Otto Kollmar

Surgical-site infection after abdominal wall closure with triclosan-impregnated polydioxanone sutures: Results of a randomized clinical pathway facilitated trial (NCT00998907)

BACKGROUND Wound infections after abdominal surgery are still frequent types of nosocomial infections. Suture materials might serve as a vehicle for mechanical transport of bacteria into the surgical wound. To prevent the contamination of suture material in surgical wounds, triclosan-coated suture materials with antibacterial activity was developed. We here report a prospective randomized pathway controlled trial investigating the effect of triclosan impregnation of polydioxanone sutures used for abdominal wall closure on the rate of surgical-site infections. PATIENTS AND METHODS A total of 856 patients included in this trial underwent a standardized clinical pathway documented abdominal wall closure after abdominal surgery. Patients were randomized to have the fascia closed with either a 2-0 polydioxanone loop or a triclosan impregnated 2-0 polydioxanone loop. The primary outcome was the number of wound infections. Risk factors for poor wound healing were collected prospectively to compare the two groups. RESULTS When a PDS loop suture for abdominal wall closure was used, 42 (11.3%) patients with wound infections were detected. The number of patients with wound infections decreased significantly to 31 when the PDS plus for abdominal wall closure was used (6.4%, P < .05). Other risk factors for the development of side infections were comparably in the two groups. CONCLUSION This clinical pathway facilitated trial shows that triclosan impregnation of a 2-0 polydioxanone closing suture can decrease wound infections in patients having a laparotomy for general and abdominal vascular procedures.

Hepatic resection of non-colorectal and non-neuroendocrine liver metastases – Survival benefit for patients with non-gastrointestinal primary cancers – A case-controlled study

PURPOSE Whereas resection of colorectal liver metastases is gold standard, there is an ongoing debate on benefit of resection of non-colorectal (NCRC) and non-neuroendocrine (NNEC) liver metastases. METHODS The potential survival benefit of patients undergoing resection of NCRC or NNEC liver metastases was investigated. Data from a prospectively maintained database were reviewed over a 7-year period. Kaplan-Meier method was used for the evaluation of outcome following resection. RESULTS 101 patients underwent 116 surgical procedures for synchronous and metachronous NCRC or NNEC liver metastases with a morbidity of 23% and a mortality of ∼1%. 11 patients underwent repeated liver resection procedures. Overall 5-year survival after liver resection was 30% depending on primary tumour site. Median survival was significantly increased after resection of hepatic metastases from non-gastrointestinal primaries compared to gastrointestinal primaries. Resection of hepatic metastases from non-gastrointestinal primaries resulted in significantly increased median survival compared to exploration only. Patients with hepatic metastases from gastrointestinal primaries did not benefit from hepatic surgery. CONCLUSION Hepatic resection for liver metastases from NCRC or NNEC cancers is a save treatment procedure. However, the decision to perform surgery should depend on the primary cancer. Especially patients with liver metastases from non-gastrointestinal primaries profit from hepatic surgery.

Graft-derived cell-free DNA, a noninvasive early rejection and graft damage marker in liver transplantation: A prospective, observational, multicenter cohort study

