1
|
Basu S, Talluri RA, Kelgaonkar A. Tubercular Retinitis and Retinal Vasculitis: Manifestations of a Shared Disease Spectrum. Ocul Immunol Inflamm 2025:1-13. [PMID: 40347454 DOI: 10.1080/09273948.2025.2501737] [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: 03/21/2025] [Revised: 04/25/2025] [Accepted: 04/29/2025] [Indexed: 05/14/2025]
Abstract
Isolated retinal involvement in ocular tuberculosis (TB) is not well understood and remains largely underreported. TB retinal lesions can be classified into two broad categories: retinal vasculitis and isolated retinal granuloma. TB retinal vasculitis is the more recognized phenotype and may present with perivascular infiltrates alone or alongside other ocular signs such as subvascular lesions, focal vascular tortuosity, and occlusive vasculitis. These additional signs are crucial for diagnosing TB retinal vasculitis in TB-endemic regions. However, isolated retinal granulomas due to TB are rarely documented and poorly characterized. In this review, we have described the various clinical phenotypes of retinal TB, including a multimodal overview of an isolated intraretinal granuloma. We propose that TB retinitis and retinal vasculitis are part of a disease continuum of retinal TB. To support our hypothesis regarding retinal TB, we draw inferences from historical data derived from histopathological examinations of the eye as well as clinical and experimental studies on cerebral TB vasculitis. We have also reviewed other sites of TB vasculitis, such as the skin and major vessels, including the aorta. Understanding TB vasculitis in the brain and other organs could potentially elucidate not only the pathogenesis of retinal TB but also the diagnosis and management of this condition.
Collapse
Affiliation(s)
- Soumyava Basu
- Saroja A Rao Centre for Uveitis, LV Prasad Eye Institute, Hyderabad, India
| | | | - Anup Kelgaonkar
- Uveitis Service, LV Prasad Eye Institute, Vijayawada, India
- Uveitis and Retina Services, LV Prasad Eye Institute, Bhubaneswar, India
| |
Collapse
|
2
|
Abil OZ, Liu S, Yeh YW, Wu Y, Sen Chaudhuri A, Li NS, Deng C, Xiang Z. A mucosal vaccine formulation against tuberculosis by exploiting the adjuvant activity of S100A4-A damage-associated molecular pattern molecule. Vaccine 2024; 42:126151. [PMID: 39089961 DOI: 10.1016/j.vaccine.2024.07.052] [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: 03/11/2024] [Revised: 06/28/2024] [Accepted: 07/15/2024] [Indexed: 08/04/2024]
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), remains one of the top three causes of death. Currently, the only licensed vaccine against TB is the bacillus Calmette-Guerin (BCG), which lacks efficacy in preventing and controlling pulmonary TB in adults. We aimed to evaluate a nasal TB vaccine formulation composed of the Mtb-specific vaccine antigen ESAT-6, an Mtb-associated protein that can trigger protective immune responses, and S100A4, a recently characterized novel mucosal adjuvant. Mice were intranasally given recombinant ESAT-6 in the presence or absence of S100A4 as an adjuvant. We have provided experimental evidence demonstrating that S100A4 admixed to ESAT-6 could induce Mtb-specific adaptive immune responses after intranasal immunization. S100A4 remarkably augmented the levels of anti-ESAT-6 IgG in serum and IgA in mucosal sites, including lung exudates, bronchoalveolar lavage fluid (BALF) and nasal lavage. Furthermore, in both lung and spleen tissues, S100A4 strongly promoted ESAT-6-specific expansion of CD4 T cells. Both CD4 and CD8 T cells from these tissues expressed increased levels of IFN-γ, TNF-α, and IL-17, cytokines critical for antimicrobial activity. Antigen-reencounter-induced T cell proliferative responses, a key vaccine performance indicator, were augmented in the spleen of S100A4-adjuvanted mice. Furthermore, CD8 T cells from the spleen and lung tissues of these mice expressed higher levels of granzyme B upon antigen re-stimulation. S100A4-adjuvanted immunization may predict good mucosal protection against TB.
