Characterization of the Proteins of Human Synovial Fluid in Certain Disease States 1

Abstract

In search of the similarities and differences between blood plasma and synovial fluid, on one hand, and normal and pathological joint fluid on the other, it appeared important to investigate systematically the protein components of joint fluid. Investigations of the synovial fluid proteins by electrophoresis have been carried out by several authors (1-4). The identification of these proteins has been initiated (1,5). Fractionation with ammonium sulfate to obtain the albuminglobulin ratio (6) and demonstration of definite properties of certain proteins by immunochemical methods and enzymatic reactions have been reported (1,5).This publication presents a study on the characterization of the proteins in pathological synovial fluids. MATERIALS AND METHODSThe collection of synovial fluid and plasma as well as the procedure for the fractionation of their proteins have been described in a previous publication (7). All fluids were drawn from knee joints of patients with rheumatoid or traumatic arthritis or neuroarthropathy, and were obtained through the courtesy of the clinical staff of the Arthritis Unit. Most of the fluids deposited a precipitate within 20 hours although acid-citrate-dextrose (ACD) solution had been added. Prior to fractionation the joint fluids were treated with hyaluronidase (7).The electrophoretic and ultracentrifugal analyses were carried out in a Perkin-Elmer electrophoresis apparatus and a Spinco Model E ultracentrifuge, respectively. Paper electrophoresis was performed essentially according to the method of Grassmann and Hannig (8,9). After being heated at 110°for 10 minutes, the paper ing 2 per cent agar, for 17 hours at 180 V and 40 mA. The arrow "Electroph." indicates the direction of the electrophoretic movement of the proteins, and the arrow "Endosmosis" indicates the direction of the electroendosmosis. After the electrophoresis was completed, the troughs between the agar sections were filled with horse serum against human serum. Therefore, the precipitin zones formed symmetrical patterns. The positions of albumin and 7-globulin were found by applying these proteins as references on adjoining sections. The precipitin zones of synovial fluid (a) appeared less intense than those of the serum because of its lower protein concentration. The line corresponding to albumin, however, was very distinct due to the relatively high albumin concentration in this joint fluid.Whatman No. 1 paper (24 cm. wide) soaked in the borate buffer were used as electric connection between the ends of the agar plate and the adjoining borate buffer reservoirs. The buffer chambers, in turn, were again connected to holes filled with glass wool with a second set of buffer chambers in which the electrodes were placed. The electrodes were made by winding 120 cm. of stainless steel wire (0.05 cm.) around a glass tube with diameter of 1.5 cm. To secure an even level of the buffer in all 4 compartments, the two inner reservoirs were connected with each other by a thin rubber tubing. After half an hour of temperature equilibra...

Lipoproteins containing apoprotein B are a major regulator of neutrophil responses to monosodium urate crystals.

“…It has been suggested that LDL is a major plasma regulator of HeLa cell adhesion to glass (62), which is a negatively charged surface like monosodium urate crystals. In addition, there is evidence that human serum enhances the stimulation by urate crystals ofnonmitogenic synovial fibroblast responses in vitro (63,64 (19,(55)(56)(57)(58), LDL may well represent an important factor in modulation of gouty inflammation.…”

“…Since most synovial fluid proteins are present in plasma (19), and plasma and serum have a more constant composition than gouty synovial fluid (19,20), investigators have focused on serum and plasma effects on neutrophil-crystal interaction. Serum profoundly inhibits urate crystal-induced neutrophil lysis (18) and a serum coat has been shown by Abramson et al (7) to reduce urate crystal-induced superoxide generation.…”

The proteins of synovial fluid: A study of the α1/α2 globulin ratio

“…and 20" C. The psthological joint fluids and sera were diluted before centrifugation with 0. 15 N NaCl so that a protein concentration of approximately 1.5 per cent was obtained. The enlarged tracings of the patterns revealing three or four peaks were resolved in Gaussian curves.…”

The Mechanism of Blockade of the Reticuloendothelial System

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