JPS6155882B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for preserving and thawing organs, which is capable of processing various organs extracted from the human body so that they can be stored, and thawing stored organs for timely transplantation.

Conventionally, extracted organs have been preserved until transplantation, and the preservation method involves injecting Collins fluid at a temperature of approximately 4°C, which has properties similar to blood, through the organ's artery or portal vein. A so-called perfusion method is known that drains this through the veins.
The organ after such perfusion treatment is stored under the above-mentioned temperature condition of about 4° C., and blood flow is applied to the stored organ at the time of transplantation before use.

However, when using this preservation method, organs can only be preserved for about 12 hours, which makes it difficult to coordinate the time between organ donation and demand, creating a major bottleneck in saving human lives.

Therefore, in order to extend the storage time, it is possible to freeze the organ by setting the storage temperature to a low temperature, but freezing the organ subjected to the above conventional method will cause cell destruction and cause the organ itself to die. Become.

In view of the above points, the present invention has been devised as an apparatus that enables semi-permanent preservation by freezing extracted organs without causing cell destruction, and which can also be used to thaw organs when transplanting them. Its purpose is to provide the following.

To describe the present invention in detail with reference to the illustrated embodiment, a heat insulating container 2 capable of storing an extracted organ 1 has an opening/closing door 3, and the container 2 and the perfusion freezing/thawing section 4 are in the same part. The inflow pipe 6 is connected to the fluid supply pipe 5 of the organ 1 and connected to the fluid supply pipe 5 of the organ 1 .
is connected to the artery 1a or the portal vein 1b, and further connected to the vein 1
A discharge pipe 7 extending through the heat insulating container 2 is connected to c, and an air supply pipe 9 of the perfusion freezing and thawing section 4 is connected to an air supply nozzle 8 provided in the same container 2. used.

In the perfusion freezing device 4 shown in FIG. 1, liquid nitrogen LN ₂ is stored between an insulated outer tank 10 and an intermediate tank 11, and the intermediate tank 11 and an inner tank contain a refrigerant 12 such as fluorocarbon. 13, there is provided a cooling tank 14 in which helium gas GHe is sealed, and the tank 14 is first provided with a liquid agent supply mechanism A.

The mechanism A shown in the figure includes first, second, and third containers 15, 16, each containing Corinth liquid, dimethyl sulfoxide (DMSO) or glycerin, and alcohol in the refrigerant 12, respectively.
17 is immersed, and under the control of the controller 18, the first, second, and third on-off valves 19, 2 provided in the outflow pipes of the same containers 15, 16, 17 are immersed.
0 and 21 are opened and closed at appropriate times, and the pump 22 provided in the fluid supply pipe 5 is operated to selectively supply the Collins solution, DMSO, and alcohol to the organ 1.
can be supplied to the artery 1a or the portal vein 1b.

On the other hand, the liquid supply mechanism A schematically shown in FIG.
6 and 17 are provided outside the cooling tank 14, and a heat exchange section 23 formed between the first, second, and third on-off valves 19, 20, 21 and the pump 22 is connected to the cooling tank 1.
It has a configuration in which it is immersed in the refrigerant 12 of No. 4.

Furthermore, the cooling tank 14 is provided with a refrigerant temperature control mechanism B that can freely adjust the temperature of the refrigerant 12, and in the illustrated example, a temperature sensor 24 immersed in the refrigerant 12, a stirrer 25, and an electric heater. 2
6, the sensor 24 and the electric heater 2
6 is connected to the controller 18, and 25' in the figure represents the motor of the stirrer 25.

Furthermore, the cooling tank 14 is provided with an organ temperature control mechanism C, which has a structure in which LN is transferred from an organ refrigerant cylinder 27 containing liquid nitrogen or the like to an air supply container 28 immersed in the refrigerant 12. ₂ is supplied, and the LN ₂ flowing out from the same container 28 is converted into nitrogen gas GN ₂ whose temperature is adjusted to a desired temperature by a heat exchanger 29.
As, the air supply nozzle 8 is passed through the air supply pipe 9.
In the figure, 30 indicates an on-off valve provided in the fluid supply pipe 5.

Therefore, in order to use the above-mentioned device, the controller 18 first opens the first on-off valve 19, and the pump 22 is operated to supply a blood equalization perfusion solution such as Collins solution from the first container 15. will flow into the organ 1 from the artery 1a or portal vein 1b of the organ 1, and will be discharged to the outside from the vein 1c. By controlling and adjusting the temperature of the refrigerant 12, the injection is performed while gradually lowering the temperature.

