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Frutos-Grilo E, Ana Y, Gonzalez-de Miguel J, Cardona-I-Collado M, Rodriguez-Arce I, Serrano L. Bacterial live therapeutics for human diseases. Mol Syst Biol 2024; 20:1261-1281. [PMID: 39443745 PMCID: PMC11612307 DOI: 10.1038/s44320-024-00067-0] [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: 06/13/2024] [Revised: 08/19/2024] [Accepted: 09/12/2024] [Indexed: 10/25/2024] Open
Abstract
The genomic revolution has fueled rapid progress in synthetic and systems biology, opening up new possibilities for using live biotherapeutic products (LBP) to treat, attenuate or prevent human diseases. Among LBP, bacteria-based therapies are particularly promising due to their ability to colonize diverse human tissues, modulate the immune system and secrete or deliver complex biological products. These bacterial LBP include engineered pathogenic species designed to target specific diseases, and microbiota species that promote microbial balance and immune system homeostasis, either through local administration or the gut-body axes. This review focuses on recent advancements in preclinical and clinical trials of bacteria-based LBP, highlighting both on-site and long-reaching strategies.
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Affiliation(s)
- Elisabet Frutos-Grilo
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Yamile Ana
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Javier Gonzalez-de Miguel
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Marcel Cardona-I-Collado
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Irene Rodriguez-Arce
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.
| | - Luis Serrano
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.
- ICREA, Pg. Lluis Companys 23, Barcelona, Spain.
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Lorefice L, Zoledziewska M. Propionic Acid Impact on Multiple Sclerosis: Evidence and Challenges. Nutrients 2024; 16:3887. [PMID: 39599673 PMCID: PMC11597849 DOI: 10.3390/nu16223887] [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: 10/23/2024] [Revised: 11/05/2024] [Accepted: 11/13/2024] [Indexed: 11/29/2024] Open
Abstract
Accumulating evidence suggests that multiple sclerosis (MS) is an environmentally influenced disorder with contributions from life-time exposure to factors including Epstein-Barr virus infection or shifts in microbiome, diet and lifestyle. One suggested factor is a deficiency in propionic acid, a short-chain fatty acid produced by gut bacteria that may contribute to the disease pathology both in animal models and in human cases of MS. Propionate appears to exert beneficial effects on the immune, peripheral and central nervous systems of people with MS (pwMS), showing immunoregulatory, neuroprotective and neurogenerative effects. These functions are crucial, given that MS is characterized by immune-mediated damage of myelin in the central nervous system. Accordingly, propionate supplementation or a modulated increase in its levels through the microbiome and diet may help counteract the pro-inflammatory state in MS by directly regulating immune system and/or by decreasing permeability of gut barrier and blood-brain barrier. This could potentially improve outcomes when used with immune-modulating therapy. However, while its broad effects are promising, further large clinical trials are necessary to evaluate its efficacy and safety in pwMS and clarify its role as a complementary therapeutic strategy. This review provides a comprehensive analysis of the evidence, challenges and limitations concerning propionic acid supplementation in MS.
