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PubMed1993

Detection by scanning electron microscopy of a distinctive esophageal surface cell at the junction of squamous and Barrett's epithelium.

Metaplastic columnar epithelium replaces the normal squamous epithelium in Barrett's esophagus. We characterized the surface epithelial cells of the junction between squamous and Barrett's epithelium using scanning electron microscopy and light microscopy. In four biopsy specimens from the squamous-Barrett's junction in three patients, we found a distinctive cell type having features intermediate between those of squamous and columnar epithelium. Its distinguishing characteristic is the presence on its surface of two disparate structures not normally present on the same cell in the gastrointestinal tract: microvilli (a scanning electron microscopy feature of glandular epithelium) and intercellular ridges (a scanning electron microscopy feature of squamous mucosa). The surface characteristics of this newly recognized cell were strikingly similar to those of cells found in the transformation zone of the uterine cervix, an area in which squamous epithelium physiologically replaces columnar epithelium. We also examined 28 biopsies of the gastroesophageal junction area from 14 patients with and without a history of heartburn but with no evidence of Barrett's esophagus. None of these biopsies showed the distinctive cell. We hypothesize that this distinctive cell represents an intermediate step in either the development or the healing of Barrett's epithelium, during which surface characteristics of two different cell types, columnar and squamous, coexist on the same cell.

Aged↗
PubMed1995

DNA localization in nuclear fragments of apoptotic ameloblasts using anti-DNA immunoelectron microscopy: programmed cell death of ameloblasts.

Ameloblasts responsible for tooth enamel formation are classified into two different phases: secretion and maturation. At the transition between these secretion and maturation stages, a considerable number of cells die. In this study, we examined the morphology of degenerating ameloblasts by conventional electron microscopy, and DNA cleavage in degenerating ameloblast nuclei by the in situ terminal transferase assay. The results suggest that apoptosis (programmed cell death) in ameloblasts, including DNA ligation is induced at the transitional stage. The nuclear fragments, chromatin condensation and DNA relocation in apoptotic nuclei were examined quantitatively by post-embedding anti-DNA immunogold electron microscopy and the in situ terminal transferase assay combined with electron microscopy. Numerical analysis revealed that immunogold labeling density in the condensed chromatin of apoptotic nuclei was comparable on the average to that in the perinuclear heterochromatin of normal nuclei, and that individual apoptotic nuclear fragments exhibited highly variable to that of normal heterochromatin, to fragments with densities twice as high as that of normal heterochromatin. The in situ terminal transferase assay combined with electron microscopy detected DNA ends exposed by ultrathin sectioning as well as DNA cleavage by a putative endonuclease. In conclusion, the state of the DNA, including its ligation and degeneration, changes gradually during chromatin condensation and nuclear fragmentation of apoptosis.

Ameloblasts↗
PubMed1979

Normal and pseudorabies virus infected primary nerve cell cultures in scanning electron microscopy.

Primary cell cultures from the central nervous system of the embryonic rat were inoculated with pseudorabies virus. Their morphological changes were studied by phase contrast microscopy and by scanning as well as by transmission electron microscopy. Uninfected cultures display two distinct cell layers in scanning electron microscopy: a flat continuous monolayer supports a heterogeneous population of individual, presumably neural cells, which emit processes of different number and size. The latter cells form contacts by a dense network of fibres. Infectious virus is propagated in these nerve cell cultures with similar effectivity as in other cultures. The infectoin leads to fusion and death of the cells. By the time the cytopathic effect is visible, nearly all cells, including those of neuronal and those of nonneuronal appearance, are studded with ample amounts of virus-sized particles. The particles represent viruses as demonstrated by transmission electron microscopy or by treatment with a hyperimmune serum directed against pseudorabies virus structural components. Hyperimmune serum leads to clustering of the particles at the cell surface. The amount of virus particles per surface unit was about 10 times higher on neural cells as compared to primary rabbit kidney cells. The concentration of infectious particles in the supernatant, however was approximately the same. The system described appears to be useful for the study of acute virus effects on neural tissue under strictly controlled conditions.

Animals↗
PubMedDate not supplied

Image enhancement of the in vivo leukocyte-endothelium contact zone using optical sectioning microscopy.

