Exploring the long-term performance of air purifiers in removing particulate matter and formaldehyde across different residential environments.

Household air purifiers are widely used to enhance indoor air quality. However, limited information exists regarding the factors that influence their long-term performance. This study investigates the impact of various residential environments on the long-term efficacy of air purifiers. We deployed household air purifiers in three distinct environments: oily fumes (Group A), non-oily fumes (Group C), and a mixture of oily and non-oily fumes (Groups B-I and B-II). The selected air filter consisted of melt-blown polypropylene and activated carbon, materials commonly employed in commercial applications. The results demonstrated that the control efficiency of air purifiers in non-oily fume environments surpassed that in oily fume environments. After 12 months of operation, particulate matter (PM) concentrations rose by 92.7% and 76.5% in oily and non-oily fume environments, respectively. This increase was primarily attributed to the loss of electrostatic attraction in the polypropylene material due to the organic matter in oily particulate matter. After operating for 1000 h, the clean air delivery rate (CADR) attenuation rates for particulate matter were 70.6%, 19.9%, 16.7%, and 12.5% in Groups A, B-I, B-II, and C, respectively. The CADR attenuation rates for formaldehyde were 80.6%, 48.4%, 38.9%, and 37.3% in the same groups. Additionally, we developed a real-time prediction model for the service life of air purifiers using data from online sensors. When operated for 12 h daily at varying PM concentrations, the filters had an expected service life of 29-97 days in non-oily fume environments and 66-220 days in oily fume environments.

Dedifferentiation-associated inflammatory factors of long-term expanded human hepatocytes exacerbate their elimination by macrophages during liver engraftment.

BACKGROUND AND AIMS: Hepatocyte transplantation has been demonstrated to be effective to treat liver metabolic disease and acute liver failure. Nevertheless, the shortage of donor hepatocytes restrained its application in clinics. To expand human hepatocytes at a large scale, several dedifferentiation-based protocols have been established, including proliferating human hepatocytes (ProliHH). However, the decreased transplantation efficiency of these cells after long-term expansion largely impedes their application. APPROACH AND RESULTS: We found that accompanied with dedifferentiation, long-term cultured ProliHH (lc-ProliHH) up-regulated a panel of chemokines and cytokines related to innate immunity, which were referred to as dedifferentiation-associated inflammatory factors (DAIF). DAIF elicited excessive macrophage responses, accounting for the elimination of lc-ProliHH specifically during engraftment. Two possible strategies to increase ProliHH transplantation were then characterized. Blockage of innate immune response by dexamethasone reverted the engraftment and repopulation of lc-ProliHH to a level comparable to primary hepatocytes, resulting in improved liver function and a better survival of fumarylacetoacetate hydrolase-deficient mice. Alternatively, rematuration of lc-ProliHH as organoids reduced the expression of DAIF and led to markedly improved engraftment. CONCLUSIONS: These results revealed that lc-ProliHH triggers exacerbated macrophage activation by DAIF and provided potential solutions for clinical transplantation of lc-ProliHH.

A mobile platform for characterizing on-road tailpipe emissions and toxicity of ultrafine particles under real driving Conditions.

Acute exposure to fresh traffic-related air pollutants (TRAPs) can be high for road users, including motorbike drivers, cyclists, and pedestrians. However, evaluating the toxicity of fresh traffic emissions from on-road vehicles is challenging since pollution properties can change dynamically within a short distance and time. This study demonstrated a mobile platform equipped with an On-Board Diagnostic II (OBDII) system, a tailor-made portable emission measurement system, and an electrostatic air-liquid interface exposure system with human monocytic THP-1 cells to characterize on-road tailpipe emissions under real driving conditions. High number concentrations up to 106-107 # cm-3 of ultrafine particles (UFPs) were observed for a gasoline engine at the cold-start stage and a diesel engine during particulate filter regeneration. In particular, a substantial fraction of freshly emitted UFPs within the size less than 23 nm were observed and should be cautioned. The potential toxicity of fresh TRAPs was quantified by cell viability, cytotoxicity, oxidative stress, and inflammatory biomarkers. Results show that the decreased cell viability, increased lactate dehydrogenase (LDH) activity, and high oxidative stress induced by the fresh TRAPs were potentially contributed by gaseous pollutants as well as particles, especially driving with the high idling frequency. Moreover, the dominant contributor to the toxicity is different for gasoline's and diesel's TRAPs. Characterizing on-road air pollutant toxicity as well as physicochemical properties using an innovative mobile platform can fill this knowledge gap.