In other words, the extracted organ 1 is initially at approximately body temperature37
℃, the temperature of the blood-equalizing perfusate is gradually lowered from the body temperature, and by injecting the perfusate, the blood in organ 1 is drained and replaced with the same perfusate. , the first like this
The perfusion process continues until the blood homologous perfusate is at a first near-decreased temperature below its freezing point.

Here, the adjustment of the temperature drop is performed by controlling the refrigerant 12, which is being cooled from the LN ₂ in the outer tank 10 through the GHe in the intermediate tank 11, as described above, by the refrigerant temperature control mechanism B. Since the freezing point of Collins solution is approximately 0°C, the temperature in the first perfusion step is approximately 1~1°C.
It is sufficient to control the temperature drop so that the first neighborhood temperature drop is about 2°C. For example, in order to lower the temperature of the blood perfusate from the body temperature of 37°C to 2°C, the temperature drop rate should be 3.5°C.
°C/min and the perfusion time can be approximately 10 minutes.

At this point, by operating the heat exchanger 29, the temperature-controlled GN ₂ is ejected from the air supply nozzle 8. This is to make the temperature equal to that of the perfusate and to prevent a temperature gradient between the internal and external temperatures of the organ 1, and this will continue in the following steps.

Next, the first on-off valve 19 is controlled to close and the second on-off valve 20 is opened, and the antifreeze damage agent such as dimethyl sulfoxide and glycerin in the second container 16 is replaced with the blood equalization perfusion liquid. The second perfusion step is then carried out to supply and perfuse the organ 1.

In the same process, the antifreeze agent is first added to the
By controlling this temperature with the refrigerant temperature control mechanism B, the temperature is gradually lowered, and the temperature of the antifreeze damage agent becomes the second temperature drop below its freezing point. Continue this until.

Since the freezing point of DMSO is approximately -5℃,
The temperature drop in the second neighborhood is preferably about -4℃,
In fact, in order to lower the temperature from 2°C to -4°C, which is the first temperature drop in the first vicinity, the perfusion time can be set at 0.3°C/min for about 20 minutes, and by perfusion of such antifreeze agent, Due to the osmotic pressure difference between the agent and the water in the cells of organ 1, the water is sufficiently absorbed by the antifreeze agent.

Once the second perfusion step is completed, the third perfusion step is started, in which the second on-off valve 20 is closed, the third on-off valve 21 is opened, and the antifreeze agent is replaced with the alcohol, etc. A final perfusate with a lower freezing point than the inhibitor is supplied for perfusion.

Therefore, in this step as well, the temperature of the final perfusate is controlled to gradually decrease from the second temperature drop (-4°C), and the perfusion brings the final perfusate to a third temperature below its freezing point. Perfusion continues until the perfusion fluid freezes and perfusion is stopped; in the case of alcohol, the freezing point is approximately -80°C.
For example, -60°C may be set as the third neighborhood drop temperature or -80°C.

In fact, this third perfusion step is 0.1℃/mi to lower the temperature of alcohol from -4℃ to -37℃.
By multiplying the perfusion time of approximately 330 minutes by the rate of descent of n, and further increasing the temperature by 5℃/
The drop rate may be 1 min, and the perfusion time may be approximately 5 min.

The frozen organs obtained through the first to third perfusion steps above will be stored in the frozen state.
This can be done by storing the frozen organ in a freezer at about -80° C. in the case of the above example, or by storing it by immersing it in a liquefied gas such as liquid nitrogen.

Now, the frozen organs stored in this way will be thawed and used for transplantation, but the means for thawing is carried out by substantially reversing the freezing process described above. can do.

That is, the frozen organ is removed from the storage site and set in the state shown in FIG.
At this time, first, by gradually raising the atmospheric temperature in the heat insulating container 2, the final perfusate such as alcohol present in the blood vessels of the organ concerned is raised to a temperature above its freezing point and thawed, and then the third opening/closing step is performed. When the valve 21 is opened, alcohol or the like is perfused by the pump 22.

In this first thawing perfusion step, the temperature of the final perfusion liquid is gradually raised by the refrigerant temperature control mechanism B until the temperature reaches the second neighborhood drop temperature (-4
The process continues until the temperature reaches ℃).

Next, the process will move on to the second thawing perfusion step in which the above-mentioned cryoprotectant is perfused in place of the final perfusion solution, but here too, the temperature is gradually raised from the second neighborhood drop temperature (-4°C). The perfusion is continued until the temperature of the antifreeze reaches the first temperature drop (1 to 2° C.).

Furthermore, in place of the above-mentioned anti-freezing agent, a blood equalization perfusion solution such as the above-mentioned Collins solution is perfused while gradually raising the temperature from the above-mentioned first neighborhood drop temperature.
The thaw-perfusion step is continued until the blood-isolated perfusate is at about body temperature.

