Altered phospholipids in human rheumatoid synoviocytes

A specific cytochemical reaction for freely available phospholipids has shown a raised concentration of such phospholipids in the lining cells of human synovial membranes removed from rheumatoid joints. Quantitative measurement, by microdensitometry, of the amount of reaction-product per cell showed that the rheumatoid synoviocytes contained almost three times the amount of free phospholipids present in the equivalent nonrheumatoid cells; statistically the difference was highly significant. Evidence from studies in which the bound phospholipids were 'unmasked' by methanol-chloroform confirmed the view that the increased content of freely available phospholipids was related to altered lipid-protein binding rather than to an increase in total phospholipids.

Arthropathy as the major clinical indicator of occult iron storage disease

Chronic arthritis was the only symptom that led to the detection of increased iron stores in four patients. In these persons, the serum iron was ordered at the time of initial examination, and ranged from 212 to 237 microgram/dl with a transferrin saturation of 83% to 100%. Liver biopsy specimens showed hepatocyte iron deposition in each person, with definite cirrhosis in only one patient. These cases illustrate that a chronic arthropathy may be the first clinical manifestation of iron overload, and can lead to discovery of the disease in patients and their family members. Treatment may then be initiated before extensive tissue damage has occurred.

Polymeric debris in synovium after total joint replacement: histogical identification

In studying a series of synovial biopsy specimens from patients with loose joint replacements, we were able to differentiate reliably between polymethylmethacrylate and ultra high-molecular-weight polyethylene by observing alterations in their birefringence with changes in temperature. The glass transition temperature of polymethylmethacrylate (when it softens from a glass-like to a rubber-like state) is about 105 degrees centigrade. Polyethylene melts at 135 degrees centigrade. The birefringence in polyethylene returns after it has been melted and then cooled; this is not true of methylmethacrylate fragments heated above their glass transition temperature. When cooled, methacrylate fails to regain its birefringence. In addition, free particles of the two plastics were studied in vitro to validate this method of differentiation. We recommend its use routinely in histological studies of patients with loosening.

Localization of gold in synovial membrane of rheumatoid arthritis treated with sodium aurothiomalate. Studies by electron microscope and electron probe x-ray microanalysis

The localization of gold in the synovial membrane of rheumatoid arthritis patients treated with sodium aurothiomalate was examined and quantitative analysis of epon-embedded sections was carried out with a wavelength dispersive x-ray microanalyser. Gold was only detected in the lysosomes of synovial lining type A cells and subsynovial mononuclear cells in the form of filamentous deposits and highly electron-dense granules, the latter being few in number. The concentration of gold within the lysosomes containing the characteristic deposits and granules was equivalent to that in epon-embedded standard specimens of freeze-dried albumin in which 2-0-87-4 mg/ml of gold was included. In addition, sulphur was detected in the lysosomes containing the filamentous deposits, but the S/Au x-ray signal ratio was not equal to that detected in sodium aurothiomalate. The significance of the coexistence of gold with sulphur in lysosomes is discussed.

Chalky joint effusion. The result of massive synovial deposition of calcium apatite in progressive systemic sclerosis

A patient with long-standing progressive systemic sclerosis developed calcification of the suprapatellar pouch. Chalky white synovial fluid from the knee joint contained many crystals that were characterized as apatite by X-ray diffraction. In this case massive amounts of cystals were presumably shed into the fluid from the heavily calcified synovium.

Immunohistochemical localization of prostaglandin E in rheumatoid synovial tissues

Synovial tissues removed at synovectomy from patients with active rheumatoid arthritis (RA) or osteoarthritis (OA) were examined for prostaglandin E (PGE) by immunohistochemical techniques using rabbit antisera specific for PGE. Marked increments of PGE were noted in RA synovia in comparison to OA, with staining concentrated in synovial lining cells, interstitial inflammatory cells, and endothelial cells of blood vessels. A correlation was noted between the degree of synovial lymphocytic infiltrate and the intensity of PGE staining. These studies provide initial cellular localization of PGE in such tissues.