Collapse
Affiliation(s)
- Olifan Zewdie Abil
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Shuwei Liu
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yu-Wen Yeh
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Yuxuan Wu
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Arka Sen Chaudhuri
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Nga Shan Li
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Chujun Deng
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China
| | - Zou Xiang
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong, China.
| |
Collapse
|
3
|
Zang X, Zhang J, Jiang Y, Feng T, Cui Y, Wang H, Cui Z, Dang G, Liu S. Serine protease Rv2569c facilitates transmission of Mycobacterium tuberculosis via disrupting the epithelial barrier by cleaving E-cadherin. PLoS Pathog 2024; 20:e1012214. [PMID: 38722857 PMCID: PMC11081392 DOI: 10.1371/journal.ppat.1012214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
Epithelial cells function as the primary line of defense against invading pathogens. However, bacterial pathogens possess the ability to compromise this barrier and facilitate the transmigration of bacteria. Nonetheless, the specific molecular mechanism employed by Mycobacterium tuberculosis (M.tb) in this process is not fully understood. Here, we investigated the role of Rv2569c in M.tb translocation by assessing its ability to cleave E-cadherin, a crucial component of cell-cell adhesion junctions that are disrupted during bacterial invasion. By utilizing recombinant Rv2569c expressed in Escherichia coli and subsequently purified through affinity chromatography, we demonstrated that Rv2569c exhibited cell wall-associated serine protease activity. Furthermore, Rv2569c was capable of degrading a range of protein substrates, including casein, fibrinogen, fibronectin, and E-cadherin. We also determined that the optimal conditions for the protease activity of Rv2569c occurred at a temperature of 37°C and a pH of 9.0, in the presence of MgCl2. To investigate the function of Rv2569c in M.tb, a deletion mutant of Rv2569c and its complemented strains were generated and used to infect A549 cells and mice. The results of the A549-cell infection experiments revealed that Rv2569c had the ability to cleave E-cadherin and facilitate the transmigration of M.tb through polarized A549 epithelial cell layers. Furthermore, in vivo infection assays demonstrated that Rv2569c could disrupt E-cadherin, enhance the colonization of M.tb, and induce pathological damage in the lungs of C57BL/6 mice. Collectively, these results strongly suggest that M.tb employs the serine protease Rv2569c to disrupt epithelial defenses and facilitate its systemic dissemination by crossing the epithelial barrier.
Collapse
Affiliation(s)
- Xinxin Zang
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Jiajun Zhang
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Yanyan Jiang
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Tingting Feng
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Yingying Cui
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Hui Wang
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Ziyin Cui
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Guanghui Dang
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| | - Siguo Liu
- State Key Laboratory for Animal Disease Control and Prevention, Division of Bacterial Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, PR China
| |
Collapse
|
4
|
Mitchell JL, MacDougall L, Dobromylskyj MJ, Smith K, Stavinohova R, Gunn-Moore DA, Hope JC, Scurrell E. Ocular mycobacterial lesions in cats. Vet Pathol 2022; 59:792-805. [PMID: 35587045 PMCID: PMC9358306 DOI: 10.1177/03009858221098431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ocular mycobacterial infections are an under-recognized cause of morbidity in the
domestic cat. This study aimed to explore the distribution, histopathological
appearance, and severity of feline ocular mycobacterial lesions, and to
characterize the immune cell population with immunohistochemistry. Routine
histological staining with hematoxylin and eosin, and Masson’s trichrome, was
performed to identify ocular lesions and assign an inflammation score based on
the number of cells present. Acid-fast bacilli were detected with Ziehl-Neelsen,
and immunohistochemistry for ionized calcium-binding adaptor protein-1 (Iba1),
calprotectin, cluster of differentiation 3 (CD3), and Pax5 was undertaken on
formalin-fixed paraffin-embedded tissue samples from 24 cases of ocular
mycobacteriosis. Posterior or panuveitis with concurrent retinitis was
identified in 20/24 cases (83%), with retinal detachment in 16/20 (80%) of these
cases. Choroidal lesions had the highest median inflammation score.
Ziehl-Neelsen-positive organisms were detected in 20/24 cases (83%), with the
highest prevalence of acid-fast bacilli detected in choroidal lesions (16/20,
80%). Lesions were typically granulomatous to pyogranulomatous, characterized by
abundant numbers of Iba1-positive macrophages, followed by calprotectin-positive
granulocytes and monocytes, fewer T cells, and rarer B cells. However, where
iritis was identified, inflammation was typically lymphoplasmacytic (11/16
cases, 69%). Where diagnostic testing was performed, tuberculosis (ie, infection
with Mycobacterium bovis, Mycobacterium
microti, or a nonspeciated Mycobacterium
tuberculosis-complex pathogen) was diagnosed in 20/22 cats (91%),
with Mycobacterium lepraemurium infection identified in the
other 2/22 cats (9%). These results suggest the choroid is the primary site of
lesion development in most cases of feline ocular mycobacteriosis, and
inflammatory changes are associated with the presence of mycobacteria localized
to ocular tissues.
