JPS633627B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an artificial organ and a method for manufacturing the same. More specifically, the present invention relates to artificial organs such as artificial kidneys, artificial lungs, and plasma separation devices that do not substantially cause transient leukopenia, and to methods for producing the same. (Prior art) Artificial organs such as artificial kidneys, artificial livers, artificial lungs, and plasma separation devices have been used in the past, and dialysis membranes such as hollow fiber membrane types and flat membrane types have been used in material exchange sites such as dialysis. As its excellent dialysis properties, mechanical strength,
Regenerated cellulose-based materials are widely used due to their cost and other considerations. However, artificial organs using such regenerated cellulose-based membranes, such as regenerated cellulose-based artificial kidneys, suffer from so-called transient leukopenia (hemodialysis), in which the number of white blood cells decreases temporarily and rapidly immediately after the start of dialysis.
leukopenia) and other side effects on living organisms, and the impact this has on patients cannot be ignored. (Problems to be Solved by the Invention) On the other hand, synthetic polymer membranes such as polymethyl methacrylate, polyacrylonitrile, ethylene-vinyl alcohol copolymer, and polycarbonate, which have recently been proposed as permeable membranes, have been proposed to prevent transient leukopenia. Although the degree of expression of ) etc. and performance, which not only limits the number of patients who can use it, but also increases cost, causes many pinholes during use, and limits sterilization methods. In order to solve the above-mentioned problems, it has been proposed to modify the surface of the regenerated cellulose membrane using heparin or the like, but satisfactory results have not yet been obtained. Accordingly, an object of the present invention is to provide an improved artificial organ and a method for manufacturing the same.
Another object of the present invention is to provide an artificial organ and a method for producing the same that have fewer side effects on living organisms. Still another object of the present invention is to provide an artificial organ that does not substantially cause transient leukopenia, and a method for manufacturing the same. (Means for Solving the Problems) These objectives are to provide a hollow fiber body fluid permeable membrane made of regenerated cellulose in an artificial organ, and vitamin E and This is achieved by an autoclaved artificial organ characterized by being coated with glycerin and filled with a liquid harmless to living organisms. In addition, these purposes are achieved by coating the regenerated cellulose hollow fiber body fluid flow area surface of a body fluid permeable membrane in an artificial organ with an organic solvent solution of vitamin E and glycerin, then removing the organic solvent, and then applying it to a living body. This can also be achieved by a method for manufacturing an artificial organ, which involves bringing a harmless liquid into contact with the side surface of the flow area and subjecting it to autoclave sterilization. Further, the present invention is a method for producing an artificial organ in which the organic solvent is a lower alcohol. Furthermore, the present invention provides that the concentration of fat-soluble vitamins in the organic solvent is from 0.01 to
This is a method for manufacturing an artificial organ with a concentration of 10 w/v%. Furthermore, the present invention is a method for producing an artificial organ, in which the concentration of glycerin in the organic solvent solution is 0.1 to 10 w/v%. In addition, the present invention provides that the liquid that is harmless to living organisms is
A sterilized artificial organ made of water, physiological saline, or an aqueous glycerin solution, and a method for producing the same. (Function) The artificial organ in the present invention includes an artificial kidney, an artificial liver, an artificial lung, a plasma separation device, etc., and preferably an artificial kidney. Next, one embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an example in which the artificial organ according to the present invention is used in an artificial kidney storage device, that is, a hollow fiber type dialyzer. This dialyzer 1 is constructed by inserting a hollow fiber bundle 5 made of a large number of hollow fibers into a cylindrical body 4, which has an inlet pipe 2 and an outlet pipe 3 for dialysate near both ends. It has a structure similar to a shell-and-tube type device in a heat exchanger, for example, in which both ends of the cylindrical body are sealed with potting agents 6 and 7 such as polyurethane, and both ends of the cylindrical body are sealed. Headers 10 and 11 each having an inlet 8 and an outlet 9 for blood are brought into contact with the headers 10 and 11, respectively, and the headers 10 and 11 are fixed to the cylindrical body 4 by caps 12 and 13, respectively. Tubes 14 and 15 connected to the human body are connected to the inlet 8 and the outlet 9. Therefore, the hollow system constituting the hollow fiber bundle 5 is a dialysis membrane, for example, a regenerated cellulose membrane,
Preferably, it is a cuprammonium regenerated cellulose membrane. According to the present invention, the circulation area of body fluids such as blood in the artificial kidney storage, that is, the space formed by the header 10 and the potting agent 6, the space formed by the header 10 and the potting agent 7, the header 11 and the potting agent 7, etc.
The space formed by this is filled with an organic solvent solution of fat-soluble vitamins and glycerin. After applying the solution to the interior of the hollow fiber membrane, the solution is discharged, and then dried to remove the organic solvent.