Background Graft-derived cell-free DNA (GcfDNA), which is released into the blood stream by necrotic and apoptotic cells, is a promising noninvasive organ integrity biomarker. In liver transplantation (LTx), neither conventional liver function tests (LTFs) nor immunosuppressive drug monitoring are very effective for rejection monitoring. We therefore hypothesized that the quantitative measurement of donor-derived cell-free DNA (cfDNA) would have independent value for the assessment of graft integrity, including damage from acute rejection. Methods and findings Traditional LFTs were performed and plasma GcfDNA was monitored in 115 adults post-LTx at three German transplant centers as part of a prospective, observational, multicenter cohort trial. GcfDNA percentage (graft cfDNA/total cfDNA) was measured using droplet digital PCR (ddPCR), based on a limited number of predefined single nucleotide polymorphisms, enabling same-day turn-around. The same method was used to quantify blood microchimerism. GcfDNA was increased >50% on day 1 post-LTx, presumably from ischemia/reperfusion damage, but rapidly declined in patients without graft injury within 7 to 10 d to a median <10%, where it remained for the 1-y observation period. Of 115 patients, 107 provided samples that met preestablished criteria. In 31 samples taken from 17 patients during biopsy-proven acute rejection episodes, the percentage of GcfDNA was elevated substantially (median 29.6%, 95% CI 23.6%–41.0%) compared with that in 282 samples from 88 patients during stable periods (median 3.3%, 95% CI 2.9%–3.7%; p < 0.001). Only slightly higher values (median 5.9%, 95% CI 4.4%–10.3%) were found in 68 samples from 17 hepatitis C virus (HCV)–positive, rejection-free patients. LFTs had low overall correlations (r = 0.28–0.62) with GcfDNA and showed greater overlap between patient subgroups, especially between acute rejection and HCV+ patients. Multivariable logistic regression modeling demonstrated that GcfDNA provided additional LFT-independent information on graft integrity. Diagnostic sensitivity and specificity were 90.3% (95% CI 74.2%–98.0%) and 92.9% (95% CI 89.3%–95.6%), respectively, for GcfDNA at a threshold value of 10%. The area under the receiver operator characteristic curve was higher for GcfDNA (97.1%, 95% CI 93.4%–100%) than for same-day conventional LFTs (AST: 95.7%; ALT: 95.2%; γ-GT: 94.5%; bilirubin: 82.6%). An evaluation of microchimerism revealed that the maximum donor DNA in circulating white blood cells was only 0.068%. GcfDNA percentage can be influenced by major changes in host cfDNA (e.g., due to leukopenia or leukocytosis). One limitation of our study is that exact time-matched GcfDNA and LFT samples were not available for all patient visits. Conclusions In this study, determination of GcfDNA in plasma by ddPCR allowed for earlier and more sensitive discrimination of acute rejection in LTx patients as compared with conventional LFTs. Potential blood microchimerism was quantitatively low and had no significant influence on GcfDNA value. Further research, which should ideally include protocol biopsies, will be needed to establish the practical value of GcfDNA measurements in the management of LTx patients.

Oral findings and dental behaviour before and after liver transplantation – a single-centre cross-sectional study

OBJECTIVE The aim of this single-centre, cross-sectional study was to evaluate dental, periodontal and mycological findings, as well as oral behaviour, in patients before (pre-LTx) and after (post-LTx) liver transplantation. METHODS A total of 47 patients pre-LTx and 119 patients post-LTx were asked to participate. Oral health behaviour was assessed using a standardised questionnaire. Oral examinations included dental [decayed, missing and filled teeth (DMFT) index] and periodontal [papillary bleeding index (PBI), periodontal probing depth (PPD) and clinical attachment loss (CAL)] findings. For Candida screening, swabs from the oral mucosa were cultured. Statistical analysis was performed using the Students t-test or the Mann-Whitney U-test, depending on whether or not the data followed a normal distribution; Fishers exact test was also performed. The significance level was α = 5%. RESULTS A total of 110 patients were included (pre-LTx, n = 35; post-LTx, n = 75). Different patients were investigated in the post-LTx and pre-LTx groups. Lack of use of supplemental oral-hygiene aids was noted. Between-group comparisons failed to find significant overall differences in DMFT and periodontal status. The post-LTx group showed fewer decayed teeth (P = 0.03). A total of 86% of patients pre-LTx and 84% of patients post-LTx were found to need dental treatment, and 60% of patients pre-LTx and 55% of patients post-LTx showed a need for periodontal treatment. The prevalence of Candida albicans was high; however, there were no statistically significant differences between the groups in regard to fungal infection. CONCLUSION Improved dental care pre- and post-transplant, including screening for fungal infections, is recommended to avoid systemic infections in LTx patients. Increased attention to oral health care, and interdisciplinary collaboration to provide guidance, is needed to improve the oral health of patients before and after LTx.

Intrahepatic cholangiocarcinoma in a transplant liver - selective internal radiation therapy followed by right hemihepatectomy: report of a case

Intra- or extrahepatic cholangiocarcinomas are the second most common primary liver malignancies behind hepatocellular carcinoma. Whereas the incidence for intrahepatic cholangiocarcinoma is rising, the occurrence of extrahepatic cholangiocarcinoma is trending downwards. The treatment of choice for intrahepatic cholangiocarcinoma remains liver resection. However, a case of liver resection after selective internal radiation therapy in order to treat a recurrent intrahepatic cholangiocarcinoma in a transplant liver is unknown in the literature so far. Herein, we present a case of a patient undergoing liver transplantation for Wilson’s disease with an accidental finding of an intrahepatic cholangiocarcinoma within the explanted liver. Due to a recurrent intrahepatic cholangiocarcinoma after liver transplantation, a selective internal radiation therapy with yttrium-90 microspheres was performed followed by right hemihepatectomy. Four years later, the patient is tumor-free and in a healthy condition.

