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Porcine islet xenografts have the potential to provide an inexhaustible source of islets for β cell replacement. Proof‐of‐concept has been established in nonhuman primates. However, significant barriers to xenoislet transplantation remain, including the poorly understood instant blood‐mediated inflammatory reaction and a thorough understanding of early xeno‐specific immune responses. A paucity of data exist comparing xeno‐specific immune responses with alloislet (AI) responses in primates. We recently developed a dual islet transplant model, which enables direct histologic comparison of early engraftment immunobiology. In this study, we investigate early immune responses to neonatal porcine islet (NPI) xenografts compared with rhesus islet allografts at 1 hour, 24 hours, and 7 days. Within the first 24 hours after intraportal infusion, we identified greater apoptosis (caspase 3 activity and TUNEL[terminal deoxynucleotidyl transferase dUTP nick end labeling])‐positive cells) of NPIs compared with AIs. Macrophage infiltration was significantly greater at 24 hours compared with 1 hour in both NPI(wild‐type) and AIs. At 7 days, IgM and macrophages were highly specific for NPIs (α1,3‐galactosyltransferase knockout) compared with AIs. These findings demonstrate an augmented macrophage and antibody response toward xenografts compared with allografts. These data may inform future immune or genetic manipulations required to improve xenoislet engraftment. A nonhuman primate dual transplant model of islet transplantation compares allogeneic islets to porcine xenogeneic islets and demonstrates an augmented macrophage and antibody response toward xenografts and an early increase in xenograft cell death.

La infección osteoarticular en el niño es frecuente por debajo de los 10 años. El tratamiento consiste en la administración de antibióticos y en algunos casos tratamiento quirúrgico. El tiempo de antibioterapia varía, desde 2 semanas para las artritis, hasta 6 semanas en casos de osteomielitis más abigarradas. Algunos de estos medicamentos poseen complicaciones individuales directas con baja repercusión clínica.

Islet xenotransplantation is a potential treatment for diabetes without the limitations of tissue availability. Although successful experimentally, early islet loss remains substantial and attributed to an instant blood-mediated inflammatory reaction (IBMIR). This syndrome of islet destruction has been incompletely defined and characterization in pig-to-primate models has been hampered by logistical and statistical limitations of large animal studies. To further investigate IBMIR, we developed a novel in vivodual islet transplant model to precisely characterize IBMIR as proof-of-concept that this model can serve to properly control experiments comparing modified xenoislet preparations. WT and α1,3-galactosyltransferase knockout (GTKO) neonatal porcine islets were studied in nonimmunosuppressed rhesus macaques. Inert polyethylene microspheres served as a control for the effects of portal embolization. Digital analysis of immunohistochemistry targeting IBMIR mediators was performed at 1 and 24 h after intraportal islet infusion. Early findings observed in transplanted islets include complement and antibody deposition, and infiltration by neutrophils, macrophages and platelets. Insulin, complement, antibody, neutrophils, macrophages and platelets were similar between GTKO and WT islets, with increasing macrophage infiltration at 24 h in both phenotypes. This model provides an objective and internally controlled study of distinct islet preparations and documents the temporal histology of IBMIR.

We consider the problem of robustness in hierarchical Bayes models. Let X = (X1,X2, … ,Xp)τ be a random vector, the X1 being independently distributed as N(θ1,σ2) random variables (σ2 known), while the θ1 are thought to be exchangeable, modelled as i.i.d, N(μ,τ2). The hyperparameter µ is given a noninformative prior distribution π(μ) = 1 and τ2 is assumed to be independent of µ having a distribution g(τ2) lying in a certain class of distributions g. For several g's, including e-contaminations classes and density ratio classes we determine the range of the posterior mean of θ1 as g ranges over g.

Coupling shop floor software system (SFS) with the set of production equipment (SPE) becomes a complex task. It involves open and proprietary standards, information and communication technologies among other tools and techniques. Due to market turbulence, either custom solutions or standards based solutions eventually require a considerable effort of adaptation. Loose coupling concept has been identified in the organizational design community as a compensator for organization survival. Its presence reduces organization reaction to environment changes. In this paper the results obtained by the organizational design community are identified, translated and organized to support the SFS-SPE integration problem solution. A classical loose coupling model developed by organizational studies community is abstracted and translated to the area of interest. Key aspects are identified to be used as promoters of SFS-SPE loose coupling and presented in a form of a reference scheme. Furthermore, this reference scheme is proposed here as a basis for the design and implementation of a generic coupling solution or coupling framework, that is included as a loose coupling stage between SFS and SPE. A validation example with various sets of manufacturing equipment, using different physical communication media, controller commands, programming languages and wire protocols is presented, showing an acceptable level of autonomy gained by the SFS.

