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PubMed1998

Studies of brush border enzymes, basement membrane components, and electrophysiology of tissue-engineered neointestine.

BACKGROUND/PURPOSE: Previous studies have shown that intestinal crypt cell transplantation using biodegradable scaffolds can generate stratified epithelium reminiscent of embryonic gut. The authors propose to tissue engineer small intestine on biodegradable scaffolds by transplanting intestinal epithelial organoid units, which maintain the epithelial mesenchymal cell-cell interaction necessary for epithelial survival, proliferation, and differentiation. METHODS: Intestinal epithelial organoid units were isolated from neonatal Lewis rats by enzyme digestion and differential sedimentation. Organoid units were seeded on to tubular scaffolds made of nonwoven polyglycolic acid (PGA) sprayed with 5% polylactic acid (PLA). Polymers either were coated (28 constructs) or noncoated (33 constructs) with collagen type I. A total of 61 organoid unit polymer constructs were implanted into 61 animals. Animals were killed and constructs harvested at 2, 6, 7, 8, 9, 10, 12, and 14 weeks. RESULTS: Histological analysis showed formation of neomucosa characterized by columnar epithelium with goblet, and paneth cells were evident in 47 of the 61 constructs. The outer walls were composed of fibrovascular tissue, degradable polymer, extracellular matrix, and smooth muscle-like cells. Immunofluorescent microscopy showed apical staining of brush border enzymes, sucrase and lactase, and basolateral staining for laminin, indicating the establishment of cell polarity. Electrophysiology of Ussing-chambered neomucosa and adult ileal mucosa exhibited similar transepithelial resistance. CONCLUSION: These results suggest that intestinal crypt cells heterotopically transplanted as epithelial organoid units on PGA-PLA tubular scaffolds can survive, reorganize, and regenerate complex composite tissue resembling small intestine demonstrating organ morphogenesis, cytodifferentiation, and phenotypic maturation.

Animals↗
PubMed1988

Opposite effects of 1,25(OH)2D3 on synthesis and release of PTH compared with secretory protein I.

Aggregates of bovine parathyroid cells (organoids) were cultured with or without 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and examined for effects on the synthesis, cellular content, and release of parathyroid hormone (PTH) and secretory protein I. Organoids cultured with 120 pM 1,25(OH)2D3 at 1.35 mM calcium contained 27 +/- 2% (mean +/- SE) less and released 26 +/- 7% less PTH and contained 21 +/- 2% more and released 49 +/- 16% more secretory protein I than untreated organoids. After 15-min incubations with radioactive leucine, treated organoids incorporated 25 +/- 2% less radioactivity into precipitable cellular proteins than did untreated organoids, indicating that the overall synthetic rate of proteins was decreased by 1,25(OH)2D3 at 1.35 mM calcium. After separation of cellular proteins by gel electrophoresis, analysis of individual protein bands indicated that the mean treated-control ratio for proparathyroid hormone radioactivity was 0.88 +/- 0.06 (P less than 0.10) while that for secretory protein I was 1.56 +/- 0.17 (P less than 0.01), respectively. Experiments were performed at 1.2, 12, 120, and 1,200 pM 1,25(OH)2D3 and both 1.4 and 1.8 mM calcium. In both cases, increasing levels of 1,25(OH)2D3 progressively decreased PTH synthesis and release and progressively increased that of secretory protein I, significant effects being observed at 1.2 pM 1,25(OH)2D3. We conclude that at physiological calcium levels, 1.2-1,200 pM 1,25(OH)2D3 suppresses the synthesis and secretion of PTH, increases that of secretory protein I, and at similar concentrations decreases the overall protein synthetic rate compared with untreated controls.

Animals↗
PubMed1987

Epidermal growth factor stimulates the synthesis of cell-attachment proteins in the human breast cancer cell line PMC42.

