- T cell Receptor
Needs antigen + MHC complex
- B cell Receptor
Binds Antigen, leads to MHCII presentation and activation by T-Helpers
- MHC class I molecule
On all nucleated cell, presents foreign information of viral info (CD8)
- MHC class II molecule
DC cells, Macrophages, and B Cells, present engulfed foreign particle
- CD1
Related to MHC I activation on all cells
- Primary response for antibody production
Lag period in response because antigen is educating secondary immune cell. IgM first produced (weak affinity), then IgG response (IgG levels remain for a long time)
- Secondary response for antibody production
Faster response due to the remaining IgG and memory
- Memory
Adaptive Immune retaining response in B Cells
Myelocytes
Stem Cells in Bone Marrow
- Dendritic cells
Identifies PAMP’s and presents to and activates T Cells (only one that can)
- Macrophage
Phagocytosis/bactericidal mechanisms in tissue, less round shape o Kupfer Cell in Liver o Osteoclast in Bone o Histiocyte in Soft Tissue o Foam Cell in Plaque o Microglia in CNS o Multinucleated in Granuloma antigen presenting, unlike neutrophils
- Monocyte
= Found in blood, spherical
- Mast cell
Vesicles with triggered, discriminant release of histamine, heparin, TNFa. Starts Inflammation response due to TLR’s can be activated by complement
- Basophils
Reside in draining lymph nodes near parasites and allergies activated by complement
- Eosinophil
Allergies and large parasite. Fc Receptor for IgE, degranulate
- Neutrophil
Most abundant cell in circulation (stuck to lining), diapedesis due to stress. Fc receptors for IgG’s and complement. Can phagocytose and secrete lysozymes. Reaction can also harm the body.
- CD4+ Helper T cell
Recognize MHC II activate B Cells
- CD8+ Cytotoxic T cell
Recognizes MHC I Induce Apoptosis
- Natural killer Cell
Kill cells that do not have MHC1 and induce apoptosis
- Natural killer T cell
Found in Gut/antibacterial
- γδ T cell
Antibacterial, mucosal associated
- B-1 cell
High levels of IgM (Not Adaptive)
- B-2 cell
Resting Mature B Cell (Memory Cell)
Centrocyte
Not Replicating Activated B-Cell (negatively selected)
- Plasma cell
Antibody secreting B Cell, Express (ILR7)
- Follicular Dendritic cell
Found in secondary lymph organs, help with B-Cell Differentiation, expresses receptor that binds complement bound to antigen
- Th0
Activated Helper T Cell (IL2, Not IL12)
- Th1
Activates Memory T Cells, Secretes IFNgamma to induce Macrophage phagocytosis
- Th2
Help with B-Cell Differentiation, parasites
- Th17
= inflammatory Response cytokines, Fungi
- T-reg cells
= Produces IL10, shutting down other T Cells
- Role of IFNγ
Secreted by TH1, activates Macrophage Phagocytosis
- TGFβ
Treg inhibition of lymphocytes and macrophages
- IL4
Signal for Naïve T Cell to TH-2, Signals for B-Cell Class switch (IgE)
- IL-2
Autocrine signal released from Naïve T cell due to DC MHCII bound to Naïve T-Cell. Signals for development into mature T-cell in all T Cells
- Antigen presenting cells (Professional)
Dendritic Cell, Macrophage, Plasma Cell
Innate Immunity
Genetically hardwired, rapid, limited
- Complement
Limited innate immune protein cascade response produced by liver, drives phagocytosis, increases inflammatory response
- Sentinel cells
Cells responsible for discovering infection (Macrophages, DCs, Specialized TCells)
- Extravasation
Neutrophil passing through endothelium to enter tissue. Initiated by CXCL8
- Integrin
Expressed by sites of inflammation to facilitate Extravasation
Selectin
Binding protein on endothelium that Neutrophils bind for extravasation
- Role of Macrophage in inflammation
Control Protein levels in blood
- Role of Pro-Inflammatory cytokines
IL1 IL6 TNFa
o Activate Complement
o Mobilization of Neutrophils
o Increased body temperature, protein and energy mobilization
o Dendritic Cell recruitment for Adaptive Immune Initiation
- Acute Phase Response
o IL6 from macrophages signals for synthesis of Acute phase response proteins
o Mannose-Binding lectin = binds Mannose
o C-reactive Protein = opsoninization of bacteria
- Primary lymphoid organs
Bone Marrow (B Cell Mature), Thymus (Mature B Cells, Activated T Cells), Fetal Liver (Mast Cells)
- Secondary lymphoid organs
Site of lymphocyte education matching T and B cells to antigen. Lymph nodes, Peyers patch, spleen, appendix, tonsils
- Role of the Dendritic cell
Phagocytosis of non-self, via TLRs.
- Lymphocyte activation
Mature DC activate naïve T Cell development via MHC ClassII
- High endothelial venule
Primary lymphocytes express (CD62L), which allows entrance into lymph node via High Endothelial Lymph Node. Follicular Dendric Cells in HEV attract B-Cells for differentiation
- Humoral response, when is IgD present
IgD expression = cell has never been exposed to antigen on Follicular Dendritic Cell
- Resting mature B cells (B2)
Not yet specific, secrete IgM and IgD antibodies
Centrocyte
Not Replicating Activated B-Cell (negatively selected)
- Memory B-cell
Long Lasting, specific antibody secreting B-Cell (reason for secondary response)
- Plasma cell
Differentiated B-Cell (any type of antibody secreted)
- Clonal expansion
Replication of Specific B Cell after TH2 activation (positive selection)
- Somatic hypermutation
Making a very refined antibody via effective binding
- Class switching
TH2 mediated switch of Plasma Cell Produced Antibody isotype (IgG, IgM, IgD)
- Role of Th1
(IFNγ, Promotes macrophage activity, promotes macrophage mediated inflammation
o Activated through TLR2 pathways
o Increases Macrophage Activity
o Promotes more TH1 production
- Role of Th2
(IL-4, Humoral activity, allergy)
o Promotes more TH2 production
- Role of Th17
(IL-17, Inflammation and Neutrophil actions)
o Inflammatory response and neutrophil recruitment
- Role of Treg
(TGF-β/IL-12, Down regulates antigen specific T cell activity)
o Activated via TLR4, decreasing macrophage activity (Allows for fungal infection)
- Mantoux test and delayed type hypersensitivity
o Induce TH1 reaction via local macrophages expressing MHCII-TB antigen
- Measles
drives a Th2 response that allows for secondary infections
o Measles infects nodes and kills T-Cells
o DC shift the TH2 response, allows for continued infection
o Immune system very compromised
Skin
- Parasites, Protozoa, Fungal, Viral
- Langerhans
- Neutrophils
- Macrophages
- Eosinophils
Interstitial
- Virus and Bacteria
- Macrophage
- CD4+ Helper T Cell
- Cytotoxic T Cell
- NK Cells
Mucosal
- Bacterial and Viruses
- Macrophage
- Dendritic Cell
- Gamma-delta T Cell
- B1 Cells