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PubMed1984

Rearrangements of host and viral DNA in mouse cells transformed by simian virus 40.

We have determined the structure of host DNA and viral DNA at the site of integration of Simian virus 40 (SV40) in a line of transformed Balb/c-3T3 cells (SVB400) isolated by single cell cloning after virus infection. Recombinant phage containing integrated viral DNA and flanking host DNA were purified from a genomic library and, in conjunction with restriction endonuclease cleavage analysis of the transformed cell DNA, were used to determine the organization of the integrated viral sequences. There is heterogeneity in the arrangement of the viral sequences resulting from tandem duplications of all or part of the SV40 genome with preservation of the viral-host junctions. The predominant arrangement is the result of tandem duplication of 41% of the SV40 genome from 0.64 to 0.23. Analysis of the structure of integrated viral DNA in SVB400 at different passage numbers and in single cell clones derived from the 20th passage indicated that rearrangements of viral DNA occur after the integration event and continue with passage of the cells. The organization of host sequences before and after the integration of SV40 was determined by restriction endonuclease cleavage analysis of parental 3T3 DNA and SVB400 DNA, and by analysis of recombinant phage isolated from genomic libraries. A deletion of at least 15 X 10(3) bases of host DNA occurred at the site of integration, which indicates that viral integration was not a result of a simple insertion of SV40. Nucleotide sequence analysis of the virus-host junctions showed that retained SV40 sequences were colinear with the viral genome, and that the junctions with SV40 DNA occurred at nucleotide numbers 1377 and 3610. There was no evidence of duplications of viral or host sequences at the junctions, and a comparison of the flanking mouse sequences with the deleted SV40 sequences revealed no significant homology at the point of joining of the two genomes.

Animals↗

PubMed2025

Spatial transcriptomics-aided localization for single-cell transcriptomics with STALocator.

Single-cell RNA-sequencing (scRNA-seq) techniques can measure gene expression at single-cell resolution but lack spatial information. Spatial transcriptomics (ST) techniques simultaneously provide gene expression data and spatial information. However, the data quality of the spatial resolution or gene coverage is still much lower than the quality of the single-cell transcriptomics data. To this end, we develop a ST-Aided Locator for single-cell transcriptomics (STALocator) to localize single cells to corresponding ST data. Applications on simulated data showed that STALocator performed better than other localization methods. When applied to the human brain and squamous cell carcinoma data, STALocator could robustly reconstruct the relative spatial organization of critical cell populations. Moreover, STALocator could enhance gene expression patterns for Slide-seqV2 data and predict genome-wide gene expression data for fluorescence in situ hybridization (FISH) and Xenium data, leading to the identification of more spatially variable genes and more biologically relevant Gene Ontology (GO) terms compared with the raw data. A record of this paper's transparent peer review process is included in the supplemental information.

Single-Cell Analysis↗

PubMed2003

Inhibitory and stimulatory regulation of Rac and cell motility by the G12/13-Rho and Gi pathways integrated downstream of a single G protein-coupled sphingosine-1-phosphate receptor isoform.

The G protein-coupled receptors S1P2/Edg5 and S1P3/Edg3 both mediate sphingosine-1-phosphate (S1P) stimulation of Rho, yet S1P2 but not S1P3 mediates downregulation of Rac activation, membrane ruffling, and cell migration in response to chemoattractants. Specific inhibition of endogenous Galpha12 and Galpha13, but not of Galphaq, by expression of respective C-terminal peptides abolished S1P2-mediated inhibition of Rac, membrane ruffling, and migration, as well as stimulation of Rho and stress fiber formation. Fusion receptors comprising S1P2 and either Galpha12 or Galpha13, but not Galphaq, mediated S1P stimulation of Rho and also inhibition of Rac and migration. Overexpression of Galphai, by contrast, specifically antagonized S1P2-mediated inhibition of Rac and migration. The S1P2 actions were mimicked by expression of V14Rho and were abolished by C3 toxin and N19Rho, but not Rho kinase inhibitors. In contrast to S1P2, S1P3 mediated S1P-directed, pertussis toxin-sensitive chemotaxis and Rac activation despite concurrent stimulation of Rho via G12/13. Upon inactivation of Gi by pertussis toxin, S1P3 mediated inhibition of Rac and migration just like S1P2. These results indicate that integration of counteracting signals from the Gi- and the G12/13-Rho pathways directs either positive or negative regulation of Rac, and thus cell migration, upon activation of a single S1P receptor isoform.