The human breast cancer cell line PMC42 responds to the addition of epidermal growth factor (EGF) by proliferation and increased frequency of attachment of cell-organoid structures to the culture vessel. Antibodies to fibronectin and laminin reacted strongly, by immunoperoxidase, with the membranes of cells from organoids that became adherent following addition of EGF. This reaction was weak with membranes of cells of non-adherent organoids in cultures containing EGF and was negative with membranes of cells of free-floating organoids from cultures without EGF. An increase in biosynthetic labelling with 35S-methionine was found in cell lysates and supernatants of PMC42 cells cultured in the presence of EGF compared with control cells grown without EGF. One-dimensional SDS-polyacrylamide gel electrophoresis and 2-dimensional NEPHGE-PAGE of labelled cell proteins showed increased synthesis of several cellular proteins and the appearance in EGF-treated cells of 2 proteins which were not detected in cells from control cultures lacking EGF. Immunoprecipitation experiments using antibodies to fibronectin and laminin with lysates of 35S-methionine labelled PMC42 cells cultured with EGF showed strong immunoprecipitation at Mr 200 and 400 with anti-laminin, and at Mr 200 and 96 with anti-fibronectin. These immunoprecipitates were blocked specifically by purified laminin or fibronectin, respectively. No immunoprecipitates were detected with these antibodies in lysates from cells grown without EGF. EGF thus stimulates increased adherence of cultured PMC42 cell-organoid structures together with increased membrane expression of the cell-adhesive proteins laminin and fibronectin. These effects may play a role in normal development and neoplastic behaviour of breast epithelia.

Breast Neoplasms↗
PubMed2000

Established histological identity and cell destruction treatments for cancer.

During cancerous cell turnover activity maintained by two types of mitosis, maturation and heteroduplication, cancer tissue consists of two types of cells, maturable and non-maturable. Most of the tissue is composed of maturable cells, which eventually disappear in the terminally matured cell phase. These cells do not participate in cell turnover activity or the organoid identity of cancer tissue. However, a small portion of the tissue is comprised of non-maturable cells, which replicate themselves endlessly, while producing maturable cells through each mitotic division in hetero-duplication mitosis. Thus, cell turnover activity and organoid identity are established in the cancer tissue. This organoid identity is solely responsible for carcinogenesis. Since most typical features of cancer are only detectable in maturable cells during maturation mitosis, cell destruction targeting these features should not be regarded as eradication. To eradicate cancer, the organoid identity of cancer, which is only established by heteroduplication mitosis, should clearly be recognized, and a new concept of cancer treatment based on destruction of the organoid identity should be devised in the future. This does not appear to be an insurmountable task.

Cell Differentiation↗
PubMed1994

Apoptosis induced by inhibition of intercellular contact.

The LIM 1863 colon carcinoma cell line grows as structural organoids of goblet and columnar cells around a central lumen and provides a model for the development of stem cells in the normal colon. The organoid structure can be disrupted by removal of calcium from the medium, resulting in a suspension of single cells. Upon readdition of calcium, the cells reform the organoid structure over a period of 24 h, and ultrastructural examination of the reforming cells reveals that this involves a complex process that we have termed clutching. To determine the adhesion molecules involved in organoid formation we attempted to block this process by single cell suspensions of LIM 1863 reseeded in the presence of monoclonal antibodies. An anti-integrin antibody directed against a conformational epitope on the alpha v subunit totally inhibited organoid reformation. As a consequence of this inhibition of cell contact the colon carcinoma cells rapidly underwent apoptosis. Investigations of the apoptotic pathway involved suggested an induction mechanism since the onset of apoptosis in the contact-inhibited cells showed specific increased synthesis of 68- and 72-kD proteins. In addition, immunoblotting of cytosolic and nuclear extracts of the cells revealed the rapid translocation of the tumor suppressor gene product, p53 to the cell nucleus upon induction of apoptosis. These results suggest that cell-cell adhesion may be a vital regulator of colon development overcome in tumor cells by loss of adhesion molecules or of functional p53 protein.

Apoptosis↗
PubMed1998

Thymomas and thymic carcinomas. Evaluation of the Müller-Hermelink classification.

