Advanced tumor electric fields therapy: A review of innovative research and development and prospect of application in glioblastoma

Abstract Background Glioblastoma multiforme (GBM) is an aggressive malignant tumor with a high mortality rate and is the most prevalent primary intracranial tumor that remains incurable. The current standard treatment, which involves surgery along with concurrent radiotherapy and chemotherapy, only yields a survival time of 14–16 months. However, the introduction of tumor electric fields therapy (TEFT) has provided a glimmer of hope for patients with newly diagnosed and recurrent GBM, as it has been shown to extend the median survival time to 20 months. The combination of TEFT and other advanced therapies is a promising trend in the field of GBM, facilitated by advancements in medical technology. Aims In this review, we provide a concise overview of the mechanism and efficacy of TEFT. In addition, we mainly discussed the innovation of TEFT and our proposed blueprint for TEFT implementation. Conclusion Tumor electric fields therapy is an effective and highly promising treatment modality for GBM. The full therapeutic potential of TEFT can be exploited by combined with other innovative technologies and treatments.

TMZ. 4 TMZ resistance is a significant factor contributing to a negative prognosis in patients. 4Radiotherapy has been associated with the development of radiation-induced brain injury, which includes cognitive dysfunction and increased intracranial pressure. 5,6In cases of recurrent GBM, the median overall survival (OS) is typically limited to 3-5 months without the implementation of effective therapeutic interventions. 7Consequently, the investigation of an anticancer treatment modality that is both efficacious and well tolerated is crucial for enhancing the survival rates of individuals diagnosed with GBM.
Tumor electric fields therapy (TEFT) is a biophysical technology that inhibits the growth of proliferating cells, including cancer cells, while sparing nonproliferating cells when applied under appropriate conditions. 8Dr.Ling Chen's team, along with other researchers, has demonstrated that TEFT, which utilizes alternating electric fields of low intensity (1-3 V/cm) and intermediate frequency (100-300 kHz), induces cell death in a wide range of tumor cells both in vitro and in vivo [9][10][11] while having minimal impact on normal cells. 8It has been observed that most types of GBM cells exhibit optimal response at a frequency of 200 kHz, with only a few cell types showing no response at this frequency. 11The effectiveness of TEFT on cellular processes such as cell division and cell death was found to be influenced by the intensity of the applied electric field and the angle between the electric field and the axis of division. 9As a form of physical treatment therapy, TEFT demonstrated a favorable safety profile with minimal adverse reactions, primarily limited to skin-related adverse events. 9,12,13A clinical trial involving 10 patients with recurrent GBM treated with TEFT revealed a median OS of 62.2 weeks.Based on these findings, TEFT received approval in the United States and Europe for the treatment of recurrent GBM and is now recommended as a first-line therapy following surgical resection, radiotherapy, and TMZ.A more extensive clinical trial of EF-14, which encompassed 695 patients, revealed that the median OS was 20.9 months in the TEFT plus TMZ group, whereas it was 16.0 months in the TMZ alone group.Additionally, the median progression-free survival (PFS) was observed to be 6.7 months in the TEFT plus TMZ group, compared to 4.0 months in the TMZ group. 14Notably, for Chinese patients, the median PFS was 16 months in the TEFT plus TMZ group, in contrast to 11 months in the TMZ group.Similarly, the median OS for Chinese patients was 21.8 months in the TEFT plus TMZ group, while it was 15 months in the TMZ group. 15It is worth mentioning that the TEFT instruments were granted approval by the Chinese National Medical Products Administration in 2020.
Despite the significant improvement in the prognosis of patients with GBM through the use of TEFT, there remains a limited understanding of the molecular mechanisms underlying TEFT action.Furthermore, it is crucial to optimize and upgrade the current hardware and software to enhance the efficacy of TEFT.Consequently, this article aims to summarize the recently proposed mechanisms by which TEFT induces antitumor effects and to discuss the prospects of optimizing TEFT instruments.