3T3 Cells↗

PubMed1998

Osteoprogenitor cells as targets for ex vivo gene transfer.

We transduced osteoprogenitor cells with recombinant retrovirus and analyzed proviral integration patterns into chromosomal DNA to detect for the first time the clonal and cellular fate of osteoprogenitor-derived progeny cells. Metaphyseal bone cells and diaphyseal stromal cells were isolated from the distal femurs of young rats, transduced with the vM5neolacZ recombinant retrovirus, and selected in the neomycin analog, G418. Following surgical marrow ablation of a femur in one leg of mature rats, retroviral-transduced metaphyseal or diaphyseal cells were injected into the ablated site. These rats were killed 5-6 days later. Metaphyseal and diaphyseal cells were isolated from distal femurs, selected in G418, and stained for beta-galactosidase (beta-gal+). The number and clonal origin of transduced progenitor cells were determined. High numbers of beta-galactosidase colonies with an osteoblast phenotype were obtained following metaphyseal transplants and detected in 100% of metaphyseal and none of diaphyseal specimens. In contrast, beta-galactosidase colonies derived from diaphyseal transplants were detected in 50% of specimens in both the metaphysis and diaphysis, and the absolute number of progenitor cell colonies was 60-fold less than metaphyseal transplants. Provirus was only detected in the ablated bones and not in the contralateral bone or other tissues. Proviral integration fragment analysis showed a single integration site for recovered metaphyseal cell clones, consistent with their origination from a common single progenitor. This is one of the first demonstrations of successful transplantation of clonal osteoprogenitors to their site of origin in bone. It may be possible to use these cells to target genes to bone for therapeutic use in skeletal and hematopoietic diseases.

Animals↗

PubMed1987

Unusual sequence element found at the end of an amplicon.

In a polyomavirus-transformed rat cell line, designated LPT, the polyomavirus DNA is integrated into a single chromosomal site. Treatment of LPT cells with carcinogens induces amplification of the integrated virus DNA and flanking cellular sequences. We show that the amplification is arrested within a specific cell DNA segment that maps 1.3 to 1.85 kilobases beyond one virus-cell DNA junction, defined as the left junction. We also present the sequence of an 897-base-pair fragment spanning the arrest site. This fragment contains an unusual sequence element, which consists of two contiguous components, a potential cruciform with stems of 6 base pairs and a d(G-A)27 X d(T-C)27 tract, and maps 1,497 to 1,564 nucleotides beyond the left junction. The possibility that this unusual sequence plays a role in the arrest of the amplification process is discussed.

Animals↗

PubMed2000

Sorting out bacterial viability with optical tweezers.

We have developed a method, using laser, optical tweezers and direct microscopic analysis of reproductive potential and membrane integrity, to assess single-cell viability in a stationary-phase Escherichia coli population. It is demonstrated here that a reduction in cell integrity, determined by using the fluorescent nucleic acid stain propidium iodide, correlated well with a reduction in cell proliferating potential during the stationary-phase period studied. Moreover, the same cells that exhibited reduced integrity were found to be the ones that failed to divide upon nutrient addition. A small but significant number of the intact cells (496 of 7,466 [6.6%]) failed to replicate. In other words, we did not find evidence for the existence of a large population of intact but nonculturable cells during the stationary-phase period studied but it is clear that reproductive ability can be lost prior to the loss of membrane integrity. In addition, about 1% of the stationary-phase cells were able to divide only once upon nutrient addition, and in a few cases, only one of the two cells produced by division was able to divide a second time, indicating that localized cell deterioration, inherited by only one of the daughters, may occur. The usefulness of the optical trapping methodology in elucidating the mechanisms involved in stationary-phase-induced bacterial death and population heterogeneity is discussed.

Escherichia coli↗

PubMed2026

Pharmacologic inhibition of SOX9-CDK4 by CYD-4-61 impairs gastric adenocarcinoma growth and amplifies anti-PD-1 response.

