Patient Perspectives on Solid Organ Transplantation From Donors With Hepatitis C Viremia to Recipients Without Hepatitis C Viremia.

Background: Organ transplantation from donors with hepatitis C viremia (HCV) to recipients without HCV (HCV D+/R-) has excellent medical outcomes. Less is known about the psychosocial impact and experiences of HCV D+/R- recipients, particularly outside of clinical trials. Methods: We conducted in-depth, semistructured interviews with 24 HCV D+/R- recipients (kidney, n = 8; lung, n = 7; liver, n = 5; heart, n = 3; simultaneous heart and kidney, n = 1) who received transplants outside of clinical trials and were treated for HCV after transplant to assess their experiences and perspectives. We used thematic analysis to analyze the interviews. Results: Interviewees' reasons for accepting an HCV D + organ were based on perceived benefits and confidence in the effectiveness of HCV treatment. The majority (62%) received HCV treatment within 1 month after transplant (range, 1 day-2 months). Most interviewees reported positive transplant outcomes, including reduced wait times and improved survival, health, physical activity, and quality of life. Overall, themes and experiences did not differ significantly between different organ transplant types. Generally, interviewees did not perceive stigma from those aware of the HCV D+ transplant; yet, disclosure was selective and a few recipients reported concerns from family members about posttransplant HCV transmission risk. Other common concerns included treatment costs and delays, which were not always anticipated by recipients. Conclusions: Our findings suggest that HCV D+/R- kidney, liver, and heart and lung transplant recipients outside of clinical trials had overall positive experiences. However, HCV transmission risk, treatments costs, and treatment delays were a source of concern that might be mitigated with targeted pretransplant education.

Loss of chondroitin sulfate proteoglycan sulfation allows delayed sympathetic reinnervation after cardiac ischemia-reperfusion.

Sympathetic nerve loss in the heart predicts the risk of ventricular arrhythmias after myocardial infarction (MI) in patients. Sympathetic denervation after cardiac ischemia-reperfusion is sustained by matrix components chondroitin sulfate proteoglycans (CSPGs) in the cardiac scar. We showed that 4,6-sulfation of CSPGs was critical for preventing nerve growth into the scar. Promoting early reinnervation with therapeutics reduces arrhythmias during the first 2 weeks after MI, but the longer-term consequences of restoring innervation are unknown. Therefore, we asked if the beneficial effects of early reinnervation were sustained. We compared cardiac function and arrhythmia susceptibility 40 days after MI in mice treated on Days 3-10 with vehicle or with intracellular sigma peptide to restore innervation. Surprisingly, both groups had normal innervation density in the cardiac scar 40 days after MI, indicating delayed reinnervation of the infarct in vehicle-treated mice. That coincided with similar cardiac function and arrhythmia susceptibility in the two groups. We investigated the mechanism allowing delayed reinnervation of the cardiac scar. We found that CSPG 4,6-sulfation, which is elevated early after ischemia-reperfusion, was reduced to control levels allowing reinnervation of the infarct. Thus, remodeling of extracellular matrix weeks after injury leads to remodeling of sympathetic neurons in the heart.

Patients' Experiences With HIV-positive to HIV-positive Organ Transplantation.

BACKGROUND: HIV+ donor (HIV D+) to HIV+ recipient (HIV R+) transplantation involves ethical considerations related to safety, consent, stigma, and privacy, which could be better understood through studying patients' actual experiences. METHODS: We interviewed kidney and liver transplant recipients enrolled in clinical trials evaluating HIV D+/R+ transplantation at 4 centers regarding their decision-making process, the informed consent process, and posttransplant experiences. Participants were interviewed at-transplant (≤3 wk after transplant), posttransplant (≥3 mo after transplant), or both time points. Interviews were analyzed thematically using constant comparison of inductive and deductive coding. RESULTS: We conducted 35 interviews with 22 recipients (15 at-transplant; 20 posttransplant; 13 both time points; 85% participation). Participants accepted HIV D+ organs because of perceived benefits and situational factors that increased their confidence in the trials and outweighed perceived clinical and social risks. Participants reported positive experiences with the consent process and the trial. Some described HIV-related stigma and emphasized the need for privacy; others believed HIV D+/R+ transplantation could help combat such stigma. There were some indications of possible therapeutic misestimation (overestimation of benefits or underestimation of risks of a study). Some participants believed that HIV+ transplant candidates were unable to receive HIV-noninfected donor organs. CONCLUSIONS: Despite overall positive experiences, some ethical concerns remain that should be mitigated going forward. For instance, based on our findings, targeted education for HIV+ transplant candidates regarding available treatment options and for transplant teams regarding privacy and stigma concerns would be beneficial.