Collapse
Affiliation(s)
| | | | | | - Ken Smith
- Royal Veterinary College, Hatfield, UK
| | | | | | | | | |
Collapse
|
5
|
de Waal AM, Hiemstra PS, Ottenhoff TH, Joosten SA, van der Does AM. Lung epithelial cells interact with immune cells and bacteria to shape the microenvironment in tuberculosis. Thorax 2022; 77:408-416. [PMID: 35017314 PMCID: PMC8938665 DOI: 10.1136/thoraxjnl-2021-217997] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 12/16/2021] [Indexed: 12/31/2022]
Abstract
The lung epithelium has long been overlooked as a key player in tuberculosis disease. In addition to acting as a direct barrier to Mycobacterium tuberculosis (Mtb), epithelial cells (EC) of the airways and alveoli act as first responders during Mtb infections; they directly sense and respond to Mtb by producing mediators such as cytokines, chemokines and antimicrobials. Interactions of EC with innate and adaptive immune cells further shape the immune response against Mtb. These three essential components, epithelium, immune cells and Mtb, are rarely studied in conjunction, owing in part to difficulties in coculturing them. Recent advances in cell culture technologies offer the opportunity to model the lung microenvironment more closely. Herein, we discuss the interplay between lung EC, immune cells and Mtb and argue that modelling these interactions is of key importance to unravel early events during Mtb infection.
Collapse
Affiliation(s)
- Amy M de Waal
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Pieter S Hiemstra
- Department of Pulmonology, Leiden University Medical Center, Leiden, The Netherlands
| | - Tom Hm Ottenhoff
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Simone A Joosten
- Department of Infectious Diseases, Leiden University Medical Center, Leiden, The Netherlands
| | - Anne M van der Does
- Department of Pulmonology, Leiden University Medical Center, Leiden, The Netherlands
| |
Collapse
|
6
|
Affinity of Mycobacterium tuberculosis strains for M059K microglial cells after migration through A549 alveolar epithelium. Eur J Clin Microbiol Infect Dis 2021; 40:1881-1889. [PMID: 33834319 DOI: 10.1007/s10096-021-04226-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 03/14/2021] [Indexed: 10/21/2022]
Abstract
Tuberculosis (TB) remains a major threat worldwide while central nervous system TB (CNS-TB) is one of the most severe forms of extrapulmonary TB. CNS-TB develops as a secondary infection during the hematogenous spread of Mycobacterium tuberculosis (M. tuberculosis) from the lungs to the CNS. Factors influencing the dissemination of the bacilli to the CNS have not been studied extensively. This study evaluated the transmigration ability through the alveolar epithelium and adhesion and invasion capacity of glial cells of M. tuberculosis strains of varying drug susceptibility and genotype profiles using an in vitro co-culture model. A549 alveolar epithelial cells and M059K glial cells were co-cultured in a Transwell plate with A549 cells cultured in the upper chamber and M059K glial cells in the lower chamber. A549 epithelial cells were infected with F15/LAM4/KZN (susceptible, MDR, XDR), Beijing (susceptible, XDR), F11 (susceptible), F28 (MDR), and H37Rv strains of M. tuberculosis. The transmigration of an A549 monolayer and subsequent adhesion and invasion rates of M059K cells were established. The susceptible and XDR variants of the F15/LAM4/KZN strain transmigrate the alveolar epithelial cell monolayer more efficiently than the MDR variant. The Beijing-XDR variant showed a high transmigration rate, while the susceptible variant showed no transmigration ability. Similar to the MDR F15/LAM4/KZN, the F28 and F11 strains showed a low dissemination ability. The bacteria were still capable to adhere to M059K glial cells after passage through the A549 cells. We conclude that M. tuberculosis isolates that passed through a monolayer of A549 alveolar epithelium by transcellular migration can still adhere to M059K glial cells. There is no genetic link between resistance and transmigration.
Collapse
|
7
|
Moule MG, Cirillo JD. Mycobacterium tuberculosis Dissemination Plays a Critical Role in Pathogenesis. Front Cell Infect Microbiol 2020; 10:65. [PMID: 32161724 PMCID: PMC7053427 DOI: 10.3389/fcimb.2020.00065] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 02/07/2020] [Indexed: 12/27/2022] Open
Abstract
Mycobacterium tuberculosis is primarily a respiratory pathogen. However, 15% of infections worldwide occur at extrapulmonary sites causing additional complications for diagnosis and treatment of the disease. In addition, dissemination of M. tuberculosis out of the lungs is thought to be more than just a rare event leading to extrapulmonary tuberculosis, but rather a prerequisite step that occurs during all infections, producing secondary lesions that can become latent or productive. In this review we will cover the clinical range of extrapulmonary infections and the process of dissemination including evidence from both historical medical literature and animal experiments for dissemination and subsequent reseeding of the lungs through the lymphatic and circulatory systems. While the mechanisms of M. tuberculosis dissemination are not fully understood, we will discuss the various models that have been proposed to address how this process may occur and summarize the bacterial virulence factors that facilitate M. tuberculosis dissemination.