Gastric adenocarcinoma (GAC) remains a leading cause of cancer-related mortality, particularly in patients with peritoneal carcinomatosis, for whom effective therapies are limited. We investigated the therapeutic efficacy and molecular mechanism of CYD-4-61, a BAX activator, using human GAC cell lines, patient-derived xenograft models, genetically engineered mouse models, and a syngeneic mouse model. CYD-4-61 potently inhibited tumor cell proliferation, induced apoptosis, and suppressed cancer stem cell-like properties, with enhanced activity in radiation-resistant GAC cells. Mechanistically, CYD-4-61 activated the BAX-caspase pathway, leading to SOX9 protein reduction. Integrated bulk and single-cell transcriptomic analyses identified SOX9-dependent transcriptional programs as major targets of CYD-4-61. Functional rescue experiments together with chromatin immunoprecipitation and CUT&RUN analyses supported CDK4 as a SOX9-regulated gene and demonstrated suppression of the SOX9-CDK4 regulatory axis following CYD-4-61 treatment. In multiple preclinical models, CYD-4-61 significantly inhibited tumor growth and improved the therapeutic response to anti-programmed cell death protein 1 (PD-1) therapy while modulating the tumor immune microenvironment. Clinically, co-expression of SOX9 and CDK4 was associated with diffuse-type GAC and poor patient outcomes. These findings identify the BAX-SOX9-CDK4 axis as an important mechanism contributing to the antitumor activity of CYD-4-61 and provide a strong preclinical rationale for its further development as a therapeutic strategy for aggressive GAC.

Animals↗

PubMed1986

Efficient transformation and frequent single-site, single-copy insertion of DNA can be obtained in mouse erythroleukemia cells transformed by electroporation.

Electroporation has recently been shown to have advantages over the commonly used method of calcium phosphate precipitation for obtaining DNA-mediated transformation of certain types of cells. Although mouse erythroleukemia cells and other cells of hematopoietic origin are not transformed at useful frequencies by calcium phosphate-DNA precipitation methods, we obtained high frequencies of transformation (approximately 10(-5)) of these cells with electroporation. Even higher transformation frequencies (approximately 10(-3)) were obtained with human fibroblasts. Another advantage of electroporation was found when analysis of Southern blots of DNA from 243 transformed erythroleukemia cell colonies indicated that, under appropriate conditions, about 79% of the transformed cells had the exogenous DNA integrated in single copies at single sites. Under conditions of higher DNA and lower cell concentrations using fibroblasts, cotransformation was obtained with two plasmids that confer HAT or G418 resistance when integrated into cellular DNA. About 23% of the transformed cells developed both types of resistance. We describe a simple, inexpensive apparatus for carrying out electroporation.

Animals↗

PubMed2026

Single-cell multi-omics dissects transcript isoform and immune repertoire dynamics in human immunosenescence.

Immunosenescence, a major hallmark of systemic aging, refers to the progressive functional decline of the immune system. This decline not only compromises host defense and immunological memory but also fuels chronic inflammation and tissue degeneration (collectively known as inflammaging). While single-cell RNA sequencing (scRNA-seq) has revealed transcriptomic alterations associated with immune aging, analyses restricted to transcript abundance fail to capture deeper regulatory layers, such as transcript isoform diversity and the remodeling of immune receptor repertoires. To address this limitation, we present a human peripheral immune single-cell multi-omics atlas that integrates gene expression, transcript isoform diversity, and immune receptor repertoires. By combining single-cell full-length transcriptome sequencing (scCycloneSEQ), short-read scRNA-seq, and single-cell immune receptor sequencing (scTCR/BCR-seq), we systematically profiled peripheral blood mononuclear cells (PBMCs) from healthy donors aged 30-40 and 60-70 years. Our analyses uncovered extensive age-related remodeling of immune cell composition, functional states, and TCR/BCR diversity. Notably, we found that CD4+ effector memory T cells exhibited widespread differential isoform usage (DIU), 3'UTR length variation, and a marked reshaping of cytotoxic T lymphocyte (CTL) clonotypes-all of which were closely associated with aging-related inflammation and cellular senescence. This multi-omics atlas delineates key molecular features of immunosenescence and provides a high-resolution resource for deciphering the regulatory architecture underlying immune aging.

TCR/BCR↗

PubMed1990

A comparison of the molecular structure of integrated hepatitis B virus genomes in hepatocellular carcinoma cells and hepatocytes derived from the same patient.