Investigating the filtration performance and service life of vehicle cabin air filters in China.

To protect occupants in vehicle cabin environments from the health risks of high concentrations of particulate matter (PM), it is important to install vehicle cabin air filter (VCAF) to eliminate PM. In this study, we investigated the filtration performance of 22 VCAFs. Results showed that the minimum average filtration efficiency was 56.1 % for particles with a diameter of 0.1-0.3 µm, a pressure drop of 33.2-250 Pa at air velocity of 2.5 m/s, and the dust-holding capacity ranged from 5.8 to 19.4 g. In addition, as the filter area increased from 0.23 m2 to 0.50 m2, the filtration efficiency for particles with a diameter of 0.1-0.3 µm increased from 56.7 % to 77.5 %, the pressure drop decreased from 96.1 to 62.5 Pa, and the dust holding capacity increased 2.7 times. Furthermore, we compared the service life of VCAF from 31 major Chinese cities and found that the service life varied greatly from maximum of 1730 h for Haikou to minimum of 352 h for Shijiazhuang. Considering occupant health risks, Beijing requires that VCAFs have PM2.5 filtration efficiency at least 88.1 %, and Liaoning requires minimum of 97.5 %. Hence, choosing the appropriate VCAF based on the atmospheric environment of different cities deserves our attention.

Delivery-First Strategy Followed by Endovascular Repair to Treat Pregnant Woman With Acute Complicated Type B Aortic Dissection.

Objective: Aortic dissection, a rare but serious condition, requires timely diagnosis and treatment. Case report: A case report involving a 33-year-old female with Stanford type B aortic dissection at 32 + 3 weeks gestational age highlights the importance of being alert to the symptoms and signs of this condition, particularly in patients with hypertension or a history of connective tissue disorders. The case report suggests a delivery first strategy followed by TEVAR procedure as the preferred approach for managing aortic dissection in pregnancy. This approach can alleviate pressure on the aorta, reduce the risk of rupture, and provide time for stabilization and preparation for the TEVAR procedure. Conclusion: The case report emphasizes the criticality of recognizing and treating aortic dissection in pregnant patients promptly, given its potential life-threatening impact on both mother and fetus.

Preclinical efficacy and safety of encapsulated proliferating human hepatocyte organoids in treating liver failure.

Alginate-encapsulated hepatocyte transplantation is a promising strategy to treat liver failure. However, its clinical application was impeded by the lack of primary human hepatocytes and difficulty in controlling their quality. We previously reported proliferating human hepatocytes (ProliHHs). Here, quality-controlled ProliHHs were produced in mass and engineered as liver organoids to improve their maturity. Encapsulated ProliHHs liver organoids (eLO) were intraperitoneally transplanted to treat liver failure animals. Notably, eLO treatment increased the survival of mice with post-hepatectomy liver failure (PHLF) and ameliorated hyperammonemia and hypoglycemia by providing liver functions. Additionally, eLO treatment protected the gut from PHLF-augmented permeability and normalized the increased serum endotoxin and inflammatory response, which facilitated liver regeneration. The therapeutic effect of eLO was additionally proved in acetaminophen-induced liver failure. Furthermore, we performed assessments of toxicity and biodistribution, demonstrating that eLO had no adverse effects on animals and remained non-tumorigenic.

Pediatric immune-mediated necrotizing myopathy.

Immune-mediated necrotizing myopathy (IMNM) is a type of inflammatory myopathy. Most patients with IMNM produce anti-3-hydroxy-3-methylglutaryl coenzyme A reductase or anti-signal-recognition particle autoantibodies. IMNM is much rarer in children than in adults. We conducted this mini review focusing on pediatric IMNM to present current evidence regarding its epidemiology, clinical characteristics, diagnosis, and treatment. Our findings indicate that pediatric IMNM often causes severe muscle weakness and is refractory to corticosteroids alone. Furthermore, delayed diagnosis is common because of the clinicopathological similarity between IMNM and inherited myopathy. Raising awareness regarding pediatric IMNM may facilitate early diagnosis and effective treatment.

Hepatocyte transplantation: The progress and the challenges.

