On human cells MHC molecules are used to identify cancerous cells.
On bacterial cells things like LPS and various surface proteins are identified as "foreign"
The problem with this is that not all molecules that are used to identify "friend or foe" are attached to the surface. Things like non-methylated CpG, LPS, peptidoglycan and dsRNA all activate PRRs in cells, leading to an immune response. If you want a more comprehensive answer please contact me.
Tc cells are cytotoxic cells that are "effetors" of cellular immunity that carry out the attack on a foreign cells in other words Tc cells kill cells that have been infected by a foreign substance
The immune system's ability to recognize and resist specific foreign substances is determined by the unique set of proteins on the surface of cells called major histocompatibility complex (MHC) molecules. MHC molecules present antigens to immune cells, which stimulate the immune response. The immune system can only respond to antigens that are recognized by MHC molecules.
This process is called cell-mediated immunity. T cells, specifically cytotoxic T cells, recognize and destroy cells that are infected with a pathogen or abnormal cells, such as cancer cells. This immune response is crucial for clearing infections and providing immunity against future exposures to the same antigen.
Mediators of humoral immunity include antibodies, which are produced by B cells and circulate in the bloodstream. These antibodies can recognize and bind to specific antigens, marking them for destruction by other immune cells. In addition, cytokines released by activated B cells and helper T cells help regulate the immune response and stimulate antibody production.
The major histocompatibility complex (MHC) molecules are marker molecules on cells that the immune system uses to recognize pathogens. MHC molecules present fragments of pathogens on the cell surface to alert immune cells to the presence of the pathogen. This helps the immune system to target and eliminate infected cells.
Cell-mediated immunity is provided by T cells, a subset of white blood cells that directly attack and destroy infected cells or foreign substances in the body. T cells are activated when they recognize specific antigens presented by antigen-presenting cells such as dendritic cells or macrophages. This type of immunity is crucial for fighting intracellular pathogens and cancer cells.
Lymphocytes are part of the human body's innate immune system. Natural killer cells seek out and destroy foreign cells by distinguishing surface molecules of major histocompatibility complex class.
Tc cells are cytotoxic cells that are "effetors" of cellular immunity that carry out the attack on a foreign cells in other words Tc cells kill cells that have been infected by a foreign substance
The immune system's ability to recognize and resist specific foreign substances is determined by the unique set of proteins on the surface of cells called major histocompatibility complex (MHC) molecules. MHC molecules present antigens to immune cells, which stimulate the immune response. The immune system can only respond to antigens that are recognized by MHC molecules.
The ability to gain( from another individual of the same species ) immunity from foreign cells.
White blood cells, more specifically B-lymphocytes.
This process is called cell-mediated immunity. T cells, specifically cytotoxic T cells, recognize and destroy cells that are infected with a pathogen or abnormal cells, such as cancer cells. This immune response is crucial for clearing infections and providing immunity against future exposures to the same antigen.
The cells of the innate system recognize and respond to the pathogens in a specific generic way.
Tonsils are the immune systems first-line of defense against inhaled pathogens. They produce T-cells, a type of white blood cell that aids in immunity. The spleen helps with immunity by purifying the blood and helps the immune system recognize and attack foreign antibodies.
Immunity is the body's defense mechanism against pathogens like bacteria, viruses, and other foreign substances. It involves two main types: innate immunity, which provides immediate but non-specific protection, and adaptive immunity, which develops over time and targets specific invaders. The immune system utilizes various cells, such as lymphocytes (B cells and T cells), to recognize and remember pathogens, enabling a quicker and more effective response upon subsequent exposures. Additionally, antibodies produced by B cells neutralize pathogens, while T cells help destroy infected cells or assist other immune cells.
MHC doesn't "recognize" bacteria or anything. It's job is simply take up the broken peptides. These peptides can be originally from a virus, bacteria, or from the cell itself (self). It will take these antigen that it can bind to and bring it to the cells surface. Your adaptive immunity cells (B and T cells) job is to "see" what the MHC has to offer and identify it as self (leave alone) or as foreign (need to destroy).
Humoral immunity