Lymphocyte Activation Flashcards

Flashcards on Lymphocyte Activation

T cell vs. B cell antigen recognition

T cells need antigens to be processed and presented by MHC molecules, while B cells can recognize antigens in their native form.

Cross Presentation

A type of antigen handling where the antigen is processed and presented on MHC class I molecules instead of class II.

Immunological Synapse

The close contact between an antigen-presenting cell and a T cell, where molecules anchor the cells together.

Adhesion Molecules

Molecules that attach cells to one another within the immunological synapse; a mutation can result in an incapacity to fight infection.

Signal number one

Engagement of antigen on MHC seen by the T cell receptor

Signal number two

Costimulatory molecules that give a second signal in T cell activation.

T-cell immunity

Cell-mediated immune response.

B-cell immunity

Antibody-mediated immunity.

APCs

Antigen presenting cells that link the adaptive and innate immune system.

Pattern Recognition Receptors

Receptors on dendritic cells that recognize patterns on molecules associated with pathogens.

Leukocyte Adhesion Deficiency or LAD

syndrome caused by a mutation in LFA1 integrins, results in deficient bacterial infection defenses

CTLA-4 and PD-1

Important inhibitory receptors that terminate T cell activation cascades and represent targets for therapy.