Immunomanipulation of appetite and body temperature through the functional mimicry of leptin.

Abstract

OBJECTIVE:

Although current obesity therapies produce some benefits, there is a need for new strategies to treat obesity. A novel proposal is the use of anti-idiotypic antibodies as surrogate ligands or hormones. These anti-idiotypic antibodies carry an internal motif that imitates or mimics an epitope in the antigen (i.e., hormone or ligand). Thus, anti-idiotypic antibodies to several ligands may mimic them in transducing signals when binding to their receptors.

RESEARCH METHODS AND PROCEDURES:

We developed an anti-idiotypic polyclonal antibody against the region of a leptin monoclonal antibody that competitively binds leptin, mimicking the active site structure of leptin. To test whether our anti-idiotype could also reproduce leptin functions, we examined food intake, body weight, and colonic temperature in male Wistar rats (n = 9) in response to intracerebroventricular administration of the leptin anti-idiotype.

RESULTS:

Our leptin anti-idiotype induced a significant reduction in food intake coupled with an increase in body temperature comparable to that of leptin. That is, the intracerebroventricular administration of 8.0 microg of leptin anti-idiotype or 5.0 microg leptin significantly increased colonic temperature (Delta 1.9 +/- 0.11 degrees C and Delta 1.7 +/- 0.12 degrees C, respectively). In addition, both decreased 24-hour food intake (-26.4 +/- 2.4% and -21.9 +/- 2.2%) compared with the control. The gain in body weight was also decreased by acute administration of the anti-idiotype (-1.4 +/- 0.28%) and leptin (-1.1 +/- 0.17%) vs. the phosphate-buffered saline control (1.3 +/- 0.15%).

DISCUSSION:

These studies revealed that the leptin anti-idiotype inhibited food intake and enhanced heat production, mimicking leptin's central actions.

• Authors: Brant A De Fanti, Fermin I Milagro, Oscar Lamas, Eduardo Martínez-Ansó, J Alfredo Martínez
• Journal: Obesity research (Obes Res) Vol. 10 Issue 8 Pg. 833-7 (Aug 2002) ISSN: 1071-7323 [Print] United States
• PMID: 12181393 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antibodies, Anti-Idiotypic
• Antibodies, Monoclonal
• Leptin

Topics

• Animals
• Antibodies, Anti-Idiotypic (administration & dosage, pharmacology)
• Antibodies, Monoclonal (immunology)
• Appetite (drug effects)
• Body Temperature (drug effects)
• Body Weight (drug effects)
• Colon
• Eating (drug effects)
• Injections, Intraventricular
• Leptin (immunology, physiology)
• Male
• Rats
• Rats, Wistar