Podcast
Questions and Answers
What type of disorder is Crohn's disease?
What type of disorder is Crohn's disease?
Which of the following is a form of hypersensitivity reaction?
Which of the following is a form of hypersensitivity reaction?
What characterizes ulcerative colitis?
What characterizes ulcerative colitis?
Which of these is not a factor contributing to IBD?
Which of these is not a factor contributing to IBD?
Signup and view all the answers
What is the largest independent risk factor for IBD?
What is the largest independent risk factor for IBD?
Signup and view all the answers
Which condition leads to a lack of new T cells and affects antibody production?
Which condition leads to a lack of new T cells and affects antibody production?
Signup and view all the answers
Up to what fraction of patients with CD have a first-degree relative with the disease?
Up to what fraction of patients with CD have a first-degree relative with the disease?
Signup and view all the answers
What type of infections does HIV infection predispose individuals to?
What type of infections does HIV infection predispose individuals to?
Signup and view all the answers
Which therapy is used to inhibit the entry of HIV into the host cell?
Which therapy is used to inhibit the entry of HIV into the host cell?
Signup and view all the answers
What kind of inflammatory response can superantigens cause?
What kind of inflammatory response can superantigens cause?
Signup and view all the answers
Which chromosomes have been identified with susceptibility loci for UC and CD?
Which chromosomes have been identified with susceptibility loci for UC and CD?
Signup and view all the answers
HAART combined with IL-2 mainly aims to:
HAART combined with IL-2 mainly aims to:
Signup and view all the answers
What is a significant immunological consequence of HIV infection?
What is a significant immunological consequence of HIV infection?
Signup and view all the answers
Which problem is associated with HIV vaccines?
Which problem is associated with HIV vaccines?
Signup and view all the answers
Which of the following is not a factor leading to acquired immunodeficiency?
Which of the following is not a factor leading to acquired immunodeficiency?
Signup and view all the answers
What is a common result of protein-calorie malnutrition related to the immune system?
What is a common result of protein-calorie malnutrition related to the immune system?
Signup and view all the answers
Which gene is associated with Crohn's disease in white populations?
Which gene is associated with Crohn's disease in white populations?
Signup and view all the answers
What role does the NOD2 protein play in the immune system?
What role does the NOD2 protein play in the immune system?
Signup and view all the answers
Where is the NOD2 protein primarily expressed?
Where is the NOD2 protein primarily expressed?
Signup and view all the answers
Which type of cells infiltrate the bowel wall in Crohn's disease?
Which type of cells infiltrate the bowel wall in Crohn's disease?
Signup and view all the answers
What does the immune theory of IBD assume?
What does the immune theory of IBD assume?
Signup and view all the answers
What mechanism is excessive with Crohn's disease (CD)?
What mechanism is excessive with Crohn's disease (CD)?
Signup and view all the answers
Which cytokine's expression is increased in the intestinal mucosa of IBD patients?
Which cytokine's expression is increased in the intestinal mucosa of IBD patients?
Signup and view all the answers
How is inflammation in IBD maintained?
How is inflammation in IBD maintained?
Signup and view all the answers
Study Notes
Acquired Immunodeficiency
- Caused by other diseases or conditions, including aging, protein-calorie malnutrition, cancer treatment, immunosuppressive therapies, and HIV infection.
- HIV infection leads to severe secondary immunodeficiency, causing dysfunction and deficiency of B cells, T cells, and phagocytic cells, and decreased cell-mediated cytotoxicity by natural killer cells.
Immunomodulation
- HAART (Highly Active Antiretroviral Therapy) and IL-2 can reconstitute the immune system and slow apoptosis of HIV-infected cells.
- Chemokine receptor inhibitors can prevent HIV entry into host cells.
- Vaccines, including proteins, DNA, subunit, and recombinant virus (SIV-HIV chimeric virus), can stimulate immune response.
Problems with Immunomodulation
- HIV-1 infection allows the virus to shield itself from recognition by antibodies.
- Low immunogenicity and delayed response due to low CD4+ T cell counts.
- Destruction of CD4+ T cells by vaccine.
- Integration of virus in host genome.
- High rate of virus replication.
- Challenges with vaccine development, including route of exposure and lack of animal models.
Disorders of the Immune System
- Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease.
- Reactions of hypersensitivity, including allergic rhinitis and anaphylaxis.
- Autoimmune diseases, including rheumatoid arthritis and multiple sclerosis.
- Immunodeficiency syndromes, including primary and acquired immunodeficiency.
Inflammatory Bowel Disease (IBD)
- Caused by a dysregulated immune response.
- Two forms: ulcerative colitis (mucosal inflammation confined to the rectum and colon) and Crohn's disease (transmural inflammation of the GI tract).
- Etiologies include dysregulated immune response, host genetics, and environmental factors.
Etiologies of IBD
- Dysregulated immune response.
- Host genetics.
- Environmental factors, including commensals, pathogens, antibiotics, diet, stress, and barrier function.
Infectious Factors
- Certain bacterial strains produce toxins that cause mucosal damage.
- Bacteria produce peptides that cause an influx of inflammatory cells.
- Microbes may elaborate superantigens that stimulate global T lymphocyte stimulation.
Genetic Factors
- Positive family history is a significant risk factor.
- Increased concordance for the disease in monozygotic twins.
- Polygenic disease, with susceptibility loci on multiple chromosomes.
- Linkage mutations have been found on CARD15/NOD2, IBD5, and IBD3 loci.
The Role of NOD2 in the Immune System
- NOD2 recognizes bacterial molecules and stimulates an immune reaction.
- Encodes a protein with two caspase recruitment domains and eleven leucine-rich repeats.
- Expressed in peripheral blood leukocytes.
- Plays a critical role in immune response by recognizing bacterial molecules and activating NF-κB.
Immunological Mechanism of IBD
- The immune system plays a critical role in the pathogenesis of IBD.
- Infiltration of lymphocytes, plasma cells, mast cells, macrophages, and neutrophils in the bowel wall and mucosal layer.
- Inflammation is maintained by an influx of leukocytes from the vascular system into sites of active disease.
- The influx is promoted by expression of adhesion molecules on endothelial cells.
The Immune Theory of IBD
- IBD is caused by an inappropriate reaction of the immune system.
- Potential immunologic mechanisms include both autoimmune and non-autoimmune phenomena.
- Dysregulation of cytokines is a component of IBD.
- Th1 cytokine activity is excessive in CD, while Th2 cytokine activity is excessive in UC.
- Patients have an inappropriate T cell response to antigens from their own intestinal microflora.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
This quiz covers the various causes of acquired immunodeficiency syndrome, including aging, malnutrition, cancer treatment, and HIV infection.