| MECHANIS M OF TEF T
The mechanisms underlying tumor cytotoxicity can be categorized into several perspectives, including apoptosis, autophagy, cell cycle arrest, anti-angiogenesis, enhanced drug penetration, reduced DNA repair capacity, diminished migration and invasion capabilities, and immune activation. 13,16Preclinical studies have shown multiple effects on GBM cells, including promoting cell death, inhibiting DNA repair, inhibiting proliferation, and regulating immune response.
TEFT treatment results in the extension of mitosis in the majority of treated GBM cells, resulting in the cessation of proliferation.
Additionally, approximately 25% of GBM cells undergoing mitosis experience destruction due to cell membrane rupture, while nuclear rotation is observed in a subset of cells. 8

| TEFT promoting several types of cell death
The primary mechanism employed in the application of TEFT involved anti-mitotic effects, such as the induction of prolonged mitosis, aberrant mitotic morphology, and mitotic cell death. 16,17The principal function of the mitotic spindle is to accurately segregate the chromosomes to opposing poles of the cells. 18TEFT has been found to impair chromosomal segregation and cell division through two major mechanisms, as summarized in several reviews.These mechanisms include the disruption of mitotic spindle microtubule formation and the dielectrophoretic effect. 19,20Specifically, TEFT hinders the localization of cytokinetic cleavage furrow to the midline of the spindle by affecting Septin, resulting in plasma membrane instability and blebbing, ultimately leading to abnormal cytokinesis in the telophase stage. 21,22Additionally, TEFT perturbs spindle microtubules and normal spindle assembly during mitosis, thereby preventing complete cytoplasmic separation. 10optosis has traditionally been regarded as the sole form of controlled cell death, characterized by the disintegration of the nuclear membrane, cleavage of intracellular proteins, membrane blebbing, and the degradation of genomic DNA into nucleosomal structures. 23The induction of apoptotic cells by TEFT was found to be notably mediated by caspase-3 activation and Poly (ADP-ribose) Polymerase (PARP)-1 cleavage, in a p53-dependent manner. 24,25tophagy serves a dual function in the progression of tumors, as it promotes both tumor survival and growth by overcoming stressful conditions, while also suppressing tumor growth through the maintenance of cellular homeostasis at a basal level of autophagy. 26In consistency, the specific impact of autophagy in combinatorial therapy with TEFT remains unclear, as it is uncertain whether autophagy enhances or reduces the killing of GBM cells. 16It has been established that TEFT leads to mitotic arrest, which is associated with increased activation of autophagy. 27The induction of autophagic cell death by TEFT occurs through the miR-29b-Akt2 pathway, with downstream effects on the mammalian target of rapamycin (mTOR)/ribosomal | 3 of 14 protein S6 kinase (S6K)/eukaryotic translation initiation factor 4E binding protein 1 (4EBP1) axis. 25TEFT was found to enhance autophagic flux through the upregulation of proteotoxic stress response and the activation of AMP-activated protein kinase (AMPK) and sequential unc-51-like autophagy-activating kinase 1 (ULK1). 28

| TEFT inhibits DNA repair
Additionally, TEFT demonstrated inhibitory effects on DNA repair, as it suppressed the DNA damage response following exposure to radiotherapy, 29 suggesting that a combination of radiotherapy and TEFT may be beneficial in controlling the progression of GBM.The breast cancer susceptibility gene 1 (BRCA1) gene, which plays a crucial role in DNA damage response, including repair of double-strand DNA breaks and stalled fork repair.1][32] The inhibition of the BRCA1 pathway was observed following exposure to TEFT. 33An increase in replication protein A (RPA), which serves as a marker for replication stress and protects single-stranded DNA at stalled replication forks, was detected after TEFT exposure. 30These findings suggest that TEFT leads to an elevated level of DNA damage and a decrease in the capacity for repair through multiple pathways. 16