Furthermore, by flowing an aqueous solution that is harmless to the human body and then sterilizing the artificial organ by autoclave sterilization, a permeable membrane in which the side surface of the body fluid flow region of the body fluid permeable membrane is filled with the aqueous solution that is harmless to the human body can be obtained. Therefore, during use, the solution may be drained and washed with water if necessary. As a result, the second
As shown in the figure, a mixed coating 17 of fat-soluble vitamins and glycerin is formed on the inner surface of the hollow fiber membrane 16. The vitamin E used in the present invention is fat-soluble, and examples include α-tocopherol, β-tocopherol, γ-tocopherol,
Tocopherols such as δ-tocopherol, α-
Tocotrienol, β-tocotrienol, γ-
There are tocotrienols such as tocotrienol and δ-tocotrienol. The thickness of the vitamin E film is 0.001 to 0.1 μm, preferably 0.002 to 0.05 μm. Such vitamin E has a concentration of 0.01 to 10w/v
%, preferably 0.05 to 2.0 w/v%, as a solution in an organic solvent. Further, the concentration of glycerin in the solution is 0.1 to 10 w/v%, preferably 1 to 5 w/v%.
%. The solution is then discharged and removed, and after the discharge and removal, a gas inert to the vitamin E, such as air, nitrogen, carbon gas, etc., is introduced at a temperature of 10 to 80°C, preferably 15 to 30°C. By evaporating and removing the organic solvent, a coating of vitamin E and glycerin is formed on the contact surface. Examples of organic solvents used in the present invention include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol,
Examples include alcohols such as sec-butanol and 2-ethylhexanol, diethyl ether, ethyl acetate, and acetone, but lower alcohols are preferred, and ethanol is particularly preferred. The above explanation has mainly been about an artificial kidney, which is a dialyzer, but it goes without saying that it can also be used for other artificial organs such as an artificial liver, an artificial lung, and a plasma separation device. (Example) Next, the present invention will be described in further detail by giving examples. Example 1 Inner diameter approximately 200 μm, outer diameter approximately 220 μm, length 14-14.5 cm
368 copper ammonia regenerated cellulose hollow fibers were inserted into the cylindrical body 1 as shown in FIG.
Then, headers 10 and 11 were attached to both ends, and the caps 12 and 13 were used to secure the dialyzer (artificial kidney) 1. The inner membrane area of this product was 300 cm ² . On the other hand, vitamin E (DL-α-tocopherol)
1.0g and 2.0g of glycerin in 100ml of ethanol
An ethanol solution of vitamin E and glycerin was prepared by dissolving it in A 50 ml syringe was connected to one end of the dialyzer 1, and the other end was immersed in the vitamin E solution. Activate the plunger of the syringe to add vitamin E into the dialyzer.
It was filled with a solution of After filling, the container was left at room temperature for about 5 minutes. Next, the dialyzer was pulled up to discharge the vitamin E solution, an aspirator was connected, and the dialyzer was air-dried at a temperature of 25°C. Furthermore, in order to ensure complete drying, it was left in an oven at 60°C overnight. Thereafter, distilled water was filled, and the dialyzer in this state was placed in an autoclave and sterilized at a temperature of 115°C for 30 minutes. Example 2 A dialyzer was manufactured in the same manner as in Example 1 except that the concentration of vitamin E in the ethanol solution of vitamin E and glycerin was 0.1 w/v%. Comparative Example For comparison purposes, a dialyzer similar to Example 1 without treatment with an ethanol solution of vitamin E and glycerin was simply wetted by autoclaving. Example 3 Vitamin E (DL-α-trichopherol) was dissolved at a concentration of 1 w/v % ethanol and 1 w/v % glycerin, and a polystyrene plate was immersed in the resulting solution for 3 minutes, then taken out and left at room temperature. A sample was obtained by leaving it to dry completely. Similarly, vitamin E
Samples were obtained using a 0.1 w/v% ethanol solution.
These samples and untreated samples were evaluated by a platelet dilatation test. Evaluation by platelet dilatation test was performed by the following method. That is, the venous blood of a healthy person is 4.5
ml of blood was collected with a polypropylene syringe containing 0.5 ml of 3.8% sodium citrate, transferred to a polypropylene test tube, centrifuged at 800 rpm for 5 minutes, and diluted with diluent (saline saline: 3.8% saline). Sodium citrate = 9:1) was added to prepare a platelet suspension. Sample this liquid (0.4mm thick plate)
The solution was dropped into the solution and left for a certain period of time to allow platelets to adhere and expand. This was fixed with 2% glutaraldehyde, subjected to stepwise dehydration in an ethanol series, and observed under an electron microscope after drying. The evaluation method was to look at the number of platelets attached to 0.11 mm ² and changes in their morphology. Morphological changes were classified into the following three types. Type: The platelet's normal platelet shape, which is a disc, has become spherical and has 3 to 4 pseudopodia, and is thought to have relatively weak adhesion to the material surface. Type: A type with several or more pseudopodia extended and the cell body expanded to half of the pseudopod, which seems to have strongly adhered to the material surface. Type: One with a thin cell expanded to more than half the length of the pseudopod; the cell has expanded almost completely, exhibiting a circular shape, and appears to have completely adhered to the material surface. The test results are shown in Table 1.