124I-HuCC49deltaCH2 for TAG-72 antigen-directed positron emission tomography (PET) imaging of LS174T colon adenocarcinoma tumor implants in xenograft mice: preliminary results.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) is widely used in diagnostic cancer imaging. However, the use of 18F-FDG in PET-based imaging is limited by its specificity and sensitivity. In contrast, anti-TAG (tumor associated glycoprotein)-72 monoclonal antibodies are highly specific for binding to a variety of adenocarcinomas, including colorectal cancer. The aim of this preliminary study was to evaluate a complimentary determining region (CDR)-grafted humanized CH2-domain-deleted anti-TAG-72 monoclonal antibody (HuCC49deltaCH2), radiolabeled with iodine-124 (124I), as an antigen-directed and cancer-specific targeting agent for PET-based imaging. METHODS: HuCC49deltaCH2 was radiolabeled with 124I. Subcutaneous tumor implants of LS174T colon adenocarcinoma cells, which express TAG-72 antigen, were grown on athymic Nu/Nu nude mice as the xenograft model. Intravascular (i.v.) and intraperitoneal (i.p.) administration of 124I-HuCC49deltaCH2 was then evaluated in this xenograft mouse model at various time points from approximately 1 hour to 24 hours after injection using microPET imaging. This was compared to i.v. injection of 18F-FDG in the same xenograft mouse model using microPET imaging at 50 minutes after injection. RESULTS: At approximately 1 hour after i.v. injection, 124I-HuCC49deltaCH2 was distributed within the systemic circulation, while at approximately 1 hour after i.p. injection, 124I-HuCC49deltaCH2 was distributed within the peritoneal cavity. At time points from 18 hours to 24 hours after i.v. and i.p. injection, 124I-HuCC49deltaCH2 demonstrated a significantly increased level of specific localization to LS174T tumor implants (p=0.001) when compared to the 1 hour images. In contrast, approximately 50 minutes after i.v. injection, 18F-FDG failed to demonstrate any increased level of specific localization to a LS174T tumor implant, but showed the propensity toward more nonspecific uptake within the heart, Harderian glands of the bony orbits of the eyes, brown fat of the posterior neck, kidneys, and bladder. CONCLUSIONS: On microPET imaging, 124I-HuCC49deltaCH2 demonstrates an increased level of specific localization to tumor implants of LS174T colon adenocarcinoma cells in the xenograft mouse model on delayed imaging, while 18F-FDG failed to demonstrate this. The antigen-directed and cancer-specific 124I-radiolabled anti-TAG-72 monoclonal antibody conjugate, 124I-HuCC49deltaCH2, holds future potential for use in human clinical trials for preoperative, intraoperative, and postoperative PET-based imaging strategies, including fused-modality PET-based imaging platforms.

Near-infrared fluorescence labeled anti-TAG-72 monoclonal antibodies for tumor imaging in colorectal cancer xenograft mice.

