The piglet as a model for B cell and immune system development

Abstract

The ability to identify factors responsible for disease in all species depends on the ability to separate those factors which are environmental from those that are intrinsic. This is particularly important for studies on the development of the adaptive immune response of neonates. Studies on laboratory rodents or primates have been ambiguous because neither the effect of environmental nor maternal factors on the newborn can be controlled in mammals that: (i) transmit potential maternal immunoregulatory factors in utero and (ii) are altricial and cannot be reared after birth without their mothers. Employing the newborn piglet model can address each of these concerns. However, it comes at the price of having first to characterize the immune system of swine and its development. This review focuses on the porcine B cell system, especially on the methods used for its characterization in fetal studies and neonatal piglets. Understanding these procedures is important in the interpretation of the data obtained. Studies on neonatal piglets have (a) provided valuable information on the development of the adaptive immune system, (b) lead to important advances in evolutionary biology, (c) aided our understanding of passive immunity and (d) provided opportunities to use swine to address specific issues in veterinary and biomedical research and immunotherapy. This review summarizes the history of the development of the piglet as a model for antibody repertoire development, thus providing a framework to guide future investigators.

Antibody Repertoire Development in Fetal and Neonatal Piglets. XX. B Cell Lymphogenesis Is Absent in the Ileal Peyer’s Patches, Their Repertoire Development Is Antigen Dependent, and They Are Not Required for B Cell Maintenance

“…The IPP appears to be a specialized secondary lymphoid tissue that appears during late fetal life in the absence of environment influences in contrast to the JPP or conventional PP. Certain features of the IPP in fetal and newborn piglets distinguish it from secondary lymphoid tissues like spleen, such as the dominant expression of IgG3, the most primordial IgG for swine and most 59 in the locus (42,46,82). In mice, IgG3 (also the most 39 Cg gene) is important in marginal zone B cells and seems targeted to bacterial polysaccharides in a T-independent fashion (83,84).…”

“…The fetal B and T cell repertoires of both species develop without maternal influence and regulatory factors such as maternal IgG that are known to influence fetal immunological development in mice and rabbits (37)(38)(39)(40)(41). However, swine have multiple offspring (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20), weigh ,2 kg at birth, and can be conveniently reared in GF isolators after their recovery by cesarean surgery where all environmental and maternal factors are thereafter controlled by the experimenter (41,42). Furthermore, the V H repertoire of swine is well characterized, partially mapped, and has been followed during development using methods that quantify repertoire development and frequency of SHM (43)(44)(45)(46)(47).…”

Regulation of immunity and disease resistance by commensal microbes and chromatin modifications during zebrafish development

“…Using a similar model, Hrncir et al (27) found that bacterial LPS, which is present as a contaminant in mouse food, is needed to develop a healthy phenotype. Unfortunately, available model species are scarce, and most findings under GF conditions are derived largely from a few mammalian species, mainly rodents (28) and swine (29). Only recently, another species, the zebrafish, has emerged as a key and powerful model organism to widen basic and biomedical animal research (30)(31)(32)(33)(34)(35).…”

Timing of HAART defines the integrity of memory B cells and the longevity of humoral responses in HIV-1 vertically-infected children

“…However, no significantly different immunization schedules have been provided for these patients so far (11,12). Responses to immunizations are complex, requiring the integration of several components of the immune system, including B-and T-lymphocytes, which are under development during the 1st year of life (13)(14)(15). HIV-1 may quantitatively and qualitatively affect these cells in a time-dependent manner.…”