CN115212234A

CN115212234A - Application of fibroreticulocyte-derived exosome in preparation of medicine for treating and/or preventing sepsis acute kidney injury

Info

Publication number: CN115212234A
Application number: CN202111236011.6A
Authority: CN
Inventors: 李一鸣; 彭志勇; 张婧; 锁进猛; 柳叶; 胡畅; 汪枫云
Original assignee: Zhongnan Hospital of Wuhan University
Current assignee: Zhongnan Hospital of Wuhan University
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2022-10-21
Anticipated expiration: 2041-10-22
Also published as: CN115212234B

Abstract

The invention provides application of an exosome derived from fibroreticulocyte in preparing a medicament for treating and/or preventing acute kidney injury caused by sepsis. The invention extracts the exosome from FRCs for the first time; experiments show that the exosome derived from the FRCs can play a role in protecting renal injury, promote the injury repair of injured renal tubular cells, promote the proliferation of the injured renal tubular cells, reduce the necrosis of the renal tubular cells, relieve inflammatory reaction and reduce oxidative stress. The exosome derived from the FRCs is applied to the treatment of acute kidney injury caused by mouse sepsis, and obtains good treatment effect. Therefore, the fibroreticulocyte-derived exosome can be used for preparing a medicament for treating and/or preventing sepsis acute kidney injury. Compared with the traditional cell therapy, the exosome has the characteristics of good stability and convenience and quickness in storage and application.

Description

Application of fibroreticulocyte-derived exosome in preparation of medicine for treating and/or preventing sepsis acute kidney injury

Technical Field

The invention relates to the technical field of biomedicine, in particular to application of an exosome derived from fibroreticulocyte in preparation of a medicament for treating and/or preventing acute kidney injury caused by sepsis.

Background

Sepsis (Sepsis) is a multiple organ dysfunction syndrome in which the body's response to infection is disordered due to infection of the body by various pathogens, trauma, burns, major surgery, etc., resulting in a severe, complex, uncontrolled immune response and life threatening. The Kidney is the organ most susceptible to sepsis, and about 50% of sepsis patients develop Acute Kidney Injury (AKI). Despite the use of a number of antibiotics and organ support therapies, the incidence of sepsis AKI is still increasing and the medical resources consumed are increasing year by year due to the unclear pathogenesis and lack of specific therapeutic approaches. Therefore, the method deeply researches the pathogenesis of the sepsis AKI, continuously searches a new treatment target point, improves the prognosis of the sepsis AKI, and has important social benefit and economic benefit.

Therefore, there is an urgent need to develop a drug for treating and/or preventing sepsis acute kidney injury.

Disclosure of Invention

The invention aims to provide application of exosome derived from fibroreticular cells in preparation of a medicament for treating and/or preventing acute kidney injury caused by sepsis. .

In order to realize the purpose, the invention adopts the following technical scheme:

in a first aspect of the invention, there is provided the use of fibroreticulocyte-derived exosomes in the preparation of a medicament for treating and/or preventing sepsis acute kidney injury.

Further, the preparation method of the fibroreticulocyte-derived exosome comprises the following steps:

obtaining fibroreticular cells;

culturing the fibroreticular cells by using a culture medium containing serum without exosomes to obtain cell supernatant, then carrying out first solid-liquid separation to obtain supernatant, carrying out second solid-liquid separation on the supernatant to obtain solids, and then carrying out resuspension to obtain the exosomes derived from the fibroreticular cells.

Further, the obtaining of fibroreticulocytes comprises:

collecting adipose tissues, cutting into pieces, digesting, screening by a cell sieve, stopping digestion, removing red blood cells and granulocytes by a density gradient centrifugation method, and culturing the collected cells by adopting a DMEM complete culture medium containing FBS and subculturing to obtain the fibroreticular cells.

Further, in the digestion, a mixture of 0.2. + -. 0.02% collagenase, 2.0. + -. 0.5mg/ml neutral protease and 0.08. + -. 0.01mg/ml hyaluronidase is used for digestion.