The organ that has undergone the complete thawing and perfusion process can be supplied with the necessary blood and used for transplantation.

The present invention, as embodied by the above embodiments,
The perfusion freezing and thawing section 4 is equipped with a perfusion freezing and thawing section 4 and an insulating container 2 in which the organ 1 can be freely put in and taken out.
Then, a refrigerant temperature control mechanism B whose temperature of the refrigerant 12 can be freely adjusted by a controller 18, and an air supply container 28 to which refrigerant is supplied from an organ refrigerant cylinder 27 are immersed in the refrigerant 12 in the cooling tank 14. In addition, this air supply container 28 includes an organ temperature control mechanism C connected to the air supply pipe 9 via a heat exchanger 29, a first container 15 for blood perfusion liquid such as Collins solution, dimethyl sulfoxide, A second container 16 for a cryoprotectant such as glycerin, a third container 17 for a final irrigation fluid with a low freezing point such as alcohol, and a controller 18
and a liquid agent supply mechanism A that selectively flows out the liquid agent to the flowing liquid supply pipe 5 under the control of The fluid supply pipe 5 of the fluid supply mechanism A can be freely connected to the artery 1a or the portal vein 1b of the organ 1 in the insulated container 2, and can be freely connected to the artery 1a or portal vein 1b of the organ 1.
Since the discharge pipe 7, which can be freely connected to the insulating container 2, extends outside the heat-insulating container 2, the temperature of the refrigerant 12 can be freely adjusted by the refrigerant temperature control mechanism B, and the adjusted temperature allows uniform blood perfusion. Liquid, cold damage preventive agent, and low-freezing point final irrigation liquid can be sent to the organ 1 by the liquid supply mechanism A in a timely manner, and the temperature inside the heat-insulating container 2 can also be adjusted by the organ temperature control mechanism C. Therefore, the perfusion to organ 1 is
This can be done without undesired temperature gradients,
The preservation method and thawing method already described in detail can be carried out without any problem.

[Brief explanation of the drawing]

FIG. 1 is a partially longitudinal structural explanatory diagram of one embodiment of the apparatus for preserving and thawing organs according to the present invention, and FIG. 2 is a structural explanatory diagram of main parts showing another embodiment of the same apparatus. DESCRIPTION OF SYMBOLS 1... Organ, 2... Insulated container, 4... Perfusion freezing and thawing section, 5... Fluid supply pipe, 7... Discharge pipe, 8... Air supply nozzle, 9... Air supply pipe, 12
... Refrigerant, 14 ... Cooling tank, 15 ... First container,
16...Second container, 17...Third container, 18...
Controller, 19...First on-off valve, 20...
Second on-off valve, 21...Third on-off valve, 22...Pump, 23...Heat exchange section, 24...Temperature sensor,
25... Stirrer, 26... Electric heater, 27...
... Organ refrigerant cylinder, 28 ... Air supply container, 29
...Heat exchanger, A...Liquid supply mechanism, B...Temperature control mechanism for refrigerant, C...Temperature control mechanism for organs.

Claims (1)

[Scope of Claims] 1. A perfusion freeze-thaw section and an insulated container in which internal organs can be freely removed. A refrigerant temperature control mechanism that can freely adjust the temperature of an organ temperature control mechanism connected to the air supply pipe; a first container for a blood homogenizing perfusate such as Collins'solution; a second container for a cryoprotectant such as dimethyl sulfoxide or glycerin; and a second container for a low freezing point final perfusate such as alcohol. a liquid agent supply mechanism for selectively flowing the liquid agent from a third container into a flowing liquid supply pipe under the control of a controller, and the air supply pipe of the organ temperature control mechanism is connected to an air supply nozzle in the heat insulating container. At the same time, the fluid supply pipe of the liquid supply mechanism can be freely connected to the artery or portal vein of an organ within the same insulated container, and the discharge pipe, which can be freely connected to the vein of the organ, is extended outside the insulated container. A device for preserving and thawing organs, characterized in that the organ is extracted. 2. The apparatus for preserving and thawing organs according to claim 1, wherein the refrigerant temperature control mechanism includes a temperature sensor connected to a controller, an electric heater, and a stirrer. 3. The first, second, and third containers of the liquid supply mechanism are immersed in the refrigerant in the cooling tank, and the opening and closing of the first, second, and third on-off valves provided for each container are controlled by the controller. An apparatus for preserving and thawing an organ according to claim 1. 4. The organ according to claim 1, wherein the heat exchange section formed between the first, second, and third on-off valves of the liquid supply mechanism and the pump is immersed in a refrigerant in a cooling tank. equipment for preserving and thawing.