Peroral Immunization of Germfree Piglets: Appearance of Antibody‐forming Cells and Antibodies of Different Isotypes

Abstract

Precolostral germfree piglets were perorally immunized with sheep erythrocytes daily, beginning on the 5th day of life. At different intervals the numbers of IgM, IgG and IgA antibody-forming cells were estimated in the spleens, lymph nodes and intestinal mucosa by the haemolytic plaque method. In the beginning of the response IgM antibody-forming cells were detected in intestinal mucosa and mesenteric lymph nodes. IgA plaque-forming cells appeared later and were predominant during the whole period in all organs tested. In all lymphatic organs tested the appearance of IgG antibody-producing cells followed that of IgA plaque-forming cells. The development of immunoglobulins and antibody of different isotypes in intestinal contents and sera was compared with the cellular kinetics found in these young animals after local stimulation.

IgA Isotype Restriction in the Mucosal but Not in the Extramucosal Immune Response after Oral Immunizations with Cholera Toxin or Cholera B Subunit

“…Paradoxically, the increased plasma titers were associated with a decreased number of antibody forming cells in mesenteric lymph nodes and spleen. The cause of the decreased number of antibody-form ing cells after repeated immunizations with CT re mains unexplained, but similar observations using other antigens have recently been reported [23,29], The transfer experiments described in the present communication do not support the notion that sup pression by cells or serum factors is responsible for the observed reduction. However, another possible explanation would be that the localization of antibody-forming cells changes with increasing numbers of immunizations.…”

The role of gut microbiota (commensal bacteria) and the mucosal barrier in the pathogenesis of inflammatory and autoimmune diseases and cancer: contribution of germ-free and gnotobiotic animal models of human diseases

“…During the early postnatal period, the intestinal microbiota stimulates the development of both local and systemic immunity, while later on these components evoke inhibitory regulatory mechanisms intended to keep both mucosal and systemic immunity in check. [35][36][37] The importance of the microbiota in the structural and functional features of the developing immune system was predicted by Professor Jaroslav Šterzl, who established the Laboratory of Gnotobiology at the Institute of Microbiology more than 50 years ago. This crucial development provided tools to study basic questions about the host-microbiota interaction using various animal models.…”

“…[38][39][40][41][42][43][44] We have shown that microbial colonization of animals living in germ-free conditions results in an increase in immunoglobulin levels, the production of specific antibodies, substantial changes in mucosal-associated lymphocyte tissues and cell populations, changes in migration patterns and increases in the systemic immunological capacity. 35,40,42,43 In the early postnatal period, components of the normal microbiota induce a transient physiological inflammatory response in the gut associated with enlargement of the mucosal-associated lymphatic tissue and increases in its cellularity. 39,45 The effect of microbial colonization on innate immune cells has been documented in our studies on the development of phagocytes, dendritic cells and intestinal epithelial cells.…”

Mucosal Immunity: Its Role in Defense and Allergy

“…expression of surface costimulatory molecules and production of IL-12 necessary for activation of Th1 cells. We have shown that before induction of oral tolerance a period of increased immune reactivity and creation of memory cells is detectable [29, 45]. …”

“…The normal flora strongly influences the development of both the gut lymphatic tissue and the whole immune system, as demonstrated by comparing animals reared in germfree conditions (gnotobiotic models) and reared conventionally or under specific-pathogen-free (SPF) conditions [26, 27, 28]. Our gnotobiological studies aided in distinguishing spontaneously occurring immune mechanisms from those developing under the influence of microorganisms and shed light on the development of innate immunity, resistance to infections, mucosal immunity, B cell repertoire, cellular immunity, tolerance induction, effect of cytokines [29, 30, 31, 32, 33]. Gnotobiotic models, in combination with functional genomics and proteomics, will soon bring more light into the molecular mechanisms regulating the host-commensal microflora interaction [28].…”