Further, the first solid-liquid separation employs 0.2 μ M filtration.

Further, the second solid-liquid separation comprises: ultracentrifugation is carried out for 60 plus or minus 20min at the temperature of 4 plus or minus 2 ℃, and the rotating speed of the ultracentrifugation is 1.0 multiplied by 10 ⁵ g±1000g。

Further, the culture medium containing the exosome-free serum is a DMEM complete medium containing 0.5-1.5% of P/S, 0.05-0.15% of PB, 45-55. Mu.M EGF, 0.1-0.3mg/mLFGF, 50-150nM TGF, 8-12% exosome-free serum.

Further, the marker antibodies of the fiber reticulocyte are CD45-, PDPN + and CD31-.

Further, the reticulocyte-derived exosome-specific markers are CD9, CD63, HSP70, TSG-101, and CD81.

In a second aspect of the invention, there is provided a medicament comprising fibroreticulocyte-derived exosomes for use in the treatment and/or prevention of sepsis acute kidney injury.

One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:

the invention provides application of exosome derived from fibroreticular cells in preparation of a medicament for treating and/or preventing acute kidney injury caused by sepsis, wherein the exosome derived from FRCs is extracted for the first time; experiments show that the exosome from the FRCs can play a role in protecting renal injury, promote the injury repair of injured renal tubular cells, promote the proliferation of the injured renal tubular cells, reduce the renal tubular necrosis, relieve the inflammatory reaction and reduce the oxidative stress. The exosome derived from the FRCs is applied to the treatment of acute kidney injury caused by mouse sepsis, and obtains good treatment effect. Compared with the traditional cell therapy, the exosome has the characteristics of good stability and convenience and quickness in storage and application.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.

FIG. 1 shows the results of primary isolation culture and identification of FRCs in example 1, in which FIG. 1A shows the lymphoid structure in mouse mesenteric adipose tissue; FIG. 1B shows the observation of cell morphology of FRCs in bright field; FIG. 1C shows CD45, podoplanin, CD31 antibody labeled FRCs, flow cytometry to identify FRCs;

FIG. 2 shows the results of the extraction and identification of FRCs-exosomes in example 1; wherein, FIG. 2A shows the size and shape of exosomes detected by electron microscope; FIG. 2B shows Western blot detection of exosome (2 repeats) marker proteins CD63, CD9, TSG101 and HSP70; FIG. 2C shows the Nanoparticle Tracking Analysis (NTA) technique detecting the diameter of the extracted extracellular vesicles; FIG. 2D shows the differentiation of fat-forming induced differentiation medium into FRCs, oil red O staining adipocytes, red being differentiation of FRCs into adipocytes;

FIG. 3 is a graph of the results of the ability of FRCs-exosomes of example 2 to home to an injured kidney, wherein FIG. 3A is a graph of in vivo imaging to observe the site of FRCs aggregation in mice; FIG. 3B flow cytometry is used to detect the concentration of injected FRCs in peritoneal lavage fluid, spleen, kidney tissue; FIG. 3C shows Dio (Green fluorescence) labeled FRCs co-cultured with tubular epithelial cells, FRCs and tubular epithelial cells co-cultured for 24 hours using a Transwell chamber, dio labeled FRCs-Exos added to tubular epithelial cells, DAPI stained tubular epithelial cell nuclei, and exosome uptake observed by confocal microscopy;

FIG. 4 is the results of the protective effect of FRCs-derived exosomes on sepsis AKI in example 2, in which FIG. 4A FRCs and FRCs-exosomes (Exos) were injected into the abdominal cavity of sepsis mice, and the change in survival rate of sepsis mice at 120h was observed; FIG. 4B shows the measurement of serum creatinine and urea nitrogen levels in each group of mice;

FIG. 5 is the results of the improvement of LPS-induced sepsis by FRCs-exosomes in example 2.