In the present study the Müller-Hermelink classification was used to analyze 39 thymomas and 4 thymic carcinomas collected over 20 years at the Chair and Department of Pathomorphology CM UJ. Our series consisted of 10 medullary thymomas (25.6%), 13 mixed (33.3%), 7 organoid (17.9%) and 9 cortical thymomas (23.0%). The mean age of the patients was 50.3 and it was the highest in patients with mixed thymomas-58.4 years and the lowest in patients with organoid thymomas-38.9 years, the difference being statistically significant. In the present series women were predominant (24:15). Myasthenia gravis was observed in 10 patients (25.6%), 5 women and 5 men, in 7 of them it was associated with cortical and organoid thymomas. Medullary, mixed and organoid thymomas were usually of lower stage (I and II), having a better prognosis than cortical thymomas and thymic carcinomas. One organoid thymoma recurring after 7 years evolved into cortical thymoma. Two thymic carcinomas were diagnosed as anaplastic, low differentiated, one as sarcomatous and one as well differentiated squamous carcinoma. The mean age of the patients was 39.7 years. The prognosis in all the patients with thymic carcinoma was poor. Based upon personal experience the authors regard the Müller-Hermelink classification as useful, easy to apply, reproducible and providing important prognostic information.

Adult↗
PubMed1985

[Quantitative indicators of gentamicin and sisomicin interaction with isolated subcellular fractions of the liver and kidneys and intracellular distribution of these antibiotics].

Interaction of gentamicin and sisomicin with isolated subcellular fractions of the rat liver and the kidney cortical layer was studied. Distribution of the antibiotics was investigated in a system with the volume ratio of the main components (organoids and cytosol-dissolved drug) simulating the natural volume ratio of the cytoplasm and organoids in the cells. It was shown that lysosomes were the most active elements in binding antibiotics. The microsomes and mitochondria were less active. By the binding capacity the subcellular structures of the kidneys were superior to the analogous structures of the liver. Dissociation of the organoid complexes with the antibiotics was possible, the mobility of the sisomicin complexes being higher than that of the gentamicin complexes. During intracellular distribution the major amount of every of the above aminoglycosides was absorbed by the organoids. Up to 20 per cent of gentamicin and up to 30 per cent of sisomicin remained in the cytoplasm in the active form. The characteristic features of the intracellular distribution of sisomicin (build up of high levels of the free antibiotic in the cytoplasm and relatively easy dissociation of the antibiotic complexes with the organoids of the kidney cortical layer) may define the higher activity of sisomicin as compared to that of gentamicin against intracellularly located microorganisms and its lower potential nephrotoxicity.

Animals↗
PubMed2025

Weifuchun ( ) exerts therapeutic effects on gastric fundic gland polyps by promoting ferroptosis.

OBJECTIVE: To investigate the therapeutic effects of Chinese medicine Weifuchun (WFC, ) on gastric fundic gland polyps (FGPs). METHODS: FGPs organoids were constructed with patients-derived samples. The morphology and size of FGPs organoids were detected using bright-field imaging. Effective components and corresponding potential targets of WFC were screened using multiple open-source databases and research on Traditional Chinese Medicine or compound formulas. Core genes were identified through protein-protein interaction networks. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses of the core genes were conducted. The interactions between main components and core targets were analyzed through the FerrDb database. The expressions of core targets were detected by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: After WFC treatment, the number and size of FGPs organoids were significantly reduced. Twenty nine active drug components and 162 candidate targets of WFC for treating FGPs were identified, including 37 targets related to ferroptosis. Quercetin, Glaucocalyxin B, Melissoidesin U, Melissoidesin O, Hesperetin, Glaucocalyxin A, Angustifolin, Melissoidesin M, Di-n-octyl phthalate, and beta-sitosterol were identified as the main active compounds. SRC proto-oncogene, non-receptor tyrosine kinase, signal transducer and activator of transcription 3, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit beta, phosphoinositide-3-kinase regulatory subunit 1, and AKT serine/threonine kinase 1 were identified as the primary targets. KEGG pathways related to carcinogenesis, cell proliferation and metabolism, and oxidative stress. WFC promoted FGPs organoids' death and could be reversed by ferroptosis inhibitor of Erastin. The qRT-PCR results showed that WFC treatment could regulate the mRNA expression levels of solute carrier family 7 member 11, acyl-CoA synthetase long chain family member 4, and arachidonate 15-lipoxygenase, type B. CONCLUSION: WFC may exert its therapeutic effects by inducing ferroptosis in FGPs cells.

