Evidence for a common mucosal immune system in the pig

Abstract

The majority of lymphocytes activated at mucosal sites receive instructions to home back to the local mucosa, but a portion also seed distal mucosa sites. By seeding distal sites with antigen-specific effector or memory lymphocytes, the foundation is laid for the animal's mucosal immune system to respond with a secondary response should to this antigen be encountered at this site in the future. The common mucosal immune system has been studied quite extensively in rodent models but less so in large animal models such as the pig. Reasons for this paucity of reported induction of the common mucosal immune system in this species may be that distal mucosal sites were examined but no induction was observed and therefore it was not reported. However, we suspect that the majority of investigators simply did not sample distal mucosal sites and therefore there is little evidence of immune response induction in the literature. It is our hope that more pig immunologists and infectious disease experts who perform mucosal immunizations or inoculations on pigs will sample distal mucosal sites and report their findings, whether results are positive or negative. In this review, we highlight papers that show that immunization/inoculation using one route triggers mucosal immune system induction locally, systemically, and within at least one distal mucosal site. Only by understanding whether immunizations at one site triggers immunity throughout the common mucosal immune system can we rationally develop vaccines for the pig, and through these works we can gather evidence about the mucosal immune system that may be extrapolated to other livestock species or humans.

Chitosan Derivatives and Their Application in Biomedicine

“…Mucosal vaccines have some advantages compared with traditionally vaccines, and most infections occur at a mucosal surface or spread from mucosal surfaces [201]. Studies have shown that mucosal administration could provide an early defense against invading pathogens, as the local antibodies of the mucosa work faster than serum antibodies, are higher in level, and have a greater maintenance time [202,203]. The process of immunity is shown in Figure 6 [204].…”

Microbiome and Anticancer Immunosurveillance

“…Moreover, the concept of a ''common mucosal immune system'' supports the idea that B and T cells primed locally in an initial mucosal site can seed distantly to other mucosal or lymphoid tissues. By seeding distal sites with antigen-specific effector or memory phenotypes, this mucosa-derived immunity would protect the host against any pathogen encountered in the future, irrespective of the portal of entry (Wilson and Obradovic, 2015), thus establishing ''functional connectiveness'' within the immune system (Kiyono and Fukuyama, 2004;Kunisawa et al, 2008;McGhee et al, 1992). This notion could explain the potential efficacy of immune checkpoint blockers such as anti-PD1/PD-L1 Ab against lung cancers in the context of intestinal Bifidobacteriumdependent T cell function resetting (Sivan et al, 2015).…”

Development of immune organs and functioning in humans and test animals: Implications for immune intervention studies

“…No data was found on immune function in minipig (information on immune function development in the pig is given by [79][80][81]). The data in rat and mouse could not be compared with the human data, because the immune parameters were very different.…”