Cytoplasmic crystals in multiple myeloma-associated Fanconi's syndrome. A morphological study including immunoelectron microscopy

We report a case of Fanconi's syndrome associated with multiple myeloma, which displayed some unusual features. Although serum immunoelectrophoresis showed no spike, urine electrophoresis revealed monoclonal kappa light chain. The myeloma cells in multiple organs including bone marrow, lymph nodes, spleen, and kidneys were distended with characteristic intracytoplasmic crystals. In the kidneys, identical intracytoplasmic crystals were found in some proximal tubules, distal tubules, collecting ducts, glomerular cells (mostly parietal epithelial and endocapillary cells), and renal interstitial cells. Only monoclonal kappa light-chain protein was demonstrated in these crystals by immunofluorescence and immunoperoxidase techniques, a finding confirmed for the first time (to our knowledge) by immunoelectron microscopic study of the renal biopsy specimens.     

Renal and systemic kappa light chain deposits and their plasma cell origin identified by immunoelectron microscopy.

Kappa light chain determinants were identified by immunoelectron microscopy in nodular glomerulosclerotic lesions and systemic interstitial deposits from a man who died several years after the onset of proteinuric renal failure treated by hemodialysis. He developed adrenal and hepatic failure preterminally but not overt malignant myeloma. Specific labeling was most concentrated over the inner aspect of glomerular basement membrane and the mesangium, which suggested that the protein was nonfiltrable. Tubular basement membrane labeling was densest over the outer aspect, which suggested that the protein perfused from the interstitium rather than from the tubular lumen. We identified the source of the protein as a population of plasma cells present within bone marrow and renal interstitium; these showed specific immunogold labeling for kappa light chain protein over organelles concerned with protein synthesis, secretion, and storage. This appears to be the first identification of light chain determinants in human interstitial para-amyloid deposits with the use of immunogold ultrastructural techniques in tissues prepared for electron microscopy by standard methods and stored as epoxy resin blocks.     

Use of immunoelectron microscopy to demonstrate Francisella tularensis.

Three immunoelectron microscopy (IEM) methods were employed to show laboratory-cultivated Francisella tularensis. By the IEM assays, F. tularensis was distinguished from four antigenically distinct gram-negative bacteria. IEM should be a valuable tool for confirming presumptive isolates of F. tularensis and may potentially be useful for demonstrating other medically important bacteria.     

Tamm-Horsfall glycoprotein: ultrastructural immunoperoxidase localization in rat kidney.

Tamm-Horsfall urinary glycoprotein (TH) is the primary constituent of urinary casts. The intracellular distribution of TH in normal rat kidney was determined by immunoelectron microscopy using horseradish peroxidase-labeled antibodies and compared with morphologic localization of TH by immunofluorescence and light immunoperoxidase microscopy. Electron microscopy revealed an intracellular localization of TH restricted to the thick ascending limb of the loop of Henle (ALH). In this nephron segment, TH was distributed on and between adjacent intercellular membranes and infolding intracellular membranes at the base of these cells, within Golgi vacuoles, apical vesicles, and on the luminal membranes. Macula densa cells were negative, although typical ALH cells across the lumen of the same tubular segment were positive. Other renal segments were negative for intracellular TH. The unique distribution of TH is consistent with the known function of the ALH as the diluting segment of the nephron. We speculate that the aggregation and gel formation of TH on and between ALH surface membranes may restrict water movement across the ALH. This influence on permeability would be an important role for TH in the generation of concentration gradients for the countercurrent multiplier system of the kidney.     

Use of immunoelectron microscopy to show Ebola virus during the 1989 United States epizootic.

A filovirus, serologically related to Ebola virus, was detected by "post-embedment" immunoelectron microscopical examination of MA-104 cells. These had been infected by inoculation with serum samples obtained during the 1989 epizootic in cynomolgus monkeys (Macaca fascicularis), imported from the Philippines and maintained at Reston, Virginia, USA, a primate holding facility. The immunoelectron microscopy method, when used in conjunction with standard transmission electron microscopy (TEM) of infected cells, provided consistent results and was simple to perform in this epizootic. It is concluded that immunoelectron microscopy is potentially useful in the direct immunological diagnosis of Ebola and related filoviral infections (such as Marburg) in clinical samples obtained from those with acute infection.     

