1
|
Alshehri AM, Wilson OC. Biomimetic Hydrogel Strategies for Cancer Therapy. Gels 2024; 10:437. [PMID: 39057460 PMCID: PMC11275631 DOI: 10.3390/gels10070437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 06/18/2024] [Accepted: 06/28/2024] [Indexed: 07/28/2024] Open
Abstract
Recent developments in biomimetic hydrogel research have expanded the scope of biomedical technologies that can be used to model, diagnose, and treat a wide range of medical conditions. Cancer presents one of the most intractable challenges in this arena due to the surreptitious mechanisms that it employs to evade detection and treatment. In order to address these challenges, biomimetic design principles can be adapted to beat cancer at its own game. Biomimetic design strategies are inspired by natural biological systems and offer promising opportunities for developing life-changing methods to model, detect, diagnose, treat, and cure various types of static and metastatic cancers. In particular, focusing on the cellular and subcellular phenomena that serve as fundamental drivers for the peculiar behavioral traits of cancer can provide rich insights into eradicating cancer in all of its manifestations. This review highlights promising developments in biomimetic nanocomposite hydrogels that contribute to cancer therapies via enhanced drug delivery strategies and modeling cancer mechanobiology phenomena in relation to metastasis and synergistic sensing systems. Creative efforts to amplify biomimetic design research to advance the development of more effective cancer therapies will be discussed in alignment with international collaborative goals to cure cancer.
Collapse
Affiliation(s)
- Awatef M. Alshehri
- Department of Biomedical Engineering, The Catholic University of America, Washington, DC 20064, USA
- Department of Nanomedicine, King Abdullah International Medical Research Center (KAIMRC), King Saud bin Abdelaziz University for Health Sciences (KSAU-HS), Ministry of National Guard-Health Affairs (MNGHA), Riyadh 11426, Saudi Arabia;
| | - Otto C. Wilson
- Department of Biomedical Engineering, The Catholic University of America, Washington, DC 20064, USA
| |
Collapse
|
2
|
Liao J, Gong L, Xu Q, Wang J, Yang Y, Zhang S, Dong J, Lin K, Liang Z, Sun Y, Mu Y, Chen Z, Lu Y, Zhang Q, Lin Z. Revolutionizing Neurocare: Biomimetic Nanodelivery Via Cell Membranes. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402445. [PMID: 38583077 DOI: 10.1002/adma.202402445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/01/2024] [Indexed: 04/08/2024]
Abstract
Brain disorders represent a significant challenge in medical science due to the formidable blood-brain barrier (BBB), which severely limits the penetration of conventional therapeutics, hindering effective treatment strategies. This review delves into the innovative realm of biomimetic nanodelivery systems, including stem cell-derived nanoghosts, tumor cell membrane-coated nanoparticles, and erythrocyte membrane-based carriers, highlighting their potential to circumvent the BBB's restrictions. By mimicking native cell properties, these nanocarriers emerge as a promising solution for enhancing drug delivery to the brain, offering a strategic advantage in overcoming the barrier's selective permeability. The unique benefits of leveraging cell membranes from various sources is evaluated and advanced technologies for fabricating cell membrane-encapsulated nanoparticles capable of masquerading as endogenous cells are examined. This enables the targeted delivery of a broad spectrum of therapeutic agents, ranging from small molecule drugs to proteins, thereby providing an innovative approach to neurocare. Further, the review contrasts the capabilities and limitations of these biomimetic nanocarriers with traditional delivery methods, underlining their potential to enable targeted, sustained, and minimally invasive treatment modalities. This review is concluded with a perspective on the clinical translation of these biomimetic systems, underscoring their transformative impact on the therapeutic landscape for intractable brain diseases.