Detailed Description

The present invention will be specifically explained below in conjunction with specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly presented thereby. It will be understood by those skilled in the art that these specific embodiments and examples are illustrative of the invention and are not to be construed as limiting the invention.

Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be obtained by an existing method.

In order to solve the technical problems, the general idea of the embodiment of the application is as follows:

exosomes are released outside cells in an exocrine form after being fused with cell membranes by intracellular Multivesicular Bodies (Multivesicular Bodies), lipid membrane microvesicles with the diameter of about 40nm-100nm enter receptor cells through endocytosis, direct membrane fusion or receptor ligand interaction, and carry out information transfer among cells.

1. The inventor of the application analyzes that the compositions of the exosomes from different sources greatly differ, and the exosomes from different sources have different effects, and the method mainly comprises the following steps:

(1) The exosome derived from the visceral adipose tissue has a proinflammatory effect in inflammatory bowel diseases, and a fourth department of health care subject of the university of military medical science published in the ACS Nano journal, and research results show that the visceral adipose tissue-derived exosome accelerates the colitis process by transferring proinflammatory miRNA.

(2) Circulating proinflammatory exosomes aggravate stroke in the aging process, and an authoritative periodical Circulation Research journal in the cardiovascular field researches and discovers that blood exosomes of old individuals gradually accumulate peripheral proinflammatory mediators and can pass through a blood brain barrier through a C3aR dependent mechanism to start and excessively activate microglia, so that the occurrence and development of cerebral infarction are promoted.

(3) Exosomes promote tumor-associated inflammatory responses, and the liu provenance topic group of the south beijing medical university published on Cancer Letters: in liver cancer, exosomes from arsenite-transformed L-02 cells increase miR-155 expression and proinflammatory properties of normal L-02 and THLE-3 cells.

(4) The exosome from the renal tubular cells activates fibroblasts to promote renal fibrosis, and the issue group of Chengfan topic in the national hospital of Wuhan university publishes an article in Theransotics journal, and finds that the exosome miR-21 of the renal tubular epithelial cells can activate the fibroblasts in ureter obstructed kidney by targeting miR-21/PTEN/Akt pathway, so that the development of the renal fibrosis is accelerated.

2. The invention successfully extracts the exosome from the fibroreticulocyte through an experiment, and the preparation method of the exosome from the fibroreticulocyte comprises the following steps:

s1, obtaining fibroreticular cells;

the step S1 specifically includes:

collecting adipose tissues, shearing, digesting, screening by a cell sieve, stopping digestion, removing red blood cells and granulocytes by a density gradient centrifugation method, and culturing and subculturing the collected cells by adopting a DMEM complete medium containing FBS to obtain the fibroreticular cells. In the digestion, a mixed enzyme of 0.2 plus or minus 0.02% collagenase, 2.0 plus or minus 0.5mg/ml neutral protease and 0.08 plus or minus 0.01mg/ml hyaluronidase is used for digestion.

And S2, culturing the fibroreticular cells by using a culture medium containing exosome-free serum to obtain a culture medium, then carrying out first solid-liquid separation to obtain a supernatant, carrying out second solid-liquid separation on the supernatant to obtain a solid, and then carrying out heavy suspension to obtain exosomes derived from the fibroreticular cells.

In the above-mentioned step S2, the step,

the first solid-liquid separation was performed using 0.2 μ M filtration.

The second solid-liquid separation comprises: ultracentrifugation is carried out for 60 +/-20 min at the temperature of 4 +/-2 ℃, and the rotating speed of the ultracentrifugation is 1.0 multiplied by 10 ⁵ g±1000g。

The culture medium containing the exosome-free serum contains 0.5-1.5% of P/S, 0.05-0.15% of PB, 45-55 μ M EGF (epidermal growth factor), 0.1-0.3mg/mLFGF (fibroblast growth factor), 50-150nM TGF (transforming growth factor TGF- α), 8-12% of the exosome-free serum DMEM complete medium.

