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Abdel-Razek O, Audlin J, Poe DS, Wang G. Surfactant proteins and innate immunity of otitis media. Innate Immun 2022; 28:213-223. [PMID: 36069032 PMCID: PMC9900255 DOI: 10.1177/17534259221123309] [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: 01/09/2023] Open
Abstract
Otitis media (OM) is the most common disease among young children and one of the most frequent reasons to visit the pediatrician. Development of OM requires nasopharyngeal colonization by a pathogen which must gain access to the tympanic cavity through the eustachian tube (ET) along with being able to overcome the defense mechanisms of the immune system and middle ear mucosa. OM can be caused by viral or bacterial infection. The three main bacterial pathogens are Streptococcus pneumoniae, nontypeable Haemophilus influenzae (NTHi), and Moraxella catarrhalis. Innate immunity is important in OM resolution as the disease occurs in very young children before the development of specific immunity. Elements of innate immunity include natural barriers and pattern recognition receptors such as Toll like receptors (TLRs), and Nod like receptors (NLRs). Surfactant proteins A (SP-A) and D (SP-D) act as pattern recognition receptors and are found in the lung and many other tissues including the ET and the middle ear where they probably function in host defense. Surfactant has a potential for use in the treatment of OM due to surface tension lowering function in the ET, and the possible immune functions of SP-D and SP-A in the middle ear and ET.
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Affiliation(s)
- Osama Abdel-Razek
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA,Guirong Wang, Department of Surgery, UH Room 8715, SUNY Upstate Medical University, 750 E Adams St, Syracuse, NY, 13210, USA.
| | - Jason Audlin
- Department of Otolaryngology, SUNY Upstate Medical University, Syracuse, NY, USA
| | | | - Guirong Wang
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA,Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, NY, USA
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Toll-Like Receptors: Expression and Roles in Otitis Media. Int J Mol Sci 2021; 22:ijms22157868. [PMID: 34360632 PMCID: PMC8346131 DOI: 10.3390/ijms22157868] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/13/2021] [Accepted: 07/19/2021] [Indexed: 12/12/2022] Open
Abstract
Otitis media is mainly caused by upper respiratory tract infection and eustachian tube dysfunction. If external upper respiratory tract infection is not detected early in the middle ear, or an appropriate immune response does not occur, otitis media can become a chronic state or complications may occur. Therefore, given the important role of Toll-like receptors (TLRs) in the early response to external antigens, we surveyed the role of TLRs in otitis media. To summarize the role of TLR in otitis media, we reviewed articles on the expression of TLRs in acute otitis media (AOM), otitis media with effusion (OME), chronic otitis media (COM) with cholesteatoma, and COM without cholesteatoma. Many studies showed that TLRs 1–10 are expressed in AOM, OME, COM with cholesteatoma, and COM without cholesteatoma. TLR expression in the normal middle ear mucosa is absent or weak, but is increased in inflammatory fluid of AOM, effusion of OME, and granulation tissue and cholesteatoma of COM. In addition, TLRs show increased or decreased expression depending on the presence or absence of bacteria, recurrence of disease, tissue type, and repeated surgery. In conclusion, expression of TLRs is associated with otitis media. Inappropriate TLR expression, or delayed or absent induction, are associated with the occurrence, recurrence, chronicization, and complications of otitis media. Therefore, TLRs are very important in otitis media and closely related to its etiology.