[Table] Example 4 After measuring the weight of the rabbit, it was fixed in the dorsal position on a Kitajima type fixation table. Next, the hair in the surgical field was trimmed with electric clippers and wiped with alcohol cotton. An incision was made along the midline from submandibular to the clavicle with scissors, the fascia was further opened, and the right (left) common carotid artery was dissected, being careful not to damage nerves, branch vessels, and surrounding tissues. Next, the left (right) facial vein was carefully dissected in the same way, and a Terumo Corporation Surflow (registered trademark of Terumo Corporation) indwelling catheter with a rubber cap for mixed injection filled with 1 IU/ml heparinized saline was inserted. , fixed with ligation. Similarly, a catheter was also inserted into the artery and ligated and fixed. The weights of the test rabbits at this time were as shown in Table 2. Table 2 Sample weight (Kg) VE1.0% 2.53 VE0.1% 5.66 No treatment 2.58 Regarding rabbit 20 prepared in this way,
Experimental circuits were prepared using dialyzers 1 of Examples 1 and 2 and Comparative Example. i.e. rabbit 2
The catheter 21 connected to the artery of
2, a bypass catheter 23 is connected to the catheter 21, and the bypass catheter 23 is connected to the catheter 21.
was connected to the chamber 24 communicating with the out 25 side of the manometer, and further the chamber 24 and the vein of the rabbit 20 were connected with a catheter 26. The pump 22 and the dialyzer 1 are connected through a tube 27, and the tube 27 communicates with the inlet 28 side of the manometer. Further, the dialyzer 1 and the chamber 24 were connected through a tube 29. On the other hand, the dialysate inlet and outlet of the dialyzer 1 were connected by a tube 30, a pump 31 was installed in the tube 30, and the dialyzer 1 was immersed in a water bath 32 at 37°C.
The thus constructed circuit was subjected to priming cleaning with 1 IU/ml heparinized saline (100 ml). The collected blood was diluted 2 times with 1.5% EDTA-3K saline and calculated using ELT-8 (Ortho Instrument). The white blood cell count (WBC), platelet count (PLT) and hematocrit value (HCT) obtained as a result are shown in Tables 3 to 5. In addition, white blood cell count,
The platelet count is calculated by correcting the HCT value using the following formula:
It was expressed as the HCT value before the start of circulation. Cx=CoHCTx/HCTo However, the symbols in the formula are as follows. Cx: Correction value Co: Actual measurement at low altitude HCTx: Correction reference Hct ground = initial Hct value HCTo: Hct value when Co value is obtained

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[Table] Figure 4 shows the changes over time in the number of white blood cells obtained from the above results. In the same figure, curve A is for vitamin E 1.0%, and curve B is for vitamin E.
Curve C shows the case of 0.1% E and the case of 0% vitamin E, respectively. Furthermore, the change in platelet count over time is shown in FIG. In the same figure, curve D is for vitamin E 1.0%, curve E is for vitamin E
Curve F shows the case of 0.1% E and the case of 0% vitamin E, respectively. (a) A permeable membrane coated with an ethanol solution containing 1.0 w/v% of vitamin E and 2.0 w/v% of glycerin obtained in Example 1, (b) 20 w/v% of glycerin was not used in Example 1; The UFR values were measured for dialyzers prepared using a permeable membrane coated in the same manner as above and a permeable membrane not coated with (c) vitamin E and glycerin, respectively, and the UFR values were as shown in Table 6. Table 6 Coating conditions UFR (ml/mmHg・hr) Simultaneous coating of vitamin E and glycerin 4.2 Coating of vitamin E alone 3.8 No coating 4.2 As is clear from Table 6, when fat-soluble vitamins and glycerin are coated at the same time, The UFR value was maintained higher than when the fat-soluble vitamin was coated alone, and no deterioration in dialysis performance was observed.
