Imaging mouse lung allograft rejection with (1)H MRI

Area of Science:

• Transplantation immunology
• Medical imaging
• Pulmonary research

Background:

• Acute cellular rejection is a major challenge in lung transplantation.
• Noninvasive monitoring methods are crucial for assessing allograft health and treatment efficacy.
• Magnetic Resonance Imaging (MRI) offers potential for longitudinal, noninvasive assessment.

Purpose of the Study:

• To establish MRI as a method for characterizing acute cellular rejection in mouse orthotopic lung allografts.
• To demonstrate the utility of longitudinal MRI monitoring for assessing allograft rejection.
• To correlate MRI findings with histopathological evidence of rejection.

Main Methods:

• Orthotopic lung transplantation performed in mice (Balb/c to C57BL/6).
• Groups included control-Ig and anti-CD4/anti-CD8 treated mice.
• Two-dimensional gradient-echo MRI sequences acquired at postoperative days 3, 7, and 14.
• Lung volume, parenchymal signal, and lung compliance were measured.

Main Results:

• Control-Ig allografts showed increased normalized parenchymal signal over time (P < 0.05), correlating with rejection.
• Lung compliance significantly decreased in control-Ig allografts (P < 0.05).
• Anti-CD4/anti-CD8 treatment maintained stable lung compliance.

Conclusions:

• MRI-based measurements of lung parenchymal signal and compliance can monitor lung allograft rejection.
• Longitudinal MRI imaging provides insights into the temporal dynamics of rejection and treatment response.
• This noninvasive approach aids in understanding individual allograft rejection trajectories.