Mucosal immunoglobulins protect the olfactory organ of teleost fish against parasitic infection

Abstract

26The olfactory organ of vertebrates receives chemical cues present in the air or water and, at the same 27 time, they are exposed to invading pathogens. Nasal-associated lymphoid tissue (NALT) (which was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.The copyright holder for this preprint . http://dx.doi.org/10.1101/380691 doi: bioRxiv preprint first posted online Jul. 30, 2018; 3 Author Summary 46The olfactory organ is a vitally important chemosensory organ in vertebrates but it is also 47 continuously stimulated by pathogenic microorganisms in the external environment. In mammals and 48 birds, nasopharynx-associated lymphoid tissue (NALT) is considered the first line of immune 49 defense against inhaled antigens and in bony fish, protecting against water-borne infections.

Comparative models for human nasal infections and immunity

“…Interestingly, these responses are recorded even in the absence of virus in CNS tissues (Larragoite et al, 2016;Sepahi et al, 2018). With regards to specific antibody responses, it appears that IgT is the main antibody isotype involved in specific immune responses against protozoan parasites causing chronic infections in trout NALT (Yu et al, 2018). These findings confirmed that IgT is the functional equivalent to mammalian IgA in nasal secretions and that nasal IgT responses are likely the goldstandard to evaluate specific immune responses, at least in chronic infection models.…”

“…Finally, abundant MHC-II + antigen presenting cells are found in both the sensory and mucosal epithelium in the trout olfactory organ, but those located in the mucosal tips are found more apically and therefore closer to luminal antigens (Sepahi et al, 2016). Nasal immune responses of rainbow trout against neurotropic viruses such as rhabdoviruses (Tacchi et al, 2014;Larragoite et al, 2016) and protozoan parasites such as Ichthyophthirius multifiliis (Yu et al, 2018) have been described. These studies indicate that NALT mounts strong innate and adaptive immune responses upon vaccination or infection in bony fish.…”

Differential immune responses of immunoglobulin Z subclass members in antibacterial immunity in a zebrafish model

“…15,16 Thereafter, IgT was also found to be broadly distributed in skin-, nasal-and gill-associated lymphoid tissues (SALT, NALT and GIALT), with functional activities in mucosal immunity against parasitic infection and bacterial invasion. [17][18][19][20] The performance of IgT is similar to that of IgA in mammals. 21,22 Thus, IgZ/IgT of teleost represents the most ancient mucosal Ig class found in vertebrate species.…”

Advances in Intestinal Mucosal Immunoglobulins of Teleost Fish (A Review)

“…Fish are the first vertebrates to develop immunoglobulins, and adaptive immunity plays an important role in defense against pathogen infection in fish. Meanwhile, due to their special aquatic living environment, there are abundant immunoglobulins in mucosa-associated lymphoid tissues (nose, skin, gill, and intestine) and mucus of fish (Yu et al, 2018;Xu et al, 2016;Xu et al, 2013;Zhang et al, 2010). These immunoglobulins play an important role in the adaptive immune stage of fish resistance to pathogen infection.…”

“…There are a large number of immune active substances and immune cells in the nasal cavity, body surface, gill, and intestinal mucosa of fish. According to the location, the mucosa tissues of fish can be divided into nasal-associated lymphoid tissue, gutassociated lymphoid tissue, skin-associated lymphoid tissue, and gill-associated lymphoid tissue (Yu et al, 2018;Xu et al, 2016;Xu et al, 2013;Zhang et al, 2010).…”