To elucidate critical genetic elements in the development of hepatocellular carcinoma associated with hepatitis B virus DNA integration, a single integrant in hepatocellular carcinoma cells and one species of multiple integrants in hepatocytes, both obtained from the same patient, were compared structurally using molecular cloning techniques. Both hepatitis B virus integrants showed similar inverted repeat sequences consisting of two defective virus genomes. The recombination of viral DNAs seemed to be mediated by short regions of base homology near the direct repeat 1 and at other regions of the virus genomes in both integrants. The virus component in the junction with host DNAs was the cohesive end region in each identical end of the viral integrant in hepatocellular carcinoma cells and in one end of the viral integrant in hepatocytes. The structure of the integrant in hepatocellular carcinoma cells was characterized by an inverted, duplicated conformation composed not only of integrated virus genomes but also of flanking cellular sequences. It was shown to be the so-called "alpha dimer" of satellite DNA. In contrast, the flanking, nonreiterated cellular DNA in the hepatocyte-derived clone did not show discernible rearrangement. These findings suggest that a common mechanism underlies the integration of hepatitis B virus DNA so that a similar organization of inverted repeat genomes is found in hepatocellular carcinoma cells and in hepatocytes. The unstable nature of cellular DNA where DNA integration occurs may be important in generating chromosome alterations found in hepatocellular carcinoma.

Adult↗

PubMed1996

Recombinant adeno-associated virus (AAV-CFTR) vectors do not integrate in a site-specific fashion in an immortalized epithelial cell line.

Adeno-associated virus-2 (AAV) can integrate in a site-specific manner to human chromosome 19 and is currently in phase I clinical trials for cystic fibrosis (CF) at Johns Hopkins Hospital. The goal of this study was to determine the fate of recombinant AAV containing the CFTR cDNA (AAV-CFTR) in an immortalized pseudotetraploid CF bronchial epithelial cell line (IB3-1) established from a patient with CF. Fluorescence in situ hybridization (FISH) and Southern blotting of DNA from IB3-1 cells infected with wild-type (wt) or recombinant AAV-CFTR were performed. CFRH2, an IB3-1 cell line with an estimated 15-20 integrated copies of CFTR cDNA, was used to test FISH sensitivity. All metaphase spreads had integrated copies: a single site in 36 of 56 (64.3%) and two sites within the same metaphase spread in 20 of 56 (35.7%). 3-CF-8, an IB3-1 cell line with integration of a partial CFTR cDNA (3.9 kb) was also analyzed by FISH. Integration was observed in 56 of 157 (35.7%) metaphase spreads examined. IB3-1 cells infected with wild-type AAV showed integration in 51 of 86 (59%) metaphase spreads examined. Of 51 integrations, 48 (94%) were to chromosome 19. Examination of 67 metaphase chromosome spreads of IB3-1 cells infected with AAV-CFTR vector (Azero) identified four integrations (6%) to different chromosomes. No integration was to chromosome 19 which differs significantly (P < 0.0001) from wild-type AAV. We then analyzed the A35 cell line, a clone of Azero selected for stable CFTR expression. Genomic DNA from A35 cells did not show a single site of integration; however episomal AAV-CFTR sequences were abundant in the low molecular weight DNA fraction. Examination of 68 metaphase chromosome preparations identified eight distinct integrations, none to chromosome 19. These studies show that FISH is sensitive for the detection of a partial CFTR cDNA integration. Wild-type AAV integrates in a predominantly site-specific fashion. Recombinant AAV-CFTR integrates at low frequency in a nonspecific manner and persists in episomal form in this epithelial cell line.

Bronchi↗

PubMed2003

Protective effect of intracellular ice during freezing?

Injury results during freezing when cells are exposed to increasing concentrations of solutes or by the formation of intracellular ice. Methods to protect cells from the damaging effects of freezing have focused on the addition of cryoprotective chemicals and the determination of optimal cooling rates. Based on other studies of innocuous intracellular ice formation, this study investigates the potential for this ice to protect cells from injury during subsequent slow cooling. V-79W Chinese hamster fibroblasts and Madin-Darby Canine Kidney (MDCK) cells were cultured as single attached cells or confluent monolayers. The incidence of intracellular ice formation (IIF) in the cultures at the start of cooling was pre-determined using one of two different extracellular ice nucleation temperatures (-5 or -10 degrees C). Samples were then cooled at 1 degrees C/min to the experimental temperature (-5 to -40 degrees C) where samples were warmed rapidly and cell survival assessed using membrane integrity and metabolic activity. For single attached cells, the lower ice nucleation temperature, corresponding to increased incidence of IIF, resulted in decreased post-thaw cell recovery. In contrast, confluent monolayers in which IIF has been shown to be innocuous, show higher survival after cooling to temperatures as low as -40 degrees C, supporting the concept that intracellular ice confers cryoprotection by preventing cell dehydration during subsequent slow cooling.