Collapse
Affiliation(s)
- Jun Liao
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Lidong Gong
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Qingqiang Xu
- Department of Pharmaceutics, School of Pharmacy, Naval Medical University, Shanghai, 200433, China
| | - Jingya Wang
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Yuanyuan Yang
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Shiming Zhang
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Junwei Dong
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Kerui Lin
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Zichao Liang
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| | - Yuhan Sun
- Department of Pharmaceutics, School of Pharmacy, Naval Medical University, Shanghai, 200433, China
| | - Yongxu Mu
- The First Affiliated Hospital of Baotou Medical College, Inner Mongolia University of Science and Technology, Baotou, 014040, China
| | - Zhengju Chen
- Pooling Medical Research Institutes of 100Biotech, Beijing, 100006, China
| | - Ying Lu
- Department of Pharmaceutics, School of Pharmacy, Naval Medical University, Shanghai, 200433, China
| | - Qiang Zhang
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Zhiqiang Lin
- Institute of Systems Biomedicine, Beijing Key Laboratory of Tumor Systems Biology, School of Basic Medical Sciences, Peking University, Beijing, 100191, China
| |
Collapse
|
3
|
Zhang R, Li X, Zhang S. The Role of Bacteria in Central Nervous System Tumors: Opportunities and Challenges. Microorganisms 2024; 12:1053. [PMID: 38930435 PMCID: PMC11205425 DOI: 10.3390/microorganisms12061053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Revised: 05/19/2024] [Accepted: 05/20/2024] [Indexed: 06/28/2024] Open
Abstract
Tumors of the central nervous system (CNS) are severe and refractory diseases with poor prognosis, especially for patients with malignant glioblastoma and brain metastases. Currently, numerous studies have explored the potential role of bacteria and intestinal flora in tumor development and treatment. Bacteria can penetrate the blood-brain barrier (BBB), targeting the hypoxic microenvironment at the core of tumors, thereby eliminating tumors and activating both the innate and adaptive immune responses, rendering them promising therapeutic agents for CNS tumors. In addition, engineered bacteria and derivatives, such as bacterial membrane proteins and bacterial spores, can also be used as good candidate carriers for targeted drug delivery. Moreover, the intestinal flora can regulate CNS tumor metabolism and influence the immune microenvironment through the "gut-brain axis". Therefore, bacterial anti-tumor therapy, engineered bacterial targeted drug delivery, and intervention of the intestinal flora provide therapeutic modalities for the treatment of CNS tumors. In this paper, we performed a comprehensive review of the mechanisms and therapeutic practices of bacterial therapy for CNS tumors and discussed potential future research directions in this field.
Collapse
Affiliation(s)
| | | | - Si Zhang
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu 610041, China; (R.Z.); (X.L.)
| |
Collapse
|
4
|
Chen X, Li P, Luo B, Song C, Wu M, Yao Y, Wang D, Li X, Hu B, He S, Zhao Y, Wang C, Yang X, Hu J. Surface Mineralization of Engineered Bacterial Outer Membrane Vesicles to Enhance Tumor Photothermal/Immunotherapy. ACS NANO 2024; 18:1357-1370. [PMID: 38164903 DOI: 10.1021/acsnano.3c05714] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
Gram-negative bacteria can naturally produce nanosized spherical outer membrane vesicles (OMVs) with a lipid bilayer membrane, possessing immunostimulatory capabilities to be potentially applied in tumor therapy. However, the systemic toxicity induced by pathogen-associated molecular patterns (PAMPs) of OMVs is the main obstacle for their clinical translation. Herein, melanin-loaded OMVs were produced with a genetic engineering strategy and further coated with calcium phosphate (CaP) to reduce their toxicity to enhance tumor treatment effects. Wild-type bacterium Escherichia coli Nissle 1917 (EcN) was genetically engineered to highly express tyrosinase to catalyze the intracellular synthesis of melanin, giving melanin-loaded OMVs (OMVMel). To reduce the systemic toxicity in tumor therapy, OMVMel was coated with CaP by surface mineralization to obtain OMVMel@CaP. In comparison with OMVMel, OMVMel@CaP showed lower systemic inflammatory responses in healthy mice and less damage to the liver, spleen, lung, and kidney, so the administration dose could be increased to enhance the antitumor effect. In the acidic tumor microenvironment, the CaP shell disintegrated to release OMVMel to trigger antitumor immune responses. Under costimulation of OMVMel acting as immunoadjuvants and the damage-associated molecular patterns (DAMPs) released by the photothermal effect, the efficiency of tumor photothermal/immunotherapy was largely boosted through promoting the infiltration of matured DCs, M1 macrophages, and activated CD8+ T cells, decreasing the ratio of MDSCs in tumors.