Humans↗
PubMed1992

A new approach for realizing the "antioncogram".

On the basis of an organoid culture method which allows organoid reorganization and histotypical growth of human carcinomas under in vitro conditions, we propose in the present study an organoid culture assay (OCA) as "antioncogram", i.e., as in vitro model for testing the drug sensitivity and resistance of individual patients' carcinomas previous to clinical chemotherapy. At the beginning of the assay, specimens of human carcinomas are disaggregated to dense single cell suspensions and dropped on a filter sheet at the air-medium interface. Organoid culture nodules develop within several days to weeks. They are exposed to cytostatics by adding the drugs for 2-3 days to the growth medium below the filter sheet. At the end of the exposure period, the cytotoxic effects are estimated by determining the fraction of viable cells, measured by the uptake of neutral red in relation to the total cell mass. In the present study we could show that this assay actually reflects the different levels of experimentally induced resistance of three human carcinoma strains of an epidermoid hypopharynx carcinoma to the cytostatic drug cisplatin and is obviously suited to predict the response of individual human carcinomas to chemotherapy in a rapid and feasible manner.

Carcinoma, Squamous Cell↗
PubMed2026

Application of emerging technologies in the antiviral field.

Viral diseases pose a serious threat to global public health, agriculture, and biosecurity. Conventional antiviral strategies are often limited by an incomplete understanding of disease mechanisms, poor targeting precision, and slow response times. Emerging technologies are now reshaping the landscape of antiviral research. This review examines the roles of four key frontiers, including organoid models, gene editing, AI-driven molecular design, and synthetic biology. Organoids provide physiologically relevant platforms that model virus-host interactions and disease progression. Viral infections remain a major challenge to human and animal health, agriculture, and biosecurity. Progress in antiviral research is constrained by the complexity of viral pathogenesis, the diversity and rapid evolution of viruses, and the limited translational relevance of some traditional model systems. Recent advances in organoid technology, gene editing, artificial intelligence, and synthetic biology are expanding the toolkit available for antiviral research and development. In this review, we discuss how these four technological frontiers contribute to disease modeling, target discovery, molecular design, and translational innovation. Organoids, in particular, provide physiologically relevant systems for investigating viral infection, tissue tropism, host responses, and pathogenesis. Gene editing tools, such as CRISPR, enable precise manipulation of host and viral genomes, facilitating the development of resistant organisms and next-generation vaccine platforms. AI technologies, including AlphaFold for structure prediction and platforms for de novo protein design, address long-standing bottlenecks in structural biology and offer powerful means to engineer antiviral proteins, antibodies, and vaccine antigens. Synthetic biology, guided by the Design-Build-Test-Learn cycle, integrates computational design, genetic assembly, and functional validation into a cohesive pipeline. Together, these technologies form a synergistic workflow that spans disease modeling, target discovery, molecular design, construction, testing, and iterative optimization. This integrated approach is shifting antiviral development from traditional empirical methods toward more precise, intelligent strategies. The review also highlights ongoing challenges in integration and scalability, stressing that high-quality biological datasets and stronger interdisciplinary collaboration are essential for realizing translational potential. By presenting a cohesive view of these converging methodologies, this review offers a framework to guide the intelligent evolution of antiviral strategies in both human and animal health.

Antiviral↗
PubMed1992

Human ovarian surface epithelial cells are capable of physically restructuring extracellular matrix.

