HC12- Immune response cancer Flashcards
no immunogenicity of cancer (2)
- cancer = own cells
- immune system unable to prevent cancer
immunogenicity of cancer (3)
- immune suppression > higher chance of cancer
- immune therapy
- detected immune response against melanoma
immunogenicity factors of cancer (6)
- viral antigens > HPV
- expression oncogenes > BRAF, Nras, p53, Her-2/neu
- difference in glycosylation antigens > MUC-1
- expression of embryonal antigens > MAGE, BAGE
- cancer testis antigen > NY-ESO-1
- higher expression of self-antigens > MART-1, gp100, tyrosinase
Cancer immunity cycle (CIC)
1 release of cancer antigen
2 cancer antigen presentation
3 priming and activation
4 trafficking of T cells to tumors
5 infiltration of T cells into tumors
6 recognition of cancer by T cells
7 killing of cancer cells
release of cancer antigen
cancer cell death
cancer antigen presentation
DCs/APCs
priming and activation
APCs and T cells
trafficking of T cells to tumors
CTLs
infiltration of T cells into tumors
CTLs and endothelial cells
recognition of cancer by T cells
CTLs and cancer cells
killing of cancer cells
immune and cancer cells
activation of naive CD8 T cell
MHC-1/ T cell receptor + B7/CD28
step 3 CIC > naive T cells need costimulation
autocrine loop of IL-2 induces proliferation and differentiation
effector function CD8 T cells (3)
- recognition of HLA/antigen
- T cell activation
- killing target > granzyme B and perforin
step 7 CIC
required to induce immune response
Innate immune response (5)
- macrophages, granulocytes, dendritic cells
- NK cells
- fast response > hours
- constant
- limitied number of specificities > receptor recognizes pathogen group
cellular adaptive immune response (4)
- CD8+ cytotoxic T cells
- CD4+ helper T cells
- gamma/delta T cells
- regulatory T cells
humoral adaptive immune response (2)
- antibodies against cell surface antigens > antibody-dependent cellular cytotoxicity (ADCC)
- antibodies against intracellular antigens > increased uptake antigens by DCs and antigen presentation
properties adaptive immune response
- slow > days/weeks
- response gets better in time
- variable > VDJ recombination
- large number of specific responses
immune therapy for melanoma > passive (2)
- anti-tumor antibodies
- activated T cells > TIL and engineerd
immune therapy for melanoma > active (6)
- tumor vaccines of irradiated tumor cells
- peptide vaccination
- dendritic cells loaded with tumor antigens
- immune stimulating adjuvants (TLR ligands)
- cytokines
- blockage of T cell regulation
immune escape tumors (3)
- loss of HLA or tumor antigen expression
- resistance against apoptosis
- blocking of T cell functions