A major determinant of the strength of leukocyte [white blood cell (WBC)] to endothelium [endothelial cell (EC)] adhesion is the contact area formed between the two cells, which is often obscured by out-of-focus information inherent to intravital microscopy. To improve visualization of the WBC-EC contact zone, techniques of optical sectioning microscopy were developed to enhance brightfield images of WBC-EC adhesion in postcapillary venules of the mesentery of the rat. A 50x/1.0 NA objective was held in a piezoelectric mount that was computer-driven, and video images were obtained by digitizing images from a CCD camera while focusing through the vertical direction in 1 micron steps over a depth of 16 microns. Using measurements of the microscope's optical transfer function, deconvolution of the central image was performed in the Fourier domain using the technique of singular value decomposition with Tikhonov-Miller regulation to remove out-of-focus information. Measurement of the length of the WBC-EC contact zone (LC) in the original images yielded values on the order of 4.32 +/- 1.08 microns (mean +/- SD). The enhanced images showed a significantly 35% smaller LC equal to 2.78 +/- 0.70 micron. Topical application of the chemoattractant f-met-leu-phe resulted in a 26% increase in LC to 3.49 +/- 0.72 micron, thus suggesting that upregulation of adhesion molecules on the WBC membrane results in the recruitment of additional membrane area from surface ruffles into the zone of adhesion. Other advantages of the deconvolution were to visualize structural characteristics of the microvascular wall and parenchymal tissue in greater detail. Thus, brightfield optical sectioning microscopy may provide a valuable tool for in vivo studies of the microvasculature, and serves as a useful alternative to fluorescence microscopy without the undesirable effects of exogenous fluorophores and exposure to ultraviolet radiation.

Algorithms↗
PubMed1975

Scanning electron microscopy of the nephrotic kidney.

Scanning electron microscopy (SEMy), supplemented with light microscopy and transmission electron microscopy, was used to study aminonucleoside nephrosis in rats. The visceral epithelium undergoes dramatic restructing in response to aminonucleoside nephrosis. Due in part to an accumulation of intracellular vacuoles, kidney podocytes swell in size. Podocyte major processes lose their many pedicles and slit pores and form close junctions (80 A) with adjacent podocytes. Although no prominant pores opening into the urinary space are found in the visceral epithelium, there is evidence that podocyte vacuoles may rupture and thereby release protein into the urinary space. Many parietal cells also increase in size, accumulate intracellular vacuoles and come into very cose proximity to the visceral epithelium. Casts of PAS-positive, electron-dense material fill the lumina of many uriniferous tubules. Although most proximal tubules exhibit an extensive loss of brush border, no significant changes in other kidney microprojections or cilia were noted. Transmission electron and light microscopy of nephrotic kidneys reveal considerable changes in proximal and distal tubules including a reduction in mitochondria, in cell height, in electron density of the cytoplasmic matrix, in lateral and basal plasmalemma infolds, enlarged euchromatic nuclei, dilated lumens, and accumulation of PAS-positive cytoplasmic granules. SEMy of kidney needle biopsies from patients with proteinuria reveal that SEMy is useful for evaluating glomerular changes in man.

Animals↗
PubMed2006

Fourier transform infrared imaging and MR microscopy studies detect compositional and structural changes in cartilage in a rabbit model of osteoarthritis.

Assessment of subtle changes in proteoglycan (PG) and collagen, the primary macromolecular components of cartilage, which is critical for diagnosis of the early stages of osteoarthritis (OA), has so far remained a challenge. In this study we induced osteoarthritic cartilage changes in a rabbit model by ligament transection and medial meniscectomy and monitored disease progression by infrared fiber optic probe (IFOP) spectroscopy, Fourier transform infrared imaging spectroscopy (FT-IRIS), and magnetic resonance imaging (MRI) microscopy. IFOP studies combined with chemometric partial least-squares analysis enabled us to monitor progressive cartilage surface changes from two to twelve weeks post-surgery. FT-IRIS studies of histological sections of femoral condyle cartilage revealed that compared with control cartilage the OA cartilage had significantly reduced PG content 2 and 4 weeks post-surgery, collagen fibril orientation changes 2 and 4 weeks post-surgery, and changes in collagen integrity 2 and 10 weeks post-surgery, but no significant changes in collagen content at any time. MR microscopy studies revealed reduced fixed charge density (FCD), indicative of reduced PG content, in the OA cartilage, compared with controls, 4 weeks post-surgery. A non-significant trend toward higher apparent MT exchange rate, k(m), was also found in the OA cartilage at this time point, suggesting changes in collagen structural features. These two MR findings for FCD and k(m) parallel the FT-IRIS findings of reduced PG content and altered collagen integrity, respectively. MR microscopy studies of the cartilage at the 12-week time point also found a trend toward longer T (2) values and reduced anisotropy in the deep zone of the OA cartilage, consistent with increased hydration and less ordered collagen. These studies reveal that FT-IRIS and MR microscopy provide complementary data on compositional changes in articular cartilage in the early stages of osteoarthritic degradation.