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Abdel-Razek O, Liu T, Chen X, Wang Q, Vanga G, Wang G. Role of Surfactant Protein D in Experimental Otitis Media. J Innate Immun 2021; 13:197-210. [PMID: 33556949 DOI: 10.1159/000513605] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 12/01/2020] [Indexed: 11/19/2022] Open
Abstract
Surfactant protein D (SP-D) is a C-type collectin and plays an important role in innate immunity and homeostasis in the lung. This study studied SP-D role in the nontypeable Haemophilus influenzae (NTHi)-induced otitis media (OM) mouse model. Wild-type C57BL/6 (WT) and SP-D knockout (KO) mice were used in this study. Mice were injected in the middle ear (ME) with 5 μL of NTHi bacterial solution (3.5 × 105 CFU/ear) or with the same volume of sterile saline (control). Mice were sacrificed at 3 time points, days 1, 3, and 7, after treatment. We found SP-D expression in the Eustachian tube (ET) and ME mucosa of WT mice but not in SP-D KO mice. After infection, SP-D KO mice showed more intense inflammatory changes evidenced by the increased mucosal thickness and inflammatory cell infiltration in the ME and ET compared to WT mice (p < 0.05). Increased bacterial colony-forming units and cytokine (IL-6 and IL-1β) levels in the ear washing fluid of infected SP-D KO mice were compared to infected WT mice. Molecular analysis revealed higher levels of NF-κB and NLRP3 activation in infected SP-D KO compared to WT mice (p < 0.05). In vitro studies demonstrated that SP-D significantly induced NTHi bacterial aggregation and enhanced bacterial phagocytosis by macrophages (p < 0.05). Furthermore, human ME epithelial cells showed a dose-dependent increased expression of NLRP3 and SP-D proteins after LPS treatment. We conclude that SP-D plays a critical role in innate immunity and disease resolution through enhancing host defense and regulating inflammatory NF-κB and NLRP3 activation in experimental OM mice.
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Affiliation(s)
- Osama Abdel-Razek
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Tianyi Liu
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Xinghua Chen
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Qiushi Wang
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Gautam Vanga
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Guirong Wang
- Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA, .,Department of Microbiology and Immunology, SUNY Upstate Medical University, Syracuse, New York, USA,
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Thorenoor N, Kawasawa YI, Gandhi CK, Zhang X, Floros J. Differential Impact of Co-expressed SP-A1/SP-A2 Protein on AM miRNome; Sex Differences. Front Immunol 2019; 10:1960. [PMID: 31475015 PMCID: PMC6707024 DOI: 10.3389/fimmu.2019.01960] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/02/2019] [Indexed: 12/04/2022] Open
Abstract
In humans there are two surfactant protein A (SP-A) functional genes SFTPA1 and SFTPA2 encoding innate immune molecules, SP-A1 and SP-A2, respectively, with numerous genetic variants each. SP-A interacts and regulates many of the functions of alveolar macrophages (AM). It is shown that SP-A variants differ in their ability to regulate the AM miRNome in response to oxidative stress (OxS). Because humans have both SP-A gene products, we were interested to determine the combined effect of co-expressed SP-A1/SP-A2 (co-ex) in response to ozone (O3) induced OxS on AM miRNome. Human transgenic (hTG) mice, carrying both SP-A1/SP-A2 (6A2/1A0, co-ex) and SP-A- KO were utilized. The hTG and KO mice were exposed to filtered air (FA) or O3 and miRNA levels were measured after AM isolation with or without normalization to KO. We found: (i) The AM miRNome of co-ex males and females in response to OxS to be largely downregulated after normalization to KO, but after Bonferroni multiple comparison analysis only in females the AM miRNome remained significantly different compared to control (FA); (ii) The targets of the significantly changed miRNAs were downregulated in females and upregulated in males; (iii) Several of the validated mRNA targets were involved in pro-inflammatory response, anti-apoptosis, cell cycle, cellular growth and proliferation; (iv) The AM of SP-A2 male, shown, previously to have major effect on the male AM miRNome in response to OxS, shared similarities with the co-ex, namely in pathways involved in the pro-inflammatory response and anti-apoptosis but also exhibited differences with the cell-cycle, growth, and proliferation pathway being involved in co-ex and ROS homeostasis in SP-A2 male. We speculate that the presence of both gene products vs. single gene products differentially impact the AM responses in males and females in response to OxS.
