Immune responses

Immune responses to foreign and self-antigens require specific and balanced responses to clear pathogens and tumors and yet maintain tolerance.
Keir et al. 2008

The selectivity of the immune response is dictated by sensors that recognize the stimulus, by the downstream signaling pathways, and by the transcriptional and chromatin regulators activated by these pathways.
Heinz et al. 2015 Nat. Rev. Mol. Cell Biol. 16: 144-154
Glass & Natoli 2016 Nat. Immunol. 17: 26-33
Monticelli & Natoli 2017 Nat. Rev. Immunol. 17: 595-607
Natoli & Ostuni 2019 Nat. Immunol. 20: 783-792
Sheu & Hoffmann 2022 Annu. Rev. Immunol. 40: 295-321

A well-balanced immune response is crucial for the health and survival of an organism. When the immune system becomes overly active and pro-inflammatory, it can lead to immune dysregulation. This dysregulation is associated with a variety of autoimmune and inflammatory diseases. Serum amyloid A proteins cause the formation of pathogenic CD4+ Th17 cells, which in turn contribute to the development of inflammatory diseases.
Medzhitov 2008 Nature 454: 428-435
Lee et al. 2020 Cell 183: 2036-2039

Different types of immune responses are specialized based on the type of pathogen:

• Type 1 immune response targets phagocyte-resistant intracellular pathogens.


• Type 2 immune response targets extracellular Parasites / Parasitism and helminths.


• Type 3 immune response targets extracellular bacteria.
  Type 3 immunity involves immune cells that produce specific cytokines, like Interleukin-17 Family / Interleukin-17 (IL-17) and IL-10 family cytokines, which help strengthen the body's defenses by acting on non-immune cells, such as barrier epithelial cells.

Mangan et al. 2006 Nature 441: 231-234
Zheng et al. 2008 Nat Med 14: 282-289
Sonnenberg et al. 2011 Immunity 34:122–134.
Mangan et al. 2006 Nature 441: 231-234

see also:
Biological effects / Functions & Interleukin-22 (IL-22)
Lymphoid Tissue Inducer Cells (LTi cells)