Introduction to Immunology. 1&2 Flashcards
The body’s defense system can be divided into
- Natural/Innate/Non-specific
E.g unbroken skin, Any body’s secretion, Basic proteins like: lysosome, lysozyme, lysoferrin e.t.c, cells: PMNs, macrophages, NK cells - Adaptive/Acuired/specific:
Cellular immunity- T-cells
Humoral- B-cells
Which immunity is capable of recognizing antigens
Adaptive
Acute inflammation is a component of
Innate
Defense against Intracellular microbes by adaptive immunity is specifically by
Cell mediated(T lymphocytes)
Defense against extracellular microbes by adaptive immunity is specifically by
Humoral(B lymphocytes)
Antibodies are secreted by
B cells
The three ways in which antibodies work
Neutralization
Opsonization- interaction with phagocytes
Complement activation-direct lysis
What are antibodies
Cell surface Receptors(immunoglobulin molecules) of B cells(Derived and matured in Bone marrow )
Developement of T lymphocyte
Arise in bone marrow but mature’s in Thymus
Organs of immune system
Bone marrow
Thymus
Spleen
MALT
Primary lymphoid organs
Bone marrow
Thymus
Secondary lymphoid organ
Spleen
Peyer’s patches
Tonsils and adenoids
Collections in lungs,git,liver
Percentage of T-lymphocytes making up blood lymphocytes
60-70%
Percentages of CD4+ and CD8+ respectively.
60%
30%
Master regulators
CD4+
What areas in the LN and spleen is T lymphocytes found
Paracortical
Periarterial
2 signals for activation of Tcells
- MHC-bound antigen with TCR
2. CD28 molecules on T cells with BT-1, BT-2 expressed on APC
Division of CD4
TH1- IL2, interferon gamma-yIFN(for delayed hypersensitivity), macrophage activation, synthesis of igG2B
TH2- secretes IL4,IL5 which aids type 1 hypersensitivity rxn
CD4 binds to what MHC on antigens
MHCII
CD8 binds to what MHC on APC
MHC I
B-lymphocytes constitute how many percentage of lymphocytes
10-20%
Macrophages plays both -&- function of immune response
Induction and effector
What presents antigen to immunocompetent T-cells
Macrophages
What plays the effector role in delayed hypersensitivity rxn
Macrophages