OBJECTIVE: After ovulation the human ovarian surface epithelium proliferates at the wound edges, migrates over the ovulatory defect, and contributes to its repair primarily by the action of proteolytic enzymes and by the deposition of new matrix material. We examined the potential for human ovarian surface epithelial cells to physically remodel extracellular matrix in culture, similar to collagen gel lattice contraction by fibroblasts, a well-known culture model for wound repair, as an additional role of human ovarian surface epithelium in wound repair. STUDY DESIGN: Human ovarian surface epithelium cells from ovarian biopsies of 11 patients were grown in culture and plated onto a combination of collagen gel and rat ovarian surface epithelial-derived extracellular matrix. The degree of matrix contraction was measured as the percentage of the original culture diameter. RESULTS: Human ovarian surface epithelial cells surrounded and contracted the combination of matrices into a dense matrix organoid. The degree of organoid contraction was related to the number of human ovarian surface epithelial cells plated per organoid and to the inclusion of fibroblasts within the collagen gel but was not affected either by adding epidermal growth factor and hydrocortisone to the culture medium or by reducing the serum component of the medium. CONCLUSION: Human ovarian surface epithelial organoids may be useful for the study of normal and abnormal ovarian events such as ovulatory wound repair and cyst formation.

Adult↗
PubMed2025

Dysregulation of mTOR signalling is a converging mechanism in lissencephaly.

Cerebral cortex development in humans is a highly complex and orchestrated process that is under tight genetic regulation. Rare mutations that alter gene expression or function can disrupt the structure of the cerebral cortex, resulting in a range of neurological conditions1. Lissencephaly ('smooth brain') spectrum disorders comprise a group of rare, genetically heterogeneous congenital brain malformations commonly associated with epilepsy and intellectual disability2. However, the molecular mechanisms underlying disease pathogenesis remain unknown. Here we establish hypoactivity of the mTOR pathway as a clinically relevant molecular mechanism in lissencephaly spectrum disorders. We characterized two types of cerebral organoid derived from individuals with genetically distinct lissencephalies with a recessive mutation in p53-induced death domain protein 1 (PIDD1) or a heterozygous chromosome 17p13.3 microdeletion leading to Miller-Dieker lissencephaly syndrome (MDLS). PIDD1-mutant organoids and MDLS organoids recapitulated the thickened cortex typical of human lissencephaly and demonstrated dysregulation of protein translation, metabolism and the mTOR pathway. A brain-selective activator of mTOR complex 1 prevented and reversed cellular and molecular defects in the lissencephaly organoids. Our findings show that a converging molecular mechanism contributes to two genetically distinct lissencephaly spectrum disorders.

Humans↗
PubMed1997

Characterization of novel cell lines from pleomorphic adenomas of the parotid gland established in a collagen gel system.

The pathobiology of salivary neoplasms can best be studied in a model system that reflects the native state of the tumor. The present study describes the use of a three-dimensional collagen gel (organoid) system in which pleomorphic adenomas of the parotid gland were propagated in vitro. Five pleomorphic adenoma cultures were established as organoid gels and compared with touch-preparations or cryopreserved specimens of native tumor. The organoid cultures demonstrated normal DNA content, the expression of myoepithelial cell proteins, and the production of sulfated acid mucins; these cellular and secretory features mimicked those found in the archival specimens. Further, organoid cultures of pleomorphic adenoma could be initiated after monolayer culture, demonstrating that culture on a plastic support does not alter the nature of the cells. Development of an in vitro culture system that maintains the native state of pleomorphic adenoma is an important tool for studying the pathobiology of these tumors.

Actins↗
PubMed2005

Three-dimensional polarization sensitizes hepatocytes to Fas/CD95 apoptotic signalling.