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Affiliation(s)
- Nithyananda Thorenoor
- Department of Pediatrics, Center for Host Defense, Inflammation, and Lung Disease Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Yuka Imamura Kawasawa
- Departments of Pharmacology and Biochemistry and Molecular Biology, Institute for Personalized Medicine, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Chintan K Gandhi
- Department of Pediatrics, Center for Host Defense, Inflammation, and Lung Disease Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Xuesheng Zhang
- Department of Pediatrics, Center for Host Defense, Inflammation, and Lung Disease Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Joanna Floros
- Department of Pediatrics, Center for Host Defense, Inflammation, and Lung Disease Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States.,Department of Obstetrics and Gynecology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
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Abdel-Razek O, Ni L, Yang F, Wang G. Innate immunity of surfactant protein A in experimental otitis media. Innate Immun 2019; 25:391-400. [PMID: 31378117 PMCID: PMC6900641 DOI: 10.1177/1753425919866006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Surfactant protein A (SP-A) plays an important role in innate immune response and host defense against various microorganisms through opsonization and complement activation. To investigate the role of SP-A in non-typeable Haemophilus influenzae (NTHi)-induced acute otitis media, this study used wild type C57BL/6 (WT) and SP-A knockout (KO) mice. We divided mice into an infection group in which the middle ear (ME) was injected with NTHi and a control group that received the same treatment using normal saline. Mice were sacrificed on d 1, 3, and 7 after treatment. Temporal bone samples were fixed for histological, cellular, and molecular analyses. Ear washing fluid (EWF) was collected for culture and analyses of pro-inflammatory cytokines and inflammatory cells. SP-A-mediated bacterial aggregation and killing and phagocytosis by macrophages were studied in vitro. SP-A expression was detected in the ME and Eustachian tube mucosa of WT mice but not KO mice. After infection, KO mice showed more severe inflammation evidenced by increased ME mucosal thickness and inflammatory cell infiltration and higher NF-κB activation compared to WT mice. The levels of IL-6 and IL-1β in the EWF of infected KO mice were higher compared to infected WT mice on d 1. Our studies demonstrated that SP-A mediated NTHi aggregation and killing and enhanced bacterial phagocytosis by macrophages in vitro and modulated inflammation of the ME in otitis media in vivo.
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Affiliation(s)
| | - Lan Ni
- 1 Department of Surgery, SUNY Upstate Medical University, USA
| | - Fengyong Yang
- 1 Department of Surgery, SUNY Upstate Medical University, USA
| | - Guirong Wang
- 1 Department of Surgery, SUNY Upstate Medical University, USA.,2 Department of Microbiology and Immunology, SUNY Upstate Medical University, USA
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Wang G, Umstead TM, Hu S, Mikerov AN, Phelps DS, Floros J. Differential Effects of Human SP-A1 and SP-A2 on the BAL Proteome and Signaling Pathways in Response to Klebsiella pneumoniae and Ozone Exposure. Front Immunol 2019; 10:561. [PMID: 30972061 PMCID: PMC6443908 DOI: 10.3389/fimmu.2019.00561] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 03/04/2019] [Indexed: 12/29/2022] Open
Abstract
Surfactant protein A (SP-A) plays critical roles in host defense, regulation of inflammation and surfactant metabolism in the lung. The human SP-A locus consists of two functional genes, SFTPA1 and SFTPA2 encoding surfactant proteins SP-A1 and SP-A2, respectively. Structural and functional differences exist between SP-A1 and SP-A2 in vitro and in vivo. Ozone is a major air pollutant with a negative impact on many biological processes. In this study we used humanized transgenic (hTG) SP-A1 and SP-A2 mice, and SP-A KO mice to study in vivo effects of SP-A1 and SP-A2 on the bronchoalveolar lavage (BAL) proteomic profile and associated signaling pathways in response to ozone or filtered air (FA) exposure and Klebsiella pneumoniae infection. The BAL samples were harvested 24 h after ozone (2 ppm for 3 h) or FA exposure and infection and analyzed by two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-ToF/ToF. We found: that (1) Ozone exposure, but not infection, is a major factor for increases in total BAL protein content. (2) A total of 36 proteins were identified, accounting for 89.62% of the BAL proteins resolved by the 2D-DIGE system. (3) The number of proteins in which levels were altered more than 25% following infection and FA exposure was: SP-A2 > SP-A1 > KO for male mice, and SP-A2 ≈ SP-A1 > KO for female mice. (4) The number of proteins with more than 25% increase/decrease after ozone exposure and infection was: SP-A2 > SP-A1 ≈ KO, with the majority being increases in male mice and decreases in female mice. (5) Eleven out of the 36 proteins, including annexin A5, glutathione S-transferase A4, SP-A1/SP-A2, and 14-3-3 zeta protein, exhibited significant differences among SP-A genotypes. The acute phase response (APR) that includes the NF-kB signaling pathway plays a critical role, followed by Nrf2-mediated oxidative response, and others. These associated with SP-A genotype, sex, and ozone-induced oxidative stress in response to infection. We concluded that human SP-A2 and SP-A1 exhibit differential genotype-and sex-dependent innate immune responses to microbial pathogens and/or ozone-induced oxidative stress by modulating proteomic patterns and signaling pathways in the lung.