Synovial deposit of osmic acid after intra-articular injection. Anatomical and radiologic study of a case

An anatomical and radiologic study of a synovial autopsy specimen 32 months after an intra-articular injection of osmic acid for the local treatment of a rheumatoid synovitis. Osmium deposits are seen within peripheral cells of a fat lobule and also in a few histiocytes of the scar tissue which replaced the rheumatoid synovitis. These osmium deposits in the fat cells are present in a sufficient quantity to give a radiologic opacity.

Ultrastructure of the haemophilic synovial membrane and electron-probe X-ray analysis of haemosiderin

An ultrastructural study of the haemophilic synovial membrane revealed the presence of solitary siderosomes, compound siderosomes and a peppering of the cell cytoplasm with electron-dense particles. These changes were found in synovial intimal cells, subsynovial macrophages and fibroblasts. Electron-probe X-ray analysis of siderosomes revealed the presence of iron and traces of phosphorus. On the basis of previous and present studies it is postulated that haemosiderin is essentially a condensate of hydrated ferric oxide and that a variable amount of phospholipid material lies in company with it in the siderosome.

Electron probe x-ray analysis of siderosomes in the rabbit haemarthrotic synovial membrane

Electron probe x-ray analysis of siderosomes produced in the rabbit synovial membrane by repeated injections of autologous blood revealed two kinds of siderosomes; (1) those containing a small amount of phosphorus and, (2) those in which no phosphorus was detectable. On the basis of these findings and past studies it is concluded that haemosiderin is an inorganic compound of iron, probably a hydrated ferric oxide and that a variable amount of organic material (proteins, lipids, phospholipids, etc.,) probably occurs in company with the haemosiderin in the siderosome, but these variable components which decrease in amount with the passage of time cannot be considered as an integral part of haemosiderin.

[Further observations on the presence of iron in the articuler synovial membrane]

In 1971, a study of 66 synovial biopsy samples indicated that the presence of ferric deposits in the subintimal synovial tissue was of real semiological value in the diagnosis of rheumatoid synovitis. In 1975, a study of 228 synovial biopsy samples led the authors to reconsider this finding: the presence of ferric deposits in the subintimal synovial tissue was far from being a constant feature in rheumatoid synovitis and it was seen with similar frequency in other forms of chronic inflammatory rheumatism and also in several other joint conditions. The origin of the synovial iron and the influence it may have on the development of the rheumatoid processes remain obscure.

[Study of glycoprotein extracted from synovial membranes of oxen]

Authors describe a glycoprotein that they have extracted from synovial membrane of oxen. From a total extract CTC, the fraction is purified by precipitation with ethanol then by filtration on biogel. The composition and some physicochemical and immunogical characters are described.

Electron microscopic autoradiography of 35SO4-labelled material closely associated with collagen fibrils in mammalian synovium and ear cartilage

Electron microscopic autoradiography of connective tissue obtained from mice and rabbits previously injected with 35SO4 indicated that sulphated proteoglycans are localized on collagen fibrils. Ruthenium Red-positive transverse belts surrounding fibrils near the a-bands were heavily labelled, but fine lateral filaments of Ruthenium Red-positive material were not. These filaments, which interconnect collagen fibrils in a variety of connective tissues may represent linear aggregations of hyaluronic acid, glycoproteins and non-sulphated or long-lived sulphated proteoglycans.

Evolution of aurosomes in rabbit synovial membrane

Intra-articular injection of sodium aurothiomalate (Myochrysine) into rabbit knee joints produced lysomes (aurosomes) of a characteristic morphology in synovial intimal cells and subsynovial macrophages. Such lysosomes are distinct and different from other lysosomes and those seen after injection of sodium thiomalate. A study of the morphological events that occur after injection of gold salt shows that at first the aurosome contains electrondense granules but later membranous formations (myelinoid membranes) presenting as rod-like and curled structures develop. With electron probe x-ray analysis, gold, phosphorus, and traces of calcium were detected in the aurosome.