Collapse
Affiliation(s)
| | | | - Ban Luo
- Department of Ophthalmology, Wenchang People's Hospital, Wenchang 571321, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | | - Jun Hu
- Hubei Jiangxia Laboratory, Wuhan 430200, People's Republic of China
| |
Collapse
|
5
|
Ji N, Wang F, Wang M, Zhang W, Liu H, Su J. Engineered bacterial extracellular vesicles for central nervous system diseases. J Control Release 2023; 364:46-60. [PMID: 37866404 DOI: 10.1016/j.jconrel.2023.10.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/17/2023] [Accepted: 10/18/2023] [Indexed: 10/24/2023]
Abstract
The prevalence of central nervous system (CNS) diseases is on the rise as the population ages. The presence of various obstacles, particularly the blood-brain barrier (BBB), poses a challenge for drug delivery to the CNS. An expanding body of study suggests that gut microbiota (GM) plays an important role in CNS diseases. The communication between GM and CNS diseases has received increasing attention. Accumulating evidence indicates that the GM can modulate host signaling pathways to regulate distant organ functions by delivering bioactive substances to host cells via bacterial extracellular vesicles (BEVs). BEVs have emerged as a promising platform for the treatment of CNS diseases due to their nanostructure, ability to penetrate the BBB, as well as their low toxicity, high biocompatibility, ease of modification and large-scale culture. Here, we discuss the biogenesis, internalization mechanism and engineering modification methods of BEVs. We then focus on the use and potential role of BEVs in the treatment of CNS diseases. Finally, we outline the main challenges and future prospects for the application of BEVs in CNS diseases. We hope that the comprehensive understanding of the BEVs-based gut-brain axis will provide new insights into the treatment of CNS diseases.
Collapse
Affiliation(s)
- Ning Ji
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; National Center for Translational Medicine (Shanghai) SHU Branch, Shanghai University, Shanghai 200444, China
| | - Fuxiao Wang
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; National Center for Translational Medicine (Shanghai) SHU Branch, Shanghai University, Shanghai 200444, China
| | - Miaomiao Wang
- Department of Rehabilitation Medicine, Shanghai Zhongye Hospital, Shanghai 200941, China
| | - Wencai Zhang
- Department of Orthopedics, The First Affiliated Hospital of Jinan University, Guangdong, Guangzhou 510630, China.
| | - Han Liu
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; National Center for Translational Medicine (Shanghai) SHU Branch, Shanghai University, Shanghai 200444, China.
| | - Jiacan Su
- Institute of Translational Medicine, Shanghai University, Shanghai 200444, China; Organoid Research Center, Shanghai University, Shanghai 200444, China; National Center for Translational Medicine (Shanghai) SHU Branch, Shanghai University, Shanghai 200444, China; Department of Orthopedics, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200092, China.
| |
Collapse
|
6
|
Song X, Qian H, Yu Y. Nanoparticles Mediated the Diagnosis and Therapy of Glioblastoma: Bypass or Cross the Blood-Brain Barrier. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2302613. [PMID: 37415556 DOI: 10.1002/smll.202302613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 06/19/2023] [Indexed: 07/08/2023]
Abstract
Glioblastoma is one of the most aggressive central nervous system malignancies with high morbidity and mortality. Current clinical approaches, including surgical resection, radiotherapy, and chemotherapy, are limited by the difficulty of targeting brain lesions accurately, leading to disease recurrence and fatal outcomes. The lack of effective treatments has prompted researchers to continuously explore novel therapeutic strategies. In recent years, nanomedicine has made remarkable progress and expanded its application in brain drug delivery, providing a new treatment for brain tumors. Against this background, this article reviews the application and progress of nanomedicine delivery systems in brain tumors. In this paper, the mechanism of nanomaterials crossing the blood-brain barrier is summarized. Furthermore, the specific application of nanotechnology in glioblastoma is discussed in depth.
Collapse
Affiliation(s)
- Xiaowei Song
- Department of Radiology, Anhui Provincial Institute of Translational Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, No. 218, Jixi Road, Shushan District, Hefei, 230022, P. R. China
- Research Center of Clinical Medical Imaging, Hefei, 230022, China
| | - Haisheng Qian
- School of Biomedical Engineering, Anhui Provincial Institute of Translational Medicine, Anhui Medical University, Hefei, 230011, P. R. China
- Anhui Engineering Research Center for Medical Micro-Nano Devices, Hefei, 230011, China
| | - Yongqiang Yu
- Department of Radiology, Anhui Provincial Institute of Translational Medicine, The First Affiliated Hospital of Anhui Medical University, Anhui Medical University, No. 218, Jixi Road, Shushan District, Hefei, 230022, P. R. China
- Research Center of Clinical Medical Imaging, Hefei, 230022, China
| |
Collapse
|
7
|
Yu H, Zhang S, Yang H, Miao J, Ma X, Xiong W, Chen G, Ji T. Specific interaction based drug loading strategies. NANOSCALE HORIZONS 2023; 8:1523-1528. [PMID: 37592921 DOI: 10.1039/d3nh00165b] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/19/2023]
Abstract
Drug carriers have been commonly used for drug control release, enhancing drug efficacy and/or minimizing side-effects. However, it is still difficult to get a high loading efficiency when encapsulating super hydrophilic drugs with a narrow therapeutic index, such as many neurotoxins. Increasing the carrier proportion can improve drug loading to a certain degree, while the burst released drug when the formulation enters the body may cause overdose side-effects. Moreover, high-dose carriers themselves may increase the metabolic burden of the body. Hence, new drug carriers and/or loading strategies are urgently needed to promote the applications of these drugs. This minireview will introduce drug loading strategies based on specific interactions (between drugs and carriers) and will discuss the challenges and perspectives of these strategies. This work is expected to provide alternative inspiration for the delivery of hydrophilic drugs.
