Analysis of swine leukocyte antigen class I gene profiles and porcine endogenous retrovirus viremia level in a transgenic porcine herd inbred for xenotransplantation research

Molecular characterization of swine leukocyte antigen (SLA) genes is important for elucidating the immune responses between swine-donor and human-recipient in xenotransplantation. Examination of associations between alleles of SLA class I genes, type of pig genetic modification, porcine endogenous retrovirus (PERV) viral titer, and PERV subtypes may shed light on the nature of xenograft acceptance or rejection and the safety of xenotransplantation. No significant difference in PERV gag RNA level between transgenic and non-transgenic pigs was noted; likewise, the type of applied transgene had no impact on PERV viremia. SLA-1 gene profile type may correspond with PERV level in blood and thereby influence infectiveness. Screening of pigs should provide selection of animals with low PERV expression and exclusion of specimens with PERV-C in the genome due to possible recombination between A and C subtypes, which may lead to autoinfection. Presence of PERV-C integrated in the genome was detected in 31.25% of specimens, but statistically significant increased viremia in specimens with PERV-C was not observed. There is a need for multidirectional molecular characterization (SLA typing, viremia estimation, and PERV subtype screening) of animals intended for xenotransplantation research in the interest of xeno-recipient safety.

Non-invasive Myocardial Strain Imaging to Evaluate Graft Failure in Cardiac Xenotransplantation / 대한이식학회지

BACKGROUND: The shortage of human hearts for allotransplantation makes xenotransplantation a possible option for controllable organ providers. To detect acute xenograft rejection, invasive biopsy seems inevitable; however, this occasionally results in poor incision wound healing or infection. To date, no method of noninvasive imaging for early detection of xenograft rejection has been established. We hypothesized that ultrasound speckle tracking would better detect xenograft failure than routine left ventricular ejection fractions (EF). METHODS: From August 2013 to July 2015, a total of six cardiac heterotopic xenotransplants (α 1, 3-galactosyltransferase gene-knockout porcine heart) into cynomolgus monkeys were monitored with echocardiography every 3 to 7 days. M-mode and two-dimensional (2D)-EF measurements and myocardial strain analyses were performed. Cardiac xenograft pathology was reviewed from the immediate postoperative biopsy, as well as the necropsy. RESULTS: Myocardial speckle tracking analysis was feasible in all six cases. The longest survival was 43 days. Only one pathology-proven immunologic rejection occurred. Cardiac xenograft failure appeared as two types: a dilated pattern with decreased EF or a myocardial-thickening pattern with preserved EF. Both antibody-mediated rejection (n=1) and sepsis-induced myocardial dysfunction (n=2) revealed decreased radial or circumferential strains, but normal-range EF. Xenograft functional decline was significant with respect to radial or circumferential strain (P=0.028), but not to conventional M-mode or 2D-EFs (P=0.600, P=0.340, respectively). CONCLUSIONS: Radial and circumferential strains were significantly decreased in both types of xenograft failure, regardless of EF. Further studies are warranted to correlate the strain analysis and immunopathological details.

Outcomes of allogeneic stem cell transplantation among patients with acute myeloid leukemia presenting active disease: Experience of a single European Comprehensive Cancer Center / Resultados do transplante alogênico de células-tronco em doentes com leucemia mieloide aguda com doença ativa: experiência de um único Centro Oncológico Europeu

Summary Introduction: Allogeneic hematopoietic stem cell transplantation (ASCT) representes a potentially curative approach for patients with relapsed or refractory acute myeloid leukemia (AML). We report the outcome of relapsed/refractory AML patients treated with ASCT. Method: A retrospective cohort from 1994 to 2013 that included 61 patients with diagnosis of relapsed/refractory AML. Outcomes of interest were transplant-related mortality (TRM), incidence of acute and chronic graft-versus-host disease (GVHD), relapse incidence, progression-free survival (PFS) and overall survival (OS). Statistical significance was set at p<0.05. Results: The median age was 61 years (range 1 to 65). The cumulative incidence of 90 days, 1 year, and 3 years TRM were 60%, 26.7%, and 13.3%, respectively (p<0.001). The incidence of relapse was 21.7% at 1 year, 13% at 3 years, and 8.7% at 5 years. Median OS was estimated to be 8 months (95CI 3.266-12.734) and median PFS, 3 months (95CI 1.835-4.165). Conclusion: In our cohort, TRM in first years after ASCT remains considerable, but ASCT in this setting seems to be a good choice for AML patients with active disease. However, novel approaches are needed to reduce TRM and relapse in this set of patients.

