10 Step in the Antibody-Mediated Immune Response

Engulfment of Bacterium: A __________ cell in the infected tissue recognizes a bacterium as foreign and engulfs it by __________.

dendritic, phagocytosis

Degradation of Bacterium and Release of Antigens: Engulfment activates the dendritic cell, which migrates to a nearby __________. The bacterium is degraded into short peptides that serve as __________.

lymph node, antigens

Presentation of Antigens on Dendritic Cell Surface: Antigens bind to unique class II __________ proteins and are displayed on the cell surface, converting the dendritic cell into an __________.

MHC (Major Histocompatibility Complex), antigen-present cell (APC)

Interaction of Antigen-Presenting Cell with Lymphocyte: The antigen-presenting cell interacts with a specific __________ T cell, linking the two cells together.

CD4+

Activation of T Cell: The antigen-presenting cell secretes __________ (a cytokine), which activates the associated T cell.

interleukin

Production of Helper T Cells: Activated T cells undergo clonal __________ and differentiate into __________ T cells, which assist in activating B cells.

expansion, helper

Presentation of Antigens on B Cell Surface: B cells present antigens on their surface in complex with class II __________ proteins after binding to bacterial antigens.

MHC

Interaction of B Cell with Helper T Cell: B cells encountering helper T cells with the same antigen become __________ linked.

tightly

Activation of B Cell: Helper T cells secrete __________, which activate the B cell and stimulate clonal __________.

interleukins, proliferation

Production of Plasma Cells and Memory B Cells: Cloned B cells differentiate into __________ cells, which secrete antibodies, and __________ B cells for long-term immunity.

plasma, memory