[A totally implantable venous access device. Implantation in general or local anaesthesia? A retrospective cost analysis].

BACKGROUND Implantation of venous access port systems can be performed in local or general anesthesia. In spite of the increasing rate of interventionally implanted systems, the surgical cut-down represents a safe alternative. Thus, the question arises whether--in context to the increasing health-economic pressure--open implantation in general anesthesia is still a feasible alternative to implantation in local anesthesia regarding OR efficiency and costs. PATIENTS AND METHODS In a retrospective analysis, 993 patients receiving a totally implantable venous access device between 2001 and 2007 were evaluated regarding OR utilization, turnover times, intraoperative data and costs. Implantations in local (LA) and general anesthesia (GA) were compared. RESULTS GA was performed in 762 cases (76.6 %), LA was performed in 231 patients (23.3 %). Mean operation time was similar in both groups (LA 47.27 +/- 1.40 min vs. GA 45.41 +/- 0.75 min, p = 0.244). Patients receiving local anesthesia had a significantly shorter stay in the OR unit (LA 95.9 +/- 1.78 min vs. GA 105.92 +/- 0.92 min; p < 0.001). Specifically, the time from arrival in the operating room to surgical cut (LA 39.57 +/- 0.69 min vs. GA 50.46 +/- 0.52 min; p < 0.001) was shorter in the LA group. Personnel and material costs were significantly lower in the LA group compared with the GA group (LA: 400.72 +/- 8.25 euro vs. GA: 482.86 +/- 6.23 euro; p < 0.001) Blood loss as well as duration and dose of radiation were similar in both groups. CONCLUSIONS Our study shows that implantation of totally implantable venous access port systems in local anesthesia is superior in comparison to the implantation under general anesthesia regarding procedural times in the OR unit and costs. With the same operation duration, but less personnel and material expenditure, implantation in local anesthesia offers a potential economic advantage by permitting faster changing times. Implantation in GA only should be performed at a special request by the patient or in difficult venous conditions.

Application of capillary immunoelectrophoresis revealed an age- and gender-dependent regulated expression of PrPC in liver

The cellular prion protein (PrPC) is a glycoprotein, anchored to the plasma membrane and abundantly expressed in the central nervous system. The expression of PrPC in the peripheral tissues is low and only little information is available on its functions in the nonneuronal tissues. The antioxidant function of PrPC during the activation of hepatic stellate cells has already been reported. Therefore, the aim of the study was to expand our knowledge on the functions of PrPC by detailed characterization of its expressional profile in the liver. In a combined strategy by using capillary immunoelectrophoresis and standard techniques, we have shown a sexually dimorphic expression of PrPC in mice and human liver tissues. Further, we showed a significant age‐dependent upregulation of PrPC expression in the liver of 14‐ and 9‐month‐old mice as compared to 3 months of age. Therefore, this study may provide new insights into the gender‐specific role of PrPC in the liver, which may further be linked to its protective role against oxidative stress during aging. In addition, the current study also shows an application of immunoelectrophoresis with a low coefficient of variation to analyze the miniscule amount of PrPC in the mouse liver tissue.

Association of time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected bacteria of patients after solid organ transplantation