Collapse
Affiliation(s)
- Haoqi Yu
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center of Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- Sino-Danish College, Sino-Danish Center for Education and Research, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shuhui Zhang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center of Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
| | - Huiru Yang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center of Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
| | - Jiamin Miao
- Department of Anesthesiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310012, China.
| | - Xu Ma
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center of Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
| | - Wei Xiong
- Department of Anesthesiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310012, China.
| | - Gang Chen
- Department of Anesthesiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310012, China.
| | - Tianjiao Ji
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center of Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- Department of Anesthesiology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang Province 310012, China.
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| |
Collapse
|
8
|
Zong R, Ruan H, Liu C, Fan S, Li J. Bacteria and Bacterial Components as Natural Bio-Nanocarriers for Drug and Gene Delivery Systems in Cancer Therapy. Pharmaceutics 2023; 15:2490. [PMID: 37896250 PMCID: PMC10610331 DOI: 10.3390/pharmaceutics15102490] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 10/06/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
Bacteria and bacterial components possess multifunctional properties, making them attractive natural bio-nanocarriers for cancer diagnosis and targeted treatment. The inherent tropic and motile nature of bacteria allows them to grow and colonize in hypoxic tumor microenvironments more readily than conventional therapeutic agents and other nanomedicines. However, concerns over biosafety, limited antitumor efficiency, and unclear tumor-targeting mechanisms have restricted the clinical translation and application of natural bio-nanocarriers based on bacteria and bacterial components. Fortunately, bacterial therapies combined with engineering strategies and nanotechnology may be able to reverse a number of challenges for bacterial/bacterial component-based cancer biotherapies. Meanwhile, the combined strategies tend to enhance the versatility of bionanoplasmic nanoplatforms to improve biosafety and inhibit tumorigenesis and metastasis. This review summarizes the advantages and challenges of bacteria and bacterial components in cancer therapy, outlines combinatorial strategies for nanocarriers and bacterial/bacterial components, and discusses their clinical applications.
Collapse
Affiliation(s)
| | | | | | - Shaohua Fan
- School of Life Science, Jiangsu Normal University, Xuzhou 221116, China
| | - Jun Li
- School of Life Science, Jiangsu Normal University, Xuzhou 221116, China
| |
Collapse
|
9
|
Kannan S, Cheng VWT. Nanoparticle drug delivery to target breast cancer brain metastasis: Current and future trends. Int J Cancer 2023; 153:1118-1129. [PMID: 37096795 DOI: 10.1002/ijc.34542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 04/26/2023]
Abstract
Breast cancer brain metastasis (BCBM) is rapidly becoming an impediment to continuing survival gains seen in breast cancer patients. Drug delivery across the blood-brain barrier is the main issue hindering systemic therapy against BCBM. This review details recent advances in nanoparticle (NP) drug delivery systems to target BCBM. Their primary benefits are: enhanced circulating and intra-BCBM drug biodistribution, BCBM targeting through NP functionalization, opportunities for gene manipulation and their theragnostic applications. Multiple NPs have been synthesized to deliver therapeutic HER2 blockade, which is particularly important given HER2-positive breast cancer's tendency to form BCBM. Finally, we review the clinical context in which NP-based therapeutics have been investigated in BCBM patients. While a breakthrough in improving patient outcomes remain awaited, these clinical trials represent positive steps in the changing attitude towards BCBM as a treatable illness. Although multiple challenges remain in the clinical translation of BCBM-directed NP therapies, ongoing research in the field offers promising avenues for novel targeting of this devastating disease.