| TEFT inhibits cell proliferation and migration
TEFT suppressed GBM cell proliferation by reducing circMMD synthesis, thereby inhibiting the Wnt/β-catenin pathway. 34Kirson et al. demonstrated that TEFT had the potential ability to inhibit the migration of tumor metastasis and activate antitumor immune response in peri-tumoral location. 35Additionally, TEFT was found to impair the migration and invasion of GBM cells. 36Yoon et al. demonstrated that TEFT exerts inhibitory effects on cell migration and invasion by downregulating of phosphoinositide 3-kinase (PI3K)/AKT/ nuclear factor-κB (NF-κB) signaling pathway. 37
In the TEFT-treated mouse model, there was a decrease in exhausted CD8+ T cells and an increase in the formation of memory T cells. 45Furthermore, patients who received TEFT treatment exhibited clonal expansion of T cells in their blood, indicating a robust tumor-specific immune response. 45Positive T cell-mediated responses were observed in TEFT-treated tumor areas, as evidenced by CD45 activation and subsequent tumor necrosis factor (TNF)α production to induce cell death. 35,46T-lymphocyte counts have been identified as a prognostic indicator for treatment outcomes in the context of TEFT. 47Additionally, TEFT treatment has been shown to recruit dendritic cells (DCs) from the bone marrow, enhance the ability of bone marrow-derived DCs to engulf cancer cells, and facilitate the maturation of DCs by upregulating MHC class II molecules, CD40, and CD80. 48Furthermore, TEFT has been found to elevate the levels of pro-inflammatory cytokines, including interleukin (IL)-1β, TNFα, and IL-6, in macrophages through the regulation of the mitogen-activated protein kinase (MAPK) and NF-κB signaling pathway. 48,49Moreover, TEFT-treated macrophages have exhibited increased production of nitric oxide and reactive oxygen species (ROS), which have been shown to effectively eliminate tumor cells and pathogens. 49e to the presence of the blood-brain barrier (BBB), the transport of activated immune cells from blood to the brain parenchyma was strictly restricted. 50TEFT increases the permeability of BBB, 51,52 which is an advantage factor for immune cells to access the brain parenchyma.
As mentioned above, TEFT has a powerful impact on promoting antitumor immunity to invert the immune-suppressive environment.Furthermore, the promotion of immunogenic cell death (ICD) by TEFT emerged as a significant concern. 53ICD causes the liberation of specific molecules to activate immune response, 54 which improves tumor immunogenicity.
TEFT induced ICD, characterized by the translocation calreticulin (CRT) to the cell surface, the release of the alarmin highmobility group box 1 (HMGB1), and the secretion of adenosine triphosphate (ATP). 44Voloshin et al. demonstrated that TEFT induced ICD via influencing the biological behavior of immune cells, such as the maturation of DCs in vitro and leukocyte recruitment in vivo. 44TEFT was found to activate the GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) inflammasomes and absent in melanoma 2 (AIM2)/caspase-1 inflammasomes, resulting in the production of pro-inflammatory cytokines (PICs) and type 1 interferon (T1IFNs), which induced adaptive immunity against GBM. 55e findings indicated that TEFT effectively inhibited the growth of GBM cells through a complex interplay of multiple factors, as depicted in Figure 1.While much research has focused on TEFT's role in mitotic arrest and cell death, further investigation is warranted to elucidate its mechanisms in stimulating immune activities.

| EFFIC AC Y OF TEF T
TEFT was employed to generate an alternating electric field using transducer arrays directly applied to the scalp of patients. 36The frequency range of TEFT, spanning from 10 kHz to 1 MHz, was carefully selected to prevent the stimulation of excitable tissues such as nerves and muscles. 36,56It should be noted that high-frequency fields exceeding 500 kHz were found to induce tissue heating via the vibration of charged and/or polar molecules. 16,57In a study conducted by Kirson et al., it was demonstrated that TEFT within the frequency range of 100-300 kHz effectively inhibited the growth of GBM cells both in vitro and in vivo. 8Consequently, these intermediate-frequency alternating electric fields (100-300 kHz) were deemed to be efficacious without causing any adverse tissue effects.
The maximal inhibition of TEFT was found to be contingent upon the specific frequency of alternating electric fields, varying according to cell types. 8In the clinical therapy of GBM cells, a frequency of 200 kHz has been employed. 9Kseeler et al. proved that the frequency of 200 kHz had the maximum effect on four GBM cell lines (GaMG, U-138MG, U-343 MG, and U-87 MG) proliferation among frequencies of 100, 200, 300, and 400 kHz. 58It should be noted that different patients with GBM displayed distinct characteristics, resulting in varying sensitive frequencies.Our research team has observed that the majority of cell lines exhibited sensitivity to a frequency of 200 kHz.
However, the specific sensitive frequency varied for each cell line, and the therapeutic effect was enhanced by the random sequential sequence of TEFT.Furthermore, increasing the random sequential directions demonstrated improved efficacy in inhibiting tumor growth. 11sed on this result, Dr. Ling Chen's team developed a new type of TEFT equipment system named ASCLU-300 which offers adjustable frequency and intensity along with random sequential direction. 59Dr. Ling Chen's team also upgraded the second generation of an instrument named ASCLU-350 (Hunan An Tai Kang Cheng Biotechnology Co., Ltd.) (Figure 2), and we conducted a prospective, single-center, single-arm, exploratory study (NCT0441793). 60,61I G U R E 1 The mechanism of TEFT.TEFT inhibited GBM progression by disturbing mitosis, promoting apoptosis, triggering immune response, inhibiting DNA repair, and restraining cell proliferation and migration (By Figdraw).

