Non-invasive molecular imaging of inflammatory macrophages in allograft rejection.

BackgroundMacrophages represent a critical cell type in host defense, development and homeostasis. The ability to image non-invasively pro-inflammatory macrophage infiltrate into a transplanted organ may provide an additional tool for the monitoring of the immune response of the recipient against the donor graft. We therefore decided to image in vivo sialoadhesin (Sn, Siglec 1 or CD169) using anti-Sn mAb (SER-4) directly radiolabelled with (99m)Tc pertechnetate.MethodsWe used a heterotopic heart transplantation model where allogeneic or syngeneic heart grafts were transplanted into the abdomen of recipients. In vivo nanosingle-photon emission computed tomography (SPECT/CT) imaging was performed 7 days post transplantation followed by biodistribution and histology.ResultsIn wild-type mice, the majority of (99m)Tc-SER-4 monoclonal antibody cleared from the blood with a half-life of 167 min and was located predominantly on Sn(+) tissues in the spleen, liver and bone marrow. The biodistribution in the transplantation experiments confirmed data derived from the non-invasive SPECT/CT images, with significantly higher levels of (99m)Tc-SER-4 observed in allogeneic grafts (9.4 (±2.7) %ID/g) compared to syngeneic grafts (4.3 (±10.3) %ID/g) (p = 0.0022) or in mice which received allogeneic grafts injected with (99m)Tc-IgG isotype control (5.9 (±0.6) %ID/g) (p = 0.0185). The transplanted heart to blood ratio was also significantly higher in recipients with allogeneic grafts receiving (99m)Tc-SER-4 as compared to recipients with syngeneic grafts (p = 0.000004) or recipients with allogeneic grafts receiving (99m)Tc-IgG isotype (p = 0.000002).ConclusionsHere, we demonstrate that imaging of Sn(+) macrophages in inflammation may provide an important additional and non-invasive tool for the monitoring of the pathophysiology of cellular immunity in a transplant model

Photoluminescence of transparent strontium–barium–niobate-doped silica nanocomposites

Author name used in this publication: C. L. MakAuthor name used in this publication: K. H. Wong2001-2002 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Effects of postdeposition annealing on the dielectric properties of antiferroelectric lanthanum-doped lead zirconate stannate titanate thin films derived from pulsed laser deposition

Author name used in this publication: K. H. Wong2004-2005 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Tuning the Resonant Frequency and Damping of an Electromagnetic Energy Harvester Using Power Electronics

Accepted versio

Time-resolved photoluminescence of barium titanate ultrafine powders

Author name used in this publication: C. L. MakAuthor name used in this publication: K. H. Wong2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Proximal wrist extensor tendinopathy

Proximal wrist extensor tendinopathy, which is also known as tennis elbow, is pain at or just distal to the lateral humeral epicondyle within the proximal wrist extensor tendon. It occurs commonly in certain athletes but can also occur in people with jobs that require repetitive movements of the hand and upper limb. In most cases the tendon involved shows no signs of inflammation or tendonitis, but instead shows fibroblasts, vascular hyperplasia, and disorganized collagen. Diagnosis is often made by history and physical exam alone. Most people respond to conservative measures including activity modification, analgesics, manipulation of tissue, and exercise. In some cases, an injection of corticosteroid or botulinum toxin may be used. Surgery is rarely needed