Numerous studies have shown that hepatocyte transplantation is a promising approach for liver diseases, such as liver-based metabolic diseases and acute liver failure. However, it lacks strong evidence to support the long-term therapeutic effects of hepatocyte transplantation in clinical practice. Currently, major hurdles include availability of quality-assured hepatocytes, efficient engraftment and repopulation, and effective immunosuppressive regimens. Notably, cell sources have been advanced recently by expanding primary human hepatocytes by means of dedifferentiation in vitro. Moreover, the transplantation efficiency was remarkably improved by the established preparative hepatic irradiation in combination with hepatic mitogenic stimuli regimens. Finally, immunosuppression drugs, including glucocorticoid and inhibitors for co-stimulating signals of T cell activation, were proposed to prevent innate and adaptive immune rejection of allografted hepatocytes. Despite remarkable progress, further studies are required to improve in vitro cell expansion technology, develop clinically feasible preconditioning regimens, and further optimize immunosuppression regimens or establish ex vivo gene correction-based autologous hepatocyte transplantation.

Reversal of liver failure using a bioartificial liver device implanted with clinical-grade human-induced hepatocytes.

Liver resection is the first-line treatment for primary liver cancers, providing the potential for a cure. However, concerns about post-hepatectomy liver failure (PHLF), a leading cause of death following extended liver resection, have restricted the population of eligible patients. Here, we engineered a clinical-grade bioartificial liver (BAL) device employing human-induced hepatocytes (hiHeps) manufactured under GMP conditions. In a porcine PHLF model, the hiHep-BAL treatment showed a remarkable survival benefit. On top of the supportive function, hiHep-BAL treatment restored functions, specifically ammonia detoxification, of the remnant liver and facilitated liver regeneration. Notably, an investigator-initiated study in seven patients with extended liver resection demonstrated that hiHep-BAL treatment was well tolerated and associated with improved liver function and liver regeneration, meeting the primary outcome of safety and feasibility. These encouraging results warrant further testing of hiHep-BAL for PHLF, the success of which would broaden the population of patients eligible for liver resection.

Quantification of food packaging generation and material loss from major retailers in Taipei, Taiwan.

Packaging accounts for the largest demand for global plastic consumption and around 60% is for food and beverage packaging. The amount of packaging is increasing rapidly due to the expansion of retailer industries, especially in supermarkets and convenience stores. Plastic recycling strategies for food packaging in retailer industries need to be developed, but the current consumption and recycling status is not clear. To address this knowledge gap, this study quantifies the food packaging generation from major supermarket and convenience store chains in Taipei, Taiwan. We focus on the composition, recycling habit, and the recycling status to evaluate the packaging recyclability and major pathways for material losses. Based on our field survey and analysis, the total amount of plastic packaging generation was 21846.04 tons in 2020 with 64.99% of it being recycled. We defined the recycling rates as the continued product of Recyclable Content Ratio of the packaging itself, Sorting Accuracy Ratio of consumers, and Re-granulated Ratio in the final treatment facilities. These three ratios for major food categories were also presented to identify the hotspots of material losses. Our results suggest that to promote plastic food packaging recycling, identifying the limitations in different stages and designing corresponding strategies is crucial.

Survival-Assured Liver Injury Preconditioning (SALIC) Enables Robust Expansion of Human Hepatocytes in Fah-/- Rag2-/- IL2rg-/- Rats.

Although liver-humanized animals are desirable tools for drug development and expansion of human hepatocytes in large quantities, their development is restricted to mice. In animals larger than mice, a precondition for efficient liver humanization remains preliminary because of different xeno-repopulation kinetics in livers of larger sizes. Since rats are ten times larger than mice and widely used in pharmacological studies, liver-humanized rats are more preferable. Here, Fah-/- Rag2-/- IL2rg-/- (FRG) rats are generated by CRISPR/Cas9, showing accelerated liver failure and lagged liver xeno-repopulation compared to FRG mice. A survival-assured liver injury preconditioning (SALIC) protocol, which consists of retrorsine pretreatment and cycling 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) administration by defined concentrations and time intervals, is developed to reduce the mortality of FRG rats and induce a regenerative microenvironment for xeno-repopulation. Human hepatocyte repopulation is boosted to 31 ± 4% in rat livers at 7 months after transplantation, equivalent to approximately a 1200-fold expansion. Human liver features of transcriptome and zonation are reproduced in humanized rats. Remarkably, they provide sufficient samples for the pharmacokinetic profiling of human-specific metabolites. This model is thus preferred for pharmacological studies and human hepatocyte production. SALIC may also be informative to hepatocyte transplantation in other large-sized species.