5-aminolevulinic acid hydrochloride was approved for use as an
optical imaging agent in the context of neurosurgery for glioma resection to demarcate the relative boundary of malignant tissue and normal tissue. 62Exposure to TEFT resulted in heightened uptake of 5-aminolevulinic acid, with this increase being directly proportional to the duration of exposure, owing to the augmented permeability of cellular membranes. 635-aminolevulinic acid proved to be a reliable indicator for assessing the permeability of glioma cells, including GBM cells.Furthermore, TEFT significantly amplified both the quantity and size of cell membrane perforations, as observed through scanning electron microscopy. 63The efficacy of cooperative reinforcement between TEFT and chemotherapy might be implemented by TEFT improving the concentration of chemotherapeutic drugs within tumor cells.However, other studies have demonstrated that TEFT not only reduces the viability of multi-drug resistant cells but also improves chemotherapy efficacy without impacting drug transport. 64These findings consistently indicate that TEFT increases the permeability of GBM cell membranes, thereby enhancing sensitivity to chemotherapy.
TEFT-based combination therapies show promising potential for the treatment of GBM in the future.Here, we provide a comprehensive overview of preclinical research and clinical trials investigating the combination of TEFT with various treatment modalities, including chemotherapy, radiotherapy, concurrent chemoradiotherapy, targeted therapy, immunotherapy, small molecular inhibitors, tumor vaccine, skull remodeling surgery, and multiple-treatment approaches (Table 1).

Stupp et al. reported that compared to active chemotherapy,
the median survival of TEFT application alone only prolonged 0.6 months, and the difference was not significant (p = 0.27). 7The result meant the curative effect of TEFT was equivalent to chemotherapy, and the combination of those two entirely different therapies might be quite effective.A phase 3 (EF-11) randomized clinical trial in 695 newly diagnosed GBM patients concluded that combination therapy with TEFT and chemotherapy was more effective than chemotherapy alone (median OS of 20.9 months vs. 16.0 months). 14A second phase 3 (EF-14) randomized clinical trial for newly diagnosed GBM revealed that the combination of TEFT (≥ 18 h/d) and TMZ maintenance therapy significantly prolonged the OS with 4.9 months compared to TMZ alone group (20.9 months vs. 16 months). 14The median time of this trial from diagnosis to randomization was 3.8 months in the combination of TEFT plus TMZ group and 3.7 months for TMZ alone group.
Accordingly, the median OS for the patients receiving TEFT plus TMZ was 24.7 months from the diagnosis. 65m et al. found that radiotherapy enhanced cellular response as TEFT was administrated prior to radiotherapy. 24In contrast, delaying TEFT application after radiotherapy also increased treatment efficacy, and the combination of TEFT and radiotherapy showed no increase in skin toxicities. 29

TA B L E 1 (Continued)
of TEFT or anti-PD-1.This was accompanied by an increase in macrophages, DCs infiltration, and interferon (IFN)γ production in vivo. 44Although the experiment was conducted on mice with lung carcinoma and the inhibitory effect of combination therapy on tumor growth did not reach statistical significance, the findings demonstrated the safety of combination therapy and indicated a potential for inhibiting tumor growth.These results hold valuable implications for GBM research.