Animals↗
PubMed2001

Recognition of basic fuchsin prestained microfissures of intravital origin with fluorescence microscopy: validation of a shortcut.

For 70 years it has been suspected that not all microfissures in histological bone sections are artifacts, but that some are provoked in vivo through repetitive stress. The development of undecalcified bone techniques and of the bulk staining technique has established a method for demonstrating the existence of intravital cracks and enhanced the discrimination towards artifactual microfissures in the load-bearing skeleton. Recently the presence of intravital microfissures has also been ascertained in temporal bones by these techniques. Due to the fluorescent properties of basic fuchsin it is possible to use epifluorescence microscopy for analysis of microfissures after bulk staining with basic fuchsin. This provides a more steady microscopic background and a sharper delineation of surface level structures since no projection from lower levels interfere. Artifactual cracks, which in transmitted light microscopy may look like darkly stained intravital microfissures due to refraction phenomena, become invisible or colorless. Epifluorescence microscopy enhances the detection of both smaller and larger prestained intravital microfissures, and leaves only a minor part of the cracks without certain categorization. The epifluorescence mode of analysis has the further advantage of being independent of slice thickness, making feasible whole-specimen analysis by serial stepwise grinding. The present study shows that the number and the length of microfissures in the human otic capsule, counted and measured under the epifluorescence microscope, equals numerically the findings in light microscopy, enabling the routine use of this mode of analysis. This may prove to be of particular value in the research into the etiology and pathogenesis of otosclerosis as well as perilymphatic fistulae.

Adult↗
PubMed1999

Confocal microscopy in lattice corneal dystrophy.

BACKGROUND: The purpose of the study was to assess the appearance of lattice corneal dystrophy by means of white-light confocal microscopy. METHODS: Two consecutive patients with lattice corneal dystrophy were prospectively examined. In vivo white-light tandem-scanning confocal microscopy was performed in the right eye of the first patient. Her left eye had undergone penetrating keratoplasty 4 years earlier. Histologic findings of the corneal button were compared with confocal microscopic findings of the right eye. The other patient was monocular and confocal microscopy was performed only in the non-seeing eye. RESULTS: In both patients, linear and branching structures with changing reflectivity and poorly demarcated margins were visualized in the stroma. The linear structures measured approximately 40-80 microm in width. CONCLUSION: Lattice corneal dystrophy presents characteristic linear images on confocal microscopy and should not be misdiagnosed as fungal hyphae in cases of corneal infection.

Aged↗
PubMed1982

Light and electron microscopy of liver in hyperlipoproteinemic patients under long-term gemfibrozil treatment.

The effects of long-term gemfibrozil (Lopid) therapy on human liver structure are not known. Studies of this nature are becoming essential in determining the risk/benefit ratio since gemfibrozil is an effective agent for the control of hyperlipoproteinemia types IIa, IIb, and IV. Particularly, gemfibrozil is effective when dietary management or available therapeutic control fail to reduce serum cholesterol and triglycerides as well as normalizing the lipoprotein pattern. Percutaneous liver biopsies of 9 patients on long-term gemfibrozil therapy were evaluated by light microscopy, interference contrast optics and transmission electron microscopy. The distribution of patients according to lipoprotein phenotype was 3 Type IIa, 3 Type IIb, and 3 Type IV. Their lipoprotein patterns approached normal and the serum lipids were controlled during gemfibrozil therapy. By light microscopy, the lobular architecture and other parameters were within normal limits. Varying degrees of fatty change were found as would be expected. No preferential lobular disposition of the fat globules was evident. Coalescence of fat droplets, nuclear displacement and fatty cysts were noted. Differential interference contrast microscopy revealed several degrees of contrast amplitude in these droplets suggesting a heterogeneous lipid deposition in hepatocytes. The subcellular analysis revealed a moderate degree of glycogen deposition, absence of nuclear abnormalities and unremarkable mitochondria; the rough endoplasmic reticulum was not significantly altered and smooth surfaced membranes appeared proliferated. Detailed analysis of the peroxisome population showed matrix rarefaction, marginal plate formation and spurious densities though no significant proliferation occurred. Distribution of peroxisomes in hepatocytes varied widely from cell to cell and in different lobular areas. This study confirmed the association of hepatic fatty change with hyperlipoproteinemia irrespective of the pattern observed in circulating lipoproteins. Peroxisome proliferation, as seen in rodents when receiving gemfibrozil, did not occur and the structure of these subcellular organelles was not compromised. It was concluded that the long-term administration of this compound did not show adverse effects on the hepatocyte in hyperlipoproteinemia.

