Immunology Colloquium 1 Past Paper - 2022-2023 - PDF

# Evaluation "X" in the "yes" column indicates the correct answer. The answers that are not marked, i.e. those considered incorrect, are also counted. In case of a mistake, please clearly state "yes" or "no". The shaded circles indicate also the correct answer. ## 1. The following cells are the...

# Evaluation "X" in the "yes" column indicates the correct answer. The answers that are not marked, i.e. those considered incorrect, are also counted. In case of a mistake, please clearly state "yes" or "no". The shaded circles indicate also the correct answer. ## 1. The following cells are the main players in the innate defence system: - dendritic cells - natural killer cells (NK) - neutrophils - phagocytes - lymphocytes (BT) → adaptive ## 2. Physiological role of the immune system is: - Control of tissue regeneration and scarring - Defence against transplantation - Defence against infections - Defence against tumours - Inducing of allergy ## 3. Immunity: - active immunity is induced in humans by infections - passive immunity is induced in humans by vaccination - active immunity is induced if antibodies from another already immune individuals are intravenously administrated to patients with agammaglobulinemia - passive immunity is induced if lymphocytes from another already immune individuals are intravenously administrated to humans with immunodeficiency - passive immunity protect neonatal ## 4. Functions of adaptive immunity are: - blocking of infections by secretion of antibodies - elimination of extracellular microbes by cytokines - killing of infected cells and elimination of infection reservoirs by cytotoxic lymphocyte T - elimination of phagocytosed microbes by secreted antibodies - elimination of phagocytosed microbes by activation of macrophages, which are activated by cytokines secreted by helper T lymphocytes ## 5. Immune response: - the clonal expansion rapidly increases the number of neutrophils after infection - after infection of new microbes innate response is faster than adaptive - the unresponsiveness to self is called immunological tolerance - Antigen-presenting Cells (APCs) dendritic cells capture of antigen for initiation of lymphocytes T response - Effector B lymphocytes-plasma cells - develop in response to antigenic stimulation in peripheral lymphoid organs for antibody production ## 6. Cytokines produced by T helpers by recognition of the microbial antigen presented by APCs: - activate macrophages - kill the infected cells - activate inflammation - activate C1 of complement by classical pathway - activate B lymphocytes ## 7. Immunological memory - memory cells can survive for long periods in the absence of antigen - frequency of memory cells decrease with age - memory cells are functionally active in absence of antigens - when memory cells encounter the same antigen that induced their development, the cells rapidly respond to initiate secondary immune response - cytokine are involve to generate memory cells ## 8. Peripheral lymphoid organs and tissues: - the highest number of lymphocytes is present in bone marrow - blood-borne antigens are captured and concentrated by dendritic cells and macrophages in spleen - the macrophages in spleen ingest and destroy old red blood cells - the major components of the cutaneous immune system present in dermis are: plasma cells, mast cells, macrophages, T lymphocyte CD4+ and dermal dendritic cells; in epidermis: keranocytes, epidermal Langerhans cells and intraepithelial lymphocyte CD8+ - M cells in cutaneous immune system are organised in specialised Peyer's patch structures ## Department of Human Physiology and Pathophysiology Version B ## 9. Complement system: - can be initiated by antibodies binding to microbes in alternative pathway - is activated when mannose binding lectin MBL, binds to its carbohydrate ligands on microbes in absence of antibodies and is a typical innate pathway of complement system activation - plays 3 main functions in defence: C3b by opsonisation and phagocytosis; C5a and C3a promote movement of leucocytes into tissue by inflammation; MAC formation disturb permeability of microbial cell membrane and leads to cell lysis - can be activated by SARS-Cov2 and activated coagulation cascade - SARS-Cov2 inhibits C1-Inhibitor and by the way blocks activation of complement system ## 10. Specificities of Toll-like receptors (TLR) - TLR-4 is specific for lipopolysaccharide (LPS ) of Gram-negative bacteria - TLR-1 is specific for bacterial lipopeptides of Gram-negative bacteria - TLR-2 is specific for bacterial lipopeptides of Gram-positive bacteria - TLR-5 is specific for bacterial flagellin of Gram-positive bacteria - TLR-2 is specific for bacterial peptidoglycan of Gram-positive bacteria but also gram neg. idk ## 11. Inflammation - TLR engagement by bacterial molecules increase expression of proinflammatory cytokines - TLR engagement by bacterial molecules increase expression of adhesion molecules for extracellular traps - COX1 and COX2 are activated in arachidonic cycle for prostaglandin expression - arachidonic acid is a product of cellular membrane injury and activation of phospholipase A2 - IL-1beta and IL-18 inhibits inflammation in apoptosis ## 12. Antiviral defence - the RIG-like receptors (RLRs) are cytosolic proteins that sense viral RNA and induce production of antiviral type I interferon - RLRs recognise features of typical mammalian double stranded dsRNA - activated RLRs interact with mitochondrial antiviral-signalling (MAVS) - cytosolic DNA sensors (CDSs) recognize double stranded dsDNA in the cytosol and initiate type I interferon production and autophagy - type I interferon production is stimulate by activation of the stimulator of INF genes (STING pathway) by binding of GAMP to endoplasmatico reticulum membrane adaptor protein STING after activation of CDSS ## Department of Human Physiology and Pathophysiology Version B ## 13. Cytokine: - Macrophages produce Tumour Necrosis Factor (TNF), IL-1 and IL-6 for synthesis of acute phase proteins in liver - TNF can started apoptosis of many cell types - the principal cell sources of IL-12 are: endothelial cells, some epithelial cells and mast cells - IFN-alpha is produced by fibroblasts - IFN-gamma activates macrophages ## 14. Precipitation is used: - in radial immunodiffusion to measure of the antigen titter - in determining agammaglobulinemia in immunoelectrophoresis - in immunohistochemistry for visualisation of proteins in the tissue - in electrophoresis of the serum proteins in agammaglobulinemia - in determination of increased CRP in latex test ## 15. Cases: - in Quincke's hereditary angioedema-HAE, C1-INH is strong increased - in systemic lupus erythematosus SLE complement system damages vascular endothelial cells and leads to nephropathy - mutations in a single Bruton tyrosine kinase (Btk) gene, located on the X chromosome cause agammaglobulinemia ICD10 D800 - detection of antibacterial IgG without IgM in cassette tests pointed of acute bacterial infection - non-productive cough, fever, increased lymphocytes in blood make it possible to suspect interstitial viral pneumonia