| ADVANTAG E S OF TEF T
Chemotherapy is commonly used as an adjunctive treatment for post-resection GBM.However, the efficacy of chemotherapy is hindered by the limited permeability of BBB.Although longterm or high-dose chemotherapy has shown effectiveness in killing GBM cells and preventing recurrence, it also induces toxic effects and drug resistance. 66In certain cases, the development of systemic toxicity, such as myelosuppression, necessitates discontinuation of chemotherapy.Compared to chemotherapy, radiotherapy exhibits lower levels of systemic toxicity and serves as a vital physical treatment modality for eliminating residual microscopic lesions after surgical resection and preventing the recurrence of GBM.Patients undergoing cerebral radiotherapy frequently experience a complication known as radiation-induced brain injury, which contributes to the clinical presentation of increased intracranial pressure. 67Besides, radiation may also induce systemic toxicity, such as lymphopenia, thrombocytopenia, alopecia, fatigue, cognitive impairment, and memory loss. 67ough immunotherapy, including immune checkpoint blockade, oncolytic therapy, and vaccine therapy, has made significant progress in some cancers, the research on immunotherapy for GBMs is still being conducted. 68The targeted agents derived from the antitumoral immune response also induce inflammatory and anti-immune side effects. 69FT offers a non-invasion and portable approach to prolong survival time with fewer side effects.TEFT instruments are accessible to be carried, which means patients can receive tumor-treating fields at their convenience.In contrast to both chemotherapy and radiotherapy could induce resistant GBM cells through enhancing DNA damage response, the existence of GBM stem cells, and remolding the tumor microenvironment, 70 TEFT has few side effects and rare resistance.Our research team found that long-term TEFT does not adversely affect vital organs and tissues, such as kidney, liver, and blood. 59Moreover, clinical trials revealed that the addition of TEFT to TMZ therapy did not exhibit a significant correlation with the occurrence or intensity of systemic adverse events. 14wever, it should be noted that the utilization of TEFT devices may result in a higher occurrence of adverse events specifically related to dermal toxicity beneath the transducer arrays (Table 2).

Skin injury
Consequently, it can be concluded that TEFT represents a viable, secure, and user-friendly therapeutic approach for patients diagnosed with GBM.