Collapse
Affiliation(s)
- Madeleine G. Moule
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Jeffrey D. Cirillo
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX, United States
| |
Collapse
|
8
|
Waters R, Ndengane M, Abrahams MR, Diedrich CR, Wilkinson RJ, Coussens AK. The Mtb-HIV syndemic interaction: why treating M. tuberculosis infection may be crucial for HIV-1 eradication. Future Virol 2020; 15:101-125. [PMID: 32273900 PMCID: PMC7132588 DOI: 10.2217/fvl-2019-0069] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Accelerated tuberculosis and AIDS progression seen in HIV-1 and Mycobacterium tuberculosis (Mtb)-coinfected individuals indicates the important interaction between these syndemic pathogens. The immunological interaction between HIV-1 and Mtb has been largely defined by how the virus exacerbates tuberculosis disease pathogenesis. Understanding of the mechanisms by which pre-existing or subsequent Mtb infection may favor the replication, persistence and progression of HIV, is less characterized. We present a rationale for the critical consideration of ‘latent’ Mtb infection in HIV-1 prevention and cure strategies. In support of this position, we review evidence of the effect of Mtb infection on HIV-1 acquisition, replication and persistence. We propose that ‘latent’ Mtb infection may have considerable impact on HIV-1 pathogenesis and the continuing HIV-1 epidemic in sub-Saharan Africa.
Collapse
Affiliation(s)
- Robyn Waters
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Medicine, University of Cape Town, Observatory 7925, WC, South Africa
| | - Mthawelanga Ndengane
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Pathology, University of Cape Town, Observatory 7925, WC, South Africa
| | - Melissa-Rose Abrahams
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Pathology, University of Cape Town, Observatory 7925, WC, South Africa
| | - Collin R Diedrich
- Department of Pediatrics, Children's Hospital of Pittsburgh of the University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Robert J Wilkinson
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Infectious Diseases, Imperial College London, London W2 1PG, United Kingdom.,The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Anna K Coussens
- Wellcome Centre for Infectious Diseases Research in Africa, Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Observatory 7925, WC, South Africa.,Department of Pathology, University of Cape Town, Observatory 7925, WC, South Africa.,Infectious Diseases and Immune Defence Division, The Walter & Eliza Hall Institute of Medical Research, Parkville 3279, VIC, Australia.,Division of Medical Biology, Faculty of Medicine, Dentistry & Health Sciences, University of Melbourne, Parkville 3279, VIC, Australia
| |
Collapse
|
9
|
Ryndak MB, Laal S. Mycobacterium tuberculosis Primary Infection and Dissemination: A Critical Role for Alveolar Epithelial Cells. Front Cell Infect Microbiol 2019; 9:299. [PMID: 31497538 PMCID: PMC6712944 DOI: 10.3389/fcimb.2019.00299] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/02/2019] [Indexed: 12/28/2022] Open
Abstract
Globally, tuberculosis (TB) has reemerged as a major cause of morbidity and mortality, despite the use of the Mycobacterium bovis BCG vaccine and intensive attempts to improve upon BCG or develop new vaccines. Two lacunae in our understanding of the Mycobacterium tuberculosis (M. tb)-host pathogenesis have mitigated the vaccine efforts; the bacterial-host interaction that enables successful establishment of primary infection and the correlates of protection against TB. The vast majority of vaccine efforts are based on the premise that cell-mediated immunity (CMI) is the predominating mode of protection against TB. However, studies in animal models and in humans demonstrate that post-infection, a period of several weeks precedes the initiation of CMI during which the few inhaled bacteria replicate dramatically and disseminate systemically. The “Trojan Horse” mechanism, wherein M. tb is phagocytosed and transported across the alveolar barrier by infected alveolar macrophages has been long postulated as the sole, primary M. tb:host interaction. In the current review, we present evidence from our studies of transcriptional profiles of M. tb in sputum as it emerges from infectious patients where the bacteria are in a quiescent state, to its adaptations in alveolar epithelial cells where the bacteria transform to a highly replicative and invasive phenotype, to its maintenance of the invasive phenotype in whole blood to the downregulation of invasiveness upon infection of epithelial cells at an extrapulmonary site. Evidence for this alternative mode of infection and dissemination during primary infection is supported by in vivo, in vitro cell-based, and transcriptional studies from multiple investigators in recent years. The proposed alternative mechanism of primary infection and dissemination across the alveolar barrier parallels our understanding of infection and dissemination of other Gram-positive pathogens across their relevant mucosal barriers in that barrier-specific adhesins, toxins, and enzymes synergize to facilitate systemic establishment of infection prior to the emergence of CMI. Further exploration of this M. tb:non-phagocytic cell interaction can provide alternative approaches to vaccine design to prevent infection with M. tb and not only decrease clinical disease but also decrease the overwhelming reservoir of latent TB infection.