Ultrastructural changes produced in rheumatoid synovial membrane by chrysotherapy

Biopsies of rheumatoid synovial membrane before and after chrysotherapy were examined with the light and electron microscopes, and subjected to electronprobe x-ray analysis. The main change noted was the occurrence of electron-dense deposits of characteristic morphology within pre-existing lysosomes. Such deposits were also seen in other varieties of lysosomal bodies. X-ray analysis showed the presence of gold, phosphorus, osmium, and calcium in these deposits. The present study shows that gold enters the pre-existing lysosomes, supporting the concept that the beneficial effects of chrysotherapy are due to its action on the lysosome.

[Electrophoretic separation of glycosaminoglycans from different types of connective tissue and biological fluids]

Separation by means of electrophoresis on paper of glycoseaminoglycans from different types of human and animals connective tissue (bone tissue, synovial membrane of joints, skin and others) and from biological fluids (blood serum, urine, joint liquid) enabled to determine the ratio between sulphatated and nonsulphatated glycoseaminoglycans in normal conditions, in different pathological states and impairments of connective tissue structures. The method was found to be adequate for studies on quantitative and qualitative composition of glycoseaminoglycans and their metabolic products in pathologically altered connective tissue and biological fluids.

Type III collagen: A major constituent of rheumatoid and normal human synovial membrane

The findings establish that type III collagen is a major constituent of grossly proliferated rheumatoid and normal synovium. Unlike the collagen of normal synovium most of that in rheumatoid tissue could be solubilised by pepsin at 4 degrees C. Moore than half the pepsin-solubilised collage was identified as type III, the remainder being type I, by CM-cellulose chromatography; SDS-polyacrylamide electrophoresis with and without reduction of disulphide bonds; and amino acid analysis. Moreover, at least half the total collagen in several samples of normal as well as rheumatoid tissue was clearly type III when cyanogen bromide-derived peptides were run on SDS-polyacrylamide electrophoresis and compared with peptides prepared from purified types I and III collagens. This conclusion was supported by the isolation on phosphocellulose and quantitation by amino acid analysis of the collagen peptides alpha(1)CB2 and alpha(III)CB2 from a cyanogen bromide digest of rheumatoid synovium.

Osteoarticular changes and synovial biopsy findings in Wilson's disease

Images

Ultrastructural characteristics of the synovial membrane in idiopathic haemochromatosis

Images

Human cartilage lysozyme

The lysozyme content of human cartilage was measured by incubation of lyophilized, powdered cartilage in a variety of buffers and salt solutions, and the factors controlling the binding of lysozyme within cartilage were studied. Lysozyme was extracted from hyaline cartilage by buffers of pH greater than 9.0 by solutions 1 M in monovalent cations, and by solutions 0.12-0.40 M in divalent cations. The ability of cations to extract lysozyme from cartilage agreed with their known affinities for binding to chondroitin sulfate. The total extractable lysozyme content of five samples of human costal cartilage ranged from 1.45 to 3.36 mug lysozyme per mg of cartilage; for five samples of hyaline cartilage from peripheral joints the range was 0.80-3.03 mug lysozyme per mg of cartilage. Cartilage incubated in excess exogenous lysozyme could bind 0.053 equivalents of lysozyme per equivalent of chondroitin sulfate. Fibrocartilage and synovium from knee joints yielded no detectable lysozyme, despite the fact that synovium, a tissue rich in lysosomes, contained measurable quantities of beta-glucuronidase. Lysozyme extraction from cartilage was not augmented by incubation with streptolysin S. When incubation was carried out with mild extraction techniques, lysozyme extraction from cartilage tended to parallel uronic acid release, both as a function of time and from one specimen to another. The active material as lysozyme. Lysozyme occurs in human hyaline cartilage as a counterion to polyanionic glycosaminoglycans. Carextracted from cartilage met five criteria for identification tilage lysozyme appears to be extracellular and nonlysosomal. Degradation of cartilage may contribute to the increased serum and synovial fluid lysozyme levels often present in patients with rheumatoid arthritis.

Ultrastructure of synovial cells in vitro

Images

Immunofluorescent demonstration of intracellular fibrin in synovial tissue

Images