垂体生长激素细胞腺瘤的电镜及免疫电镜观察

24 cases of growth hormone(GH)-producing pituitary adenomas were studied with electron microscopy and immunoelectron microscopy by protein A-gold complex, 6 cases were identified as densely granulated GH adenoma and 15 cases as sparsely granulated GH adenoma, among which 4 cases were proved by immunoelectron microscopy to be containing granules with prolactin(PRL) activity simultaneously. Intracytoplasmic fibrous bodies were often seen in the sparsely granulated cells anyhow, not all those cells with fibrous bodies possess the secretory granules with GH activity, and fibrous bodies were also detected in some PRL cells of certain mixed type adenoma. This suggests that fibrous bodies might not be the specific morphological feature of pituitary growth hormone cell adenomas.     

Rapid identification of Ebola virus and related filoviruses in fluid specimens using indirect immunoelectron microscopy.

Recent filoviral outbreaks in animal primates have raised public awareness of the potential for filoviruses to become a public health concern; methods that efficiently identify these viruses are therefore of high priority. An indirect immunoelectron microscopy method, which uses homologous guinea pig polyclonal antiserum, successfully identified Ebola-related (Reston) virus particles in serum and tissue culture fluid specimens with infectivity titres of 300 plaque forming units (pfu) per ml or more. The sensitivity of this procedure is sufficient to show virus in most acute phase sera, and is equal to that of the antigen capture enzyme linked immunosorbent assay (ELISA). The immunoelectron microscopy fluid technique can differentiate among antigenically distinct filoviruses in less than three hours. It should be valuable in the rapid diagnosis of potential filoviral infections.     

An immunoelectron microscopic and immunofluorescent study on the antigenic relationship between the coronavirus-like agent,CV 777, and several coronaviruses

Summary A possible antigenic relationship between the porcine enteropathogenic coronavirus-like agent (CVLA) and 6 known coronaviruses was examined by immunoelectron microscopy (IEM) and by immunofluorescence (IF). CVLA did not show cross reactivity with infectious bronchitis virus, transmissible gastroenteritis virus (TGEV), canine coronavirus (CCV) hemagglutinating encephalomyelitis virus (HEV), neonatal calf diarrhea coronavirus (NCDCV) or feline infectious peritonitis virus (FIPV). Antigenic relationship was detected by IEM between TGEV and CCV, NCDCV and HEV and by IF between TGEV and CCV, TGEV and FIPV, HEV and NCDCV.With 2 Figures     

Localization of a murine oncornavirus 15,000-dalton virion protein on the membrane of neoplastic cells: analysis by immunofluorescence and immunoelectron microscopy.

A protein analogous to a 15,000-dalton structural protein of Rauscher murine oncornavirus has been localized on cell membranes of Rauscher erythroblastosis and CC57BR murine lymphosarcoma cells by use of monospecific antiserum in conjunction with immunofluorescence and immunoelectron microscopy techniques. Antigenic determinants of this protein were present on the membranes of erythroblastosis and lymphosarcoma cells, but were absent from the membrane of budding or mature virions. Both typespecific and group-specific determinants of the protein were accessible to antibodies reacting at the cell surface. This viral protein, expressed on the cell membrane, appears to correspond to previously described cell surface antigens of virus-induced murine leukemias.     

Distribution and immunoelectron microscopic localization of laminin, a noncollagenous basement membrane glycoprotein

Laminin is a noncollagenour glycoprotein isolated from a transplantable mouse tumor producting basement membrane (BM). Purified antibodies to laminin do not cross-react with other known BM antigens including type IV collagen, fibronectin, bullous pemphigoid antigen, and a BM proteoglycan. Using immunofluorescence, laminin is localized in the BM zones of those human, chick, guinea pig, bovine, monkey, rat, and mouse tissues examined. Epithelial and endothelial cells in culture synthesize laminin while mesenchymal cells do not. By immunoelectron microscopy, laminin was localized to the lamina lucida of human epidermal BM and of mouse esophagus epithelial BM. The wide distribution of laminin among diverse tissues and species, and in early stages of embryonic development suggests that laminin is an ubiquitous component of basement membranes.     

Detection of HIV envelope specific antibodies by immunoelectron microscopy and correlation with antibody titer and virus neutralizing activity

Human antisera positive for HIV were evaluated on HTLV-IIIB producing cells by two different immunoelectron microscopic (IEM) techniques. In preembedding immunoferritin IEM a heavy label was observed with early budding HIV. Under the same conditions cell released 'mature' particles were almost negative, which could be explained by the direct observation that most of the surface glycoprotein knobs are lost spontaneously during virus maturation. Using freshly infected cultures after agarose embedding, immunogold labelling of ultrathin cryosections allowed us to detect and differentiate internal core as well as virus envelope antigens. A good qualitative correlation between neutralization titers and IEM labelling intensity was observed. This type of immunocryoultramicrotomy appears to be useful for the detection of antigens in and on the virion. It might turn out valuable for the characterization of the env gp120 epitopes of HIV.     