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Affiliation(s)
- Guirong Wang
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States.,Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, United States
| | - Todd M Umstead
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Sanmei Hu
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Anatoly N Mikerov
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - David S Phelps
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States
| | - Joanna Floros
- Department of Pediatrics, Center for Host defense, Inflammation, and Lung Disease (CHILD) Research, The Pennsylvania State University College of Medicine, Hershey, PA, United States.,Department of Obstetrics and Gynecology, The Pennsylvania State University College of Medicine, Hershey, PA, United States
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Expression, Distribution, and Role of C-Type Lectin Receptors in the Human and Animal Middle Ear and Eustachian Tube: A Review. Molecules 2018; 23:molecules23040734. [PMID: 29565818 PMCID: PMC6017961 DOI: 10.3390/molecules23040734] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Revised: 03/14/2018] [Accepted: 03/21/2018] [Indexed: 11/17/2022] Open
Abstract
Otitis media (OM) is a group of inflammatory diseases of the middle ear (ME), regardless of cause or pathological mechanism. Among the molecular biological studies assessing the pathology of OM are investigations into the expression of C-type lectin receptors (CLR) in the ME and Eustachian tube (ET). To date, nine studies have evaluated CLR expression in the ME and ET. The expression of individual CLRs in mammalian ME and ET varies by species and model of OM. Assessments have shown that the patterns of CLR expression in the ME and ET vary; that CLR expression may vary by type of OM; and that the distribution and levels of expression of CLRs may depend on the presence or absence of inflammation, with variations even within the same species and same tissue. Infection of the ME and ET with various pathogens is a common cause of all types of OM, with host responses to pathogens mediated initially by the innate immune system. CLRs are important factors in the innate immune system because they act as both adhesion molecules and as pathogen recognition receptors. The expression of CLRs in OM tissues suggests that CLRs are associated with the pathogenesis of various types of OM.
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Farajzadah Sheikh A, Saki N, Roointan M, Ranjbar R, Yadyad MJ, Kaydani A, Aslani S, Babaei M, Goodarzi H. Identification of Alloiococcus otitidis, Streptococcus pneumoniae, Moraxella catarrhalis and Haemophilus influenzae in Children With Otitis Media With Effusion. Jundishapur J Microbiol 2015; 8:e17985. [PMID: 25861433 PMCID: PMC4386075 DOI: 10.5812/jjm.17985] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 11/11/2014] [Accepted: 11/20/2014] [Indexed: 01/01/2023] Open
Abstract
Background: Based on many studies, otitis media with effusion (OME) is one of the major causes of childhood hearing loss, social malformation and medical costs. The pathogenesis still remains unclear, though it is known that this complication is closely related to bacterial infections. Alloiococcus otitidis, Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis are the most common bacterial pathogens isolated from middle ear effusions (MEEs). Objectives: Due to the prevalence of OME in children, we decided to investigate bacterial agents that cause diseases such as A. otitidis, H. influenzae, S. pneumonia and M. catarrhalis in these subjects. Patients and Methods: Forty-five children between one and 15 years of age were selected for this study. Seventy specimens were collected from MEE by myringotomy and inoculated in PBS buffer. Conventional culture and PCR methods were used for identification of bacterial agents. Results: The bacterial cultures in 8.6% of samples were positive by conventional culture, with A. otitidis, M. catarrhalis and S. pneumoniae present in 1.4%, 2.9% and 4.3% of samples, respectively. No H. influenzae was isolated. By the PCR method, A. otitidis was the most frequently isolated bacterium, found in 25.7% of samples, followed by S. pneumoniae, M. catarrhalis and H. influenzae, which were identified in 20%, 12% and 20% of samples, respectively. Overall, 55 out of 70 samples were positive by both the PCR and culture method. Conclusions: It can be concluded that A. otitidis was the major causative agent of MEE in children with OME. Therefore clinicians should be aware that bacterial infection plays an important role in the progression of acute otitis media to OME in children of our region.
