A Transgenic Pig Model With Human Mutant SOD1 Exhibits the Early Pathology of Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) causes progressive degeneration of the motor neurons. In this study, we delivered the genetic construct including the whole locus of human mutant superoxide dismutase 1 (SOD1) with the promoter region of human SOD1 into porcine zygotes using intracytoplasmic sperm injection-mediated gene transfer, and we thereby generated a pig model of human mutant SOD1-mediated familial ALS. The established ALS pig model exhibited an initial abnormality of motor neurons with accumulated misfolded SOD1. The ALS pig model, with a body size similar to that of human beings, will provide opportunities for cell and gene therapy platforms in preclinical translational research.

Batteryless wireless magnetostrictive Fe30Co70/Ni clad plate for human coronavirus 229E detection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been garnered increasing for its rapid worldwide spread. Each country had implemented city-wide lockdowns and immigration regulations to prevent the spread of the infection, resulting in severe economic consequences. Materials and technologies that monitor environmental conditions and wirelessly communicate such information to people are thus gaining considerable attention as a countermeasure. This study investigated the dynamic characteristics of batteryless magnetostrictive alloys for energy harvesting to detect human coronavirus 229E (HCoV-229E). Light and thin magnetostrictive Fe-Co/Ni clad plate with rectification, direct current (DC) voltage storage capacitor, and wireless information transmission circuits were developed for this purpose. The power consumption was reduced by improving the energy storage circuit, and the magnetostrictive clad plate under bending vibration stored a DC voltage of 1.9 V and wirelessly transmitted a signal to a personal computer once every 5 min and 10 s under bias magnetic fields of 0 and 10 mT, respectively. Then, on the clad plate surface, a novel CD13 biorecognition layer was immobilized using a self-assembled monolayer of -COOH groups, thus forming an amide bond with -NH2 groups for the detection of HCoV-229E. A bending vibration test demonstrated the resonance frequency changes because of HCoV-229E binding. The fluorescence signal demonstrated that HCoV-229E could be successfully detected. Thus, because HCoV-229E changed the dynamic characteristics of this plate, the CD13-modified magnetostrictive clad plate could detect HCoV-229E from the interval of wireless communication time. Therefore, a monitoring system that transmits/detects the presence of human coronavirus without batteries will be realized soon.

Generation of heterozygous PKD1 mutant pigs exhibiting early-onset renal cyst formation.

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease, manifesting as the progressive development of fluid-filled renal cysts. In approximately half of all patients with ADPKD, end-stage renal disease results in decreased renal function. In this study, we used CRISPR-Cas9 and somatic cell cloning to produce pigs with the unique mutation c.152_153insG (PKD1insG/+). Pathological analysis of founder cloned animals and progeny revealed that PKD1insG/+ pigs developed many pathological conditions similar to those of patients with heterozygous mutations in PKD1. Pathological similarities included the formation of macroscopic renal cysts at the neonatal stage, number and cystogenic dynamics of the renal cysts formed, interstitial fibrosis of the renal tissue, and presence of a premature asymptomatic stage. Our findings demonstrate that PKD1insG/+ pigs recapitulate the characteristic symptoms of ADPKD.

Moving towards a novel therapeutic strategy for hyperammonemia that targets glutamine metabolism.

Patients with urea cycle disorders intermittently develop episodes of decompensation with hyperammonemia. Although such an episode is often associated with starvation and catabolism, its molecular basis is not fully understood. First, we attempted to elucidate the mechanism of such starvation-associated hyperammonemia. Using a mouse embryonic fibroblast (MEF) culture system, we found that glucose starvation increases ammonia production, and that this increase is associated with enhanced glutaminolysis. These results led us to focus on α-ketoglutarate (AKG), a glutamate dehydrogenase inhibitor, and a major anaplerotic metabolite. Hence, we sought to determine the effect of dimethyl α-ketoglutarate (DKG), a cell-permeable AKG analog, on MEFs and found that DKG mitigates ammonia production primarily by reducing flux through glutamate dehydrogenase. We also verified that DKG reduces ammonia in an NH4 Cl-challenged hyperammonemia mouse model and observed that DKG administration reduces plasma ammonia concentration to 22.8% of the mean value for control mice that received only NH4 Cl. In addition, we detected increases in ornithine concentration and in the ratio of ornithine to arginine following DKG treatment. We subsequently administered DKG intravenously to a newborn pig with hyperammonemia due to ornithine transcarbamylase deficiency and found that blood ammonia concentration declined significantly over time. We determined that this effect is associated with facilitated reductive amination and glutamine synthesis. Our present data indicate that energy starvation triggers hyperammonemia through enhanced glutaminolysis and that DKG reduces ammonia accumulation via pleiotropic mechanisms both in vitro and in vivo. Thus, cell-permeable forms of AKG are feasible candidates for a novel hyperammonemia treatment.

