Hyperimmune egg-based IgY-rich formulations as adjuvant therapy in a murine model of urinary tract infection

AIM: Evaluating the efficacy of two Immunoglobulin Y-rich products using a murine model of Escherichia coli urinary tract infection. BACKGROUND: Uropathogenic Escherichia coli is responsible for the majority of urinary tract infections (UTIs), with a recurrence rate of 25% within 6 months of treatment. METHOD: Thirty female C57BL/6 mice susceptible to uropathogenic Escherichia coli (UPEC) DSM 103538 strain were equally divided into three groups: Control (C), ImunoinstantG (IG), and Imunoinstant Anti-Escherichia coli (IE). A 30 μL inoculum of UPEC containing 5 × 10⁷ CFU was administered intravesical to induce infection. Each experimental group received a dose/kg equivalent to an adult human weighing 70 kg (0.9 mg IgY/mouse in 0.35 mL) administered via gavage. The control group received the same volume of drinking water. The products were administered daily for 22 days, starting 7 days before infection. Bacterial load in urine was evaluated on days 7, 10, and 15. RESULTS: The results showed a significant reduction (p < 0.05) in the number of CFUs of UPEC in the treated groups compared to the control group. On day 7, the bacterial load was 1.8 × 10⁶ CFU/mL in group C, 1.9 × 10⁵ CFU/mL in group IG, and 1.6 × 10⁵ CFU/mL in group IA, while on day 15 the bacterial load was 3.2 × 10⁴ CFU/mL, 6.0 × 10³ CFU/mL, and 4.2 × 10³ CFU/mL respectively. CONCLUSION: The tested products significantly reduced bacterial load with no notable differences between them, suggesting both could be effective alternatives for preventing and treating UTIs.