Download Immunological disorders

Immunological disorders -szöveg
SLIDE 1 in the final part of the lecture I’ll talk about 4 disease, here you can check the topics.
these have a common feature, they are all based on the immune system disorders. And they
are polygenic diseases.
SLIDE 2 Immune system is the body's defense against infectious organisms. It’s role is to
distinguish between the self and non-self molecules, and to identify and kill
the pathogens and tumor cells.
SLIDE 3 the immune system composed of Primary and Secondary lymphoid organs. The
adaptive immune system is antigen specific and reacts only with the organism that induced
the response. In contrast, the innate system is not antigen specific and reacts equally well to a
variety of organisms. Finally, the adaptive immune system demonstrates immunological
memory.
SLIDE 4 Immune disorders are very diverse; they can affect the whole body or can be more
localized. The symptoms of each disease depend on which part or parts of the body are
attacked by the immune system. In some cases, the immune system overreacts to the foreign
allergens (pollen, etc), but in many cases it attacks the own body cells (autoimmunity).
SLIDE 5 Hypersensitivity refers to excessive, undesirable reactions produced by the normal
immune system. Hypersensitivity reactions can be divided into four types: type I, type II, type
III and type IV, based on the mechanisms involved and time taken for the reaction.
SLIDE 6 Type I hypersensitivity is also known as immediate hypersensitivity, it is mediated by IgE.
SLIDE 7-8 Asthma is characterized by inflammation of the airways that results in a
narrowing of the air passages in the lungs. Asthma runs strongly in families and genetic
variants have been identified that play a significant role in the development of Asthma.
Symptoms of Asthma include difficulty in breathing, wheezing, coughing, and a feeling of
tightness in the chest. Asthma can be mild, or it can be severe and require frequent
hospitalizations. In rare asthma can be deadly. Asthma is a common chronic disease, affecting
over 300 million people around the world. Approximately 1 in every 10 people will develop
asthma during their lifetime. In the United States, 20 million people have been diagnosed with
asthma. Genetic factors are known to play a significant role in the development of asthma.
Three common genetic variants, on chromosomes 2, 9 and 17 have been associated with an increased
risk of developing asthma. Here you can see the top 100 genes: associated with asthma.
SLIDE 9 Allergic rhinitis, pollenosis or hay fever is an allergic inflammation it is also an IgEmediated reaction, following exposure to an allergen. AR is a global health problem. Many genes,
chromosomal region, polymorphisms are associated with hay fever.
SLIDE 10 Type II hypersensitivity is also known as cytotoxic hypersensitivity and may affect a
variety of organs and tissues.
SLIDE 11 Type III hypersensitivity is also known as immune complex hypersensitivity. The reaction
may be general or may involve individual organs including skin.
SLIDE 12 Rheumatoid arthritis is a chronic inflammatory autoimmune disease of the joints. It is a
progressive disease that can lead to long-term joint damage, resulting in chronic pain, loss of function,
and disability. Female gender and genetic factors are the most common known risk factors for
Rheumatoid arthritis. There are certain environmental factors that increase the risk of developing this
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Immunological disorders -szöveg
disease. For example: cigarette smoking, high body mass index (BMI). RA is also a systemic disease,
which means it can affect other organs in the body including the skin, heart, lungs, eyes, and muscles.
RA can affect anyone, including children, but 70% of people with RA are women. Onset usually
occurs between 30 and 50 years of age. Genetic variants are known to increase the risk of developing
Rheumatoid arthritis.
SLIDE 13 Type IV hypersensitivity is also known as cell mediated or delayed type hypersensitivity.
SLIDE 14 One sample of Type IV Hs is Type 1 Diabetes. It can occur at any age, but usually
first develops in childhood or adolescence. Type 1 Diabetes is less common that Type 2
Diabetes. Although this type of diabetes can occur at any age, it usually first develops in
childhood or adolescence. In fact, Type 1 Diabetes is one of the most common chronic
diseases in childhood and adolescence. About 1 in every 400 to 600 children and adolescents
develops Type 1 Diabetes, and currently it is estimated that more than 700,000 Americans
have the disease, or 0.4% of the population. The incidence of Type 1 Diabetes is increasing in
many parts of the world. Over the past 40 years, a major increase has been reported in
theincidence of T1D in many European countries as well as in the US. The number of new
cases of T1D in the US has in recent years been increasing by approximately 3% per year.
The reason for this is unclear, but some research suggests that viral infections may trigger the
disease in genetically susceptible individuals. Type 1 Diabetes is defined as an autoimmune
disease. In this type of diabetes, the immune system attacks and destroys the islet cells of the
pancreas. These cells normally produce insulin, the hormone that moves sugar from the
bloodstream into the body’s cells and tissues, where it can be used for energy. It is unknown
what first starts this autoimmune reaction, but evidence suggests that both a genetic
predisposition and environmental factors are involved. When the islet cells are destroyed,
little or no insulin is produced, which means that sugar cannot be moved out of the blood and
blood sugar levels rise. Because the body can´t make use of the sugar, it spills over into the
urine and is lost. Weakness, weight loss, frequent urination, and excessive thirst are among
the early symptoms. Genetic factors play a significant role in T1D. Although the cause of Type 1
Diabetes is largely unknown, it has been shown that genetic factors are important risk factors. Twentyeight genetic variants have been identified that increase the risk of developing Type 1 Diabetes.
SLIDE 15 The HLA (human leukocyte antigen, is the name of the major histocompatibility
complex (MHC) in humans. ) One gene in the HLA region that plays an important role in
diabetes is called DR. People can inherit one form of DR from their mother and one form of
DR from their father. Two forms of DR, designated DR3 and DR4, are present in 95 % of Type
1 diabetics, and 30 % have inherited both DR3 and DR4. This is in contrast with the general
population, where only 50 % of people have DR3 or DR4 and 1 to 3 percent have both.
Diabetics who have inherited DR3 (but not DR4) develop diabetes at an older age.
Diabetics who have inherited DR4 (but not DR3) tend to develop diabetes earlier in life.
Diabetics who inherit both DR3 and DR4 develop diabetes at the youngest. Another gene
in the HLA region, called DQ, Like DR, certain versions of the DQ gene put a person at
higher risk for developing the disease, while other forms seem to be protective. To make
matters worse, people who inherit DR3 or DR4 also inherit a form of DQ that adds to
their risk of developing diabetes. Conversely, the protective forms of DQ and DR inherited
together. The insulin gene is the region of DNA that codes for the protein insulin. This
region determines how much insulin the gene makes. It is composed of a repeated section of
DNA called the VNTR. Smaller VNTR regions contain only 26 to 63 DNA repeats, while long
regions contain 140 to 200 repeats. If a person inherits two short VNTR regions, they are two
to five times more likely to develop T1D than a person with at least one long VNTR.
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