Clinical, pathological, imaging, and genetic characterization in a Taiwanese cohort with limb-girdle muscular dystrophy.

BACKGROUND: Limb-girdle muscular dystrophy (LGMD) is a genetically heterogeneous, hereditary disease characterized by limb-girdle weakness and histologically dystrophic changes. The prevalence of each subtype of LGMD varies among different ethnic populations. This study for the first time analyzed the phenotypes and genotypes in Taiwanese patients with LGMD in a referral center for neuromuscular diseases (NMDs). RESULTS: We enrolled 102 patients clinically suspected of having LGMD who underwent muscle biopsy with subsequent genetic analysis in the previous 10 years. On the basis of different pathological categories, we performed sequencing of target genes or panel for NMDs and then identified patients with type 1B, 1E, 2A, 2B, 2D, 2I, 2G, 2 N, and 2Q. The 1B patients with LMNA mutation presented with mild limb-girdle weakness but no conduction defect at the time. All 1E patients with DES mutation exhibited predominantly proximal weakness along with distal weakness. In our cohort, 2B and 2I were the most frequent forms of LGMD; several common or founder mutations were identified, including c.1097_1099delACA (p.Asn366del) in DES, homozygous c.101G > T (p.Arg34Leu) in SGCA, homozygous c.26_33dup (p.Glu12Argfs*20) in TCAP, c.545A > G (p.Tyr182Cys), and c.948delC (p.Cys317Alafs*111) in FKRP. Clinically, the prevalence of dilated cardiomyopathy in our patients with LGMD2I aged > 18 years was 100%, much higher than that in European cohorts. The only patient with LGMD2Q with PLEC mutation did not exhibit skin lesions or gastrointestinal abnormalities but had mild facial weakness. Muscle imaging of LGMD1E and 2G revealed a more uniform involvement than did other LGMD types. CONCLUSION: Our study revealed that detailed clinical manifestation together with muscle pathology and imaging remain critical in guiding further molecular analyses and are crucial for establishing genotype-phenotype correlations. We also determined the common mutations and prevalence for different subtypes of LGMD in our cohort, which could be useful when providing specific care and personalized therapy to patients with LGMD.

Treatment experience of Taiwanese patients with anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase myopathy.

Immune-mediated necrotizing myopathy (IMNM) has emerged as a new subgroup of idiopathic inflammatory myopathy in the past decade, associated with the presence of two autoantibodies against signal recognition particle and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR). We aim to analyze the clinical, pathological, and imaging phenotypes of the patients with anti-HMGCR myopathy in our cohort. Five patients with anti-HMGCR myopathy have been enrolled who were all female; three were pediatric and two were adult patients. The muscle pathology of patients met the diagnostic criteria of IMNM. On muscle magnetic resonance imaging, adductors were earliest affected while lower legs were relatively preserved with highest degree of involvement in medial head of gastrocnemius. In upper extremities, biceps brachii was the most severely involved, followed by triceps. All patients were refractory to steroid mono-therapy. For pediatric patients, all three patients eventually became responsive to steroid with either intravenous immunoglobulin or rituximab despite variable motor function recovered at present due to different intervention timing. For adult patients, one with statin exposure responded well to steroid and azathioprine use and the motor function returned to the baseline. The other adult patient finally got stabilized and slowly improved with steroid and methotrexate 13 years after the start of therapy. The creatine kinase (CK) levels of all patients were decreased along with clinical severity. In conclusion, muscle imaging might be of help for the diagnosis. Treatment with immuno-suppressants could be considered together with steroid from the beginning.

Large-scale Generation of Functional and Transplantable Hepatocytes and Cholangiocytes from Human Endoderm Stem Cells.

The ever-increasing therapeutic and pharmaceutical demand for liver cells calls for systems that enable mass production of hepatic cells. Here we describe a large-scale suspension system that uses human endoderm stem cells (hEnSCs) as precursors to generate functional and transplantable hepatocytes (E-heps) or cholangiocytes (E-chos). hEnSC-derived hepatic populations are characterized by single-cell transcriptomic analyses and compared with hESC-derived counterparts, in-vitro-maintained or -expanded primary hepatocytes and adult cells, which reveals that hepatic differentiation of hEnSCs recapitulates in vivo development and that the heterogeneities of the resultant populations can be manipulated by regulating the EGF and MAPK signaling pathways. Functional assessments demonstrate that E-heps and E-chos possess properties comparable with adult counterparts and that, when transplanted intraperitoneally, encapsulated E-heps were able to rescue rats with acute liver failure. Our study lays the foundation for cell-based therapeutic agents and in vitro applications for liver diseases.