Detection of leptospiral antigen (L. interrogans serovar copenhageni serogroup Icterohaemorrhagiae) by immunoelectron microscopy in the liver and kidney of experimentally infected guinea-pigs.

Guinea-pigs were experimentally infected with L. interrogans serovar copenhageni serogroup Icterohaemorrhagiae and their liver and kidney were studied by immunoelectron microscopy using the post embedding indirect immunogold labelling technique. Primary antibody was a purified rabbit anti-serum produced against the same leptospiral strain used in the inoculum. Gold-labelled leptospiral antigen (LAg) was found close to cell membranes of hepatocytes, kidney tubular cells and endothelial cells of the interstitial capillaries of the kidney. Afterwards it was internalized by hepatic and tubular cells, and eventually found in lysosomes. Phagolysosomes of Kupffer cells were also found to contain remnants of degraded leptospires and gold-labelled LAg. Gold-labelled intact leptospires were detected at the enlarged intercellular spaces between hepatocytes at the areas of hepatic cell plate disarray, showing the potential for leptospiral migration during the septicaemic phase of the disease potentially contributing to the pathogenesis of the lesions. The affinity of leptospiral antigenic material for cell membranes suggests an initial interaction with cell surface proteins followed by its internalization and cell damage. The nature of antigenic material detected, however, remains undefined; it may be a toxin, an enzyme or any other factor/s involved in leptospiral virulence.     

Immunoelectron microscopic identification of human AA-type amyloid: exploration of various monoclonal AA-antibodies, methods of fixation, embedding and of other parameters for the protein-A gold method

Using the postembedding protein-A gold technique ten monoclonal antibodies directed against amyloid-A protein (AA) were examined by immunoelectron microscopy to identify amyloid-A (AA) amyloid fibrils in plastic-embedded renal tissue of five patients and two controls. Two monoclonal antibodies (mc1, mc20) specifically labeled these amyloid deposits; two additional ones (mc4, mc13) bound with an intermediate rabbit anti-mouse IgG antiserum. These monoclonal anti-AA antibodies clearly separate amyloid fibrils from morphologically similar fibrils in the vicinity. Employing varying embedding media, fixation techniques, as well as etching and staining protocols, we adapted this method for the immunoelectron microscopic identification of AA-type amyloid fibrils and for the antigenic diagnosis of AA-type amyloid on routinely processed ultrathin sections.     

Demonstration of amelogenin in the enamel-free cusps of rat molar tooth germs: immunofluorescent and immunoelectron microscopic studies.

The enamel-free cusps of 1-4 day-old rat mandibular first molars were investigated using the monoclonal antibody En3 against rat amelogenin at light and electron microscopic levels in order to clarify whether the enamel-free cusp is virtually devoid of enamel. At 1 day after birth, there were presecretory ameloblast-like cells (PALCs), which were short and were not polarized, at the cusp tips. They were close to the outer enamel epithelium. Hematoxylin positive enamel matrix was not distinctly observed in the enamel-free cusp by light microscopy, but almost continuous immunofluorescence for amelogenin was detected at the interface between PALCs and dentin. The penetration of immunopositive material toward the dental pulp was also observed in the enamel-free cusp. At 4 day after birth, both in the frontal section and in the horizontal section, almost continuous immunofluorescence was recognized at the interface between PALCs and dentin in the enamel-free cusp. The penetration of amelogenin toward the dental pulp was not seen in the enamel-free cusp. By immunoelectron microscopy, immunolabelling was recognized in the Golgi apparatus of PALCs, in a layer of amorphous material at the interface between PALCs and dentin, and in stippled material-like substance in the intercellular space between PALCs. Although no basement membrane was observed beneath PALCs, they did not have Tomes' processes. These investigations suggest that PALCs in the enamel-free cusp differentiate into the secretory cells and that they can synthesize and secrete the amorphous material containing amelogenin at the interface between PALCs and dentin. The penetration of amelogenin toward the dental pulp might play a role in the interaction between PALCs and odontoblasts in the enamel-free cusp and/or the initiation of mineralization of predentin.     

Immunoelectron microscopic detection of tissue ganglioside antigens

Glycolipid antigens are emerging as important markers of differentiated cells in vitro and in vivo. The study of the expression of these antigens in whole tissues by immunoelectron microscopy, using standard techniques, does not give acceptable results. We have established conditions for the specific demonstration of antibody binding to tissue glycolipid antigens by immunoelectron microscopy. Dehydration of tissues with alcohol is to be avoided as it extracts the glycolipid antigen out of the tissue. Dehydration in acetone provides good results. Embedding of the tissue in Araldite 512 results in high non-specific binding of the primary antibody and a decreased effective titre of the primary antibody. Embedding of tissues in Lowicryl HM20 resin resulted in low non-specific binding. We also describe a method of curing the Lowicryl resin that does not require a purpose built curing chamber. Quantitative analysis of immunogold binding reveals that acetone dehydration of tissues and embedding in Lowicryl gives greatly superior results in comparison with dehydration in alcohol and embedding in Araldite.     