Collapse
Affiliation(s)
- Siddarth Kannan
- School of Medicine, University of Central Lancashire, Preston, UK
| | - Vinton W T Cheng
- Leeds Institute of Medical Research, University of Leeds, Leeds, UK
| |
Collapse
|
10
|
Li J, Wang H. Selective organ targeting nanoparticles: from design to clinical translation. NANOSCALE HORIZONS 2023; 8:1155-1173. [PMID: 37427677 DOI: 10.1039/d3nh00145h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Targeting nanoparticle is a very promising therapeutic approach that can precisely target specific sites to treat diseases. Research on nanoscale drug delivery systems has made great progress in the past few years, making targeting nanoparticles a promising prospect. However, selective targeting nanoparticles designed for specific organs still face several challenges, one of which is the unknown fate of nanoparticles in vivo. This review starts with the in vivo journey of nanoparticles and describes the biological barriers and some targeting strategies for nanoparticles to target specific organs. Then, through the collection of literature in recent years, the design of selective targeting nanoparticles for various organs is illustrated, which provides a reference strategy for people to study the design of selective organ targeting nanoparticles. Ultimately, the prospect and challenge of selective organ targeting nanoparticles are discussed by collecting the data of clinical trials and marketed drugs.
Collapse
Affiliation(s)
- Jian Li
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hai Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China
| |
Collapse
|
11
|
Zhou M, Chen H, Zeng Y, Lv Z, Hu X, Tong Y, Wang P, Zhao M, Mu R, Yu J, Chen Y, Wei L, Gu J, Lan Q, Zhen X, Han L. DH5α Outer Membrane-Coated Biomimetic Nanocapsules Deliver Drugs to Brain Metastases but not Normal Brain Cells via Targeting GRP94. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300403. [PMID: 37104822 DOI: 10.1002/smll.202300403] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 04/17/2023] [Indexed: 06/19/2023]
Abstract
Receptor-mediated vesicular transport has been extensively developed to penetrate the blood-brain barrier (BBB) and has emerged as a class of powerful brain-targeting delivery technologies. However, commonly used BBB receptors such as transferrin receptor and low-density lipoprotein receptor-related protein 1, are also expressed in normal brain parenchymal cells and can cause drug distribution in normal brain tissues and subsequent neuroinflammation and cognitive impairment. Here, the endoplasmic reticulum residing protein GRP94 is found upregulated and relocated to the cell membrane of both BBB endothelial cells and brain metastatic breast cancer cells (BMBCCs) by preclinical and clinical investigations. Inspired by that Escherichia coli penetrates the BBB via the binding of its outer membrane proteins with GRP94, avirulent DH5α outer membrane protein-coated nanocapsules (Omp@NCs) are developed to cross the BBB, avert normal brain cells, and target BMBCCs via recognizing GRP94. Embelin (EMB)-loaded Omp@EMB specifically reduce neuroserpin in BMBCCs, which inhibits vascular cooption growth and induces apoptosis of BMBCCs by restoring plasmin. Omp@EMB plus anti-angiogenic therapy prolongs the survival of mice with brain metastases. This platform holds the translational potential to maximize therapeutic effects on GRP94-positive brain diseases.