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Affiliation(s)
- Ahmad Farajzadah Sheikh
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Nader Saki
- Hearing and Speech Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Mitra Roointan
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Reza Ranjbar
- Molecular Biology Research Center, Baqiyatallah University of Medical Sciences, Tehran, IR Iran
| | - Mohammad Jaafar Yadyad
- Infectious and Tropical Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Abbas Kaydani
- Department of Virology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
| | - Sajad Aslani
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
- Corresponding author: Sajad Aslani, Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran. Tel: +98-6133330074, Fax: +98-6133332036, E-mail:
| | - Mansoor Babaei
- Health Management Research Center, Baqiyatallah University of Medical Sciences, Tehran, IR Iran
| | - Hamed Goodarzi
- Department of Microbiology, School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran
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Concurrent assay for four bacterial species including alloiococcus otitidis in middle ear, nasopharynx and tonsils of children with otitis media with effusion: a preliminary report. Clin Exp Otorhinolaryngol 2012; 5:81-5. [PMID: 22737288 PMCID: PMC3380117 DOI: 10.3342/ceo.2012.5.2.81] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2011] [Revised: 12/21/2011] [Accepted: 12/29/2011] [Indexed: 12/22/2022] Open
Abstract
Objectives To detect the prevalences of Alloiococcus otitidis, as well as Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis in children with chronic otitis media with effusion (OME) and to simultaneously investigate the colonization of these bacteria in the nasopharynx and palatine tonsils of these patients. Methods The study included 34 pediatric patients with OME, and 15 controls without OME. In the study group, A. otitidis, H. influenzae, S. pneumoniae, and M. catarrhalis were investigated in the samples obtained from middle ear effusions (MEE), nasopharyngeal swabs (NPS) and tonsillar swabs (TS), using multiplex polymerase chain reaction (PCR) and conventional culture methods. Only the samples obtained from NPS and TS were studied with the same techniques in the control group. Results A. otitidis was isolated only in MEE and only with multiplex PCR method. A. otitidis, S. pneumoniae, M. catarrhalis, H. influenzae were identified in 35%, 8.8%, 8.8%, and 2.9%, respectively, in 34 MEE. A. otitidis was not isolated in NPS or TS of the study and the control groups. Conclusion The prevalence of A.otitidis is high in children with OME and A.otitidis doesn't colonize in the nasopharynx or tonsil.