Gemfibrozil↗
PubMed1994

Imaging neuronal development with magnetic resonance imaging (NMR) microscopy.

An ideal technique for following the development of the vertebrate nervous system would allow cells to be followed at the resolution of light microscopy at depths of several millimeters into the tissue. This would permit critical events to be followed at cellular or sub-cellular resolution even deep within the developing organism. To date, no technique has emerged with all of the needed properties. Light microscopy can follow a cell and its descendants after they have been labeled by either the infection of embryonic cells with a recombinant retrovirus or the microinjection of individual precursor cells with enzymes or fluorescent dyes. However, light microscopy cannot image events deeper than a few hundred micrometers within an embryo due to light scattering and aberrations in the objective lenses and other optics. Magnetic resonance imaging (MRI) does not suffer from these limitations, routinely being used to image in 3 dimensions through specimens as large as adult humans. However, it is relatively slow and, as implemented to date, it cannot routinely achieve cellular resolution. Here, we present our attempts to meet the technical challenges posed by in vivo MRI microscopy. As an example of both the progress and the future challenges, we present images of cells within the developing frog embryo over a several day time course.

Animals↗
PubMed1983

Comparison of analysis of bovine surface immunoglobulin bearing and peanut agglutinin binding lymphocytes by flow cytometry and fluorescence microscopy.

Bovine peripheral blood lymphocytes were examined for their binding to anti-immunoglobulin serum, peanut agglutinin, and mu, alpha, and epsilon heavy chain specific antisera by immunofluorescence. The percentage of total lymphocytes with positive staining was determined independently by flow cytometry and fluorescence microscopy. The correlation of data from both methods was best for analysis of total surface immunoglobulin and IgM bearing cells. The percentage of lymphocytes bearing surface immunoglobulin (B cells) was determined using both whole antiserum and a F(ab')2 reagent. Quantitation by flow cytometry did not show a significant difference when the two reagents were used, whereas fluorescence microscopy revealed a significant difference (p less than .05). The mean percent of total surface immunoglobulin bearing cells was 30 +/- 3% by either method. Flow cytometry gave significantly larger values than fluorescence microscopy for samples stained with fluorescein conjugated peanut agglutinin. Peanut agglutinin binding cells comprised 70 +/- 3% by flow cytometry and 51 +/- 3% by fluorescence microscopy. Similarly, there was a significant difference between both methods when IgA bearing lymphocytes were examined. Percentages of immunoglobulin E, A, and M bearing lymphocytes as well as total B and T cells in spleen and bronchial lymph node were determined by immunofluorescence using the cytofluorograph. Peanut agglutinin binding cells were less numerous in spleen and lymph node than in peripheral blood. Immunoglobulin E bearing lymphocytes increased from 0.07% in peripheral blood to 4% in spleen and 1.9% in lymph node. In this paper we demonstrate how flow cytometry can be used to examine a large number of samples in a rapid and reproducible manner. This is the first report in which bovine lymphocytes bearing surface IgE are quantitated.

Animals↗
PubMed1981

Comparison of immunosorbent electron microscopy, enzyme immunoassay and counterimmunoelectrophoresis for detection of human rotavirus in stools.

