Immunology Flashcards
What are the 2 central lymphoid tissues?
Thymus gland and bone marrow
What are the 3 peripheral lymphoid tissues?
Lymphnodes, peyers patches (ileum), spleen
Where is the site of B-cell localization and proliferation in a LN?
follicle
Where are the T-cell in a LN?
paracortex
What is found in the medulla of the LN?
medullary cords (closely packed lymphocytes and plasma cells)
The role of B-lymphocytes is categorized as what kind of immunity?
humoral
What is produced with humoral immunity?
antibodies
The role of T-lymphocytes is categorized as what kind of immunity?
cell mediated
What kind of chemical activates components of immune system (i.e. activates macrophages, PMNs, etc)?
lymphokines (subset of cytokines produced by lymphocytes)
what is the function of basophils?
they function in the inflammation response by releasing histamine and other chemical that act on the blood vessels.
what is the function of eosinophils?
they destroy parasitic organisms
what is the function of neutrophils?
they recognize foreign antigens and destroy them through phagocytosis (often the first to respond)
what is the function of monocytes/macrophages?
they engulf foreign antigens and cell debris and process antigen and present it
what is the function of B-lymphocytes?
they are independently able to identify foreign antigens and differentiate into antibody producing plasma and memory cells.
Which LN drains the head and neck?
cervical LNs
Which LN drains the upper limb, breast, and skin above the umbilicus?
Axillary LNs
What drains (lymph) the right side of the body above the diaphragm?
Right lymphatic duct
What drains the rest of the lymph into the junction of the left subclavian and internal jugular veins?
thoracic duct
What is the function of the natural killer cells?
Use perforin and granzymes to induce apoptosis of virally infected cells and tumor cells. Induced by non-specific activation (MHC 1). Also only lymphocyte member of the innate immune system.
what is the role of macrophages in the spleen?
they remove encapsulated bacteria
What is the consequence of splenic dysfunction? (post-splenectomy or sickle cell disease)
dec IgM –> dec complement activation –> increased susceptibility to encapsulated organisms.
what do we see (histo) post splenectomy?
howell-jolly bodies, target cell, thrombocytosis
which encapsulated organisms are we worried about with a damaged spleen?
Strep pneumoniae, H. influenzae type B, Neisseria meningitis, E.coli, Salmonella, klebsiella, and group B strep
where are B and T cell made?
bone marrow
Where do T cell mature?
Thymus = site of T-cell differentiation and maturation.
what are the components of adaptive immunity?
T cell, B cell, and circulating antibodies
what are the components of innate immunity?
neutrophils, macrophages, monocytes, dendritic cells, NK cells (lymphoid origin), and complement
What type of response do we see in innate immunity?
non-specific
what type of response do we see in adaptive immunity
highly specific, refined overtime– memory response becomes faster and more robust.
What proteins are secreted in innate immunity?
lysozyme, complement, CRP, defensins, etc.
What proteins are secreted in adaptive immunity?
immunoglobulins
what is the key feature of pathogen recognition in innate immunity?
Toll-like receptors (TLRs): pattern recognition receptors that recognize pathogen associated molecular patterns.
what is the key feature of pathogen recognition in adaptive immunity?
memory cells: activated B and T cells
where is MHC class 1 expressed?
expressed on all nucleated cells (not on RBCs)
where is MHC class 2 expressed?
only on antigen presenting cell: dendritic cells, macrophages, and B-cells (plasma cells)
what is the function of MHC class 1?
to present endogenously synthesized antigens (e.g viral) to CD8+ cytotoxic T cells.
what is the function of MHC class 2?
to present exogenously synthesized proteins (e.g. bacterial proteins, viral capsid proteins) to T-Helper cells.
what diseases are associated with HLA B27?
PAIR: Psoriatic arthritis, Ankylosing spondylitis, arthritis of Inflammatory bowel disease, Reactive arthritis
what disease is associated with HLA DQ2/DQ8?
celiacs dz
what disease is associated with HLA DR4?
Rheumatoid arthritis, and type 1 diabetes