In vivo lnterleukin-4 Regulation of Antibody Responses in Euthymic and Athymic Mice to a T-lndependent Antigen (Hydroxyethyl Starch)

Abstract

The aim of this work was to analyze the implication of IL-4 in the antibody response induced in vivo after immunization with a class II T-cell-independent (TI) antigen. IL-4 suppression, through administration of a rat monoclonal antibody antimurine IL-4 (11B11), in euthymic BALB/c mice during the course of immunization with the DNP-coupled hydroxyethyl starch (TI antigen), inhibited the production of anti-DNP IgG1 antibodies, potentiated the synthesis of IgG2a and had no effect on other isotypes (IgM, IgG2b and IgG3). After IL-4 treatment of athymic BALB/c mice in the same conditions, although the IgG2a production was not increased, the IgGl synthesis was significantly decreased, as was observed in euthymic mice. These results demonstrate that cytokine IL-4 plays an active role in vivo in the regulation of antibody response after immunization by a T-cell-independent antigen, in normal as well as in nude mice. The origin of IL-4 in these animals and especially in those athymic mice remains to be determined.

Up-Regulation of CD40 Ligand and Induction of a Th2 Response in Children Immunized with Pneumococcal Polysaccharide Vaccines

“…Our results are in agreement with the observation of an IL-4 regulation of in vivo antibody production in response to TI-2 antigens in experimental animals (11). Th1 cells do not appear to be involved in the response to pneumococcal polysaccharides, since neither IL-12 nor IFN-␥ mRNA increased in our experiments.…”

“…TI antigens have been subdivided into type 1 (TI-1) antigens, which have no T-cell interaction, and type 2 (TI-2) antigens, which have some interaction with T cells. Recent studies have shown that pneumococcal polysaccharides are TI-2 antigens, which stimulate T-cell help in regulating antibody production (11,14,20,21,31). However, neither the way in which such stimulation occurs nor the regulatory mechanism of antibody production is well understood.…”

PAS‐1, a protein affinity purified from Ascaris suum worms, maintains the ability to modulate the immune response to a bystander antigen

“…Ovalbumin (OVA) five times crystallized and keyhole limpet hemocyanin (KLH) were obtained from Calbiochem (La Jolla, CA, USA). DNP‐OVA and DNP‐hydroxyethylstarch (DNP‐HES), thymus‐dependent and thymus‐independent antigens, respectively, were prepared, as previously described 22 23 .…”

“…DNP-OVA and DNP-hydroxyethylstarch (DNP-HES), thymusdependent and thymus-independent antigens, respectively, were prepared, as previously described. 22 A. suum worm extract (ASC) was prepared as described by Strejan and Campbell. 23 The protein component from A. suum adult worm extract, PAS-1, was purified by affinity chromatography using the mAb MAIP-1 coupled to Sepharose 4B, as previously described.…”