Resumo Introdução: o transplante alogênico de células-tronco hematopoiéticas (TCTH-alo) representa uma abordagem potencialmente curativa para pacientes com leucemia mieloide aguda (LMA) recorrente ou refratária. Nosso trabalho apresenta o resultado de pacientes com recaída ou doença refratária tratados com TCTH-alo. Método: coorte retrospectiva incluindo 61 pacientes de 1994 a 2013 com diagnóstico de recidiva/LMA refratária. Os desfechos de interesse foram mortalidade relacionada ao transplante (MRT), incidência da doença aguda e crônica do enxerto contra hospedeiro (DECH), incidência de recaídas, sobrevida livre de progressão (PFS - progression-free survival) e sobrevida global (SG). A significância estatística foi considerada para p<0,05. Resultados: a média de idade foi de 61 anos (variação de 1 a 65). A incidência cumulativa de 90 dias, 1 ano e 3 anos de MRT foram de 60%, 26,7% e 13,3%, respectivamente (p<0,001). A incidência de recaída foi de 21,7% em 1 ano, 13% em 3 anos e 8,7% em 5 anos. A SG mediana foi estimada em 8 meses (IC 95% 3,266-12,734) e a mediana de PFS, em 3 meses (IC 95% 1,835-4,165). Conclusão: em nossa coorte, MRT no primeiro ano após o transplante permanece considerável, mas TCTH-alo nesse cenário parece ser uma boa opção para pacientes com LMA ativa. No entanto, novas abordagens são necessárias para reduzir MRT e recaída nesse conjunto de pacientes.

Tomographic evaluation of atrophic maxilla rehabilitated with autogenous and xenogeneic block grafts

Aim: The aim of this study was to evaluate the dimensional stability of autogenous and xenogenous bone blocks after grafting procedures using cone beam computed tomography Material and Methods: Autogenous (n=6) and xenogeneic (n=7) bone graft blocks were evaluated after 8 (T1) and 16 (T2) months. A dimensional analysis was carried using linear measurements of the height and thickness of the blocks in the tomographic exam. Results: For the autogenous bone blocks, there was a reduction in height of 1.42mm (10.06%) and a reduction in mean thickness of 1.24mm (29.60%). For the xenogeneic bone blocks, the mean height reduction was 1.38mm (10.02%) and the mean thickness reduction was 0.97mm (18.81%) with remodeling (26.62%). However, there were no significant differences between the xenogeneic and autogenous bone blocks (p=0.366). Conclusions: The results showed no differences in the dimensional stability of autogenous or xenogenous bone graft blocks. However, clinical and experimental studies with longer follow up periods are needed to elucidate the mechanisms involved in the remodeling process of bone grafts.

Substitutos ósseos – equino e bovino – associados ou não ao PRP em cavidades mandibulares de cães Beagle: estudo split-mouth qualitativo / Bone substitutes – equine and bovine – associated or not to PRP in Beagle dog’s mandibular cavities: split-mouth qualitative study

Objetivo: avaliar o processo de reparo ósseo usando os biomateriais GenOx e Bio-Gen, associados ou não ao PRP, comparando os osteocondutores entre si e a inserção do PRP qualitativamente. Material e métodos: foram utilizados seis cães fêmeas da raça Beagle, dois anos de idade, 10 kg. Foram confeccionados seis defeitos ósseos circulares com 6 mm de diâmetro em corpo de mandíbula, sendo três cavidades na hemimandíbula direita e três na porção esquerda. Cada cavidade em ambos os lados foi preenchida com os diferentes materiais: Bio-Gen, controle (coágulo), e GenOx isoladamente. Do lado esquerdo da mandíbula as cavidades sofreram adição de PRP. Nos intervalos de 30, 60 e 90 dias foram coletadas amostras e o material foi submetido à rotina histológica. Realizou-se análise qualitativa por meio da observação do processo de reparo com magnificação de 20x. Resultados: notou-se reparo mais evoluído no grupo Bio-Gen + PRP, quando comparado aos demais. Os grupos com a adição de PRP nos biomateriais demonstraram osso secundário aos 30, 60 e 90 dias. Conclusão: o osso equino apresentou os melhores resultados quanto à formação de osso maduro, e sua eficácia foi superior quando associado ao PRP.