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Pulmonary Collectins in Diagnosis and Prevention of Lung Diseases. ANIMAL LECTINS: FORM, FUNCTION AND CLINICAL APPLICATIONS 2012. [PMCID: PMC7121960 DOI: 10.1007/978-3-7091-1065-2_43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Pulmonary surfactant is a complex mixture of lipids and proteins, and is synthesized and secreted by alveolar type II epithelial cells and bronchiolar Clara cells. It acts to keep alveoli from collapsing during the expiratory phase of the respiratory cycle. After its secretion, lung surfactant forms a lattice structure on the alveolar surface, known as tubular myelin. Surfactant proteins (SP)-A, B, C and D make up to 10% of the total surfactant. SP-B and SPC are relatively small hydrophobic proteins, and are involved in the reduction of surface-tension at the air-liquid interface. SP-A and SP-D, on the other hand, are large oligomeric, hydrophilic proteins that belong to the collagenous Ca2+-dependent C-type lectin family (known as “Collectins”), and play an important role in host defense and in the recycling and transport of lung surfactant (Awasthi 2010) (Fig. 43.1). In particular, there is increasing evidence that surfactant-associated proteins A and -D (SP-A and SP-D, respectively) contribute to the host defense against inhaled microorganisms (see 10.1007/978-3-7091-1065_24 and 10.1007/978-3-7091-1065_25). Based on their ability to recognize pathogens and to regulate the host defense, SP-A and SP-D have been recently categorized as “Secretory Pathogen Recognition Receptors”. While SP-A and SP-D were first identified in the lung; the expression of these proteins has also been observed at other mucosal surfaces, such as lacrimal glands, gastrointestinal mucosa, genitourinary epithelium and periodontal surfaces. SP-A is the most prominent among four proteins in the pulmonary surfactant-system. The expression of SP-A is complexly regulated on the transcriptional and the chromosomal level. SP-A is a major player in the pulmonary cytokine-network and moreover has been described to act in the pulmonary host defense. This chapter gives an overview on the understanding of role of SP-A and SP-D in for human pulmonary disorders and points out the importance for pathology-orientated research to further elucidate the role of these molecules in adult lung diseases. As an outlook, it will become an issue of pulmonary pathology which might provide promising perspectives for applications in research, diagnosis and therapy (Awasthi 2010).
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11
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Hartshorn KL, White MR, Smith K, Sorensen G, Kuroki Y, Holmskov U, Head J, Crouch EC. Increasing antiviral activity of surfactant protein d trimers by introducing residues from bovine serum collectins: dissociation of mannan-binding and antiviral activity. Scand J Immunol 2010; 72:22-30. [PMID: 20591072 DOI: 10.1111/j.1365-3083.2010.02409.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Collectins contribute to host defence through interactions with glycoconjugates on pathogen surfaces. We have prepared recombinant trimeric neck and carbohydrate recognition domains (NCRD) of collectins, and we now show that the NCRD of bovine conglutinin and CL-46 (like that of CL-43) have greater intrinsic antiviral activity for influenza A virus (IAV) than the human SP-D NCRD (hSP-D-NCRD). The three serum collectins differ from SP-D by having insertions adjacent to amino acid 325 and substitution of hydrophobic residues for arginine 343. We previously showed that a three amino acid (RAK) insertion, as found in CL-43, increases antiviral activity and mannan-binding activity of the hSP-D-NCRD, while the substitution of valine at 343, as in conglutinin, more strongly increased these activities. Mannan-binding activity of collectins has been considered to predict for ability to bind to high mannose glycans on viruses or other pathogens. We now show, however, that combined mutants containing the RAK insertion and R343V or R343I substitutions have greatly increased mannan-binding ability, but lower IAV binding or inhibiting activity than mutants containing R343V or R343I substitutions only. These findings indicate differences in the recognition of glycan structures of mannan and IAV by the NCRD and emphasize the importance of the flanking sequences in determining the differing interactions of human SP-D and bovine serum collectins with mannose-rich glycoconjugates on IAV and other pathogens. Of interest, we show conservation of some monoclonal antibody-binding epitopes between bovine collectin NCRD and hSP-D, suggesting shared structural motifs.