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Affiliation(s)
- Lorena Lorefice
- Multiple Sclerosis Center, ASL Cagliari, Department of Medical Sciences and Public Health, Binaghi Hospital, University of Cagliari, via Is Guadazzonis 2, 09126 Cagliari, Italy;
| | - Magdalena Zoledziewska
- Institute of Genetic and Biomedical Research (IRGB), Italian National Research Council (CNR), 09042 Monserrato, Italy
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Khalifa A, Alkuwayti MA, Abdallah BM, Ali EM, Ibrahim HIM. Probiotic and Rice-Derived Compound Combination Mitigates Colitis Severity. Pharmaceuticals (Basel) 2024; 17:1463. [PMID: 39598375 PMCID: PMC11597685 DOI: 10.3390/ph17111463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2024] [Revised: 10/07/2024] [Accepted: 10/30/2024] [Indexed: 11/29/2024] Open
Abstract
BACKGROUND This study investigated the ability of Enterococcus lactis (E. lactis) and Hasawi rice protein lysate (HPL) to suppress colitis induced by dextran sulfate sodium (DSS) in miceColitis is characterized by inflammation of the colon, and exploring potential therapeutic agents could lead to improved management strategies. METHODS Male mice were subjected to DSS treatment to induce colitis, followed by supplementation with E. lactis and/or HPL. The study assessed various parameters, including disease activity index (DAI) scores, gut permeability measured using FITC-dextran, and superoxide dismutase (SOD) activity in excised colon tissues from both treated and untreated control groups. RESULTS E. lactis supplementation significantly alleviated DSS-induced colitis, as evidenced by improved DAI scores and enhanced gut permeability. Notably, E. lactis combined with HPL (0.1 mg/108) exhibited superior tolerance to a 0.5% pancreatin solution compared to E. lactis alone. Both E. lactis and the combination treatment significantly increased SOD activity (5.6 ± 0.23 SOD U/mg protein for E. lactis and 6.7 ± 0.23 SOD U/mg protein for the combination) relative to the Azoxymethane (AOM)/DSS group, suggesting a reduction in oxidative stress. Additionally, pro-inflammatory markers were significantly reduced in the group receiving both E. lactis and HPL compared to the E. lactis-only group. Levels of proteins associated with cell death, such as PCNA, PTEN, VEGF, COX-2, and STAT-3, were significantly decreased by 14.8% to 80% following E. lactis supplementation, with the combination treatment showing the most pronounced effects. CONCLUSIONS These findings suggest E. lactis supplementation may be beneficial for colitis, with HPL potential to enhance its effectiveness.
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Affiliation(s)
- Ashraf Khalifa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Mayyadah Abdullah Alkuwayti
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Basem M. Abdallah
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Enas M. Ali
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Hairul Islam M. Ibrahim
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Molecular Biology Division, Pondicherry Centre for Biological Sciences and Educational Trust, Pondicherry 605004, India
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Morin CR, Baeva ME, Hollenberg MD, Brain MC. Milk and multiple sclerosis: A possible link? Mult Scler Relat Disord 2024; 83:105477. [PMID: 38308914 DOI: 10.1016/j.msard.2024.105477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/07/2024] [Accepted: 01/26/2024] [Indexed: 02/05/2024]
Abstract
Despite having been formally defined over 150 years ago, the etiology of multiple sclerosis (MS) is still relatively unknown. However, it is now recognized as a multifactorial disease in which genetics, infection, immune function, and environment play a role. We propose an additional piece to the puzzle: milk. In this review, milk is highlighted as a potential risk factor for MS. We examine the overall correlation between bovine milk consumption and the incidence of MS. We then discuss possible mechanisms that may explain the positive association between milk consumption and the development of MS. For instance, butyrophilin (BTN), a milk glycoprotein, can provide molecular mimicry of myelin oligodendrocyte glycoprotein and induce an autoinflammatory response against myelin. Other milk components such as casein, gangliosides, xanthine oxidase, and saturated fats are also analyzed for their potential involvement in the pathophysiology of MS. Finally, we fit milk alongside other well known risk factors of MS: vitamin D levels, Epstein Barr virus infection, and gut dysbiosis. In conclusion, this review summarizes potential mechanisms linking milk as an underappreciated potential risk factor for the development of MS.