to evaluate the bone repair process with GenOx and Bio-Gen biomaterials, associated or not to PRP, from the qualitative aspect. Material and Methods: six female beagle dogs (2 years-old, 10kg) were used. Six circular bone defects (6mm in diameter) were prepared, being three on the left and three on the right mandibular side. Each cavity on both sides was filled with: Bio-Gen, coagulum (control), and Gen-Ox, being one side receiving PRP. Samples were collected at 30, 60, and 90 days for histological quantitative analysis at 20x magnification. Results: the Bio-Gen+PRP group demonstrated more advanced repair when compared to the other groups. The use of PRP generated secondary bone at all time periods. Conclusion: the equine substitute bone presented the best results regarding mature bone formation, given its efficacy enhanced by PRP

Aplicabilidade dos enxertos em bloco de origem xenógena nas reconstruções ósseas: relato de caso clínico com avaliação tomográfica e histológica após seis meses / Applicability of xenogenous onlay grafts in bone reconstruction: case report with tomographic and histologic evaluation after six months

O osso autógeno é considerado padrão-ouro para reconstrução óssea em bloco e sustentação dos implantes dentários, mas limitações na disponibilidade e aumento na morbidade são associados a este material. Assim, o osso xenógeno em bloco vem sendo abordado como um substituto viável ao osso autógeno nos casos de recontorno vestibular do rebordo ósseo. Este caso clínico demonstrou a técnica de utilização deste material. Uma paciente de 52 anos de idade e com deficiência estética significativa na região anterior superior recebeu enxerto sintético em bloco fixado com parafusos apropriados. Após seis meses, quatro implantes foram instalados e permitida a osseointegração por mais seis meses. Tomografias computadorizadas foram realizadas antes (T0), após a cirurgia de enxertia do bloco (T1), e após o tempo de consolidação (T2), com as mudanças nos contornos volumétricos sendo comparadas em programa apropriado. Análises histológicas também foram realizadas ao redor do osso do parafuso removido. A estabilidade volumétrica do material foi considerada compatível com a literatura publicada após seis meses. Houve neoformação óssea ao redor do enxerto xenógeno com atividade de remodelação óssea.

Autogenous bone is considered the gold standard material for bone block reconstruction and dental implant supporting, but limited availability and morbidity are associated to this material. Thus, exogenous block substitutes have been studied for such bone augmentation. This case report describes the potential application of this material. A 52 years-old patient with significant deficit at the anterior region received a synthetic block secured with appropriate screws. Six months later, four dental implants were placed and osseointegration allowed for more six months. CBCT scans were performed at baseline (T0), after block grafting (T1), and after consolidation phase (T2). Volumetric changes were compared in the recommended software. Histological analyses were performed around the retrieved screws. The volumetric stability of this material after six months was considered compatible with the already published literature. Bone neoformation was seen around the xenograft with associated bone remodeling

The Role of Macrophages in Transplant Rejection / 대한이식학회지

Macrophage accumulation has been recognized as a feature of allograft rejection, however, the role of macrophages in rejection remains underappreciated. Macrophages are present within graft tissues throughout the lifespan of the graft, including acute rejection episodes. Recent advances in macrophage biology have demonstrated that different types of macrophages in grafts serve a range of functions, including promotion or attenuation of inflammation, participation in innate and adaptive immune responses, and mediation of tissue injury, fibrosis, and tissue repair. Macrophages contribute to both the innate and acquired arms of the alloimmune response, and, thus, may be involved in all aspects of acute and chronic allograft rejection. Macrophages are also involved in hyperacute and acute vascular rejection of xenografts. A deeper understanding of how macrophages accumulate within grafts and of the factors that control differentiation and function of these cells could lead to identification of novel therapeutic targets in transplantation.