(a) Dialyzer obtained in Example 1 (autoclave sterilized) and (e) Dialyzer prepared in the same manner as Example 1 except that it was not filled with distilled water and sterilized with ethylene oxide gas instead of autoclave sterilization. When an extracorporeal blood circulation test was performed and the number of white blood cells was measured, the results shown in Table 7 were obtained. Table 7 White blood cell count (PIC value) Sterilization method : Average ± ISD (d) Autoclave sterilization 71.2 ± 6.4% (e) Ethylene oxide sterilization 70.0 ± 20.4% As is clear from Table 7, products coated with fat-soluble vitamins When sterilized by autoclaving, the white blood cell count becomes much more stable and has less variation than other sterilization treatments. (Effects of the invention) As described above, the artificial organ according to the present invention has
A hollow fiber body fluid permeable membrane made of regenerated cellulose in an artificial organ, a coating of vitamin E and glycerin formed on the side surface of the body fluid circulation area of the body fluid permeable membrane, and a liquid harmless to living organisms filled in the artificial organ. Since this is an autoclave-sterilized artificial organ characterized by In particular, when blood comes into contact with blood, albumin in the blood adheres to the vitamin E layer and produces anticoagulant properties, resulting in a condition in which white blood cells recognize the dialysis membrane as a foreign object and decrease, so-called transient leukopenia. Furthermore, since glycerin is used, the physical properties of the permeable membrane, especially the regenerated cellulose membrane, such as hydrophilicity, dialyzability, and mechanical strength, can be maintained by its action. Therefore, it is possible to reduce the risk of infection, which conventionally was high due to a decrease in white blood cells at the initial stage of use. In addition, vitamin E in particular shows an excellent effect on suppressing platelet expansion in addition to the above-mentioned transient leukopenia. Furthermore, since glycerin is also coated with the vitamin E, the UFR is higher than when vitamin E is coated alone due to the action of the glycerin.
The value could be maintained at a high level, and no deterioration in dialysis performance was observed. Therefore, the artificial organ according to the present invention exhibits excellent effects especially when used as an artificial kidney.
In addition, since the artificial organ according to the present invention is coated with vitamin E and glycerin after being sterilized in an autoclave, there is no need to sterilize it before dialysis. Not only does vitamin E not dissolve into the product, but since the sterilization is done by autoclaving, unlike other sterilization methods, there is extremely little variation in the number of white blood cells, and the stability of the resulting product is greatly improved. Furthermore, the method for manufacturing an artificial organ according to the present invention includes coating the side surface of the body fluid flow area of a hollow fiber body fluid permeable membrane made of regenerated cellulose in the artificial organ with an organic solvent solution of vitamin E and glycerin, and then removing the organic solvent. Furthermore, since it is made by contacting the side surface of the flow area with a liquid that is harmless to living organisms and performing autoclave sterilization, the coating process is easy, and therefore the cost can be reduced, and there is no chemical reaction during coating. Since this method does not require any coating, there is less possibility of contamination of the artificial organ due to the covering operation. In addition, side effects on living organisms due to the action of vitamin E used,
For example, it can alleviate transient leukopenia, and it can also exhibit excellent effects on platelet expansion inhibition. Furthermore, since sterilization is performed by autoclave sterilization, there is extremely little variation in white blood cell count, which is different from other sterilization methods, and the stability of the resulting product is greatly improved.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view showing an embodiment of the artificial organ according to the present invention, FIG. 2 is a longitudinal cross-sectional view of a hollow fiber, and FIG. 3 is a perspective view showing an embodiment of the artificial organ according to the present invention. In the experimental circuit, FIG. 4 is a graph showing changes over time in the number of white blood cells, and FIG. 5 is a graph showing changes over time in the number of platelets. 1... dialyzer, 4... cylindrical body, 5...
...Hollow fiber, 6,7...Potting agent, 10,1
1... header, 12, 13... cap.

Claims (1)

[Scope of Claims] 1. A hollow fiber body fluid permeable membrane made of regenerated cellulose in an artificial organ, a coating of vitamin E and glycerin formed on the side surface of the body fluid flow area of the body fluid permeable membrane, and a coating of vitamin E and glycerin filled in the artificial organ. An autoclaved artificial organ characterized by being made of a liquid that is harmless to living organisms. 2. The artificial organ according to claim 1, wherein the liquid harmless to living organisms is water, physiological saline, or aqueous glycerin solution. 3. The sides of the body fluid flow area of a hollow fiber body fluid permeable membrane made of regenerated cellulose in an artificial organ are coated with an organic solvent solution of vitamin E and glycerin, and then the organic solvent is removed, and a liquid that is harmless to the living body is added to the body fluid flow area. A method for producing an artificial organ, which is made by contacting the sides and subjecting it to autoclave sterilization. 4. The method for manufacturing an artificial organ according to claim 3, wherein the organic solvent is a lower alcohol. 5 The concentration of fat-soluble vitamins in the organic solvent is 0.01
The method for manufacturing an artificial organ according to claim 3 or 4, wherein the content is ~10 w/v%. 6 The concentration of glycerin in the organic solvent solution is 0.1~
The method for manufacturing an artificial organ according to any one of claims 3 to 5, wherein the content is 10 w/v%. 7. The method for manufacturing an artificial organ according to any one of claims 3 to 6, wherein the liquid harmless to living bodies comprises water, physiological saline, or an aqueous glycerin solution.