Asymmetric Transfer Hydrogenative Amination of Benzylic Ketones Catalyzed by Cp*Ir(III) Complexes Bearing a Chiral N-(2-Picolyl)sulfonamidato Ligand.

A convenient asymmetric reductive amination of benzylic ketones (α-arylated ketones) catalyzed by newly designed Cp*Ir complexes bearing a chiral N-(2-picolyl)sulfonamidato ligand was developed. Using readily available ß-amino alcohols as chiral aminating agents, a range of benzo-fused and acyclic ketones were successfully reduced with formic acid in methanol at 40 °C to afford amines with favorable chemo- and diastereoselectivities. The amino alcohol-derived chiral auxiliary was easily removed by mild periodic oxidants, leading to optically active primary ß-arylamines without erosion of the optical purity (up to 97% ee). The excellent catalytic performance was retained even upon lowering the amount of catalyst to a substrate/catalyst (S/C) ratio of 20,000, and the amination could be performed on a large scale exceeding 100 g. The precise hydride transfer to iminium species generated from the ketonic substrate and the chiral amine counterpart was suggested by the mechanistic studies on stoichiometric reactions of isolable hydridoiridium complexes and model intermediates such as N,O-acetal, enamine, and iminium compounds.

Subjective and Objective Outcomes of Surgery for Rheumatoid Forefoot Deformities Under the Current Treatment Paradigm.

We investigated the clinical outcomes of surgical procedures for the treatment of forefoot deformities in patients with rheumatoid arthritis. Twenty feet in 16 women (mean age 62.1 years) underwent corrective osteotomy of the first metatarsal bone with shortening oblique osteotomy of the lesser metatarsophalangeal joints (joint-preservation group), while 13 feet in 12 women (mean age 67.4 years) underwent arthrodesis of the first metatarsophalangeal joint with resection arthroplasty of the lesser metatarsophalangeal joints (joint-sacrifice group); mean follow-up for each group was 25.8 and 23.8 months, respectively. The mean total Japanese Society for Surgery of the Foot (JSSF) scale improved significantly from 64.2 to 89.2 in the joint-preservation group (p < .001), and from 54.2 to 74.2 in the joint-sacrifice group (p = .003). In the joint-preservation group, the postoperative range of motion (ROM) of the joint, walking ability, and activities of daily living scores of the JSSF scale were significantly higher than those in the joint-sacrifice group (p = .001, p = .001, and p = .019, respectively). There were no differences in the subscale scores of the self-administered foot evaluation questionnaire between 2 groups either pre- or postoperatively. No differences in the postoperative complications were found between 2 groups. Although the joint-sacrificing procedure resulted in lower objective outcomes than the joint-preserving procedure regarding the ROM of the joint, the walking ability, and the level of activities of daily living, both procedures resulted in similar treatment outcomes when evaluated by the subjective measures.

Modeling lethal X-linked genetic disorders in pigs with ensured fertility.

Genetically engineered pigs play an indispensable role in the study of rare monogenic diseases. Pigs harboring a gene responsible for a specific disease can be efficiently generated via somatic cell cloning. The generation of somatic cell-cloned pigs from male cells with mutation(s) in an X chromosomal gene is a reliable and straightforward method for reproducing X-linked genetic diseases (XLGDs) in pigs. However, the severe symptoms of XLGDs are often accompanied by impaired growth and reproductive disorders, which hinder the reproduction of these valuable model animals. Here, we generated unique chimeric boars composed of mutant cells harboring a lethal XLGD and normal cells. The chimeric boars exhibited the cured phenotype with fertility while carrying and transmitting the genotype of the XLGD. This unique reproduction system permits routine production of XLGD model pigs through the male-based breeding, thereby opening an avenue for translational research using disease model pigs.

