PURPOSE: The incidence of acute lung injury (ALI) in severe trauma patients is 48% and the mortality rate following acute respiratory distress syndrome evolved from ALI is up to 68.5%. Alveolar epithelial type 1 cells (AEC1s) and type 2 cells (AEC2s) are the key cells in the repair of injured lungs as well as fetal lung development. Therefore, the purification and culture of AEC1s and AEC2s play an important role in the research of repair and regeneration of lung tissue. METHODS: Sprague-Dawley rats (3-4 weeks, 120-150 g) were purchased for experiment. Dispase and DNase I were jointly used to digest lung tissue to obtain a single-cell suspension of whole lung cells, and then magnetic bead cell sorting was performed to isolate T1α positive cells as AEC1s from the single-cell suspension by using polyclonal rabbit anti-T1a (a specific AEC1s membrane protein) antibodies combined with anti-rabbit IgG microbeads. Afterwards, alveolar epithelial cell membrane marker protein EpCAM was designed as a key label to sort AEC2s from the remaining T1α-neg cells by another positive immunomagnetic selection using monoclonal mouse anti-EpCAM antibodies and anti-mouse IgG microbeads. Cell purity was identified by immunofluorescence staining and flow cytometry. RESULTS: The purity of AEC1s and AEC2s was 88.3% ± 3.8% and 92.6% ± 2.7%, respectively. The cell growth was observed as follows: AEC1s stretched within the 12-16 h, but the cells proliferated slowly; while AEC2s began to stretch after 24 h and proliferated rapidly from the 2nd day and began to differentiate after 3 days. CONCLUSION AEC1s and AEC2s sorted by this method have high purity and good viability. Therefore, our method provides a new approach for the isolation and culture of AEC1s and AEC2s as well as a new strategy for the research of lung repair and regeneration.
Alveolar Epithelial Cells/cytology* ; Animals ; Cell Culture Techniques ; Cell Separation/methods* ; Immunoglobulin G/metabolism* ; Lung ; Magnetic Phenomena ; Rats ; Rats, Sprague-Dawley

In this study, we improved the culture method of mouse hippocampal primary microglia to obtain hippocampal ramified microglia with high activity and purity, which were resemble to the resting status of normal microglia in healthy brain in vivo. Hippocampal tissue was excised from 2-4-week-old SPF C57BL/6J mice and cut into pieces after PBS perfusion, and then manually dissociated into the single-cell suspension by using Miltenyi Biotec's Adult Brain Dissociation Kit. The tissue fragments such as myelin in the supernatant were removed by debris removal solution in the kit. The cell suspension was incubated with CD11b immunomagnetic beads for 15 min at 4 °C. To obtain high-purity microglia, we used two consecutive cell-sorting steps by magnetic activated cell sorting (MACS). After centrifugation, the cells were resuspended and seeded in a 24-well culture plate. The primary microglia were cultured with complete medium (CM) or TIC medium (a serum-free medium with TGF-β, IL-34 and cholesterol as the main nutritional components) for 4 days, and then were used for further experiments. The results showed that: (1) The cell viability was (56.03 ± 2.10)% by manual dissociation of hippocampus; (2) Compared with immunopanning, two-step MACS sorting allowed for efficient enrichment of microglia with higher purity of (86.20 ± 0.68)%; (3) After being incubated in TIC medium for 4 d, microglia exhibited branching, quiescent morphology; (4) The results from qRT-PCR assay showed that the levels of TNF-α, IL-1β and CCL2 mRNA in TIC cultured-microglia were similar to freshly isolated microglia, while those were much higher in CM cultured-microglia after incubation for 4 d and 7 d (P < 0.05). Taken together, compared to the conventional approaches, this modified protocol of mouse hippocampal primary microglia culture by using MACS and TIC medium enables the increased yield and purity of microglia in the quiescent state, which is similar to normal ramified microglia in healthy brain in vivo.
Animals ; Cell Culture Techniques ; methods ; Cell Separation ; methods ; Cells, Cultured ; Hippocampus ; Magnetics ; Mice ; Mice, Inbred C57BL ; Microglia ; cytology