Background Aim of this study was to investigate the association of the time under immunosuppression and different immunosuppressive medication on periodontal parameters and selected periodontal pathogenic bacteria of immunosuppressed patients after solid organ transplantation (SOT). Material and Methods 169 Patients after SOT (lung, liver or kidney) were included and divided into subgroups according their time under (0-1, 1-3, 3-6, 6-10 and >10 years) and form of immunosuppression (Tacrolimus, Cyclosporine, Mycophenolate, Glucocorticoids, Sirolimus and monotherapy vs. combination). Periodontal probing depth (PPD) and clinical attachment loss (CAL) were assessed. Periodontal disease severity was classified as healthy/mild, moderate or severe periodontitis. Subgingival biofilm samples were investigated for eleven selected potentially periodontal pathogenic bacteria using polymerasechainreaction. Results The mean PPD and CAL as well as prevalence of Treponema denticola and Capnocytophaga species was shown to be different but heterogeneous depending on time under immunosuppression (p<0.05). Furthermore, only the medication with Cyclosporine was found to show worse periodontal condition compared to patients without Cyclosporine (p<0.05). Prevalence of Porphyromonas gingivalis, Tannerella forsythia and Fusobacterium nucleatum was reduced and prevalence of Parvimonas micra and Capnocytophaga species was increased in patients under immunosuppression with Glucocorticoids, Mycophenolate as well as combination therapy. Conclusions Time under and form of immunosuppression might have an impact on the clinical periodontal and microbiological parameters of patients after SOT. Patients under Cyclosporine medication should receive increased attention. Differences in subgingival biofilm, but not in clinical parameters were found for Glucocorticoids, Mycophenolate and combination therapy, making the clinical relevance of this finding unclear. Key words:Immunosuppression, organ transplantation, periodontitis, periodontal bacteria.

Simultaneous resection of primary colorectal cancer and synchronous liver metastases is associated with a high cardiovascular complication rate

SummaryBackgroundOptimal timing of liver surgery for synchronous metastases regarding a simultaneous or two-staged procedure is still controversially discussed. As randomized controlled trials are ethically disputable due to potential advantages of the simultaneous approach, the following matched pair analysis was performed to investigate feasibility and short-term outcome of the additional simultaneous hepatic approach compared to colorectal surgery alone.MethodsA total of 74 patients undergoing simultaneous resection of primary colorectal cancer and synchronous liver metastases (CRC + LM) were individually case matched with patients receiving only colorectal surgery for Union for International Cancer Control (UICC) stage I-III cancer (CRC) according to: age, gender, American Society of Anesthesiologists (ASA) score, location, and T-stage of the primary tumor. Postoperative complications and risk factors for morbidity and mortality were analyzed retrospectively using univariate, multivariate, and binary logistic regression analyses.ResultsAccording to matching criteria both groups showed no differences regarding demographics and operative techniques for the primary colorectal tumor. In the CRC + LM group 4 major hepatectomies, 7 anatomic, 43 nonanatomic and 20 multiple nonanatomic resections were performed. Inhospital mortality (CRC vs. CRC + LM) was 2.7 versus 4.1 % and overall morbidity was 33.8 versus 35.1 %, respectively. Cardiovascular complications were significantly higher in the CRC + LM than in the CRC group (13.5 vs. 2.7 %). Multivariate analysis revealed that not simultaneous resection procedure but presence of chronic pulmonary disease was an independent risk factor.ConclusionsSimultaneous resection procedures can be recommended in almost all patients without chronic pulmonary disease as well as chronic heart disease. Careful precautions, especially in patients with chronic pulmonary diseases, should be taken to avoid a high possibility of postoperative cardiovascular complications.

Graft-Derived Cell-Free DNA (GcfDNA) as a Sensitive Measure of Individual Graft Integrity After Liver Transplantation.: Abstract# A7