Preferably, the culture medium containing the exosome-free serum contains 1% P/S (penicillin-streptomycin), 0.1% PB (amphotericin B), 50 μ M EGF (epidermal growth factor), 0.2mg/mLFGF (fibroblast growth factor), 100nM TGF (transforming growth factor TGF- α), 10% exosome-free serum DMEM complete medium.

Then, the invention applies the extracted exosome derived from the fibroreticulocyte to the treatment of acute kidney injury caused by mouse sepsis, and experiments show that the exosome derived from the FRCs can play a role in protecting the kidney injury. Therefore, the fibroreticulocyte-derived exosome can be used for preparing a medicament for treating and/or preventing sepsis acute kidney injury.

Optionally, the medicament for treating and/or preventing sepsis acute kidney injury can further comprise pharmaceutically acceptable auxiliary materials and carriers. The adjuvants include at least one of filler, disintegrant, binder, excipient, diluent, lubricant, sweetener or colorant. The dosage form comprises at least one of granule, tablet, pill, capsule, injection or dispersant.

The exosome derived from the fibroreticulocyte is obtained for the first time, and the preparation and extraction steps are different from the conventional extraction scheme, and mainly comprise the following points:

(1) Sources of exosomes: the method is derived from mouse primary fibroreticular cells, is different from the traditional extraction method that the invention uses a plurality of mixed enzymes (adopts the mixed enzyme of 0.2 plus or minus 0.02% collagenase, 2.0 plus or minus 0.5mg/ml neutral protease and 0.08 plus or minus 0.01mg/ml hyaluronidase for digestion), has mild extraction method, small damage to cells, high cell activity and high cell purity of 99.5%, and can still transmit the primary fibroreticular cells extracted by the method to 4-6 generations after being frozen.

(2) Improving the components of a culture medium: the present invention adopts a culture medium containing exosome-free serum as a complete culture medium containing 0.5-1.5% of P/S, 0.05-0.15% of PB, 45-55 μ M EGF (epidermal growth factor), 0.1-0.3mg/mLFGF (fibroblast growth factor), 50-150nM TGF (transforming growth factor TGF- α), 8-12% of exosome-free serum. The improved culture medium has excellent selectivity and is only suitable for the growth of primary fibroreticular cells.

(3) FRC-EXO is applied to acute kidney injury research induced by sepsis for the first time, and compared with interstitial cells, the low immunogenicity, rich fat tissue content and easy amplification characteristics of FRCs make FRCs an ideal method for treating sepsis cells. In the invention, FRCs from fat are successfully separated out, the FRCs are cultured in vitro, exosomes released by the FRCs amplified in vitro are injected into the abdominal cavity of a sepsis AKI mouse, and the treatment effect of the FRCs-exosomes in the fat as a new method on sepsis AKI is discussed.

The results of the study show that administration of FRCs, which lower proinflammatory cytokine levels in serum and at the site of infection by modulating nitric oxide synthase 2 (NOS 2), both early and late in the infection, and exosomes released from FRCs, can reduce sepsis mortality in a Caecum Ligation and Perforation (CLP) -induced sepsis AKI mouse model. A great deal of research is carried out on the treatment effect of FRCs on sepsis, and the results prove that the death rate of sepsis mice can be effectively improved by injecting FRCs into the abdominal cavity, the content of inflammatory factors in blood and abdominal cavity lavage liquid can be reduced, and the bacterial load in the abdominal cavity lavage liquid can be reduced. Further, the fact that the injection of the FRCs-exosome in the abdominal cavity can reduce the serum creatinine and urea nitrogen content of a sepsis mouse and improve the kidney injury degree.

The use of the fibroreticulocyte-derived exosomes of the present application in the preparation of a medicament for treating and/or preventing sepsis acute kidney injury will be described in detail below with reference to examples and experimental data.