Correction: Pigs with δ-sarcoglycan deficiency exhibit traits of genetic cardiomyopathy.

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Pigs with δ-sarcoglycan deficiency exhibit traits of genetic cardiomyopathy.

Genetic cardiomyopathy is a group of intractable cardiovascular disorders involving heterogeneous genetic contribution. This heterogeneity has hindered the development of life-saving therapies for this serious disease. Genetic mutations in dystrophin and its associated glycoproteins cause cardiomuscular dysfunction. Large animal models incorporating these genetic defects are crucial for developing effective medical treatments, such as tissue regeneration and gene therapy. In the present study, we knocked out the δ-sarcoglycan (δ-SG) gene (SGCD) in domestic pig by using a combination of efficient de novo gene editing and somatic cell nuclear transfer. Loss of δ-SG expression in the SGCD knockout pigs caused a concomitant reduction in the levels of α-, ß-, and γ-SG in the cardiac and skeletal sarcolemma, resulting in systolic dysfunction, myocardial tissue degeneration, and sudden death. These animals exhibited symptoms resembling human genetic cardiomyopathy and are thus promising for use in preclinical studies of next-generation therapies.

Prognostic significance of p16 expression in high-grade prostate adenocarcinoma.

Management of advanced hormone-naïve prostate cancer (HNPC) is a critical public health issue. Useful prognostic markers are thus needed to select patients who will benefit from recently introduced upfront therapies. p16 expression is an adverse prognostic marker in prostate cancer. The present study aimed to determine whether p16 expression would serve as an adverse prognostic marker in advanced HNPC. A total of 79 patients diagnosed by needle biopsy with adenocarcinoma Gleason score ≥8 between 2010 and 2013 at Aichi Medical University were included in this study. The median patient age was 73 (range 52-87) years. The median follow-up was 62 months (range 2-98). Fourteen patients had p16-positive samples. Fifteen patients died from prostate cancer, 10 of whom were in the p16-positive group. p16 positivity was associated with clinical T stage (P < 0.001), presence of IDC-P (P < 0.001), distant metastasis (P < 0.001) and lymph node metastasis (P < 0.001). These results indicate that p16 expression is associated with adverse prognostic factor of prostate cancer and suggest that p16 expression may provide useful information for treatment planning and identifying suitable candidates for upfront chemotherapy or androgen receptor axis-targeted therapy.

Clinical pharmacokinetics of flomoxef in prostate tissue and dosing considerations for prostatitis based on site-specific pharmacodynamic target attainment.

Flomoxef is used to treat bacterial prostatitis; however, its prostatic pharmacokinetics have not been fully clarified. Flomoxef (500 or 1000 mg) was administered to patients with benign prostatic hypertrophy (n = 54). After a 0.5-h infusion, venous blood samples were drawn at time points of 0.5-5 h, and prostate tissue samples were collected at time points of 0.5-1.5 h during transurethral resection of the prostate. The drug concentrations in plasma and prostate tissue were analyzed pharmacokinetically and used for a stochastic simulation to predict the probability of attaining pharmacodynamic target in prostate tissue. Showing dose linearity in the prostatic pharmacokinetics, flomoxef rapidly penetrated into prostate tissue, with a prostate/plasma ratio of 0.48-0.50 (maximum drug concentration) and 0.42-0.55 (area under the drug concentration-time curve). Against the tested populations of Escherichia coli, Klebsiella and Proteus species isolates, 0.5-h infusion of 1000 mg three times daily achieved a ≥90% expected probability of attaining the bactericidal target (70% of the time above the minimum inhibitory concentration [MIC]) in prostate tissue. The site-specific pharmacodynamic-based breakpoint (the highest MIC at which the target-attainment probability in prostate tissue was >90%) values were 0.25 mg/L (MIC for 90th percentile of E. coli and Klebsiella species) for 500 mg four times daily and 0.5 mg/L (MIC90 of Proteus species) for 1000 mg four times daily. These results help to fully characterize the prostatic pharmacokinetics of flomoxef, while also helping to rationalize and optimize the dosing regimens for prostatitis based on site-specific pharmacodynamic target attainment.

Increased infiltration of CCR4-positive regulatory T cells in prostate cancer tissue is associated with a poor prognosis.