Collapse
Affiliation(s)
- Mengyuan Zhou
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
- MJiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Haiyan Chen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Yuteng Zeng
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Ziyan Lv
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Xiaoxiao Hu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Yang Tong
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Pan Wang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Mei Zhao
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Rui Mu
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Ju Yu
- Department of Neurosurgery, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215004, P. R. China
| | - Yanming Chen
- Department of Neurosurgery, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215004, P. R. China
| | - Lin Wei
- MJiangsu Key Laboratory of Infection and Immunity, Institutes of Biology and Medical Sciences, Soochow University, Suzhou, 215123, P. R. China
- School of Life Science, Anhui Medical University, Hefei, 230032, P. R. China
| | - Jiang Gu
- National Engineering Research Centre of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Chongqing, 400038, P. R. China
| | - Qing Lan
- Department of Neurosurgery, The Second Affiliated Hospital of Soochow University, Soochow University, Suzhou, 215004, P. R. China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| | - Liang Han
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou, 215123, P. R. China
| |
Collapse
|
12
|
Wei Y, Xia X, Li H, Gao H. Influence factors on and potential strategies to amplify receptor-mediated nanodrug delivery across the blood-brain barrier. Expert Opin Drug Deliv 2023; 20:1713-1730. [PMID: 37542516 DOI: 10.1080/17425247.2023.2245332] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/22/2023] [Accepted: 08/03/2023] [Indexed: 08/07/2023]
Abstract
INTRODUCTION A major challenge in treating central nervous system (CNS) disorders is to achieve adequate drug delivery across the blood-brain barrier (BBB). Receptor-mediated nanodrug delivery as a Trojan horse strategy has become an exciting approach. However, these nanodrugs do not accumulate significantly in the brain parenchyma, which greatly limits the therapeutic effect of drugs. Amplifying the efficiency of receptor-mediated nanodrug delivery across the BBB becomes the holy grail in the treatment of CNS disorders. AREAS COVERED In this review, we tend to establish links between dynamic BBB and receptor-mediated nanodrug delivery, starting with the delivery processes across the BBB, describing factors affecting nanodrug delivery efficiency, and summarizing potential strategies that may amplify delivery efficiency. EXPERT OPINION Receptor-mediated nanodrug delivery is a common approach to significantly enhance the efficiency of brain-targeting delivery. As BBB is constantly undergoing changes, it is essential to investigate the impact of diseases on the effectiveness of brain-targeting nanodrug delivery. More critically, there are several barriers to achieving brain-targeting nanodrug delivery in the five stages of receptor-mediated transcytosis (RMT), and the impacts can be conflicting, requiring intricate balance. Further studies are also needed to investigate the material toxicity of nanodrugs to address the issue of clinical translation.
Collapse
Affiliation(s)
- Ya Wei
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
| | - Xue Xia
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
| | - Hanmei Li
- School of Food and Biological Engineering, Chengdu University, Chengdu, P. R. China
| | - Huile Gao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
| |
Collapse
|
13
|
Li J, Zeng H, Li L, Song M, Dong M. Biomembrane-wrapped gene delivery nanoparticles for cancer therapy. Front Bioeng Biotechnol 2023; 11:1211753. [PMID: 37351470 PMCID: PMC10282192 DOI: 10.3389/fbioe.2023.1211753] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 05/29/2023] [Indexed: 06/24/2023] Open
Abstract
As a promising strategy, gene delivery for cancer treatment accepts encouraging progress due to its high efficacy, low toxicity, and exclusive selectivity. However, the delivery efficiency, specific biological distribution, targeted uptake, and biosafety of naked nucleic acid agents still face serious challenges, which limit further clinical application. To overcome the above bottleneck, safe and efficient functional nanovectors are developed to improve the delivery efficiency of nucleic acid agents. In recent years, emerging membrane-wrapped biomimetic nanoparticles (MBNPs) based on the concept of "imitating nature" are well known for their advantages, such as low immunogenicity and long cycle time, and especially play a crucial role in improving the overall efficiency of gene delivery and reducing adverse reactions. Therefore, combining MBNPs and gene delivery is an effective strategy to enhance tumor treatment efficiency. This review presents the mechanism of gene therapy and the current obstacles to gene delivery. Remarkably, the latest development of gene delivery MBNPs and the strategies to overcome these obstacles are summarized. Finally, the future challenges and prospects of gene delivery MBNPs toward clinical transformation are introduced. The principal purpose of this review is to discuss the biomedical potential of gene delivery MBNPs for cancer therapy and to provide guidance for further enhancing the efficiency of tumor gene therapy.
Collapse
Affiliation(s)
- Jie Li
- Department of Geriatrics, Chengdu Fifth People’s Hospital, Geriatric Diseases Institute of Chengdu, Chengdu, Sichuan, China
- Center for Medicine Research and Translation, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
| | - Huamin Zeng
- Chengdu Ping An Healthcare Medical Examination Laboratory, Chengdu, Sichuan, China
| | - Luwei Li
- College of Clinical Medical, Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan, China
| | - Ming Song
- Department of Pathophysiology, Shenzhen University Health Science Center, Shenzhen, Guangdong, China
| | - Mingqing Dong
- Department of Geriatrics, Chengdu Fifth People’s Hospital, Geriatric Diseases Institute of Chengdu, Chengdu, Sichuan, China
- Center for Medicine Research and Translation, Chengdu Fifth People’s Hospital, Chengdu, Sichuan, China
| |
Collapse
|
14
|
Doré E, Boilard E. Bacterial extracellular vesicles and their interplay with the immune system. Pharmacol Ther 2023; 247:108443. [PMID: 37210006 DOI: 10.1016/j.pharmthera.2023.108443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/09/2023] [Accepted: 05/15/2023] [Indexed: 05/22/2023]
Abstract
The mammalian intestinal tract harbors trillions of microorganisms confined within this space by mucosal barriers. Despite these barriers, bacterial components may still be found elsewhere in the body, even in healthy subjects. Bacteria can release small lipid-bound particles, also named bacterial extracellular vesicles (bEV). While bacteria themselves cannot normally penetrate the mucosal defense, bEVs may infiltrate the barrier and disseminate throughout the body. The extremely diverse cargo that bEVs can carry, depending on their parent species, strain, and growth conditions, grant them an equally broad potential to interact with host cells and influence immune functions. Herein, we review the current knowledge of processes underlying the uptake of bEVs by mammalian cells, and their effect on the immune system. Furthermore, we discuss how bEVs could be targeted and manipulated for diverse therapeutic purposes.