Example 1 extraction of exosomes derived from FRCs

1. Primary isolated culture and identification of FRCs

(1) Extracting FRCs of mice: anesthetizing a mouse by using a small animal anesthesia machine (isoflurane) inhalation method, opening the abdominal cavity layer by layer after sterilization, cutting off mesenteric fat, avoiding pancreatic tissue, placing the cut-off adipose tissue in a medium containing 0.2% of collagenase, 2.0mg/ml of neutral protease and 0.08mg/ml of hyaluronidase for digestion for 30-60min, stopping digestion by using the medium containing FBS after cell sieving, removing red blood cells and granulocytes by using a Ficoll density gradient centrifugation method, paving the extracted cells in a T-25 culture bottle by using a DMEM complete medium containing FBS, and culturing in a 5% CO2 incubator at 37 ℃; after 3 days, the nonadherent cells and tissues were discarded, and fresh complete medium was added; when the cells grow to 80% of fusion degree, digesting with 0.25% of pancreatin, carrying out continuous amplification culture in a culture dish of 10cm, recording as the 1 st generation, and then carrying out subculture after liquid change or digestion every three to four days, and recording as one generation every time of passage.

(2) Flow cytometry identification of FRCs: detecting the expression conditions of CD45, PDPN and CD31 on the cell surface of FRCs in the 4 th generation by flow cytometry, wherein a CD45 antibody is used for distinguishing lymphocytes and non-lymphocytes, CD31 is an endothelial cell marker, PDPN is a fibroreticular cell specific marker, and CD45-CD31-PDPN + is an FRCs cell population.

Collecting mesentery adipose tissue of the mouse, wherein the lymph structure in fat is shown in figure 1A, figure 1B shows that the lymph structure in fat is digested by collagenase and is inoculated to a culture dish, and the cell morphology of FRCs is observed in a bright field, so that the cells are in a fusiform shape; detection of FRCs cell surface markers (CD 45) using flow cytometry ^- Podoplanin ⁺ CD31 ^- )，Podoplanin ⁺ CD31 ^- Account for CD45 ^- 99.5% of the cells (FIG. 1C).

2 extracting FRCs exosome and identifying

(1) Extracting FRCs exosomes: FRCs were cultured in exosome-free serum, the supernatant was filtered at 0.2. Mu.M, ultracentrifuged at 4 ℃ for 70 minutes, the supernatant was discarded, and the exosomes were resuspended. And (3) observing the form of the exosome by using a transmission electron microscope, and detecting the size and the diameter of the exosome by using a nano-particle size analyzer.

(2) Exosomes were observed by transmission electron microscopy: a drop of exosomes was suspended in PBS, a Falvar carbon coated nickel mesh was placed on top of the drop with forceps, ensuring that the coating side contained exosomes of shedding, and the morphology of the exosomes was observed with transmission electron microscopy.

(3) Western blot detection of exosome markers: the exosomes were lysed using a protein lysis buffer, and the expression of the target protein was detected by adding antibodies to the exosome transmembrane proteins (CD 9, CD63, HSP70, TSG-101 and CD 81).

(4) Characterization of stem cells of FRCs: and (3) carrying out adipogenic and osteogenic differentiation induction on the FRCs, and identifying the differentiation capacity of the stem cells. Adding an osteogenic differentiation induction culture medium, detecting the expression of osteogenic differentiation marker genes Alp, runx2 and Ocn by qRT-PCR, and detecting the formation condition of an extracellular calcified matrix by alizarin red staining; the adipogenesis induction is similar to the osteogenesis induction, the culture medium is changed into an adipocyte induction culture medium, qRT-PCR detection is carried out on adipogenesis differentiation marker genes Ppar-gamma and Lpl, and oil red O staining is carried out on the intracellular lipid drop formation condition.

As shown in FIG. 2, FIG. 2A shows the morphology of exosomes released from FRCs extracted by ultracentrifugation and observed under an electron microscope, and FIG. 2B shows that exosome-associated marker proteins CD63, CD9, TSG101 and HSP70 were successfully detected by Western blot. The Nanoparticle Tracking Analysis (NTA) technique detects the diameter of the extracted extracellular vesicles, and as can be seen from fig. 2C, 97% of the particles have a diameter of 140.1nm, indicating that the extracellular vesicles are exosomes; to understand the stem cell characteristics of FRCs, adipogenic differentiation of FRCs was induced using adipogenic differentiation medium, and FRCs were differentiated into adipocytes (FIG. 2D).

