Phagocytes present antigens to T cells, and by which pathways do they achieve this

1. Exogenous antigen presentation process: Exogenous antigens are ingested into the cell by APC to form phagosomes through phagocytosis or phagocytosis, and the latter fuses with lysosomes to form phagolysosomes. The antigen is degraded into small molecule polypeptides by proteolytic enzymes in the acidic environment of the phagolysosome, among which the immunogenic ones are called antigenic peptides.

After the MHC-like molecules synthesized in the endoplasmic reticulum enter the Golgi apparatus, they are carried by secretory vesicles, and by fusing with phagolysosomes, the antigenic peptides combine with the MHC-like molecules in the vesicles to form antigenic peptide-MHC-like molecular complexes. This complex is expressed on the surface of APCs and can be recognized and bound by the corresponding CD4+ T cells.

2. Endogenous antigen presentation process: Endogenous antigen refers to the antigen synthesized by the cell itself, such as tumor antigen and viral protein antigen. After endogenous antigens are generated in cells, they can be degraded into small molecule polypeptides by the proteasomes present in the cytosol, that is, small polymeric polypeptide bodies (LMPs). After the small molecule polypeptide binds to heat shock protein 70 90 in the cytoplasm, it is transported to the endoplasmic reticulum by the antigenic peptide transporter (TAP), and becomes an antigenic peptide with immunogenicity through processing and modification. Antigenic peptides bind to MHC molecules synthesized in the endoplasmic reticulum to form antigenic peptides-MHC molecules to form antigenic peptide-MHC molecular complexes. The latter is transferred to the Golgi apparatus and transported to the surface of the APC by secretory vesicles for recognition and binding by the corresponding CD8+ T cells.

Answer]: Mu Ling absolutely a

Antigen-presenting cells (APCs) are a class of immune cells that can ingest, process, and process antigens, and present the processed antigens to T and B lymphocytes. APC mainly includes monocytic phagocytes, dendritic cells, B cells, endothelial cells, and target cells of viral infection of tumor cells.

The surface of each antigen will have some special protein structures that are specific and are called epitopes. After the macrophage engulfs the antigen, the antigen determinant of the antigen is exposed and released after digestion and presented to the T cells. Thus, what macrophages present to T cells is the antigen's epitope, a protein that is unique to the antigen's surface.

It is not the antigen itself or something else that is presented to the T cells.

See T cells. Thought to be talking about the T virus in Resident Evil...

The answer is: b.

A false, phagocytic cells phagocytosis bacterial antigens are not specific;

C false, the processed antigen can be presented directly to T lymphocytes instead of B lymphocytes;

D, antigen processing and presentation processes exist in both humoral and cellular immunity.

Pick BA: False. Phagocytic phagocytic pathogens do not have specificity B: Correct. The globules above the phagocytic cell are lysosomal C: wrong. Phagocytes present antigens to T cells.

The cells that have the effects of engulfing jujube phagocytosis, antigen presentation and secretion are () cells.

Cell. c.Talking about nucleation - macrophages.

d.Mesophils.

Correct answer: c

The roles of phagocytic cells and T cells in humoral immunity are:

The role of phagocytes: the antigen is processed so that the epitope is exposed for recognition.

The role of T cells: to present antigens, to present antigens to B cells.