BACKGROUND: Regulatory T cells (Tregs) play important roles in the suppression of immune responses, including antitumor immune responses. C-C chemokine receptor 4 (CCR4) is highly expressed on effector Tregs, and anti-CCR4 antibody is attracting attention as a novel immunotherapeutic agent for solid tumors. This study aimed to evaluate the expression of CCR4-positive Tregs (CCR4+Tregs) in prostate cancer and estimate the clinical potential of CCR4-targeting therapy for prostate cancer. METHODS: A total of 15 radical prostatectomy (RP) specimens and 60 biopsy specimens from individuals diagnosed with prostate cancer were analyzed to evaluate the infiltration of CCR4+Tregs in prostate cancer. The relationships between the number of CCR4+Tregs and clinical parameters were investigated in RP and biopsy specimens. Moreover, the total number of Tregs, CCR4+Tregs, and T cells and the ratio of CCR4+Tregs to Tregs and T cells in biopsy specimens were compared between patients with poor prognosis who progressed to castration-resistant prostate cancer (CRPC) within 12 months (n = 13) and those with good prognosis who were stable with hormone-sensitive prostate cancer over 12 months (n = 47). Furthermore, biopsy specimens were divided into two groups: low and high CCR4+Treg expression groups and the prognosis was compared between them. RESULTS: There was a higher expression of CCR4+Tregs in RP specimens with a higher (≥8) Gleason score than in those with a lower (<8) Gleason score (P = .041). In biopsy specimens, 65.9% Tregs were positive for CCR4. The number of CCR4+Tregs positively correlated with clinical stage (P < .001) and Gleason score (P = .006). The total number of Tregs and CCR4+Tregs significantly increased in the poor prognosis group compared with that in the good prognosis group (P = .024 and .01, respectively). Furthermore, patients with lower CCR4+Treg expression levels showed a significantly longer time to progression to CRPC (not reached vs 27.3 months; P < .001) and median survival time (not reached vs 69.0 months; P = .014) than those with higher expression levels. CONCLUSIONS: CCR4+Tregs are highly infiltrated in the prostate tissue of patients with poor prognosis with potential to progress to CRPC. Furthermore, the degree of infiltration of CCR4+Tregs is related to the prognosis of prostate cancer.

Reductive Amination of Ketonic Compounds Catalyzed by Cp*Ir(III) Complexes Bearing a Picolinamidato Ligand.

Cp*Ir complexes bearing a 2-picolinamide moiety serve as effective catalysts for the direct reductive amination of ketonic compounds to give primary amines under transfer hydrogenation conditions using ammonium formate as both the nitrogen and hydrogen source. The clean and operationally simple transformation proceeds with a substrate to catalyst molar ratio (S/C) of up to 20,000 at relatively low temperature and exhibits excellent chemoselectivity toward primary amines.

The phenotype of a pig with monosomy X resembling Turner syndrome symptoms: a case report.

The partial or complete loss of one X chromosome in humans causes Turner syndrome (TS), which is accompanied by a range of physical and reproductive pathologies. This article reports similarities between the phenotype of a pig with monosomy X and the symptoms of TS in humans. Born as the offspring of a male pig carrying a mutation in an X-chromosomal gene, ornithine transcarbamylase (OTC), the female pig (37,XO) was raised to the age of 36 months. This X-monosomic pig presented with abnormal physical characteristics including short stature, micrognathia, and skeletal abnormalities in the limbs. Furthermore, the female did not exhibit an estrous cycle, even after reaching the age of sexual maturity, and showed no ovarian endocrine activity except for an irregular increase in blood 17ß-estradiol levels, which was seemingly attributable to sporadic follicular development. An autopsy at 36 months revealed an undeveloped reproductive tract with ovaries that lacked follicles. These data demonstrated that the growth processes and anatomical and physiological characteristics of an X-monosomic pig closely resembled those of a human with TS.

GABAB receptor regulates proliferation in the high-grade chondrosarcoma cell line OUMS-27 via apoptotic pathways.