ABSTRACTA set of 104 isolates from human clinical samples from the United States, morphologically compatible with Bipolaris, were morphologically and molecularly identified through the sequence analysis of the internal transcribed space (ITS) region of the nuclear ribosomal DNA (rDNA). The predominant species was Bipolaris spicifera(67.3%), followed by B. hawaiiensis(18.2%), B. cynodontis(8.6%), B. micropus(2.9%), B. australiensis(2%), and B. setariae(1%). Bipolaris cynodontis, B. micropus, and B. setariaerepresent new records from clinical samples. The most common anatomical sites where isolates were recovered were the nasal region (30.7%), skin (19.2%), lungs (14.4%), and eyes (12.5%). The antifungal susceptibilities of 5 species of Bipolaristo 9 drugs are provided. With the exception of fluconazole and flucytosine, the antifungals tested showed good activity.

Immunosuppressive therapies that block the CD40/CD154 costimulatory pathway have proven to be uniquely effective in preclinical xenotransplant models. Given the challenges facing clinical translation of CD40/CD154 pathway blockade, we examined the efficacy and tolerability of CD40/CD154 pathway‐sparing immunomodulatory strategies in a pig‐to‐nonhuman primate islet xenotransplant model. Rhesus macaques were rendered diabetic with streptozocin and given an intraportal infusion of ∼50 000 islet equivalents/kg wild‐type neonatal porcine islets. Base immunosuppression for all recipients included maintenance therapy with belatacept and mycophenolate mofetil plus induction with basiliximab and LFA‐1 blockade. Cohort 1 recipients (n = 3) were treated with the base regimen alone; cohort 2 recipients (n = 5) were additionally treated with tacrolimus induction and cohort 3 recipients (n = 5) were treated with alefacept in place of basiliximab, and more intense LFA‐1 blockade. Three of five recipients in both cohorts 2 and 3 achieved sustained insulin‐independent normoglycemia (median rejection‐free survivals 60 and 111 days, respectively), compared to zero of three recipients in cohort 1. These data show that CD40/CD154 pathway‐sparing regimens can promote xenoislet survival. Further optimization of these strategies is warranted to aid the clinical translation of islet xenotransplantation.

Islet transplantation to treat type 1 diabetes has been limited in part by toxicities of current immunosuppression and recipient humoral sensitization. Blockade of the CD28/CD80/86 and CD40/CD154 pathways has shown promise to remedy both these limitations, but translation has been hampered by difficulties in translating CD154‐directed therapies. Prior CD40‐directed regimens have led to prolonged islet survival, but fail to prevent humoral allosensitization. We therefore evaluated the addition of CTLA4Ig to a CD40 blockade‐based regimen in nonhuman primate (NHP) alloislet transplantation. Diabetic rhesus macaques were transplanted allogeneic islets using the CD40‐specific antibody 3A8, basiliximab induction, and sirolimus with or without CTLA4Ig maintenance therapy. Allograft survival was determined by fasting blood glucose levels and flow cytometric techniques were used to test for donor‐specific antibody (DSA) formation. CTLA4Ig plus 3A8, basiliximab and sirolimus was well tolerated and induced long‐term islet allograft survival. The addition of CTLA4Ig prevented DSA formation, but did not facilitate withdrawal of the 3A8‐based regimen. Thus, CTLA4Ig combines with a CD40‐specific regimen to prevent DSA formation in NHPs, and offers a potentially translatable calcineurin inhibitor‐free protocol inclusive of a single investigational agent for use in clinical islet transplantation without relying upon CD154 blockade.

Costimulation blockade of the CD40/CD154 pathway has been effective at preventing allograft rejection in numerous transplantation models. This strategy has largely depended on mAbs directed against CD154, limiting the potential for translation due to its association with thromboembolic events. Though targeting CD40 as an alternative to CD154 has been successful at preventing allograft rejection in preclinical models, there have been no reports on the effects of CD40‐specific agents in human transplant recipients. This delay in clinical translation may in part be explained by the presence of cellular depletion with many CD40‐specific mAbs. As such, the optimal biologic properties of CD40‐directed immunotherapy remain to be determined. In this report, we have characterized 3A8, a human CD40‐specific mAb and evaluated its efficacy in a rhesus macaque model of islet cell transplantation. Despite partially agonistic properties and the inability to block CD40 binding of soluble CD154 (sCD154) in vitro, 3A8‐based therapy markedly prolonged islet allograft survival without depleting B cells. Our results indicate that the allograft‐protective effects of CD40‐directed costimulation blockade do not require sCD154 blockade, complete antagonism or cellular depletion, and serve to support and guide the continued development of CD40‐specific agents for clinical translation.

