Question

EXPLAIN the immune system response in the following scenario with the given components:

1. E. coli found inside a poorly cooked hamburger patty. Remember, E. coli has the capability to produce toxins and is Gram-negative therefore has endotoxin present as well.

Components: Mucous, mucous membranes, gastric juices, T helper cells, cytotoxic T cells, B cells, antibodies, cytokines, interferons, macrophages and dendritic cells, neutrophils, complement

Answer 1

E. coli secrete lipopolysaccharide (LPS), which is present in the wall of this gram negative bacteria and act as very dangerous endotoxin to the system. In uncooked food, they have fair chance to infect an individual through mucous secretion, they may cause destruction of mucous cell and in extreme condition endotoxin causes sepsis also. Further, they can reach to gastric region where have to face adverse pH (extremely low) and this is also one of the reason for low pH in stomach. Once E. coli reach the small intestine, which is best part for microbial and other pathogens. A number of immune cells also come in to the picture once the recognize the xenobiotic in the system. T helper lymphocytes, B or T cells along with cytotoxic cells (all variant of lymphocytes or WBCs), immune system recognize invasion of pathogenic E. coli and induce production of antibodies to cope of with bacteria through attachment on active domain and some leukocytes eat the E. coli through phagocytosis as a result of immune response. Several interleukins and other cytokines, chemokines also express against E.coli and similarly other leukocytes also help in the execution of E. coli like neutrophils and dendritic cells (accessary cell for antigen recognition and binding). Please note that interferon express in case of viral infection not bacterial infection.