immunity are affected by the severe nutritional problems but non-specific defense and - cell-mediated immunity are much more affected as compared with humoral responses (Saeed. F, 2015) The effect of undernutrition on immune responses is deteriorative and may cause atrophy of organs and dysfunction of specific tissues, change the number and ratio of different cells and ultimately cause degenerative losses resulting in - malfunction in the immune cells (Chaplin, 2010). bo the lymph note begawatt malnutrition causes Effect of undernutrition on immune responses (Saeed. F, 2015) =  By the end of Part 2 you should know the following: Describe the roles of immune molecules in innate immune response Understand how immune system is regulated Understand the outcome of unregulated immune system Understand the effect of undernutrition on immune responses Thank you