Anti-TAG-72 monoclonal antibodies target the tumor-associated glycoprotein (TAG)-72 in various solid tumors. This study evaluated the use of anti-TAG-72 monoclonal antibodies, both murine CC49 and humanized CC49 (HuCC49deltaCH2), for near-infrared fluorescent (NIR) tumor imaging in colorectal cancer xenograft models. The murine CC49 and HuCC49deltaCH2 were conjugated with Cy7 monofunctional N-hydroxysuccinimide ester (Cy7-NHS). Both in vitro and in vivo anti-TAG-72 antibody binding studies were performed. The in vitro study utilized the human colon adenocarcinoma cell line LS174T that was incubated with Cy7, antibody-Cy7 conjugates, or excessive murine CC49 followed by the antibody-Cy7 conjugates and was imaged by fluorescence microscopy. The in vivo study utilized xenograft mice, bearing LS174T subcutaneous tumor implants, that received tail vein injections of Cy7, murine CC49-Cy7, HuCC49deltaCH2-Cy7, or nonspecific IgG-Cy7 and were imaged by the Xenogen IVIS 100 system from 15 min to 288 h. The biodistribution of the fluorescence labeled antibodies was determined by imaging the dissected tissues. The in vitro study revealed that the antibody-Cy7 conjugates bound to LS174T cells and were blocked by excessive murine CC49. The in vivo study demonstrated that murine CC49 achieved a tumor/blood ratio of 15 at 96 h postinjection. In comparison, HuCC49deltaCH2-Cy7 cleared much faster than murine CC49-Cy7 from the xenograft mice, and HuCC49deltaCH2-Cy7 achieved a tumor/blood ratio of 12 at 18 h postinjection. In contrast, Cy7 and Cy7 labeled nonspecific IgG resulted in no demonstrable tumor accumulation. When mice were injected with excessive unlabeled murine CC49 at 6 h before the injection of murine CC49-Cy7 or HuCC49deltaCH2-Cy7, both the intensity and retention time of the fluorescence from the tumor were reduced. In summary, the Cy7 labeled murine CC49 and HuCC49deltaCH2 demonstrate tumor-targeting capabilities in living colorectal cancer xenograft mice and provide an alternative modality for tumor imaging.

Perioperative (18)F-fluorodeoxyglucose-guided imaging using the becquerel as a quantitative measure for optimizing surgical resection in patients with advanced malignancy.

BACKGROUND: (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) scanning is a widely accepted preoperative tumor imaging modality. Herein, we evaluate the becquerel (Bq) as a potential novel quantitative PET measure for application of surgical specimen imaging. METHODS: Retrospectively, PET-avid lesions that could be followed from preoperative imaging, confidently identified in the operating room, imaged ex vivo, and correlated with histopathology were included in this study. Bq counts from both in vivo (preoperative) and ex vivo (surgical specimen) PET/CT images were measured and correlated with histopathology. RESULTS: Fifty-five PET-avid lesions in 37 patients were included. Forty-six of 55 PET-avid lesions identified were found to contain malignancy on histopathology. Mean Bq counts for the PET-avid lesions were significantly higher that the adjacent PET-nonavid areas (background) within both in vivo and ex vivo imaging (P < .001 and P < .001, respectively). When analyzing all 55 lesions, we found significant increases in Bq levels. PET-avid lesions from in vivo to ex vivo images (P < .001) without significant increases in Bq levels in PET-nonavid lesions from in vivo to ex vivo images (P = .06). When comparing Bq levels between the 2 groups (malignant and benign), we found significantly higher Bq counts in the malignant group on in vivo imaging (P = .02) as well as significantly lower Bq counts in FDG-nonavid areas on ex vivo imaging (P = .04) within the malignant group. Significant differences in PET-avid to PET-nonavid Becquerels ratios within both in vivo and ex vivo images (P = .004, P = .002 respectively) were found, with ex vivo ratio being significantly higher (P < .001). CONCLUSIONS: (18)F-FDG PET/CT imaging using Bqs is the potential to discern malignant lesions from benign tissues within both in vivo and ex vivo scans.

A novel approach to positron emission tomography in lung cancer.

18F-fluorodeoxyglucose positron emission tomography-computed tomography is integral to the staging of lung cancer. We describe the combined use of diagnostic preoperative 18F-fluorodeoxyglucose positron emission tomography-computed tomography, intraoperative 18F-fluorodeoxyglucose handheld gamma probe detection, and immediate postoperative 18F-fluorodeoxyglucose positron emission tomography-computed tomography patient and specimen imaging for improved staging and determination of adequacy of mediastinal lymph node dissection.