Modelling liver cancer initiation with organoids derived from directly reprogrammed human hepatocytes.

Human liver cancers, including hepatocellular carcinomas and intra-hepatic cholangiocarcinomas, are often diagnosed late with poor prognosis. A better understanding of cancer initiation could provide potential preventive therapies and increase survival. Models for studying human liver cancer initiation are largely missing. Here, using directly reprogrammed human hepatocytes (hiHeps) and inactivation of p53 and RB, we established organoids possessing liver architecture and function. HiHep organoids were genetically engineered to model the initial alterations in human liver cancers. Bona fide hepatocellular carcinomas were developed by overexpressing c-Myc. Excessive mitochondrion-endoplasmic reticulum coupling induced by c-Myc facilitated hepatocellular carcinoma initiation and seemed to be a target of preventive treatment. Furthermore, through the analysis of human intra-hepatic cholangiocarcinoma-enriched mutations, we demonstrate that the RAS-induced lineage conversion from hepatocytes to intra-hepatic cholangiocarcinoma cells can be prevented by the combined inhibition of Notch and JAK-STAT. Together, hiHep organoids represent a system that can be genetically manipulated to model cancer initiation and identify potential preventive therapies.

A Pharmacogenomic Landscape in Human Liver Cancers.

Liver cancers are highly heterogeneous with poor prognosis and drug response. A better understanding between genetic alterations and drug responses would facilitate precision treatment for liver cancers. To characterize the landscape of pharmacogenomic interactions in liver cancers, we developed a protocol to establish human liver cancer cell models at a success rate of around 50% and generated the Liver Cancer Model Repository (LIMORE) with 81 cell models. LIMORE represented genomic and transcriptomic heterogeneity of primary cancers. Interrogation of the pharmacogenomic landscape of LIMORE discovered unexplored gene-drug associations, including synthetic lethalities to prevalent alterations in liver cancers. Moreover, predictive biomarker candidates were suggested for the selection of sorafenib-responding patients. LIMORE provides a rich resource facilitating drug discovery in liver cancers.

Effect of combining ultralow-dose naloxone with morphine in intravenous patient-controlled analgesia: the cut-off ratio of naloxone to morphine for antiemesis after gynecologic surgery.

BACKGROUND/PURPOSE: Admixing an ultralow dose of naloxone with intravenous morphine patient-controlled analgesia (PCA) has been shown to decrease postoperative nausea. However, the cut-off ratio of the naloxone-morphine admixture for antiemetic effects has not been investigated. The purpose of this study was to investigate the cut-off ratio of naloxone-morphine admixture in PCA for antiemesis after gynecologic surgery. METHODS: This double-blind study enrolled 120 female patients who were scheduled for gynecologic surgery under general anesthesia. Patients were randomly allocated to one of three groups (n = 40 for each group). The concentration of naloxone and morphine respectively was 0 microg/mL and 1 mg/mL in group 1, 0.1 microg/mL and 1 mg/mL in group 2 (1:10,000), and 1 microg/mL and 1 mg/mL in group 3 (1:1000). Morphine consumption, verbal rating score of wound pain at rest and with exertion, and morphine-related side effects were investigated at 1, 2, 4 and 24 hours postoperatively. RESULTS: A total of 112 patients completed the study (37 in group 1, 36 in group 2, 39 in group 3). The incidence of nausea during the postoperative 4-24 hours was significantly lower in group 3 than in group 1 (23.1% vs. 56.8%, p < 0.05). Furthermore, the overall incidence of severe nausea was significantly lower in group 3 than in group 1 (2.6% vs. 24.3%, p < 0.05) as was the rescue antiemetic requirements (5.1% vs. 24.3%, p < 0.05). However, there were no significant differences between groups 2 and 1. The pain scores (at rest and with exertion) and 24-hour morphine consumption were not significantly different among the three groups. CONCLUSION: The antiemetic efficacy of ultralow-dose naloxone combined with PCA morphine is limited by a cut-off ratio of naloxone to morphine of 1:10,000.

Contralateral monoarthritis exacerbated chronic constriction injury-induced pain hypersensitivity through upregulating inducible nitric oxide synthase.