A8 Exosomes in Human Bile for the Assessment of Transplanted Liver in the Early Postoperative Period. D. Yoshii,1 M. Mitsuhashi,2 T. Murokawa,1 K. Asonuma,1 Y. Inomata.1 1Transplantation and Pediatric Surgery, Kumamoto University Hospital, Kumamoto, Japan; 2Hitachi Chemical Research Center, Irvine. Background: After liver transplantation, transplanted liver undergoes various clinical problems. It is not always easy to make an accurate diagnosis to develop an appropriate therapeutic plan. Liver biopsy is the last resort for diagnosis, but it is invasive, and often it is not conclusive. Thus, alternative noninvasive methods are highly anticipated. Exosomes are membranous nanovesicles of 40-100nm in size, and are secreted by a variety of cell types into blood, urine, ascites, etc. More interestingly, because exosomes are known to contain proteins, mRNAs, and microRNAs, exosomes have become an interesting biomarker in many research fi elds. The aim of this study is to explore the values of yet-to-be characterized exosomes in the bile in patients with liver transplantation. Methods: From November 2012 to June 2013, we recruited 16 cases of liver transplant recipients after institutional review board approval. Using the external drainage stent tube, which is routinely placed in every case in our facility, bile was collected at POD1-7, 14, 21, 28, or everyday in some cases. Exosomes were isolated by the fi lter device, and poly(A)+ mRNAs were purifi ed by oligo(dT)-immobilized microplate and cCNA was synthesized on the same plate. The cDNAs were used for real time polymerase chain reaction (PCR) to quantify mRNAs, such as housekeeping gene (ACTB), albumin(ALB), interleukin (IL) (1β, 2, 6, 8, 10), TNFα, FasL, IFNγ, HGF, VEGF, CD16, PRG2 and DEFA3. Results and discussion: ACTB mRNA was successfully detected from the majority of bile samples, suggesting that the bile contained exosomes, and mRNAs were securely present inside exosome. Similarly, liver-specifi c ALB mRNA was also detected in the bile exosomes, suggesting that the bile contained liver-derived exosomes. Three patients diagnosed as acute rejection expressed various mRNAs, and especially the levels of IL-8 mRNA were very prominent. Moreover, eosinophil-derived PRG2 was increased at the time of rejection, which corresponded to the eosinophil-infi ltration, a typical pathological landmark of acute rejection. Conclusions: This study suggests that biliary exosomal mRNAs are promising biomarkers for the assessment of pathological conditions of transplanted livers. DISCLOSURES: Mitsuhashi, M.: Other, Hitachi Chemical Research Center, employee of R&D company developing of diagnostics. Abstract# A9 Monocyte Presentation of Donor Antigen Predicts Acute Cellular Rejection (ACR) After Liver or Intestine Transplantation (ITx, LTx). C. Ashokkumar, M. Ningappa, B. Higgs, Q. Sun, R. Sindhi. Surgery, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA. Background: Enhanced donor alloantigen presentation by CD14+monocytes predicts or associates with ACR in small cohorts of pediatric LTx and ITx. Purpose: To evaluate the performance of monocyte alloantigen presentation for predicting biopsy-proven ACR in training-set-validation-set testing of 67 pediatric LTx and ITx. Methods: The frequency of recipient CD14+monocytes which presented donor and HLA-non-identical third-party alloantigen was measured with fl ow cytometry and expressed as a ratio termed the monocyte antigen presenting index (mAPI). An mAPI >1 implied increased donor antigen presentation relative to presentation of third-party alloantigen. A threshold mAPI associated with ACR was developed in 35 cross-sectional training set samples from children with ITx (n=11) and LTx (n=24) using logistic regression and applied to 32 samples from 26 independent LTx and 6 independent ITx recipients. Test results were also correlated with allospecifi c CD154+T-cytotoxic memory cells (CD154+TcM), which predict ACR with high sensitivity and specifi city. Results: Mean age was 5.9 years (range 0.6 to 21, n=67). Distribution of male: female gender was 38: 29, caucasian: other race was 58: 9, LTx: ITx was 50: 17, and rejector: non-rejector status was 31: 19 for LTx and 9: 8 for ITx recipients. Rejectors were sampled at a mean interval of 5.4 days (range 0 to 38) before biopsy-proven ACR. A signifi cantly greater mAPI was seen among rejectors compared with non-rejectors 0.6±0.7 vs 4.4±6.2, p=0.003. For predicting ACR, the performance of an mAPI ≥ 1.2, developed in 35 training set samples was measured as sensitivity, specifi city, positive predictive value and negative predictive value. Test performance in the training set was 75%, 95%, 92% and 82%, respectively. Performance in 32 validation set samples was 73%, 81%, 67% and 85%, respectively. Monocyte antigen presentation correlated signifi cantly (Spearman r=0.423, p=0.022) with allospecifi c CD154+TcM in 29 of 32 validation samples. Conclusion: Enhanced donor alloantigen presentation