Collapse
Affiliation(s)
- Etienne Doré
- Centre de Recherche du Centre Hospitalier Universitaire de Québec - Université Laval, Québec, QC, Canada; Centre de Recherche ARThrite - Arthrite, Recherche, Traitements, Université Laval, Québec, QC, Canada
| | - Eric Boilard
- Centre de Recherche du Centre Hospitalier Universitaire de Québec - Université Laval, Québec, QC, Canada; Centre de Recherche ARThrite - Arthrite, Recherche, Traitements, Université Laval, Québec, QC, Canada.
| |
Collapse
|
15
|
Lu J, Ding J, Chu B, Ji C, Zhang Q, Xu Y, Song B, Wang H, He Y. Inactive Trojan Bacteria as Safe Drug Delivery Vehicles Crossing the Blood-Brain Barrier. NANO LETTERS 2023; 23:4326-4333. [PMID: 37130058 DOI: 10.1021/acs.nanolett.3c00563] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Escherichia coli K1 (EC-K1) can bypass the blood-brain barrier (BBB) and cause meningitis. Excitingly, we find the "dead EC-K1" can safely penetrate the BBB because they retain the intact structure and chemotaxis of the live EC-K1, while losing their pathogenicity. Based on this, we develop a safe "dead EC-K1"-based drug delivery system, in which EC-K1 engulf the maltodextrin (MD)-modified therapeutics through the bacteria-specific MD transporter pathway, followed by the inactivation via UV irradiation. We demonstrate that the dead bacteria could carry therapeutics (e.g., indocyanine green (ICG)) and together bypass the BBB after intravenous injection into the mice, delivering ∼3.0-fold higher doses into the brain than free ICG under the same conditions. What is more, all mice remain healthy even after 14 days of intravenous injection of ∼109 CFU of inactive bacteria. As a proof of concept, we demonstrate the developed strategy enables the therapy of bacterial meningitis and glioblastoma in mice.
Collapse
Affiliation(s)
- Jianping Lu
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Jiali Ding
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Binbin Chu
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Chen Ji
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Qian Zhang
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Yanan Xu
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Bin Song
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Houyu Wang
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| | - Yao He
- Suzhou Key Laboratory of Nanotechnology and Biomedicine, Institute of Functional Nano and Soft Materials (FUNSOM) and Collaborative Innovation Center of Suzhou Nano Science and Technology (NANO-CIC), Soochow University, Suzhou 215123, China
| |
Collapse
|
16
|
Ou A, Wang Y, Zhang J, Huang Y. Living Cells and Cell-Derived Vesicles: A Trojan Horse Technique for Brain Delivery. Pharmaceutics 2023; 15:pharmaceutics15041257. [PMID: 37111742 PMCID: PMC10145830 DOI: 10.3390/pharmaceutics15041257] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/30/2023] [Accepted: 04/06/2023] [Indexed: 04/29/2023] Open
Abstract
Brain diseases remain a significant global healthcare burden. Conventional pharmacological therapy for brain diseases encounters huge challenges because of the blood-brain barrier (BBB) limiting the delivery of therapeutics into the brain parenchyma. To address this issue, researchers have explored various types of drug delivery systems. Cells and cell derivatives have attracted increasing interest as "Trojan horse" delivery systems for brain diseases, owing to their superior biocompatibility, low immunogenicity, and BBB penetration properties. This review provided an overview of recent advancements in cell- and cell-derivative-based delivery systems for the diagnosis and treatment of brain diseases. Additionally, it discussed the challenges and potential solutions for clinical translation.