INTRODUCTION: High comorbidity of osteoarthritis (OA) and neuropathic pain has been reported in aged patients. Evidence shows that central sensitization of pain processing occurs in late-phase OA and may facilitate the development of neuropathic pain. Few studies reveal whether acute monoarthritis (MA) aggravates neuropathic pain on the opposite side of the body from the injury. METHODS: To address whether neuropathic pain is affected by contralateral MA through distinct inflammatory pathway, MA was induced by intra-articular injection of complete Freund's adjuvant (CFA) into the right tibiotarsal joint, and neuropathic pain was established by chronic constriction injury (CCI) of the left sciatic nerve. RESULTS: We observed that MA aggravated mechanical allodynia and thermal hyperalgesia in CCI rats. Furthermore, MA affected the other side of the spinal cord in multiple aspects, including the upregulation of iNOS mRNA and the enhancement of forskolin-induced facilitation of excitatory synaptic transmission in the spinal cord dorsal horn substantia gelatinosa neurons. DISCUSSION: Interestingly, intrathecal injection of 1400W, an antagonist of iNOS, attenuated intensity of pain behaviors in CCI rats with contralateral MA to similar levels in CCI rats without MA, and also normalized the facilitatory effect of forskolin on excitatory synaptic transmission in the spinal cord dorsal horn neurons in contralateral MA rats. Therefore, contralateral MA worsened CCI-induced pain hypersensitivity probably through upregulating iNOS and enhancing the facilitation of synaptic transmission following CCI. CONCLUSION: Inhibiting the iNOS might be a potential therapeutic strategy for concurrent OA and neuropathic pain.

The natural history of the patients with Duchenne muscular dystrophy in Taiwan: A medical center experience.

BACKGROUND: Duchenne muscular dystrophy (DMD) is the most common hereditary muscular dystrophy and caused by DMD gene mutation. In addition to progressive proximal muscle weakness, respiratory, orthopedic, and gastrointestinal complications are often observed in DMD. The natural history of patients with DMD in Taiwan has not been reported thus far. METHODS: Medical records of 39 patients who received a diagnosis of DMD between 1999 and 2016 at Kaohsiung Medical University Hospital were reviewed. The diagnosis of DMD was confirmed through muscle biopsy or DMD genetic analysis. RESULTS: The mean onset age and mean follow-up period were 2.75 years and 6.76 years, respectively. Seventeen patients (43.5%) had a family history of DMD. The mean full intelligence quotient of the patients was 71.08, and the mean age of walking ability loss was 9.7 years (25 patients). The mean onset age of respiratory insufficiency was 10.64 years with a decline rate of 5.18% per year (25 patients). The mean onset age of cardiomyopathy was 14.69 years (seven patients). The mean onset age of scoliosis was 13.29 years with a progression rate of 11.48° per year (14 patients). Eleven (28.2%) and eight (20.5%) patients had deletions and duplications of DMD, respectively. Fourteen patients (35.9%) had point mutations or small deletions or insertions. Five patients received only multiplex ligation-dependent probe amplification (MLPA) analysis and exhibited neither deletion nor duplication. No mutation was identified in one patient through both MLPA and exon sequencing. CONCLUSION: The clinical phenotypes and disease course in our cohort were consistent with that reported in previous studies. However, the proportion of point mutations or small deletions or insertions in our study was considerably higher than that in reports from other populations. Cardiac ejection fraction was found not a reliable biomarker for identifying cardiac problems, discovering a better parameter is necessary.

In Vitro Expansion of Primary Human Hepatocytes with Efficient Liver Repopulation Capacity.

Transplantation of human hepatocytes (HHs) holds significant potential for treating liver diseases. However, the supply of transplantable HHs is severely constrained by limited donor availability and compromised capacity for in vitro expansion. In response to chronic injury, some HHs are reprogrammed into proliferative cells that express both hepatocyte and progenitor markers, suggesting exploitable strategies for expanding HHs in vitro. Here, we report defined medium conditions that allow 10,000-fold expansion of HHs. These proliferating HHs are bi-phenotypic, partially retaining hepatic features while gaining expression of progenitor-associated genes. Importantly, these cells engraft into injured mouse liver at a level comparable to primary HHs, and they undergo maturation following transplantation in vivo or differentiation in vitro. Thus, this study provides a protocol that enables large-scale expansion of transplantable HHs, which could be further developed for modeling and treating human liver disease.