| THE PROS PEC TIVELY INNOVATIVE APPLI C ATI ON OF TEF T AND D ISCUSS I ON
The development of TEFT as an innovative therapeutic approach for GBM has prompted the exploration of its full potential through the utilization of advanced iatrotechnique for tumor treatment.To provide a comprehensive overview, we have compiled prospective patents related to TEFT (Table 3) and have also presented a visual representation in the form of a blueprint (Figure 3).
Photodynamic therapy (PDT) involves the utilization of a photosensitizer that is exposed to appropriate illumination light and energy, resulting in the generation of cytotoxic reactive oxygen species (ROS) and subsequent cell death. 71The photosensitizers exhibit a preference for localizing in tumors rather than normal cells, thereby enabling photodynamic therapy to specifically target and eliminate tumor cells.By disturbing the proliferation of dividing cells, the antitumor effect induced by TEFT could be reinforced with combination of photodynamic therapy.Suitable light sources for PDT, such as light-emitting diodes (LEDs), are activated by applying an alternating current field with specific orientation and intensity.By adjusting the field orientation or intensity below the LED turn-on threshold, TEFT can be performed without activating PDT. 72e BBB can be effectively opened by focused ultrasound, excluding vessels with a diameter exceeding 30 μm. 73 In a phase 1 clinical trial involving adults with recurrent GBM, the BBB was successfully opened using a skull-implantable ultrasound device combined with intravenous microbubbles (LIPU-MB). 74The potential of enhancing the reversible opening of the BBB and increasing drug concentration could be further amplified by combining the TA B L E 3 Patents of emerging technologies for TEFT.ultrasound device with TEFT, thereby potentially augmenting the efficacy of chemotherapy drugs.
In conjunction with the integration of scalp electrodes, the universal implantable electrodes generate an electrical field with multiple stereoscopic orientations.This configuration allows for reduced distance to the lesion, independent of the anatomical structure of the scalp and skull, thereby requiring lower voltage and enhancing safety and effectiveness.It is prospective that integrate the implantable electrodes with implantable ultrasound device to form a unified device.
Immunotherapy, encompassing vaccines and adoptive immune cell transfer therapy, represents emerging treatment modalities for GBM patients. 75The implantation of an Ommaya reservoir serves as a approach for immunotherapy, facilitating the delivery of chimeric antigen receptor (CAR) T cells into the cerebrospinal fluid circulation.By integrating the comprehensive design of the Ommaya reservoir and TEFT implantable electrodes with an ultrasound device, a multifaceted therapeutic approach can be achieved, offering enhanced device functionality and mitigating patient distress through a singular surgical intervention.
As TEFT inhibited tumor growth via electric fields, the position of transducer array is vital to optimize the TEFT efficacy.To achieve this, a 3D map of electrical conductivity, resistivity, and power loss density can be generated using magnetic resonance imaging (MRI), 76,77 taking into account the anatomical volume of the target tissue.The utilization of MRI measurements in conjunction with the NovoTAL System (Novocure Ltd.) could adjust the maximal electric field intensity at the tumor site. 78Additionally, a theory of evaluating the quality of segmentation of MRI was developed, and it provided the best segmentation to determine transducer arrays layouts. 79sed on these techniques, adjusting the position of electrodes would elevate the efficacy of TEFT.
Single-cell heterogeneity was inferred because of variable transcription and distinct GBM subtypes in the same tumor. 80tably, the optimal frequencies for GBM varied among different patients and cell types. 8,11The use of a fixed frequency in TEFT only inhibited specific cell types, while exhibiting a weaker inhibitory effect on other heterogeneous cells.Conversely, employing a random frequency in TEFT enhanced the therapeutic effect on GBM, 11 suggesting that the application of a random frequency in TEFT may effectively target heterogeneous cells with varying optimal frequencies.The theory was transferred to a utility device reducing the motility of GBM cells with changing frequency and amplitude every one second. 81Besides, changing the direction of TEFT also enhanced the therapeutic efficacy through promoting cell apoptosis and CD8+ T cell infiltration. 11The selection of the frequency of the alternating electric field can be determined based on the size of the cells through biopsy or inverse electric impedance tomography 82 and electrical characteristics of GBM cells obtained from the patient. 83The implementation of individualized treatment frequencies, the adjustment of switching frequency according to multiple optimal frequencies, and the incorporation of multidirectional mode are expected to significantly enhance the effectiveness of TEFT.Though there were multiple technologies to adjust the position of electrodes to exert the maximal field density on GBM under the same voltage, the prediction of the TEFT treatment efficacy for individual patient was still rarely developed.Digital twins were the virtual counterparts of the entity measures, which witnessed the status of a object much earlier for further optimization. 84,85e application of digital twins could simulate the TEFT and provide the prediction of TEFT efficacy.According to the predictive data, we could adjust the parameters of TEFT equipment, such as the position of electrodes, voltage, and current.As the electrodes of TEFT generating heat during producing electric fields, the sensors monitoring the temperature of electrodes transmitted the data to a central hub and switched off the overheating electrodes. 86,87Digital twin could substitute the role of the central hub to calculate and predict the temperature of electrodes.The efficacy of TEFT was dependent on the compliance of patients 88 and the duration of effective field intensity.As the TEFT equipment was connected to the network and transferred data to digital twin appliance, digital twins could also monitor the use duration of TEFT, especially elevating the duration of effective field intensity.This technology could improve the efficacy of TEFT for supervising all stages of TEFT usage.
In this study, we mainly summarized the innovation and prospective application of TEFT.Previous studies had shown that TEFT inhibited GBM growth in vitro and in vivo, 9,11 and as discussed above, the mechanisms of TEFT were not fully understood.
The researches on mechanisms of TEFT acting on crosstalk between GBM tumor microenvironment would be a hotspot of research field.It is a critical point that develops a TEFT device for cell co-culture and monitoring culture medium component.Neural stem cells (NSCs), mainly existing in the subventricular zone (SVZ), are associated with the origin and recurrence of GBM. 89,90It is worth exploring that the antitumoral effect of TEFT on NSCs located in SVZ.

AUTH O R CO NTR I B UTI O N S
Conceived and designed the review: JLL and LC.Wrote and revised the paper: JXL, YYL, and JYC.All authors contributed to the article and approved the submitted version.
Furthermore, the combination of spindle assembly checkpoint (SAC) inhibitor MPS1-IN-3 (IN-3) and TEFT resulted in a stronger impact on GBM cell lines with an increased apoptotic rate compared to TEFT or IN-3 treatment alone. 58Additionally, the concurrent application of TEFT and anti-PD-1 therapy was found to be safe without causing pathological changes in normal lungs and decreased tumor volume, albeit without statistical significance when compared to monotherapy F I G U R E 2 The current system of TEFT instrument.(A) The head model of TEFT instruments for clinical application (ASCLU-350).(B) The first generation of TEFT instrument for cell culturing.(C) The quadrilateral petri dish for cells in TEFT instruments (CL-301A).(D) The second generation of TEFT instruments for cell culturing (BES-100).(E, F) The TEFT instruments for mouse.TA B L E 1 Summary of clinical trials of TEFT.

F I G U R E 3 | 11 of 14 LAN
The prospect of TEFT plus advanced therapy (By Figdraw).et al. 14
TA B L E 2