by recipient monocytes predicts or associates with ACR with clinically relevant performance in training-set-validation-set testing of pediatric liver or intestine transplant recipients. This test system may have clinical utility in recipients treated with Tand B-cell ablative immunosuppressive regimens. DISCLOSURES: Ashokkumar, C.: Other, Plexision, Consultant. Sindhi, R.: Other, Plexision, Unpaid Consultlant. A9 Monocyte Presentation of Donor Antigen Predicts Acute Cellular Rejection (ACR) After Liver or Intestine Transplantation (ITx, LTx). C. Ashokkumar, M. Ningappa, B. Higgs, Q. Sun, R. Sindhi. Surgery, Children’s Hospital of Pittsburgh of UPMC, Pittsburgh, PA. Background: Enhanced donor alloantigen presentation by CD14+monocytes predicts or associates with ACR in small cohorts of pediatric LTx and ITx. Purpose: To evaluate the performance of monocyte alloantigen presentation for predicting biopsy-proven ACR in training-set-validation-set testing of 67 pediatric LTx and ITx. Methods: The frequency of recipient CD14+monocytes which presented donor and HLA-non-identical third-party alloantigen was measured with fl ow cytometry and expressed as a ratio termed the monocyte antigen presenting index (mAPI). An mAPI >1 implied increased donor antigen presentation relative to presentation of third-party alloantigen. A threshold mAPI associated with ACR was developed in 35 cross-sectional training set samples from children with ITx (n=11) and LTx (n=24) using logistic regression and applied to 32 samples from 26 independent LTx and 6 independent ITx recipients. Test results were also correlated with allospecifi c CD154+T-cytotoxic memory cells (CD154+TcM), which predict ACR with high sensitivity and specifi city. Results: Mean age was 5.9 years (range 0.6 to 21, n=67). Distribution of male: female gender was 38: 29, caucasian: other race was 58: 9, LTx: ITx was 50: 17, and rejector: non-rejector status was 31: 19 for LTx and 9: 8 for ITx recipients. Rejectors were sampled at a mean interval of 5.4 days (range 0 to 38) before biopsy-proven ACR. A signifi cantly greater mAPI was seen among rejectors compared with non-rejectors 0.6±0.7 vs 4.4±6.2, p=0.003. For predicting ACR, the performance of an mAPI ≥ 1.2, developed in 35 training set samples was measured as sensitivity, specifi city, positive predictive value and negative predictive value. Test performance in the training set was 75%, 95%, 92% and 82%, respectively. Performance in 32 validation set samples was 73%, 81%, 67% and 85%, respectively. Monocyte antigen presentation correlated signifi cantly (Spearman r=0.423, p=0.022) with allospecifi c CD154+TcM in 29 of 32 validation samples. Conclusion: Enhanced donor alloantigen presentation by recipient monocytes predicts or associates with ACR with clinically relevant performance in training-set-validation-set testing of pediatric liver or intestine transplant recipients. This test system may have clinical utility in recipients treated with Tand B-cell ablative immunosuppressive regimens. DISCLOSURES: Ashokkumar, C.: Other, Plexision, Consultant. Sindhi, R.: Other, Plexision, Unpaid Consultlant. Abstract# A10 Lymphocytes Can Play The Trojan-Horse Role in Polyoma BKV Infection. D. Morsy, L. Tibbles. Internal Medicine, University of Calgary, Calgary, AB, Canada. A10 Lymphocytes Can Play The Trojan-Horse Role in Polyoma BKV Infection. D. Morsy, L. Tibbles. Internal Medicine, University of Calgary, Calgary, AB, Canada. BKV nephropathy (BKN) is currently the leading cause of early renal allograft loss. The process starts after immune suppression following renal transplantation, which causes BK virus (BKV) reactivation, resulting in lytic injury of renal tubular epithelial cells followed by tubular infl ammation, and allograft destruction. Although the role played by lymphocytes in BKN pathogenesis remains largely uncharacterized, both cellular and humoral immunity were demonstrated to be involved in BKV early elimination. Our laboratory is interested in characterizing the role played by lymphocytes in BKV pathogenesis. Using real-time polymerase chain reaction (rtPCR) and immunoblotting, we demonstrated that BKV can infect human B and T cell lines. BKV was also shown to infect and replicate in primary lymphocytes from peripheral blood at higher effi ciency than cell lines. Viral replication was associated with remarkable changes in cell shape and behaviour, with cells acquiring a refractile, fusiform appearance and becoming more adhesive. B lymphocytes infected with BKV differentiated into both memory and plasma cells, but a signifi cant proportion of these differentiated cells were not specifi c for BKV proteins. These observations may provide a clue into the accumulation of plasma cells in renal transplants affected by BK nephropathy. The potential transmission of BKV virions between immune lymphocytes was confi rmed by rt-PCR of CFSE-labelled BKV infected and non-infected purifi ed lymphocytes that were p