BACKGROUND: High-grade chondrosarcoma, which has a high incidence of local recurrence and pulmonary metastasis despite surgical resection, is associated with poor prognosis. Therefore, new and effective adjuvant therapies are urgently required for this disease. Gamma-aminobutyric acid (GABA), which acts as a neurotrophic factor during nervous system development, is related to the proliferation and migration of certain cancer cells. The GABAergic system, which is composed of GABA, the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD), and GABA receptors, has an important function in nerve growth and development of neural crest. Therefore, the GABAergic system may play important functional roles in the proliferation of chondrosarcoma cells, which are derived from neural crest cells. We examined the anti-tumor effects of the GABAergic system on a chondrosarcoma cell line. METHODS: We evaluated the underlying mechanisms of the anti-tumor effects of the GABAergic system, such as the involvement of different signaling pathways, apoptosis, and cell cycle arrest, in the high-grade chondrosarcoma cell line OUMS-27. In addition, we performed whole-cell patch-clamp recordings for Ca2+ currents and evaluated the changes in intracellular Ca2+ concentration via Ca2+ channels, which are related to the GABAB receptor in high-grade chondrosarcoma cells. RESULTS: The GABAB receptor antagonist CGP had anti-tumor effects on high-grade chondrosarcoma cells in a dose-dependent manner. The activities of caspase 3 and caspase 9 were significantly elevated in CGP-treated cells compared to in untreated cells. The activity of caspase 8 did not differ significantly between untreated cells and CGP-treated cells. However, caspase 8 tended to be up-regulated in CGP-treated cells. The GABAB receptor antagonist exhibited anti-tumor effects at the G1/S cell cycle checkpoint and induced apoptosis via dual inhibition of the PI3/Akt/mTOR and MAPK signaling pathways. Furthermore, the changes in intracellular Ca2+ via GABAB receptor-related Ca2+ channels inhibited the proliferation of high-grade chondrosarcoma cells by inducing and modulating apoptotic pathways. CONCLUSIONS: The GABAB receptor antagonist may improve the prognosis of high-grade chondrosarcoma by exerting anti-tumor effects via different signaling pathways, apoptosis, cell cycle arrest, and Ca2+ channels in high-grade chondrosarcoma cells.

Effectiveness of bioengineered islet cell sheets for the treatment of diabetes mellitus.

BACKGROUND: The present study aimed to evaluate whether bioengineered mouse islet cell sheets can be used for the treatment of diabetes mellitus. METHODS: Isolated mouse pancreatic islets were dispersed, and cells were plated on temperature-responsive culture plates coated with iMatrix-551. On day 3 of culture, the sheets were detached from the plates and used for further analysis or transplantation. The following parameters were assessed: (1) morphology, (2) expression of ß-cell-specific transcription factors and other islet-related proteins, (3) methylation level of the pancreatic duodenal homeobox-1 (Pdx-1) promoter, as determined by bisulfite sequencing, and (4) levels of serum glucose after transplantation of one or two islet cell sheets into the abdominal cavity of streptozotocin-induced diabetic severe combined immunodeficiency mice. RESULTS: From each mouse, we recovered approximately 233.3 ± 12.5 islets and 1.4 ± 0.1 × 105 cells after dispersion. We estimate that approximately 68.2% of the cells were lost during dispersion. The viability of recovered single cells was 91.3 ± 0.9%. The engineered islet cell sheets were stable, but the messenger RNA levels of various ß-cell-specific transcription factors were significantly lower than those of primary islets, whereas Pdx-1 promoter methylation and the expression of NeuroD, Pdx-1, and glucagon proteins were similar between sheets and islets. Moreover, transplantation of islet cell sheets did not revert serum hyperglycemia in any of the recipient mice. CONCLUSIONS: Engineering effective islet cell sheets require further research efforts, as the currently produced sheets remain functionally inferior compared with primary islets.

Impact of a novel biopsy instrument with a 25-mm side-notch needle on the detection of prostate cancer in transrectal biopsy.

