Effect of Membrane Trapping in Plasma Fractionator on Separative Characteristics

Abstract

Several kinds of plasma fractionators have been introduced to actively separate protein fractions between albumin and globulins in double filtration plasmapheresis. However, relatively large molecular weight proteins are known to be partially trapped by the membrane in a plasma fractionator. In this paper, effects of membrane trapping on separation characteristics in plasma fractionators were examined during in vitro and in vivo studies. All in vitro experiments were done with a closed circuit under constant-flow rate filtration. Protein concentration in feed tank kept constant at no filtration in AS-14H, Evaflux 4A and 2A, while 20-40% of IgG and 40-60% of beta-lipoprotein in 2 liter plasma were removed by membrane trapping for 300 min when filtration fraction equaled 0.87. Protein plugging to the membrane seems to be a major factor in these proteins. And, Dead-end and Partially Discarded modalities with relatively high filtration fraction are effective for the separation between albumin and globulin. Twenty-seven DFPP treatments in 13 patients with autoimmune diseases were done to allow us to estimate the effects of membrane trapping during an in vivo study. All treatments using 6 types of plasma fractionator were performed under constant operating conditions with Partially Discarded modality. In any plasma fractionator, beta-lipoprotein was fairly trapped at 30 min after the start of treatment.

Fibrinogen Reduction During Selective Plasma Exchange due to Membrane Fouling

“…This was similar to the results of an increase in SC of fibrinogen using the DF Thermo method with an Evaflux‐5A plasma fractionator until the PPV was 3.0 L . Usually, SC of proteins in the membrane separator decreases after the treatment is initiated . In the present study, if the PPV had been much higher, SC of fibrinogen may have started to decrease, similar to the previous study .…”

VLDL/LDL acts as a drug carrier and regulates the transport and metabolism of drugs in the body

“…FH is characterized by the accumulation of VLDL/LDL particles in the blood because of genetic dysfunction of LDLR or LDLR-related genes 15 . Therefore, lipoprotein apheresis treatment is important to prevent the onset of atherosclerosis and cardiovascular disease in patients with FH 16–19 . Lipoprotein apheresis treatment can selectively remove VLDL/LDL cholesterol from blood through the electrostatic interaction of dextran sulfate in the lipoprotein apheresis column with apoB on (V)LDL particles 20 .…”

“…Lipoprotein apheresis treatment is vital to FH patients because the presence of abnormally high LDL cholesterol leads to the formation of atherosclerotic plaques and increases the risk of cardiovascular diseases 16–19 . Lipoprotein apheresis treatment is currently believed to selectively eliminate VLDL/LDL cholesterol 20 .…”

Proteomic Analysis of Proteins Eliminated by Low‐Density Lipoprotein Apheresis

“…DeGenne et al conducted plasma exchange (PE) in homozygous FH patients in 1967 (3), and in 1975 Thompson et al reported the LDL-C-reducing effects of PE on the alleviation of angina pain with the improvement of coronary artery stenosis (4). Subsequently, attempts to remove LDL in more selective ways have been made by using a special double-filtration plasmapheresis (DFPP) method termed thermofiltration (5)(6)(7) and an LDL adsorption column (8,9). Collectively, these two methods have been called LDL-apheresis (LDL-A).…”