Research on CellSearch system's detection rate of cells and linearity performance detection method, so as to analyze the accurate and reasonable detection method to meet the CellSearch characteristics of the system.
Biomarkers, Tumor ; Cell Line, Tumor ; Cell Separation ; methods ; Humans ; Neoplastic Cells, Circulating

Objective To develop an improved method for culturing Schwann cells(SCs) by using both enzyme digestion and explants-culture approaches and compared with traditional explants-culture method and general hemi-explants-culture method. Methods Bilaterally sciatic nerves and brachial plexus nerves were dissected from 3 to 5-day-old neonatal SD rats and explants-culture method,general hemi-explants-culture method,and improved enzyme digestion combined with explants-culture method were adopted to culture SCs,respectively. SCs were digested and passaged after 7 days in culture and counted under the microscope. The purity of SCs was identified by S-100 immunofluorescence staining. Results The SCs of improved method group grew fastest and the total number of cells obtained was(1.85±0.13)×10(6);the SCs of the hemi-explants-culture method group grew slower than the improved method group and the total number of cells obtained was (1.10±0.10)×10(6);the SCs of the explants-culture method group grew slowest and the total number of cells obtained was (0.77±0.03)×10(6).The total number of cells obtained showed significant difference among the three groups(P<0.01). Immunofluorescence staining showed that the SCs purity was (95.73±1.51)% in the improved method group,(84.66±2.68)% in the hemi-explants-culture method group,and (74.50±4.23)% in the explants-culture method group(P<0.01). Conclusion The improved enzyme digestion combined with explants-culture method can obtain sufficient amount of high-purity SCs in a short time and thus may be applied in further research on peripheral nerve regeneration.
Animals ; Animals, Newborn ; Brachial Plexus ; cytology ; Cell Culture Techniques ; Cell Separation ; methods ; Cells, Cultured ; Enzymes ; Rats ; Rats, Sprague-Dawley ; Schwann Cells ; cytology ; Sciatic Nerve ; cytology

The death of patients with gastric cancer is mainly due to its recurrence and metastasis, and circulating tumor cell (CTC) is the necessary condition of metastasis. As liquid biopsy, CTC detection has its certain clinical significance. The detection is required after enrichment because circulating tumor cells are rare. Many enrichment methods have been developed: methods based on physical characteristics of TCT, like density, size and dielectric properties and so on; immunogenicity, like Cell Search System; and microfluidic chip technology. The immunofluorescence is commonly used to identify CTC in gastric cancer and the isolated CTC can also be used for the following analysis on the level of nucleic acid, protein and gene regulation. Detection of CTC in gastric cancer is helpful to judge the prognosis, assess staging, monitor the curative effect and guide the development of drug. There are many challenges for clinical transformation of CTC: the lower enrichment efficiency, the less specific surface markers, the uncertain diagnostic efficiency and so on, but it also has the good research prospect because it is non-invasive, repeatable and can real-time monitor the condition and guide the clinical treatment compared with pathological biopsy. In this paper, the detection and identification methods, and clinical value of CTC in gastric cancer patients are reviewed.
Biomarkers, Tumor ; Biopsy ; Cell Separation ; methods ; Cytodiagnosis ; methods ; Flow Cytometry ; methods ; Fluorescent Antibody Technique ; methods ; Humans ; Microchip Analytical Procedures ; methods ; Neoplasm Recurrence, Local ; prevention & control ; Neoplasm Staging ; methods ; Neoplastic Cells, Circulating ; metabolism ; pathology ; Prognosis ; Secondary Prevention ; Stomach Neoplasms ; blood ; diagnosis ; genetics ; therapy ; Treatment Outcome

Adipose-derived stem cells (ADSCs) are an attractive source of material for mesenchymal stem cell research due to the abundance of adipose and relative ease of access compared with bone marrow. A key consideration for research is whether cell isolation methods can be improved, to reduce the process steps needed to isolate and expand cell material. In the current study, we used macroporous biopolymer microcarriers to isolate primary ADSCs. We found that the method was capable of isolating ADSCs that were subsequently capable of being transferred to culture dishes and expanded in vitro. Moreover, flow cytometry revealed that they expressed typical stem cell markers and were capable of undergoing tri-lineage differentiation. In summary, it is feasible to use biopolymer microcarriers for retrieval of viable ADSCs that retain identity markers of stem cell function.
Adult Stem Cells ; Animals ; Biopolymers* ; Bone Marrow ; Cell Separation ; Flow Cytometry ; In Vitro Techniques ; Mesenchymal Stromal Cells ; Methods ; Rats* ; Stem Cells*

OBJECTIVETo optimize the methods of isolating human eccrine sweat gland cells in vitro so as to get efficiently primary human sweat glands.