EXAMPLE 2 use of fibroreticulocyte-derived exosomes in the preparation of a medicament for treating and/or preventing sepsis acute kidney injury

1. Sepsis AKI model induced by Cecal Ligation and Perforation (CLP)

The method for inducing the acute kidney injury model of sepsis by Cecal Ligation and Perforation (CLP) comprises the following steps: selecting 8-12 weeks old C57BL/6 male mice, placing the anesthetized mice in a prone position, opening the abdominal cavity, ligating cecum with 1/4 length, perforating 2 holes at the cecum part by using a 22G needle, squeezing out excrement, closing the abdominal cavity layer by layer, and performing subcutaneous injection by using 20ml/kg normal saline to perform liquid resuscitation. (the methodology is described in Peng ZY, et al, crit Care Med.2012Feb;40 (2): 538-43).

2. FRCs-exosomes capable of homing to the injured kidney

Respectively injecting fluorescence-labeled FRCs-exosomes into the abdominal cavities of sepsis mice, and detecting the distribution condition of the FRCs-exosomes in a plurality of organs (heart, kidney, liver and the like) of the mice by in-vivo imaging of the mice;

the results are shown in fig. 3, the mice which construct the sepsis model through Cecal Ligation and Perforation (CLP) are injected with the fluorescence labeled FRCs in the abdominal cavity, the aggregation positions of the FRCs are observed through living body imaging, the FRCs are aggregated in the abdominal cavity of the mice, and the cell amount of the FRCs is reduced after 48 hours (fig. 3A); collecting peritoneal lavage fluid, spleen and kidney of the three groups of mice, detecting the content of FRCs in different tissues by a flow cytometer, finding that most FRCs still reside in the peritoneal cavity and the FRCs in the kidney are less accumulated, and prompting that the FRCs can influence renal function in a paracrine way (fig. 3B); we further co-cultured the fluorescently-labeled FRCs, FRCs-exosomes with mouse primary tubular epithelial cells, respectively, and found that exosomes were able to be taken up by tubular epithelial cells (fig. 3C).

3. Protective effect of FRCs-exosomes on sepsis AKI

Improvement of AKI by administration of FRCs-exosomes: injecting FRCs-exosomes into sepsis AKI mice, and observing the survival rate of the sepsis AKI mice for one week and the kidney function to determine the improvement effect of the FRCs-exosomes on the survival rate of the sepsis AKI.

Protection of FRCs-exosomes against sepsis AKI: injecting FRCs or FRCs-exosomes into the abdominal cavity of a CLP sepsis mouse, collecting a kidney tissue, a serum sample and a urine sample after 24 hours, determining the levels of serum creatinine and urea nitrogen in the blood serum of the mouse by using a creatinine and urea nitrogen detection kit (the markers of kidney injury mainly comprise creatinine and urea nitrogen), performing HE (hematoxylin-eosin) staining on the kidney tissue, and evaluating the severity of the kidney injury according to a kidney injury score scale;

results as shown in fig. 4, we further extracted FRCs from mice, and exosomes released from FRCs, injected FRCs and FRCs-exosomes into the abdominal cavity of septic mice 1 hour after sepsis, and observed the survival rate of septic mice for 120 h. As can be seen from FIG. 4A, the median survival time of the mice in the CLP group is 36 hours, the median survival time of the CLP + FRCs-exosomes is 72 hours, and the survival rate of the sepsis mice can be obviously improved by injecting the FRCs-exosomes into the abdominal cavity (P is less than 0.05); as can be seen from FIG. 4B, the serum creatinine content of the mice was detected, and it was found that the serum creatinine of the mice was significantly reduced 24 hours after injection of FRCs and FRCs exosomes.