Periodontal regeneration capacity of equine particulate bone in canine alveolar bone defects

PURPOSE: This study was performed to evaluate the periodontal wound healing effect of particulate equine bone mineral on canine alveolar bone defects. METHODS: Twelve adult male beagle dogs were used as study subjects. The mandibular second and fourth premolars were extracted prior to the experimental surgery, and the extraction sites were allowed to heal for 8 weeks. After periodontal probing, two-walled defects were created at the mesial and distal sides of the mandibular third premolars bilaterally, and the defects were filled with equine particulate bone with collagen membrane or bovine particulate bone with collagen membrane, or collagen membrane alone. The defects without any treatment served as negative controls. After probing depth measurement, animals were sacrificed at 10, 16, and 24 post-surgery weeks for micro-computed tomographic and histomorphometric analysis. RESULTS: The equine particulate bone-inserted group showed significantly decreased values of probing depth and first bone contact compared to the negative control and collagen membrane alone groups at weeks 10, 16, and 24 (P < 0.05). There were no significant differences in the new cementum length, newly-formed bone area, or newly-formed bone volume between equine particulate bone- and bovine particulate bone-inserted groups, both of which showed significantly increased values compared to the negative control and collagen membrane alone groups (P < 0.05). CONCLUSIONS: Equine particulate bone showed significant differences in probing depth, first bone contact, new cementum length, newly formed bone area, and bone volume fraction values when compared to the negative control and collagen membrane alone groups. There were no significant differences between equine and bovine particulate bone substitutes in these parameters; therefore, we can conclude that equine particulate bone is equivalent to bovine bone for periodontal regeneration.

Heterologous corneal endothelial cell transplantation: human corneal endothelial cell transplantation in Lewis rats

A heterologous corneal endothelial transplantation was attempted using human endothelial cells and a Lewis rat penetrating keratoplasty model. Cultured human endothelial cells were seeded to a Lewis rat cornea, which was denuded of its endothelium. When grafted into the syngeneic Lewis rat, the graft remained clear for at least five days, and then became opaque and edematous because of immune rejection reaction. In contrast, corneas denuded of their endothelium became opaque and edematous immediately after transplantation. These results demonstrate that transplanted endothelial cells have enough antigens to induce rejection reaction even though they have the functional capacity to deturge the cornea.

INHIBITORY EFFECTS OF ACTINOMYCIN 23-21 ON TRANSPLANTED TUMORS OF HUMAN NASOPHARYNGEAL CARCINOMATOUS CELLS AND GASTRIC CARCINOMATOUS CELLS IN NUDE MICE / 中国药理学通报

Actinomycin 23-21 ( ACT 23-21 ) is an anticancer antibiotic of Actinmycines. This antibiotic was produced from soil Streptomyces flaveolus which was isolated and obtained from soil samples in Fuzhou, China.The effects of ACT 23-21 were observed on using 2 transplanted models of human nasophryangeal carcinomatous cells ( CNE-2Z ) and human gastric carcinomatous cells ( MGc-803 ) in nude mice. At ACT 23-21 50?g/kg, the inhibition rate for transplanted tumors of CNE-2Z and MGc-803 were 58.4% (P

Examination of immune tolerance to heterologous-transplanted tumor of human stomach cancer in Syria Hamsters / 中国免疫学杂志

Objective: To study immune tolerance state to heterologous- transplanted tumor of human stomach cancer in Syria Hamsters. Methods: Syria hamsters within 24 hous after bom were intraperitoneally inoculated primary BCC-823 cells of human stomach cancer to establish the tumor model.Lymphocyte transformation test and complement dependent cytotoxicity test were performed. Lymphocytic infiltration from host in tumor transplanted was observed.Some neonatal Syria Hamsers were intraperitoneally inoculated dead primary cells of human stomach cancer to induce immune tolerance, and then re-inoculated subcutaneously live cells at three-week age. Tumor growth was observed and its relationship to immune inhibitory factor secreted from the tumor transplanted was studied.Results:Tumor cells from transplantation failed to induce the lymphocyte transformation of tumor-carrying Syrian hamsters and the serum from tumor-carrying Syrian hamsters couldn't cause complement dependent cytotoxicity to tumor cells of transplantation.The infiltration of of lymphocyte from host was not found in the tumor transplanted.The re-inoculation with live human stomach cancer cells in Syria hamsters at three-week age succeeded in inducing tumor after immune tolerance was induced by inoculatin dead cells. Conclusion: The Syria hamster after the inoculation of tumor cells has produced specific immune tolerance to transplanted tumor.