Maintenance of epithelial cell shape and polarity determines many vital cell functions, including the appropriate response to external stimuli. Murine hepatocytes cultured in a three-dimensional Matrigel matrix formed highly polarized organoids characterized by specific localization of an ERM (ezrin/radixin/moesin) protein, radixin, at microvillus-lined membrane domains. These apical domains surrounded a lumen and were bordered by tight junctions. The hepatocyte organoids were functional as judged by the high level of albumin secretion and accumulation of bilirubin. Stimulation of the Fas/CD95 death receptor, which is highly hepatotoxic in vivo, was a strong inducer of apoptosis in the polarized organoids. This was in sharp contrast to the monolayer hepatocyte cultures, which were protected from death by exacerbated NF-kappaB signalling following engagement of the death receptors. Thus, hepatocytes in polarized, functional organoids modulate an intracellular signal transduction pathway, allowing the recapitulation of their physiological response to an apoptotic stimulus.

Animals↗
PubMed1994

Thymoma. Histologic subclassification is an independent prognostic factor.

BACKGROUND: Several histologic classifications of thymomas have been proposed, and attempts have been made to correlate the different histologic subtypes to clinical behavior and prognosis. Recently, Marino and Müller-Hermelink and Kirchner et al. proposed a new morphologic classification of thymomas based on the resemblance of the neoplastic cells to subtypes of the normal thymic epithelial cells. In this classification, six categories of thymic epithelial tumors are recognized. They define four categories of thymoma: medullary, mixed, organoid (predominantly cortical), and cortical, and two subgroups of thymic carcinomas: well differentiated thymic carcinoma and high grade carcinomas. METHODS: The authors studied 116 patients with thymic epithelial tumors classified according to the proposals of Marino and Müller-Hermelink and Kirchner et al. to assess the effect of histologic classification and other factors (stage, size of tumor, lymphoid hyperplasia, myasthenia gravis, age, sex, and treatment) on survival, and freedom from relapse. RESULTS: Eight cases (7%) were medullary, 32 cases (28%) mixed, 20 cases (17%) organoid (predominantly cortical), 21 cases (18%) cortical, 29 cases (25%) well differentiated carcinoma (WDTC), two cases (2%) high grade carcinoma, and four cases (3%) unclassifiable. Fifty-two patients were in stage I, 32 stage II (16 IIA, 16 IIB), 28 stage III, and four Stage IVA. Only stage (P = 0.0001; hazard ratio = 5.36) and histology (P = 0.0019; hazard ratio = 8.010) were significant in predicting recurrence. Histology was highly correlated with stage, but by multivariate analysis was an independent factor in predicting relapse (P = 0.0281; hazard ratio = 5.92). None of the medullary or mixed thymomas recurred, even though 30% were invasive. Patients with WDTC recurred more often and earlier than patients with organoid and cortical thymoma (log rank, P = 0.0001). The actuarial freedom from relapse for patients with WDTC was 58% at 5 years and 46% at 10 years compared with 100% for other subtypes. Both advanced stage (III and IV) and the WDTC histologic subtype significantly increased the risk of death from thymoma (log rank, P = 0.0001). The actuarial survival of patients with WDTC was 80% at 5 years and 54% at 10 years, whereas that of patients with the other subtypes was 100% at 5 and 10 years. Five of seven relapses and six of seven deaths from thymoma occurred in patients with WDTC. In Stage II patients, one of 16 minimally invasive (Stage IIA) tumors recurred, compared with 3 of 16 grossly invasive (Stage IIB) tumors, indicating that microscopic assessment of invasion is important in staging. CONCLUSIONS: The histologic classification of Marino and Müller-Hermelink has prognostic significance, independent of tumor stage. Medullary and mixed thymomas were benign tumors with no risk of recurrence, even when capsular invasion was present. Organoid and cortical thymoma showed intermediate invasiveness and a low, but significant, risk of late relapse, even with minimal invasion. WDTC were always invasive and had a significantly increased risk of relapse and death, even for Stage II patients. Adjuvant therapy appears unnecessary for medullary and mixed thymomas, even when invasive.

Adolescent↗
PubMed1987

Human breast epithelium in vitro: the re-expression of structural and functional cellular differentiation in long-term culture.