Significant deficiencies in understanding of xenospecific immunity have impeded the success of preclinical trials in xenoislet transplantation. Although galactose‐α1,3‐galactose, the gal epitope, has emerged as the principal target of rejection in pig‐to‐primate models of solid organ transplant, the importance of gal‐specific immunity in islet xenotransplant models has yet to be clearly demonstrated. Here, we directly compare the immunogenicity, survival and function of neonatal porcine islets (NPIs) from gal‐expressing wild‐type (WT) or gal‐deficient galactosyl transferase knockout (GTKO) donors. Paired diabetic rhesus macaques were transplanted with either WT (n = 5) or GTKO (n = 5) NPIs. Recipient blood glucose, transaminase and serum xenoantibody levels were used to monitor response to transplant. Four of five GTKO versus one of five WT recipients achieved insulin‐independent normoglycemia; transplantation of WT islets resulted in significantly greater transaminitis. The WT NPIs were more susceptible to antibody and complement binding and destruction in vitro. Our results confirm that gal is an important variable in xenoislet transplantation. The GTKO NPI recipients have improved rates of normoglycemia, likely due to decreased susceptibility of xenografts to innate immunity mediated by complement and preformed xenoantibody. Therefore, the use of GTKO donors is an important step toward improved consistency and interpretability of results in future xenoislet studies.

The widespread clinical implementation of alloislet transplantation as therapy for type 1 diabetes has been hindered by the lack of suitable islet donors. Pig‐to‐human islet xenotransplantation is one strategy with potential to alleviate this shortage. Long‐term survival of porcine islets has been achieved using CD154‐specific antibodies to interrupt the CD40/CD154 costimulation pathway; however, CD154‐specific antibodies seem unlikely candidates for clinical translation. An alternative strategy for CD40/CD154 pathway interruption is use of CD40‐specific antibodies. Herein, we evaluate the ability of a chimeric CD40‐specific monoclonal antibody (Chi220) to protect islet xenografts. Neonatal porcine islets (∼50 000 IEQ/kg) were transplanted intraportally into pancreatectomized diabetic macaques. Immunosuppression consisted of induction therapy with Chi220 and the IL‐2 receptor‐specific antibody basiliximab, and maintenance therapy with sirolimus and the B7‐specific fusion protein belatacept. Chi220 effectively promoted xenoislet engraftment and survival, with five of six treated recipients achieving insulin‐independent normoglycemia (median rejection‐free survival 59 days; mean 90.8 days, maximum 203 days). No thromboembolic phenomena were observed. CD40 represents a promising alternative to CD154 as a therapeutic target, and the efficacy of CD40‐specific antibodies in islet xenotransplantation warrants further investigation.

ABSTRACTSeveral members of the fungal genera Phialemoniumand Lecythophoraare occasional agents of severe human and animal infections. These species are difficult to identify, and relatively little is known about their frequency in the clinical setting. The objective of this study was to characterize morphologically and molecularly, on the basis of the analysis of large-subunit ribosomal DNA sequences, a set of 68 clinical isolates presumed to belong to these genera. A total of 59 isolates were determined to be Phialemoniumspecies (n= 32) or a related Cephalothecaspecies (n= 6) or Lecythophoraspecies (n= 20) or a related Coniochaetaspecies (n= 1). Nine isolates identified to be Acremoniumspp. or Phaeoacremoniumspp. were excluded from further study. The most common species were Phialemonium obovatumand Phialemonium curvatum, followed by Lecythophora hoffmannii, Cephalotheca foveolata, and Lecythophora mutabilis.

ABSTRACTSome species in the polyphyletic fungal genus Acremoniumare important opportunist pathogens. Determining the actual spectrum of species and their incidence in the clinical setting, however, has long been hampered because of the difficulties encountered in phenotypic species-level identification. The goal of this study was to re-identify a large number of clinical isolates morphologically and to confirm the identifications by comparing sequences of the internal transcribed spacer region of the rRNA gene of these isolates to those of type or reference strains of well-known Acremoniumspecies. Of the 119 isolates referred to a United States reference laboratory under the name Acremonium, only 75 were identified morphologically as belonging to that genus. The remainder (44 isolates) were identified as belonging to other morphologically similar genera. The Acremoniumclinical isolates were related to species of Hypocreales, Sordariales, and of an incertae sedisfamily of ascomycetes, Plectosphaerellaceae. A total of 50 of the 75 Acremoniumisolates (67%) could be identified by molecular means, the prevalent species being Acremonium kiliense(15 isolates), A. sclerotigenum-A. egyptiacum(11 isolates), A. implicatum(7 isolates), A. persicinum(7 isolates), and A. atrogriseum(4 isolates). One of the most interesting findings of our study was that we identified several species among this large collection of clinical isolates that had not previously been reported from human infections, and we failed to confirm other Acremoniumspecies, such as A. potronii, A. recifei, and A. strictum, that had been considered significant. The most common anatomic sites for Acremoniumisolates were the respiratory tract (41.3%), nails (10.7%), and the eye (9.3%). Antifungal susceptibility testing demonstrated high MICs for all agents tested, except for terbinafine. Since numerous isolates could not be identified, we concluded that the list of opportunistic Acremoniumspecies is far from be complete and that a considerable number of additional species will be discovered.