Collapse
Affiliation(s)
- Michelle B Ryndak
- Department of Pathology, New York University School of Medicine, New York, NY, United States
| | - Suman Laal
- Department of Pathology, New York University School of Medicine, New York, NY, United States
| |
Collapse
|
10
|
Afinjuomo F, Barclay TG, Parikh A, Song Y, Chung R, Wang L, Liu L, Hayball JD, Petrovsky N, Garg S. Design and Characterization of Inulin Conjugate for Improved Intracellular and Targeted Delivery of Pyrazinoic Acid to Monocytes. Pharmaceutics 2019; 11:E243. [PMID: 31121836 PMCID: PMC6572292 DOI: 10.3390/pharmaceutics11050243] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/10/2019] [Accepted: 05/16/2019] [Indexed: 11/16/2022] Open
Abstract
The propensity of monocytes to migrate into sites of mycobacterium tuberculosis (TB) infection and then become infected themselves makes them potential targets for delivery of drugs intracellularly to the tubercle bacilli reservoir. Conventional TB drugs are less effective because of poor intracellular delivery to this bacterial sanctuary. This study highlights the potential of using semicrystalline delta inulin particles that are readily internalised by monocytes for a monocyte-based drug delivery system. Pyrazinoic acid was successfully attached covalently to the delta inulin particles via a labile linker. The formation of new conjugate and amide bond was confirmed using zeta potential, Proton Nuclear Magnetic Resonance (1HNMR) and Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) confirmed that no significant change in size after conjugation which is an important parameter for monocyte targeting. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to establish the change in thermal properties. The analysis of in-vitro release demonstrated pH-triggered drug cleavage off the delta inulin particles that followed a first-order kinetic process. The efficient targeting ability of the conjugate for RAW 264.7 monocytic cells was supported by cellular uptake studies. Overall, our finding confirmed that semicrystalline delta inulin particles (MPI) can be modified covalently with drugs and such conjugates allow intracellular drug delivery and uptake into monocytes, making this system potentially useful for the treatment of TB.
Collapse
Affiliation(s)
- Franklin Afinjuomo
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Thomas G Barclay
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Ankit Parikh
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Yunmei Song
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Rosa Chung
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Lixin Wang
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Liang Liu
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - John D Hayball
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| | - Nikolai Petrovsky
- Vaxine Pty. Ltd., Adelaide, SA 5042, Australia.
- Department of Endocrinology, Flinders University, Adelaide, SA 5042, Australia.
| | - Sanjay Garg
- School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA 5001, Australia.
| |
Collapse
|
11
|
Hasan S, Sebo P, Osicka R. A guide to polarized airway epithelial models for studies of host-pathogen interactions. FEBS J 2018; 285:4343-4358. [PMID: 29896776 DOI: 10.1111/febs.14582] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/21/2018] [Accepted: 06/11/2018] [Indexed: 11/28/2022]
Abstract
Mammalian lungs are organs exhibiting the cellular and spatial complexity required for gas exchange to support life. The respiratory epithelium internally lining the airways is susceptible to infections due to constant exposure to inhaled microbes. Biomedical research into respiratory bacterial infections in humans has been mostly carried out using small mammalian animal models or two-dimensional, submerged cultures of undifferentiated epithelial cells. These experimental model systems have considerable limitations due to host specificity of bacterial pathogens and lack of cellular and morphological complexity. This review describes the in vitro differentiated and polarized airway epithelial cells of human origin that are used as a model to study respiratory bacterial infections. Overall, these models recapitulate key aspects of the complexity observed in vivo and can help in elucidating the molecular details of disease processes observed during respiratory bacterial infections.
Collapse
Affiliation(s)
- Shakir Hasan
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Peter Sebo
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| | - Radim Osicka
- Institute of Microbiology of the CAS, v. v. i., Prague, Czech Republic
| |
Collapse
|