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Affiliation(s)
- Caleb R Morin
- University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
| | | | - Morley D Hollenberg
- Department of Physiology & Pharmacology, University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
| | - Michael C Brain
- Department of Biochemistry and Molecular Biology, University of Calgary Cumming School of Medicine, Calgary, AB T2N 4N1, Canada
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Hasaniani N, Ghasemi-Kasman M, Halaji M, Rostami-Mansoor S. Bifidobacterium breve Probiotic Compared to Lactobacillus casei Causes a Better Reduction in Demyelination and Oxidative Stress in Cuprizone-Induced Demyelination Model of Rat. Mol Neurobiol 2024; 61:498-509. [PMID: 37639065 DOI: 10.1007/s12035-023-03593-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 08/17/2023] [Indexed: 08/29/2023]
Abstract
Despite the anatomical separation, strong evidence suggested a bidirectional association between gut microbiota and central nervous system. Cross-talk between gut microbiota and brain has an important role in the pathophysiology of neurodegenerative disorders and regenerative processes. However, choosing the appropriate probiotics and combination therapy of probiotics to provide a synergistic effect is very crucial. In the present study, we investigated the effect of Lactobacillus casei (L. casei) and Bifidobacterium breve (B. breve) on alternation performance, oxidant/antioxidant biomarkers, the extent of demyelination, and the expression level of HO-1, Nrf-2, Olig2, MBP, PDGFRα, and BDNF in cuprizone (CPZ)-induced demyelination model of rat corpus callosum. In order to induce this model, rats received oral administration of CPZ 0.6% w/w in corn oil for 28 days. Then, L. casei, B. breve, or their combinations were orally administrated for 28 days. Y maze test was performed to investigate the alternation performance. Oxidant/antioxidant biomarkers were determined by colorimetric methods. Extent of demyelination was investigated using FluoroMyelin staining. The genes' expression levels of antioxidant and myelin lineage cells were assessed by quantitative real time PCR. The results showed the probiotics supplementation significantly improve the alternation performance and antioxidant capacity in demyelinated corpus callosum. Interestingly, B. breve supplementation alleviated demyelination and oxidative stress levels more than the administration of L. casei alone or the combination of two probiotics. These observations suggest that B. breve could provide a supplementary strategy for the treatment of multiple sclerosis by increasing antioxidant capacity and remyelination.
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Affiliation(s)
- Nima Hasaniani
- Student Research Committee, Babol University of Medical Sciences, Babol, Iran
- Department of Clinical Biochemistry, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Maryam Ghasemi-Kasman
- Cellular and Molecular Biology Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran
- Department of Physiology, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Mehrdad Halaji
- Infectious Diseases and Tropical Medicine Research Center, Babol University of Medical Sciences, Babol, Iran
| | - Sahar Rostami-Mansoor
- Department of Clinical Biochemistry, Faculty of Medicine, Babol University of Medical Sciences, Babol, Iran.
- Department of Laboratory Sciences, Faculty of Paramedical Sciences, Babol University of Medical Sciences, Babol, Iran.
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Alsaud N, Almajed A, Lwusaybie A, Alsubaie A, Alobaidan H, Alessa J, Almousa A, Ibrahim HIM, Khalifa A. The Halotolerant Probiotic Bacterium Enterococcus lactis ASF-2 from Al-Asfar Lake, Saudi Arabia, Reduces Inflammation in Carrageenan-Induced Paw Edema. Microorganisms 2023; 11:2415. [PMID: 37894072 PMCID: PMC10609640 DOI: 10.3390/microorganisms11102415] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/17/2023] [Accepted: 09/23/2023] [Indexed: 10/29/2023] Open
Abstract
Inflammation-related diseases are major causes of mortality and disability worldwide. This study aimed to identify and investigate probiotic bacteria that could be present in Al-Asfar Lake in Al-Ahsa City, Saudi Arabia to prevent the inflammatory responses of carrageenan-induced paw edema. In total, seven active strains were isolated, and three isolates (ASF-1, ASF-2, and ASF-3) exhibited a positive Gram stain and viable growth at 20% NaCl salinity; they also lacked catalase and hemolytic activities and had high levels of cell surface hydrophobicity (CSH). They also demonstrated potent antibacterial activity against Salmonella typhi and Staphylococcus aureus. These results revealed that ASF-2 had probiotic qualities, and it was selected for further research. ASF-2 demonstrated significant anti-inflammatory effects in an experimental model of carrageenan-induced paw edema; the experimental model showed decreased levels of pro-inflammatory markers, such as interleukin 6 (IL-6), interleukin 17 (IL-17), and transforming growth factor-β (TGF-β), and an increased level of an anti-inflammatory marker (interferon gamma (IFN-γ)). Animals in the control group saw a 45% decrease in edema when compared to mice in the carrageenan group. When comparing tissue damage and infiltration in the ASF-2-treated and non-treated mice, the histological examination of the sub-planar tissues of the hind leg revealed that the inflamed tissues had healed. The 16S rRNA sequencing method was utilized to establish that ASF-2 is, in fact, Enterococcus lactis with a 99.2% sequence similarity. These findings shed further light on ASF-2's potential as a biocompatible anti-inflammatory medication.
