T2* time in the placentas in APS and the foetal brains in APS and PTB mice injected with USPIOs was not different from USPIO-treated control mice, indicating that phagocytic cells do not have a significant role in the decreased T2* times observed in APS and PTB mice treated with USPIO-conjugated anti-C3-treated antibodies. Here, C3 is linked to autoimmune polyendocrinopathy.