METHODSThe fresh and normal skin tissue was cut into pieces of microskin about 1mm3 and the following 3 group digestion buffer was applied to isolated gland cells. The digestion buffer of group A was the equivoluminal mixture of Trypsin-Ethylene Diamine Tetraacetic Acid (EDTA) and collagenase-II (2 mg/ml). The digestion buffer of group B was collagenase-II (2 mg/ml) traditionally and group C was Trypsin-EDTA. These three groups were placed into an incubator simultaneously and the emerging time of dissociated sweat glands was calculated. Sweat glands were sorted out and then placed in culture dish. The adherence and the growth of cells were observed. The proliferation index was detected by flow cytometry. The identification of cultured cells was performed by immunocytochemical staining.

RESULTSAfter digesting 30 min in group A and C, a very few of dissociated sweat glands were emerging. But after digesting for 2 h, there were lots of dissociated sweat glands emerging in group A rather than in group C. The emergence of dissociated sweat glands in group B would require at least 6 hours. After seeded in culture dishes, the sweat glands in group C couldn't adhere to the wall of dish, but the sweat glands in group A and B adhered very well and even grew like paving stones after 9 days. In addition, the proliferation index were (18 ± 4) % and (17 ± 6) % respectively, there was no statistical difference. The results of immunocytochemical staining showed that the cells expressed carcino-embryonic antigen (CEA) and cytokeratin 7(CK7) in group A and B.

CONCLUSIONTrypsin-EDTA combined with collagenase-II can shorten the time of isolating sweat gland cells and have no effect on cell activity and proliferation.

To improve a fast and high-quality isolation method for culturing the primary cardiomyocyte and fibroblast in vitro, the neonatal Wistar rats were decapitated accordingly and left ventricles were isolated under the sterile condition. The ventricles were chopped and digested in the enzyme solution containing 0.5 mg/mL type II collagenase. During this process, the digesting time, frequency and stirring speed, centrifuging frequency and speed were strictly controlled. The cardiomyocytes were separated from the cardiac fibroblast by using the Percoll density gradient centrifugation. The cell viability was tested by staining with 0.2% trypan blue. The purity of cardiomyocytes and fibroblasts were determined by immunoflourescent staining with anti-cTnI, anti-Vimentin and anti-α-SMA antibodies. The results indicated that with this protocol, the viability and purity of cardiomyocytes were 92% and 95%. The automobile pulse of the adhered cardiomyocyte was visible. For fibroblasts, the cell viability and purity were 96% and 94%. Our results demonstrate that this advanced isolation method is reproducible, and can simultaneously produce high-quality primary cardiomyocytes and fibroblasts for the future study.
Animals ; Cell Separation ; methods ; Cell Survival ; Centrifugation, Density Gradient ; Fibroblasts ; Heart Ventricles ; cytology ; Myocytes, Cardiac ; Povidone ; Rats ; Rats, Wistar ; Silicon Dioxide