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Affiliation(s)
- Najla Alsaud
- AlNukhba Modern Schools, Al-Ahsa 31982, Saudi Arabia
| | | | | | | | | | - Jihad Alessa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Abeer Almousa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Hairul Islam M. Ibrahim
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Molecular Biology Division, Pondicherry Centre for Biological Sciences and Educational Trust, Pondicherry 605004, India
| | - Ashraf Khalifa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt
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Khalifa A, Ibrahim HIM, Sheikh A, Khalil HE. Attenuation of Immunogenicity in MOG-Induced Oligodendrocytes by the Probiotic Bacterium Lactococcus Sp. PO3. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1731. [PMID: 37893449 PMCID: PMC10608413 DOI: 10.3390/medicina59101731] [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: 08/24/2023] [Revised: 09/14/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023]
Abstract
Background and Objectives: Milk is healthy and includes several vital nutrients and microbiomes. Probiotics in milk and their derivatives modulate the immune system, fight inflammation, and protect against numerous diseases. The present study aimed to isolate novel bacterial species with probiotic potential for neuroinflammation. Materials and Methods: Six milk samples were collected from lactating dairy cows. Bacterial isolates were obtained using standard methods and were evaluated based on probiotic characteristics such as the catalase test, hemolysis, acid/bile tolerance, cell adhesion, and hydrophobicity, as well as in vitro screening. Results: Nine morphologically diverse bacterial isolates were found in six different types of cow's milk. Among the isolates, PO3 displayed probiotic characteristics. PO3 was a Gram-positive rod cell that grew in an acidic (pH-2) salty medium containing bile salt and salinity (8% NaCl). PO3 also exhibited substantial hydrophobicity and cell adhesion. The sequencing comparison of the 16S rRNA genes revealed that PO3 was Lactococcus raffinolactis with a similarity score of 99.3%. Furthermore, PO3 was assessed for its neuroanti-inflammatory activity on human oligodendrocyte (HOG) cell lines using four different neuroimmune markers: signal transducer and activator of transcription (STAT-3), myelin basic protein (MBP), glial fibrillary acidic protein (GFAP), and GLAC in HOG cell lines induced by MOG. Unlike the rest of the evaluated neuroimmune markers, STAT-3 levels were elevated in the MOG-treated HOG cell lines compared to the untreated ones. The expression level of STAT-3 was attenuated in both PO3-MOG-treated and only PO3-treated cell lines. On the contrary, in PO3-treated cell lines, MBP, GFAP, and GLAC were significantly expressed at higher levels when compared with the MOG-treated cell lines. Conclusions: The findings reported in this article are to be used as a foundation for further in vivo research in order to pave the way for the possible use of probiotics in the treatment of neuroinflammatory diseases, including multiple sclerosis.