Fragments of human breast epithelium, devoid of all stromal and basal lamina components, which maintain their in vivo topological organisation can be cultured for up to 28 days within a reconstituted rat-tail-derived collagen matrix. These organoids initially undergo a loss of structural and 3-dimensional organisation, typified by loss of lumina formed by epithelial cells, and myosin from myoepithelial cells. Their subsequent reorganisation is dependent on the presence of serum, insulin, hydrocortisone, and cholera toxin in tissue culture medium. After this preliminary phase, a reduction in the concentration of serum, insulin, hydrocortisone, and cholera toxin is necessary to allow the structural differentiation of epithelial and myoepithelial cells. The myoepithelial cells also regain their ability to produce the basal lamina component laminin. The use of bovine-dermal collagen as the matrix, rather than rat-tail-derived collagen is shown to result in more stable organisation and differentiation of the organoids. The successful use of single-cell pellets (derived by trypsinisation of the organoids) in place of organoids in such cultures illustrates that there is no requirement for pre-existing cell/cell contact or topological organisation of cells prior to embedding within the collagen matrix.

Breast↗
PubMed1989

Influence of human breast development on the growth properties of primary cultures.

In experimental animal models the susceptibility of the mammary gland to neoplastic transformation is related to its degree of development and proliferative activity; this observation led us to determine whether the human breast epithelium also exhibits development-related differences, and whether these differences could be detected in an in vitro system. Normal breast tissue obtained from reduction mammoplasties of 9 patients ranging in age from 18 to 56 years were characterized in both whole mount preparations and organoids obtained after collagenase-hyaluronidase digestion by their degree of development based upon the types of lobules present. Lobules were classified into type 1 (Lob 1), composed of approximately 11 alveolar buds, the less developed; lobules type 2 (Lob 2), of moderate development, composed of approximately 47 ductules each, and lobules type 3 (Lob 3), composed of 80 ductules each, represented the highest level of development. Epithelial organoids obtained after digestion were plated in DMEM:F12 medium supplemented with hydrocortisone, cholera toxin, insulin and 5% horse serum with a calcium concentration of 1.05 mM Ca++. Following attachment, the medium was replaced by medium containing 0.040 mM Ca++. The percentage of attachment of organoids to the flask was greater in cells from Lob 1 (89-99%) and Lob 1+2 (79-100%) than in cells from Lob 3, which had a 53-67% attachment. The total yield of cells after 7 weeks in culture was also greater in cells derived from Lob 1 and Lob 1+2 than in cells from Lob 3. The total yield of cells obtained from primary cultures was not related to the number of organoids plated, but to the degree of development of the gland. The DNA-labeling index (DNA-LI) in intact breast tissue correlated with that in primary cultures; it was greater in Lob 1 and Lob 1+2 than in Lob 3. By flow cytometry, the highest percentage of cells in S-phase was seen in cells with the highest DNA-LI. We concluded that the growth characteristics of mammary epithelial cells in vitro in a low Ca++ medium is modulated by the degree of development and differentiation of the gland.

Adult↗
PubMed2005

Coordinated movement of bile canalicular networks reconstructed by rat small hepatocytes.

Hepatocytes in vivo have a potential for liver regeneration, but it has been very difficult to reconstruct hepatic organoids in vitro. Recent studies have shown that small hepatocytes (SHs) can reconstruct hepatic organoids including functional bile canaliculi (BC). In the present study we analyzed the movement of BC formed in the hepatic organoids, focusing on the coordination of contraction and dilation among cells and the mechanism producing the coordination. Hepatic cells, including SHs, were isolated from an adult rat liver and cultured. Time-lapse images of BC movements were taken and analyzed in cells treated with or without cytochalasin B (CB). Time-lapse images revealed that all BC, regardless of region contracted in a coordinated manner. Actin filaments were observed along the BC even after the BC networks treated with CB dilated markedly. Microinjection of dye was also carried out to investigate the flow thorough BC. Secreted fluorescein from the injected cell flowed along BC, and gap junctional protein connexin 32 was expressed along BC networks, suggesting cell-to-cell communication. Thus, groups of hepatocytes in the hepatic organoids act in a coordinated manner through intercellular communication.

Animals↗