99mTc-Fanolesomab: affinity, pharmacokinetics and preliminary evaluation

Area of Science:

• Nuclear Medicine
• Immunology
• Diagnostic Imaging

Background:

• Accurate infection localization is crucial for effective diagnosis and treatment.
• Traditional methods like radiolabeled leukocytes have drawbacks including cost and time-intensive procedures.
• Development of novel imaging agents is essential to overcome existing diagnostic limitations.

Purpose of the Study:

• To evaluate the efficacy of anti-CD15 monoclonal antibody (NeutroSpec) labeled with technetium-99m for localizing bacterial infections.
• To compare NeutroSpec with existing radiolabeled agents, focusing on diagnostic accuracy and procedural advantages.
• To assess the safety and specificity of NeutroSpec in clinical settings.

Main Methods:

• Screening of ten monoclonal antibodies for high affinity to neutrophils.
• Selection and labeling of anti-CD15 antibody (NeutroSpec) with technetium-99m.
• Evaluation of NeutroSpec's binding affinity, specificity, and performance in diagnostic imaging studies.

Main Results:

• Anti-CD15 antibody demonstrated high binding affinity (Kd=1.6x10(-11) M) to human neutrophils.
• NeutroSpec labeling with (99m)Tc offers advantages over in vitro labeled white blood cells, including reduced procedure time.
• The antibody showed high specificity for neutrophils with minimal expression on other blood cells, and a favorable safety profile in patients.

Conclusions:

• NeutroSpec represents a significant advancement in nuclear imaging for infection localization.
• Its high specificity, favorable safety profile, and simplified imaging protocol make it a valuable diagnostic tool.
• NeutroSpec overcomes key limitations of previous radiopharmaceuticals, improving diagnostic efficiency and patient care.