Collapse
Affiliation(s)
- Ante Ou
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuewei Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiaxin Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Yongzhuo Huang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zhongshan 528437, China
- NMPA Key Laboratory for Quality Research and Evaluation of Pharmaceutical Excipients, Shanghai 201203, China
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| |
Collapse
|
17
|
Sharma S, Dang S. Nanocarrier-Based Drug Delivery to Brain: Interventions of Surface Modification. Curr Neuropharmacol 2023; 21:517-535. [PMID: 35794771 PMCID: PMC10207924 DOI: 10.2174/1570159x20666220706121412] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 04/29/2022] [Accepted: 05/14/2022] [Indexed: 11/22/2022] Open
Abstract
Brain disorders are a prevalent and rapidly growing problem in the medical field as they adversely affect the quality of life of a human. With an increase in life expectancy, it has been reported that diseases like Alzheimer's, Parkinson's, stroke and brain tumors, along with neuropsychological disorders, are also being reported at an alarmingly high rate. Despite various therapeutic methods for treating brain disorders, drug delivery to the brain has been challenging because of a very complex Blood Brain Barrier, which precludes most drugs from entering the brain in effective concentrations. Nano-carrier-based drug delivery systems have been reported widely by researchers to overcome this barrier layer. These systems due to their small size, offer numerous advantages; however, their short residence time in the body owing to opsonization hinders their success in vivo. This review article focuses on the various aspects of modifying the surfaces of these nano-carriers with polymers, surfactants, protein, antibodies, cell-penetrating peptides, integrin binding peptides and glycoproteins such as transferrin & lactoferrin leading to enhanced residence time, desirable characteristics such as the ability to cross the blood-brain barrier (BBB), increased bioavailability in regions of the brain and targeted drug delivery.
Collapse
Affiliation(s)
- Surbhi Sharma
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, UP, India
| | - Shweta Dang
- Department of Biotechnology, Jaypee Institute of Information Technology, Noida, UP, India
| |
Collapse
|
18
|
Brain Delivery of IGF1R5, a Single-Domain Antibody Targeting Insulin-like Growth Factor-1 Receptor. Pharmaceutics 2022; 14:pharmaceutics14071452. [PMID: 35890347 PMCID: PMC9316817 DOI: 10.3390/pharmaceutics14071452] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 07/05/2022] [Accepted: 07/08/2022] [Indexed: 02/04/2023] Open
Abstract
The ability of drugs and therapeutic antibodies to reach central nervous system (CNS) targets is greatly diminished by the blood–brain barrier (BBB). Receptor-mediated transcytosis (RMT), which is responsible for the transport of natural protein ligands across the BBB, was identified as a way to increase drug delivery to the brain. In this study, we characterized IGF1R5, which is a single-domain antibody (sdAb) that binds to insulin-like growth factor-1 receptor (IGF1R) at the BBB, as a ligand that triggers RMT and could deliver cargo molecules that otherwise do not cross the BBB. Surface plasmon resonance binding analyses demonstrated the species cross-reactivity of IGF1R5 toward IGF1R from multiple species. To overcome the short serum half-life of sdAbs, we fused IGF1R5 to the human (hFc) or mouse Fc domain (mFc). IGF1R5 in both N- and C-terminal mFc fusion showed enhanced transmigration across a rat BBB model (SV-ARBEC) in vitro. Increased levels of hFc-IGF1R5 in the cerebrospinal fluid and vessel-depleted brain parenchyma fractions further confirmed the ability of IGF1R5 to cross the BBB in vivo. We next tested whether this carrier was able to ferry a pharmacologically active payload across the BBB by measuring the hypothermic and analgesic properties of neurotensin and galanin, respectively. The fusion of IGF1R5-hFc to neurotensin induced a dose-dependent reduction in the core temperature. The reversal of hyperalgesia by galanin that was chemically linked to IGF1R5-mFc was demonstrated using the Hargreaves model of inflammatory pain. Taken together, our results provided a proof of concept that appropriate antibodies, such as IGF1R5 against IGF1R, are suitable as RMT carriers for the delivery of therapeutic cargos for CNS applications.
Collapse
|
19
|
Haiyan C, Mengyuan Z, Yuteng Z, Ziyan L, Pan W, Han L. Recent advances on biomedical applications of bacterial outer membrane vesicles. J Mater Chem B 2022; 10:7384-7396. [DOI: 10.1039/d2tb00683a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanoscale and non-self-replicating outer membrane vesicles (OMVs) are naturally secreted by some bacteria with their structures and compositions similar to that of the outer membrane of parental bacteria. With some...
Collapse
|