The detection of human rotaviruses by routine electron microscopy examination of stool specimens has been compared with the sensitivity of detection obtainable by three different immunoassays. These assays are: 1) immunosorbent electron microscopy (ISEM), which consists of the serological trapping of viruses on electron microscopy grids coated with protein A and specific viral antiserum; 2) an enzyme-linked immunosorbent assay (ELISA), in which the primary antibody is rabbit anti-rotavirus immunoglobulin, the secondary antibody is chicken anti-rotavirus immunoglobulin extracted from egg yolk of immunized hens, and the indicator antibody is alkaline phosphatase-conjugated rabbit anti-chicken immunoglobulin; 3) counterimmunoelectrophoresis (CIE). A total of 63 stool specimens from infants with gastroenteritis were examined. Of these, 23 and 24 specimens were found to contain rotavirus by electron microscopy and CIE, respectively. When scored by ELISA and ISEM, 37 and 39 were found to be positive, respectively. Confirmatory inhibition assays were necessary to eliminate some false positive reactions in ELISA. Detection of human rotaviruses in stools by ISEM is as sensitive as by ELISA, but in weakly positive specimens, ISEM offers the additional advantage of a direct visual demonstration of the presence of the aetiological agent.

Antigens, Viral↗
PubMed1991

Detection of Norwalk-like virus and specific antibody by immune-electron microscopy with colloidal gold immune complexes.

Direct electron-microscopy (DEM), immune electron microscopy (IEM) and four different procedures of immune electron microscopy with colloidal gold immune complexes were evaluated for the detection of Norwalk-like virus and specific antibody. A solid-phase immune electron microscopy with colloidal gold immune complexes-triple layer method (SPIEMGIC-TLM) is developed for screening patients' specimens for the detection of Norwalk-like virus and its specific antibody. The method demonstrates low non-specific background labelling and is simple, sensitive and easy to perform. A quadruple layer method (SPIEMGIC-QLM), which is a modification of the triple layer method, has been established by adding a cross-linking anti-IgG layer to amplify the reaction and to provide a more sensitive test which is suitable for screening monoclonal antibodies prepared against 32-34-nm Norwalk-like virus isolated in our laboratory.

Antibodies, Monoclonal↗
PubMed1991

Magnetic resonance microscopy of toxic renal injury induced by bromoethylamine in rats.

The alkylhalide 2-bromoethylamine hydrobromide (BEA) produces renal injury in rats that mimics analgesic-related renal injury in humans. Our purpose was to examine this injury, in vivo in rats, with magnetic resonance (MR) microscopy and correlate MR findings with findings from light microscopy of hematoxylin-eosin-stained sections. Rats (n = 48) were injected intravenously with BEA (150 mg/kg) or saline and imaged with MR 6, 48, and 336 hr later. The spin-spin relaxation time, T2, was measured from the cortex to the papilla. In other rats, we measured regional water content of the kidney. Renal injury was present 48 and 336 hr after BEA dosing based on increased renal organ weights, decreased urine specific gravity, and significant renal lesions (H & E). T2 was elevated in the inner stripe of the outer medulla in injured kidneys at 48 hr. The differences in T2 between cortex and outer medulla were also elevated 48 hr after BEA. In the inner medulla, there were no changes in T2 after BEA treatment. However, in all groups there were significant regional differences in T2. The value of T2 increased from outer to inner medulla and this gradient was directly correlated with water content. Thus, MR microscopy detected damage in the outer medulla after BEA injury but not the damage in the inner medulla. T2 appeared to reflect the water content in the different regions of the medulla. The noninvasive in vivo capability of MR microscopy, with its high sensitivity to tissue water, allows the toxicologist to monitor the progression and regression of toxic insult in the same animal. At present the technology is complicated. The precise and accurate measure of MR-sensitive parameters in live animals at microscopic resolution is difficult. However, as the technology matures, there will be significant improvements providing the toxicologist a unique in vivo tool.

Animals↗
PubMed1985

The use of lectin transport in the mouse central nervous system as an anterograde axonal marker for electron microscopy.

Lesion-induced axonal degeneration and autoradiography-electron microscopy have been the only reliable anterograde axonal markers available for electron microscopic examination of neuronal circuitry. However, these methods have their limitations. Recently, Phaseolus vulgaris-leucoagglutinin (PHA-L) has been used as an anterograde axonal marker for light microscopy. This report describes the use of this lectin as an anterograde marker for electron microscopy. PHA-L was injected into mouse SmI cortex or ventrobasal thalamus. Using standard immunohistochemical techniques, the transported lectin was tagged with antibody, which was then visualized with avidin-biotin-horseradish peroxidase binding. Light microscopy demonstrated anterograde transport to predicted cortical regions. With the electron microscope, labeled axon terminals were seen forming asymmetric synapses with spines, dendrites and cell bodies.