Animals↗

PubMed2004

R5 HIV gp120-mediated cellular contacts induce the death of single CCR5-expressing CD4 T cells by a gp41-dependent mechanism.

The use of CXC chemokine receptor 4 (CXCR4) and CC chemokine receptor 5 (CCR5) by X4 and R5 human immunodeficiency virus (HIV) envelopes (Env) influences HIV cytopathicity. Here, we have evaluated the role of CCR5 and gp41 in Env-induced cell death occurring during the contacts of uninfected, primary cells with MOLT cells infected with different R5 and X4 HIV isolates. As reported for X4-Env, R5 HIV-infected cells destroyed CD4 T cells expressing the appropriate coreceptor by inducing the formation of syncytia and the death of single target cells. Therefore, only the small (<10%) CCR5+ subset of primary CD4 T cells was sensitive to cellular presentation of R5-Env, and CCR5-CD4 T cells showed complete resistance to R5-Env-mediated cell death. X4- and R5-infected cells killed single primary cells by a common mechanism that was dependent on gp41 function and induced a rapid loss of mitochondrial membrane potential and plasma membrane integrity in target cells. Single-cell death was not affected by the blockade of HIV replication in target cells or G-protein signaling through CXCR4/CCR5. In contrast, caspase inhibition (Z-Val-Ala-Asp-fluoromethylketone) profoundly changed the outcome of cell-to-cell contacts by reducing the number of single dead CD4 T cells and increasing the rate of syncytium formation. In conclusion, X4 and R5 HIV Env share a common gp41-dependent mechanism to kill CD4 T cells during cellular contacts. Env tropism and coreceptor expression but not differential killing mechanisms seem to govern the extent of cytopathic effects induced by HIV infection.

CD4-Positive T-Lymphocytes↗

PubMed1995

Fluorescent protein biosensors: measurement of molecular dynamics in living cells.

A new generation of reagents that report on specific molecular events in living cells, called fluorescent protein biosensors, has evolved from in vitro fluorescence spectroscopy and fluorescent analogue cytochemistry. Creative designs of fluorescent protein biosensors to measure the molecular dynamics of macromolecules, metabolites, and ions in single cells emerge from the integrative use of contemporary synthetic organic chemistry, biochemistry, and molecular biology. Future advances in fluorescent probe design, computer-driven optical instrumentation, and software will allow us to engineer endogenous cellular components that localize and function as reporters of their activities, thus moving molecular measurement beyond the single cell to living tissues and the whole organism.

Biosensing Techniques↗

PubMed2002

Three T-cell determinants of Cry j 1 and Cry j 2, the major Japanese cedar pollen antigens, retain their immunogenicity and tolerogenicity in a linked peptide.

It has been demonstrated in detail that administration of a dominant T-cell determinant to animals induces activation or immunological tolerance of T cells. However, it has not been determined whether multiple T-cell determinants, when integrated into a single peptide, retain their potential to induce T-cell activation and tolerance. We prepared a synthetic peptide comprising three T-cell determinants of Cry j 1 and Cry j 2, the major Japanese cedar pollen antigens, and investigated the immunogenicity and tolerogenicity of each T-cell determinant in the linked peptide by means of lymph node cell proliferation assays using mice. Lymph node cells from mice immunized with each of the three T-cell determinants proliferated against the linked peptide in a dose-dependent manner, similar to that of the immunized peptide. Lymph node cells from mice immunized with the linked peptide proliferated against all of the three T-cell determinants. In addition, the degree of proliferation against the three T-cell determinants occurred according to their original immunogenicity, as observed in the native protein antigens. Oral administration of the linked peptide to mice before they were immunized with Cry j 1 and Cry j 2 inhibited lymph node cell proliferation against the three T-cell determinants, depending on the dose of the linked peptide administered. In conclusion, it was demonstrated that three T-cell determinants retain their original immunogenicity and tolerogenicity in a linked peptide comprising them.

Allergens↗

PubMed1985

Patterns of methylation of polyomavirus DNA in polyoma-transformed rat cells.

