Effects of the adjuvants SGP and Quil A on the induction of experimental autoimmune thyroiditis in mice

Evaluation of antithyroglobulin antibodies after routine vaccination in pet and research dogs

OBJECTIVE

To determine whether routine vaccination induces antibodies against bovine thyroglobulin and autoantibodies against canine thyroglobulin in dogs.

DESIGN

Prospective study.

ANIMALS

20 healthy research Beagles and 16 healthy pet dogs.

PROCEDURE

For the research Beagles, 5 dogs were vaccinated with a multivalent vaccine and a rabies vaccine, 5 dogs received only the multivalent vaccine, 5 dogs received only the rabies vaccine, and 5 dogs were unvaccinated controls. The multivalent vaccine was administered at 8, 10, 12, 16, 20, 26, and 52 weeks of age and every 6 months thereafter. The rabies vaccine was administered at 16 and 52 weeks of age and then once per year. Blood was collected from all dogs at 8, 16, and 26 weeks of age and then 4 times yearly. Assays for antibodies directed against bovine and canine thyroglobulin were performed prior to and 2 weeks after each yearly vaccination. For the pet dogs, blood was collected prior to and 2 weeks after 1 vaccination.

RESULTS

In the research Beagles, there was a significant increase in anti-bovine thyroglobulin antibodies in all vaccinated dogs, compared with control dogs. There was a significant increase in anti-canine thyroglobulin antibodies in the 2 groups of dogs that received the rabies vaccine but not in the group that received the multivalent vaccine alone. In the pet dogs, there was a significant increase in anti-canine thyroglobulin antibodies after vaccination but no significant change in anti-bovine thyroglobulin antibodies.

CONCLUSIONS AND CLINICAL RELEVANCE

Recent vaccination may result in increased anti-canine thyroglobulin antibodies. Whether these antibodies have a deleterious effect on canine thyroid function is unknown.

Molecular structure and granulocyte/macrophage colony-stimulating factor activity

Granulocyte/macrophage colony-stimulating factor (GM-CSF) plays a critical role in myeloid differentiation and in several immune and inflammatory processes. GM-CSF binds to specific cellular receptors (GM-CSFR) which belong to a recently described supergene family. These receptors are potential targets for pharmacologic design and such design depends on a molecular understanding of ligand-receptor interactions. We present our initial studies evaluating the potential active sites of the molecule. The sites on the GM-CSF molecule that were studied represent two alpha-helices predicted to be critical for GM-CSF activity, as implicated by human-murine chimeric molecule studies. These helices are predicted to be adjacent in native GM-CSF. Peptides corresponding to amino acids 17-31 and 78-99 of GM-CSF were synthesized and cross-linked to one another in two different orientations. The ability of anti-GM-CSF to bind the individual and complexed peptides was evaluated by both ELISA and radioimmunoassay. Significant binding to all peptides was demonstrated. A preferred orientation of the two peptides was apparent, and this agreed with the predicted model structures. Antibodies were developed against the coupled peptides, and these demonstrated significant cross-reactivity with recombinant human GM-CSF. Additionally, analyses of anti-peptide antisera binding studies predict these two amino acid sequences to lie in parallel planes to one another in the native human GM-CSF molecule.

Effects of anti-I-A and anti-I-E monoclonal antibodies on the induction and expression of experimental autoimmune thyroiditis in mice

Susceptibility to experimental autoimmune thyroiditis (EAT) in mice is linked to the I-A subregion of the major histocompatibility complex (MHC). The present study was undertaken to assess the effectiveness of anti-I-Ak monoclonal antibody (MAb) 10-2.16 in preventing or arresting the development of EAT. Spleen cells from CBA/J or (CBA/J x Balb/c) F1 mice given 10-2.16 prior to sensitization with mouse thyroglobulin (MTg) and adjuvant could not transfer EAT to normal recipients, and cells from these mice did not proliferate in vitro to MTg. Donor CBA/J mice given 10-2.16 before immunization and recipients of cells from such mice produced little MTg-specific IgG1 or IgG2b antibody but did produce nearly as much IgG2a as controls. The effects of in vivo treatment with 10-2.16 appear to be due to elimination of Ia + cells rather than to modulation of Ia or induction of suppressor T cells. When 10-2.16 was added to in vitro cultures it also prevented the proliferation and activation of sensitized CBA/J or F1 effector cell precursors. Other mAb specific for MHC class II gene products, but not associated with disease susceptibility, expressed by CBA/J (I-Ek) or F1 (I-Ad) mice (14-4-4S or MK-D6 respectively), also prevented in vivo sensitization, but did not block in vitro activation. Anti-I-Ak was also effective in preventing EAT if multiple injections of mAb were given to recipients of sensitized EAT effector cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of toxicity involving haemorrhage and cardiovascular failure, caused by parenteral administration of a soluble polyacrylate in the rat

Adverse effects, involving a combination of hypotension and widespread haemorrhages, as well as evidence of vascullar and other tissue dissociation, associated with various systemic malfunctions (cyanosis, cardiac arrhythmias, neuromuscular disorder and death) were observed in the rat, from parenteral administration of a high-molecular-weight soluble polymer, sodium polyacrylate (EN21). Experiments to elucidate the mechanism of this effect involved comparisons with a low-molecular-weight sodium polyacrylate (EN5), either drug being given to groups of 5-8 rats, male or female, in doses of 5-100 mg/kg i.v., i.p. or s.c., or up to 1000 mg/kg p.o. Effects were observed visually up to the death of the animals, and these plus survivors killed after 10 h were prosected for macroscopic and histopathological examination of internal organs. Characteristic EN21 effects were only observed in animals treated by the i.p. and i.v. routes, death occurring in 4-10 h or rapidly (1 h) after i.v. dosage. No such effects were observed from EN5 by any dose or route. There were no differences between effects in male and female animals. In rats anaesthetized with sodium pentobarbitone and cannulated for blood pressure recording (arterial and venous), no hypertensive effects were observed to explain haemorrhagic effects. Instead, i.v. and i.p. injections gave depressor effects, insidious in the latter case, with a precipitous fall only in the delayed terminal stage. Effects were accompanied by cardiac arrhythmias. Depressor effects were prevented by prior treatment of the animals with calcium chloride solution. These effects could not be evoked by EN5, nor by injection of methylcellulose solutions of equivalent high viscosity.(ABSTRACT TRUNCATED AT 250 WORDS)