Afferent Pathways↗
PubMed1987

Incorporation of vesicular antigens into the presynaptic membrane during exocytosis at the frog neuromuscular junction: a light and electron microscopy immunochemical study.

We have studied the incorporation of vesicular membrane antigens into the presynaptic membrane during exocytosis of neurotransmitter at the frog neuromuscular junction. In a preliminary series of experiments, we first confirmed by electron microscopy that the synaptic vesicles are labelled following incubation with rabbit antisynaptic vesicle antibody of neuromuscular junction cross sections (cytoplasm and organelles reached by the antibodies). In a second series of experiments, intact neuromuscular junctions were stimulated with black widow spider venom and fixed with paraformaldehyde. The presence or absence of vesicular antigens in the presynaptic membrane was monitored with rabbit antisynaptic vesicle antibody and revealed with a second antibody coupled to peroxidase. In light microscopy, the labelled neuromuscular junctions are almost completely restricted to muscles stimulated with black widow spider venom and incubated with rabbit antisynaptic vesicle antibody. Only a few control muscles (not stimulated with black widow spider venom, but incubated with rabbit antisynaptic vesicle antibody) had labelled neuromuscular junctions. All control neuromuscular junctions, not incubated with rabbit antisynaptic vesicle antibody were unlabelled. Electron microscopy indicated that it is the presynaptic membrane of intact stimulated neuromuscular junctions which is labelled. In these intact neuromuscular junctions, the synaptic vesicles are usually unlabelled. Electron microscopy also indicated that the presynaptic membrane of only one type of control junctions (not stimulated with black widow spider venom, but incubated with rabbit antisynaptic vesicle antibody) is rarely and weakly labelled. Other types of controls (not incubated with rabbit antisynaptic vesicle antibody) are never labelled. Therefore our results are consistent with the incorporation of vesicular antigens into the plasma membrane during exocytosis produced by the black widow spider venom. The low level of labelling of unstimulated neuromuscular junctions suggest a rather complete retrieval of the vesicular proteins during endocytosis.

Animals↗
PubMed2004

Polarisation microscopy increases the sensitivity of hemozoin and Plasmodium detection in the histological assessment of placental malaria.

The histological study of the placenta is useful in the diagnosis of malaria during pregnancy. However, the scarcity of parasites and pigment in many malarial infections renders their identification difficult. We have tested the accuracy of standard and polarisation microscopy in the evaluation of 500 placental specimens from an area of high malarial endemicity in Tanzania. Standard microscopy showed a low sensitivity (50.3% for parasites, 40.5% for pigment), due to poor detection rates in cases with scant parasites (12.7% for <1%; 97.8% for >5% parasitised erythrocytes, P < 0.001 ) or minimal pigment deposition (42.4% versus 84.5% when severe, P < 0.001 ). The use of polarisation microscopy significantly increased the sensitivity of detection of pigment to 100% and parasites to 98.1% because of the marked birefringence of hemozoin present in mature stage parasites which accumulate in the placenta. Formalin pigment shares many properties with hemozoin, but the use of neutral buffered formalin prevented the formation of formalin pigment in placentas even after long periods of fixation. In conclusion, polarisation microscopy is a simple tool that markedly increases the sensitivity of the detection of malaria infection in the placenta and has good specificity when used on tissues fixed in neutral formalin. This method can be useful to investigators working in the malaria field.

Animals↗
PubMed2004

Quantification of cell hybridoma yields with confocal microscopy and flow cytometry.

The fusion of antigen presenting and cancer cells leads to the formation of hybrid cells, which are considered a potential vaccine for treating cancer. The quality assessment of hybrid cell vaccines is crucial for the introduction of this new treatment. Flow cytometry was the method used recently, since it is faster in comparison to classical microscopy. Here we describe a rapid confocal microscopy based approach to quantify hybrid cell yields. The extent of fusion rate was determined by confocal microscopy by counting dual fluorescent cells and by measuring the area of co-localized pixels. Results of both methods showed high degree of correlation. The same samples were also analyzed by flow cytometry. Fusion rates determined with both techniques showed significant correlation. In conclusion, using confocal microscopy we developed a sensitive and a rapid method to assess the yield of hybridomas in a large number of electrofused cells.

Animals↗