CCR1-specific non-peptide antagonist: efficacy in a rabbit allograft rejection model

Area of Science:

• Immunology
• Transplantation Biology
• Pharmacology

Background:

• Acute cellular rejection in organ transplantation involves mononuclear cell infiltration.
• Chemokines like RANTES mediate leukocyte recruitment to transplanted tissues.
• RANTES acts as a potent agonist for the CC chemokine receptor CCR1.

Purpose of the Study:

• To evaluate the efficacy of the CCR1 antagonist BX 471 in a rabbit kidney transplant rejection model.
• To determine if blocking CCR1 can mitigate the inflammatory processes associated with transplant rejection.

Main Methods:

• BX 471 binding affinity and antagonist activity against rabbit CCR1 were assessed in vitro.
• Rabbit kidney transplant recipients were treated with subcutaneous slow-release pellets of BX 471.
• Survival rates, serum urea and creatinine levels, and kidney pathology were analyzed.

Main Results:

• BX 471 demonstrated high-affinity competitive antagonism of rabbit CCR1.
• BX 471 treatment significantly increased mean survival time compared to placebo (P=0.03).
• BX 471 reduced urea and creatinine levels and prevented kidney infarction, similar to cyclosporine.

Conclusions:

• BX 471 exhibits clear efficacy in preventing acute cellular rejection in a rabbit kidney transplant model.
• Blocking CCR1 with BX 471 is a viable strategy to improve transplant outcomes.
• Further investigation into BX 471 as a therapeutic agent for organ transplantation is warranted.