4. FRCs-exosomes improved LPS induced sepsis AKI

Pretreating mouse renal tubular epithelial cells by using LPS, co-culturing FRCs-exosomes and the renal tubular epithelial cells, detecting renal tubular epithelial cell apoptosis protein, and detecting the expression conditions of NOD-like receptor protein 3 inflammation body (NLRP 3), inflammatory CASPASE-mediated key substrate protein GSDMD, apoptosis protein CASPASE-1 and internal reference GAPDH of cell apoptosis.

The results are shown in fig. 5, it can be seen that FRC-exosomes are added to the NC group and the LPS group respectively, under the induction of LPS, the contents of NLRP3 and caspase-1 proteins in primary tubular epithelial cells of mice are significantly increased, which indicates that inflammatory bodies are formed, and then GSDMD proteins perforate cell membranes, cytoplasm outflows, and inflammatory factors are released, and FRCs-exosomes are further added to tubular epithelial cells of mice in which the LPS stimulates AKI, the contents of inflammation-related NLRP3 and caspase-1 are significantly reduced, the expression level of GSDMD proteins is equivalent to that of the NC group, cells are restored to the pre-injury level, which indicates that FRCs-exosomes improve LPS-induced sepsis AKI.

In conclusion, the exosomes derived from the FRCs can play a role in protecting renal injury, promote the injury repair of injured renal tubular cells, promote the proliferation of the injured renal tubular cells, reduce the renal tubular necrosis, relieve the inflammatory reaction and reduce the oxidative stress. The traditional Chinese medicine composition is applied to the treatment of acute kidney injury of mouse sepsis, and achieves a good treatment effect. Compared with the traditional cell therapy, the exosome has the characteristics of good stability and convenience and quickness in storage and application. The exosome is used as a non-cell biological agent, overcomes the limitation of cell therapy, has the advantages of difficult tumorigenesis, low antigenicity, strong targeting property and the like, and has huge clinical application potential.

Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. Application of fibroreticulocyte-derived exosomes in preparation of medicines for treating and/or preventing sepsis acute kidney injury.

2. The use according to claim 1, wherein said fibroreticulocyte-derived exosomes are prepared by a method comprising:

obtaining fibroreticular cells;

culturing the fibroreticular cells by using a culture medium containing serum without exosomes to obtain cell supernatant, then carrying out first solid-liquid separation to obtain supernatant, carrying out second solid-liquid separation on the supernatant to obtain solids, and then carrying out heavy suspension to obtain exosomes derived from the fibroreticular cells.

3. The use of claim 2, wherein said obtaining fibroreticulocytes comprises:

4. The use according to claim 3, wherein in the digestion, a mixture of 0.2 + 0.02% collagenase, 2.0 + 0.5mg/ml neutral protease and 0.08 + 0.01mg/ml hyaluronidase is used for digestion.

5. Use according to claim 2, wherein the first solid-liquid separation is performed using 0.2 μ M filtration.

6. Use according to claim 2, wherein the second solid-liquid separation comprises: ultracentrifugation is carried out for 60 plus or minus 20min at the temperature of 4 plus or minus 2 ℃, and the rotating speed of the ultracentrifugation is 1.0 multiplied by 10 ⁵ g±1000g。

7. The use according to claim 2, wherein the exosome-free serum-containing medium is a DMEM complete medium containing 0.5-1.5% p/S, 0.05-0.15% pb, 45-55 μ M EGF, 0.1-0.3 mg/mfgf, 50-150nM TGF, 8-12% exosome-free serum.

8. The use according to claim 2, wherein the marker antibodies of the fibroreticulocyte are CD45 ", PDPN + and CD 31".

9. Use according to claim 2, wherein the fibroreticulocyte-derived exosome-specific markers are CD9, CD63, HSP70, TSG-101 and CD81.

10. A medicament for the treatment and/or prevention of sepsis acute kidney injury, comprising fibroreticulocyte-derived exosomes.