OBJECTIVES: To evaluate the impact of a novel biopsy instrument that extends the length of the side-notch on the detection of prostate cancer in transrectal needle biopsy. METHODS: We collaborated with a biopsy needle manufacturer and developed a novel biopsy instrument (PRIMECUT II long-notch type) with a 25-mm side-notch length and 28-mm stroke length to take longer tissue cores. The sampled core length, cancer detection rate, pain and complications of 489 patients who underwent transrectal biopsy using the long-notch needle were compared with those of 469 patients who underwent biopsy using a normal instrument with a 19-mm side-notch length and 22-mm stroke length. RESULTS: The mean length of tissue taken by the long-notch needle was significantly longer than that of tissue taken by the normal-notch needle (16.3 vs 22.4 mm, P < 0.001). The overall cancer detection rate was 42.0% for the normal-notch needle and 51.1% for the long-notch needle (P = 0.005). In patients with a prostate volume of 20-40 mL, the cancer detection rate for the long-notch needle was especially higher than that for the normal-notch needle (74.2% vs 47.5%, P < 0.001). Multivariate analysis showed that the long-notch needle improved cancer detection significantly (odds ratio 1.702, P < 0.001). There were no differences of pain during biopsy and complication between the two groups. CONCLUSIONS: The novel biopsy instrument with a 25-mm side-notch can take longer tissue samples safely and has a significantly higher rate of prostate cancer detection in transrectal biopsy.

Clinical pharmacokinetics and pharmacodynamic target attainment of pazufloxacin in prostate tissue: Dosing considerations for prostatitis.

The present study examined the clinical pharmacokinetics of pazufloxacin in prostate tissue and estimated the probability of target attainment for tissue-specific pharmacodynamic goals related to treating prostatitis using various intravenous dosing regimens. Patients with prostatic hypertrophy received prophylactic infusions of pazufloxacin (500 mg, n = 23; 1000 mg, n = 25) for 0.5 h prior to transurethral prostate resection. Drug concentrations in plasma (0.5-5 h) and prostate tissue (0.5-1.5 h) were measured by high-performance liquid chromatography and used for subsequent noncompartmental and three-compartmental analysis. Monte Carlo simulation was performed to evaluate the probability of target attainment of a specific minimum inhibitory concentration (MIC) in prostate tissue: the proportion that achieved both area under the drug concentration over time curve (AUC)/MIC = 100 and maximum concentration (Cmax)/MIC = 8. Prostatic penetration of pazufloxacin was good with mean Cmax ratios (prostate tissue/plasma) of 0.82-0.99 and for AUC, 0.80-0.98. The probability of reaching target MIC concentrations in prostate tissue was more than 90% for dosing schedules of 0.25 mg/L for 500 mg every 24 h (500 mg daily), 0.5 mg/L for 500 mg every 12 h (1000 mg daily), 1 mg/L for 1000 mg every 24 h (1000 mg daily), and 2 mg/L for 1000 mg every 12 h (2000 mg daily). Importantly, the 2000 mg daily regimen of pazufloxacin produced a profile sufficient to have an antibacterial effect in prostate tissue against clinical isolates of Escherichia coli and Klebsiella pneumonia with MIC values less than 2 mg/L.

Efficient modification of the myostatin gene in porcine somatic cells and generation of knockout piglets.

Myostatin (MSTN) is a negative regulator of myogenesis, and disruption of its function causes increased muscle mass in various species. Here, we report the generation of MSTN-knockout (KO) pigs using genome editing technology combined with somatic-cell nuclear transfer (SCNT). Transcription activator-like effector nuclease (TALEN) with non-repeat-variable di-residue variations, called Platinum TALEN, was highly efficient in modifying genes in porcine somatic cells, which were then used for SCNT to create MSTN KO piglets. These piglets exhibited a double-muscled phenotype, possessing a higher body weight and longissimus muscle mass measuring 170% that of wild-type piglets, with double the number of muscle fibers. These results demonstrate that loss of MSTN increases muscle mass in pigs, which may help increase pork production for consumption in the future.

A transgenic-cloned pig model expressing non-fluorescent modified Plum.

Genetically modified pigs that express fluorescent proteins such as green and red fluorescent proteins have become indispensable biomedical research tools in recent years. Cell or tissue transplantation studies using fluorescent markers should be conducted, wherein the xeno-antigenicity of the fluorescent proteins does not affect engraftment or graft survival. Thus, we aimed to create a transgenic (Tg)-cloned pig that was immunologically tolerant to fluorescent protein antigens. In the present study, we generated a Tg-cloned pig harboring a derivative of Plum modified by a single amino acid substitution in the chromophore. The cells and tissues of this Tg-cloned pig expressing the modified Plum (mPlum) did not fluoresce. However, western blot and immunohistochemistry analyses clearly showed that the mPlum had the same antigenicity as Plum. Thus, we have obtained primary proof of principle for creating a cloned pig that is immunologically tolerant to fluorescent protein antigens.