The aim of the present study was to observe the effect of trypsin digestion on the purity of in vitro cultured astrocytes and optimize the culture methods. The cerebral cortical tissue from newborn Sprague Dawley (SD) rats was isolated and digested with 0.25% trypsin for 20, 30, or 40 min. The obtained single cell suspension was then cultured. Once reaching confluence, the cells were shaken at a constant temperature. Then, each of 20 and 30 min groups was subdivided into two groups, the control group with normal digestion and two-time-digestion group, and the cells were passaged and purified. Through inverted phase contrast microscope and MTT assay, cell growth and proliferation were observed, respectively. Immunofluorescence for glial fibrillary acidic protein (GFAP) was used to observe the morphology of astrocytes and to assess their purity in different stages. Flow cytometric analysis was used to detect the apoptotic rates of purified astrocytes. The results showed that, the cells being digested for 20 min usually reached confluence at 9 d after seeding. When the digestion time was extended to 30 min, the cells grew faster and reached confluence at 7 d after seeding, meanwhile the morphology of astrocytes was normal, GFAP positive rate (70.2 ± 4.0)% being much higher than that of the 20 min group (P < 0.05). Compared with 20 min group, 40 min group showed higher GFAP positive rate, whereas the cell proliferation was slower, and cell injury was more obvious. After shaking at constant temperature, two times of trypsin digestion could decrease the number of contaminated cells after passage. The GFAP positive rates of two-time-digestion groups in passage 1 (P1) were higher than those of corresponding control groups, and the GFAP positive rate of 30 min + two-time-digestion group in P1 reached (98.1 ± 1.7)%, which was equivalent to that of the 20 min + control group in P3. However, the apoptotic rate showed no significant difference between these two groups. Based on above mentioned results, we conclude that 30 min + two-time of trypsin digestion effectively improves the purity of astrocytes and shortens the time of primary culture and purification, suggesting that it is a rapid and effective method to obtain astrocytes with high purity in vitro.
Animals ; Astrocytes ; cytology ; Cell Culture Techniques ; Cell Proliferation ; Cell Separation ; methods ; Glial Fibrillary Acidic Protein ; metabolism ; Rats ; Rats, Sprague-Dawley ; Trypsin

Mesenchymal stem cell (MSC)-mediated therapy has been shown to be clinically effective in regenerating tissue defects. For improved regenerative therapy, it is critical to isolate homogenous populations of MSCs with high capacity to differentiate into appropriate tissues. The utilization of stem cell surface antigens provides a means to identify MSCs from various tissues. However, few surface markers that consistently isolate highly regenerative MSCs have been validated, making it challenging for routine clinical applications and making it all the more imperative to identify reliable surface markers. In this study, we used three surface marker combinations: CD51/CD140α, CD271, and STRO-1/CD146 for the isolation of homogenous populations of dental mesenchymal stem cells (DMSCs) from heterogeneous periodontal ligament cells (PDLCs). Fluorescence-activated cell sorting analysis revealed that 24% of PDLCs were CD51(+)/CD140α(+), 0.8% were CD271(+), and 2.4% were STRO-1(+)/CD146(+). Sorted cell populations were further assessed for their multipotent properties by inducing osteogenic and chondrogenic differentiation. All three subsets of isolated DMSCs exhibited differentiation capacity into osteogenic and chondrogenic lineages but with varying degrees. CD271(+) DMSCs demonstrated the greatest osteogenic potential with strong induction of osteogenic markers such as DLX5, RUNX2, and BGLAP. Our study provides evidence that surface marker combinations used in this study are sufficient markers for the isolation of DMSCs from PDLCs. These results provide important insight into using specific surface markers for identifying homogenous populations of DMSCs for their improved utilization in regenerative medicine.
Adaptor Proteins, Signal Transducing ; analysis ; Adult ; Aggrecans ; analysis ; Antigens, CD ; analysis ; Antigens, Surface ; analysis ; CD146 Antigen ; analysis ; Cell Differentiation ; physiology ; Cell Lineage ; Cell Separation ; methods ; Cells, Cultured ; Chondrogenesis ; physiology ; Collagen Type II ; analysis ; Core Binding Factor Alpha 1 Subunit ; analysis ; Flow Cytometry ; methods ; Homeodomain Proteins ; analysis ; Humans ; Integrin alphaV ; analysis ; Mesenchymal Stromal Cells ; cytology ; physiology ; Multipotent Stem Cells ; cytology ; physiology ; Nerve Tissue Proteins ; analysis ; Osteogenesis ; physiology ; Periodontal Ligament ; cytology ; Receptor, Platelet-Derived Growth Factor alpha ; analysis ; Receptors, Nerve Growth Factor ; analysis ; SOX9 Transcription Factor ; analysis ; Time Factors ; Transcription Factors ; analysis