Rapid adenovirus typing by immunoelectron microscopy

A rapid method of typing adenoviruses by immunoelectron microscopy is discribed. This emphasizes the value of an electron microscope in diagnostic virology, especially when a rapid result is required in epidemiology.     

Antibody competition studies with gold-labelling immunoelectron microscopy

Competitive studies, involving neutralizing monoclonal antibodies (NTmAbs) to outercoat proteins of Akabane virus were performed by immunoelectron microscopy. The experiments were designed to determine whether the NTmAbs were directed against the same or spatially different epitopes. Characteristics of NTmAbs in direct and indirect gold-labelling studies were determined. It was found that the protein A method gave cross-contamination of the immuno-gold complexes whereas direct conjugation of the NTmAbs to gold probes gave clean, specific and intense labelling. Analysis of dilution curves confirmed that saturation of antigenic sites did not occur and secondly determined the optimum working dilutions for the conjugated probes. The data generated in the preliminary studies enabled reliable results to be obtained from the double-labelling competitive experiment. We found that the 2 NTmAbs were directed to either the same epitope or to 2 separate but neighbouring epitopes where the binding of one NTmAb inhibited the binding of the second. The results demonstrate that if reliable data is to be obtained in double-labelling immunoelectron microscopical studies then experiments must be meticulously designed.     

Protein A-gold immunoelectron microscopic study of amyloid fibrils, granular deposits, and fibrillar luminal aggregates in renal amyloidosis.

Glomeruli of archival renal biopsies, stored frozen at -70 degrees C, from three patients with amyloid were examined by protein A-gold immunoelectron microscopy. In one with both fibrillar and granular deposits from a 'skin popper' drug abuser, the granular deposits were labeled with anti-IgG, while the fibrillar deposits were labeled with anti-amyloid-A (AA) protein and amyloid P component (AP), suggesting coexisting immune complex disease and AA due to different, but possibly related, pathogenesis. In studies using double-label immunostaining of primary amyloidosis-lambda light chain type (AL) and AA associated with Crohn's disease, AP occurred as widely separated single units along the amyloid fibrils and represented 1.5% and 6.5% of the total gold label in AL and AA, respectively, while the major fibril protein was labeled in single rows, similar to beads on a string. Fibrillar aggregates in the capillary lumens were labeled similarly by antisera to the major protein and AP and appeared to be contiguous with the fibrillar deposits at the glomerular basement membrane (GBM)-luminal interface, suggesting intravascular fibrillogenesis.     

Immunoelectron microscopy of cationized bovine serum albumin-induced glomerulonephritis in the rabbit.

Chronic immune complex glomerulonephritis was induced in a group of New Zealand white rabbits by daily intravenous injections of cationized bovine serum albumin (cBSA). The animals were serially killed and renal tissue was embedded in the hydrophilic resin Lowicryl K4M for immunoelectron microscopy. The results demonstrate the progressive deposition of rabbit IgG in the glomerular basement membrane in this model, with aggregation of immunoglobulins occurring only in the subepithelial space. Proteinuria developed concurrently with this event. Glomerular visceral epithelial cell (GVEC) endocytosis of immune material was observed at various stages of the disease process, suggesting that GVECs may be part of a clearance mechanism acting within the glomerulus.     

Radio frequency glow discharge and solid-phase lactoperoxidase-glucose oxidase beads as methods for etching ultra-thin plastic sections for immunoelectron microscopy

Etching techniques to prepare ultra-thin sections for immunoelectron microscopy have incorporated a variety of reagents to expose antigenic sites. In this paper involving 2 techniques for surface etching prior to immunoelectron microscopy, radio frequency glow discharge ( RFGD ) and solid-phase lactoperoxidase-glucose oxidase beads ( Enzymobeads ) are compared to conventional peroxide etching techniques. Measuring such parameters as intensity of granule disposition and titers of antibody resulting in detectable staining. RFGD and Enzymobeads were both superior to the conventional peroxide methodology. Non-specific absorption by ferritin under the conditions utilized was not a problem with Enzymobeads or RFGD method. In addition, RFGD may be useful in situations where peroxide susceptible antigens are under study.