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Affiliation(s)
- Ashraf Khalifa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Hairul-Islam Mohamed Ibrahim
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Molecular Biology Division, Pondicherry Centre for Biological Sciences and Educational Trust, Pondicherry 605004, India
| | - Abdullah Sheikh
- Camel Research Center, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
| | - Hany Ezzat Khalil
- Department of Pharmaceutical Sciences, College of Clinical Pharmacy, King Faisal University, Al-Ahsa 31982, Saudi Arabia
- Department of Pharmacognosy, Faculty of Pharmacy, Minia University, Minia 61519, Egypt
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Khalifa A, Ibrahim HIM, Sheikh A. Bacillus subtilis PM5 from Camel Milk Boosts Chicken Immunity and Abrogates Salmonella entertitidis Infections. Microorganisms 2023; 11:1719. [PMID: 37512891 PMCID: PMC10385966 DOI: 10.3390/microorganisms11071719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 06/15/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023] Open
Abstract
With the practice of a successful livestock industry using antibiotics, which has continued for more than five decades, researchers have long been interested in finding alternatives to antibiotics for poultry production. Probiotics can potentially reduce enteric diseases in livestock and enhance their productivity. The aim of this study was to isolate putative probiotics from camel milk and test them against Salmonella infection as well as host immune development. Thirteen different isolates were obtained from six different camel milk samples from dairy farms in Saudi Arabia. Three of the six isolates (PM1, PM2, PM3, PM4, PM5, and PM6) that showed Gram-positive characters reacted negatively to catalase and hemolytic assays. PM1, PM5, and PM6 showed significant nonpolar surface properties (>51% hydrophobic) and potent antimicrobial activities against avian pathogens, namely S. enterica, S. typhi, S. aureus, and E. coli. PM5 exhibited substantial probiotic traits; therefore, further focus was given to it. PM5 was identified as Bacillus subtilis OQ913924 by the 16S rRNA sequencing method and showed similarity matrix > 99%. An in vivo chicken model was used to access the health benefits of probiotics. After salmonella infection, the mucosal immune response was significantly increased (p < 0.01), and none of the challenge protocols caused mortality or clinical symptoms after infection in intestinal contents. S. enterica organ infiltration in the spleen, thymus, and small intestine was significantly reduced in the B. subtilis PM5-fed chickens. The S. enterica load in chicken feces was reduced from CFU 7.2 to 5.2 in oral-fed B. subtilis PM5-fed chickens. Probiotic-fed chickens showed buffered intestinal content and positively regulated the level of butyric acid (p < 0.05), and intestinal interleukin 1 beta (IL1-β), C-reactive protein (CRP), and interferon gamma (IFN-γ) levels were reduced (p < 0.05). In addition, B. subtilis PM5 showed significant binding to peritoneal macrophages cells and inhibited S. enterica surface adhesion, indicating co-aggregation of B. subtilis PM5 in macrophage cells. It could be concluded that supplementation with probiotics can improve the growth performance of broilers and the quality of broiler chickens against enteric pathogens. The introduction of this probiotic into the commercial poultry feed market in the near future may assist in narrowing the gap that now exists between chicken breeding and consumer demand.
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Affiliation(s)
- Ashraf Khalifa
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Botany and Microbiology Department, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Hairul-Islam Mohamed Ibrahim
- Biological Science Department, College of Science, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
- Molecular Biology Division, Pondicherry Centre for Biological Sciences and Educational Trust, Pondicherry 605004, India
| | - Abdullah Sheikh
- Camel Research Center, King Faisal University, P.O. Box 400, Al-Ahsa 31982, Saudi Arabia
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Shakya AK, Mallick B, Nandakumar KS. A Perspective on Oral Immunotherapeutic Tools and Strategies for Autoimmune Disorders. Vaccines (Basel) 2023; 11:1031. [PMID: 37376420 DOI: 10.3390/vaccines11061031] [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: 02/25/2023] [Revised: 05/19/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
Oral immune tolerance is a physiological process to achieve tolerance against autoimmunity by oral ingestion of self-antigen(s) or other therapeutics. At the cellular level, oral tolerance suppresses autoimmune diseases by activating FoxP-positive and -negative regulatory T cells (Tregs) and/or causing clonal anergy or deletion of autoreactive T cells, affecting B cell tolerance. However, oral delivery of antigens/biologics is challenging due to their instability in the harsh environment of the gastrointestinal (GI) tract. Several antigen/drug delivery tools and approaches, including micro/nanoparticles and transgenic plant-based delivery systems, have been explored to demonstrate oral immune tolerance for different autoimmune diseases successfully. However, despite the effectiveness, variation in results, dose optimization, and undesirable immune system activation are the limitations of the oral approach to further advancement. From this perspective, the current review discusses the oral tolerance phenomenon, cellular mechanisms, antigen delivery tools and strategies, and its challenges.
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Affiliation(s)
| | - Buddhadev Mallick
- Department of Zoology, Raniganj Girls College, Bardhaman 713358, West Bengal, India
| | - Kutty Selva Nandakumar
- Department of Environmental and Biosciences, School of Business, Innovation, and Sustainability, Halmstad University, 301 18 Halmstad, Sweden
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