The patterns of methylation of integrated polyomavirus (Py) DNA and flanking cellular sequences were determined in an inducible line of Py-transformed rat cells, designated LPT, by an analysis of cleavage patterns of LPT DNA generated by the restriction enzymes MspI, HpaII, and HhaI. The Py DNA in LPT cells is integrated into a single chromosomal site and includes whole viral genomes arranged in a head-to-tail configuration. Amplification of the viral DNA and synthesis of infectious virus can be induced in these cells by treatment with carcinogens. The experiments reported here show that in uninduced LPT cells only the late Py genes, which encode the Py capsid proteins, and sequences flanking one of the two viral DNA-cell DNA junctions are methylated. The early genes, encoding the Py T antigens, and sequences flanking the second junction are unmethylated. Since only the early genes are transcribed and translated in uninduced LPT cells, it is apparent that an inverse correlation exists between transcription and methylation of the integrated Py genes in LPT cells, as reported in other cellular and viral systems. The patterns of methylation of integrated Py genomes were also examined in cells of a subclonal derivative of the LPT line in which the virus cannot be activated. In these cells, not only the late Py genes were found to be methylated, but also the 3' portion of the early gene which encodes the Py large T antigen. These findings may have implications for understanding Py induction in LPT cells.

Animals↗

PubMed2026

Spatial Transcriptomics Identifies Characteristic Immunological Niches in Atopic Dermatitis.

BACKGROUND: Atopic dermatitis (AD) is primarily driven by a Type 2 immune response, with T helper (TH2) cells producing IL-4 and IL-13, thereby promoting inflammation, itch, and a compromised skin barrier. Yet, the spatial organization of pathogenic immune cells and their interactions with stromal and epithelial compartments in human AD skin remain incompletely understood. METHODS: We performed 10× Genomics Visium spatial transcriptomics on FFPE skin biopsies from patients with AD (n = 6), psoriasis (n = 2), and healthy controls (n = 5). Data were integrated with AD single-cell RNA sequencing (scRNA-seq) datasets and complemented by imaging mass cytometry (IMC) and multiplex immunofluorescence (IF) to validate the spatial localization of immune cells. Cell-cell communication analysis revealed putative signaling interactions within immune niches. RESULTS: Spatial clustering resolved tissue compartments and demonstrated transcriptional dysregulation in keratinocytes in AD and psoriasis. AD lesions showed a conserved spatial organization of immune aggregates within the superficial dermis. Integration of scRNA-seq signatures revealed spatially organized co-localization of T cells and mature migratory dendritic cells (mmDCs). We developed a ring-based neighborhood analysis to characterize the cellular organization of the immune-stromal niches, revealing T cell-enriched regions surrounded by inflammatory fibroblasts and activated keratinocytes. Intercellular communication analysis further identified putative signaling within mmDC-T cell niches that may promote pathogenic T cell recruitment and activation. Application of tertiary lymphoid structure (TLS) signatures indicated the presence of TLS-like regions. IMC and IF validated the close spatial proximity between activated TH2 cells and mmDCs. CONCLUSION: AD lesions contain spatially organized TLS-like immune niches at the dermal-epidermal junction, characterized by the close association of T cells and mmDCs and coordinated interactions with surrounding stromal and epithelial compartments. These mmDC-T cell niches may represent potential targets for future therapeutic strategies aimed at disrupting persistent local inflammatory pathways and improving long-term disease control.

atopic dermatitis↗

PubMed1982

Acute renal failure--an integrative discussion of morphologic and functional findings.

The ultrastructural alterations at the nephron established in animal experiments, were also confirmed, by means of an electron-microscopic examination, in eight cases of human acute renal failure (ARF). Special consideration was given in this study to single cell alterations, particularly in proximal tubular cells, with emphasis being placed on alterations due to single cell damage in the region of the renal fluid compartments. The ultrastructural alterations of the tubular cells in ARF, suggest serious impairment of the cellular capacity for electrolyte transport and metabolic processes. The shunt paths between the tubular fluid compartment and the functional interstitium, arising from necrosis of the tubular cells or dissolution of the gap or tight junctions, were discussed in terms of their significance for the directional, active transport processes of the tubular cells for sodium chloride and the passive water flow. The morphologic findings were reviewed in light of recent findings on cellular membrane processes and electrolyte transport. A reinterpretation of the morphologic and functional findings in ARF is suggested. This takes into consideration single cell function and the integrity of the renal fluid compartments.

Acute Kidney Injury↗