Review: Cells of the Immune System

From Larsson and Karlsson (2005)

Review: Cells of the Immune System

Larsson and Karlsson (2005)

Review: Myeloid cells

Dendritic cell

Review: Myeloid cells•Macrophages – phagocytes, antigen presenting cells (APCs), specialized cells different organs, secrete cytokines, produce complement proteins, can produce ROS/RNS.

•Neutrophils – phagoctyes, can produce ROS/RNS, secrete antimicrobial peptides, 1st cell type to migrate from blood to infections, main targets are bacteria and fungi

•Basophils – secrete cytokines, involved in allergic response

•Eosinophils – phagocyte, targets parasites

Lymphocytes:

T cellsB cells Natural killer cells

Review: Lymphocytes

• B cells – naïve B cells: contain antigen binding receptor (or membrane bound antibody), once activated –

memory cells: provides memory of antigen/antibody interaction; plasma cells: secrete soluble antibody

• T cells - contain antigen binding receptor (TCR)T H cells: secretes cytokines that activate B cells, T C cells,

macrophages and others.T C cells: eliminates altered/damaged self cells (particularly those infected by viruses), fights tumors cells, secrete

cytotoxins.T reg cells: helps suppress immune response, plays a role in

tolerance .

Review: Lymphocytes

Lymphoid cells

•Natural killer cells – distinct from T and B cells due to lack of an antigen binding receptor, similar in function to T C cells, macrophage activation, defense against viruses, fight tumor formation, secrete cytotoxins.

Derived from both lymphoid and myeloid precursors

•Dendritic cells – phagoctyes, antigen presenting cells (APCs), can produce ROS, secrete proinflammatory cytokines, secrete antimicrobial peptides.

Review: Cells of the Immune System

Review: Organs of the Immune SystemPrimary and secondary lymphoid organs:

Review: Innate and adaptive immunity

Review: Innate Immune Response

Review: Adaptive Immune ResponseAntigen/Antibody interactions:

Antigen – any substance that binds specifically to an antibody or a T cell receptor (TCR).

Antibody- a protein (immunoglobulin) that recognizes a specific region (component) of an antigen.

Properties of immunogenicity:ForeignnessMolecular sizeChemical composition/complexityProcessing/presentationHost factorsDosageRoute of entry

Antibody-Mediated Effector Functions

OpsonizationAssist and activate complement systemADCC