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Affiliation(s)
- K L Hartshorn
- Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
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12
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Güvenç MG, Midilli K, Inci E, Kuşkucu M, Tahamiler R, Ozergil E, Ergin S, Ada M, Altaş K. Lack of Chlamydophila pneumoniae and predominance of Alloiococcus otitidis in middle ear fluids of children with otitis media with effusion. Auris Nasus Larynx 2009; 37:269-73. [PMID: 19879704 DOI: 10.1016/j.anl.2009.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2008] [Revised: 08/19/2009] [Accepted: 09/08/2009] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To investigate the presence of Chlamydophila pneumoniae and other bacterial pathogens in middle ear effusion samples obtained from children with otitis media with effusion (OME). MATERIALS AND METHODS Twenty-eight children (mean age 7.03; standard deviation 2.18) with OME unresponsive to medical therapy were included in the study. All of the children underwent ventilation tube insertion under general anesthesia. Eighteen patients were bilaterally affected whereas 10 children had unilateral disease. The middle ear fluids (46 samples in total) were collected during ventilation tube insertion, and were evaluated subsequently for the presence of C. pneumoniae and other bacterial pathogens using polymerase chain reaction (PCR). RESULTS Although all samples were negative for C. pneumoniae, bacterial DNA was detected in 21 of 46 samples. Overall 40% of the patients (4/10) with unilateral involvement, and 61% of the patients (11/18) with bilateral involvement were positive for bacterial DNA. In 6 patients with bilateral OME bilateral samples were positive, whereas 5 patients with bilateral OME showed only unilateral positivity. According to the results of DNA sequencing analysis, all of the positive samples harbored only one bacterial species. In 12 of 46 samples Alloiococcus otitidis DNA (26%), in 7 Haemophilus influenzae DNA (15%), in one Streptococcus pneumoniae DNA (2%) and in one Moraxella catarrhalis DNA (2%) were present. CONCLUSIONS Our findings support that C. pneumoniae does not seem to have a role in OME in children whereas A. otitidis was found to be more frequent than the other common pathogens. Further studies are required to elucidate the exact pathogenetic role of these microorganisms in OME.
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Affiliation(s)
- Melih Güven Güvenç
- Istanbul Bilim University, Medical Faculty, Department of Otorhinolaryngology, Turkey.
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Harimaya A, Koizumi JI, Fujii N, Himi T. Interleukin-8 induction via NF-kappaB, p38 mitogen-activated protein kinase and extracellular signal-regulated kinase 1/2 pathways in human peripheral blood mononuclear cells by Alloiococcus otitidis. Int J Pediatr Otorhinolaryngol 2007; 71:1465-70. [PMID: 17629956 DOI: 10.1016/j.ijporl.2007.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 05/30/2007] [Accepted: 06/02/2007] [Indexed: 01/08/2023]
Abstract
Alloiococcus otitidis is a newly recognized species of gram-positive bacteria frequently associated with otitis media. Although immunostimulating activity of this organism has been investigated, little is known about the signaling pathways of chemokine/cytokine induction by this organism. We investigated the role of NF-kappaB and mitogen-activated protein (MAP) kinases in chemokine interleukin-8 (IL-8) production by human peripheral blood mononuclear cells (PBMCs) after stimulation with A. otitidis. The organism could induce in vitro IL-8 production in human PBMCs. I kappa B alpha, NF-kappaB, p38 MAP kinase, p44/42 MAP kinase (ERK1/2) became phosphorylated in PBMCs after stimulation with A. otitidis. And, inhibitors of NF-kappaB (caffeic acid phenylethyl ester), p38 (SB 203580), or ERK1/2 (PD 98059) significantly reduced IL-8 induction by the organism. These results were similar to findings in IL-8 induction by Streptococcus pneumoniae, another gram-positive major middle ear pathogen. Our preliminary study suggests that multiple pathways including NF-kappaB, p38, and ERK1/2 were simultaneously activated, and were associated with IL-8 induction by A. otitidis in human PBMCs.
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Affiliation(s)
- Atsushi Harimaya
- Department of Otolaryngology, Sapporo Medical University School of Medicine, S-1, W-16, Chuo-ku, Sapporo, Hokkaido 060-8543, Japan.
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Sorensen GL, Husby S, Holmskov U. Surfactant protein A and surfactant protein D variation in pulmonary disease. Immunobiology 2007; 212:381-416. [PMID: 17544823 DOI: 10.1016/j.imbio.2007.01.003] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2006] [Accepted: 01/02/2007] [Indexed: 12/17/2022]
Abstract
Surfactant proteins A (SP-A) and D (SP-D) have been implicated in pulmonary innate immunity. The proteins are host defense lectins, belonging to the collectin family which also includes mannan-binding lectin (MBL). SP-A and SP-D are pattern-recognition molecules with the lectin domains binding preferentially to sugars on a broad spectrum of pathogen surfaces and thereby facilitating immune functions including viral neutralization, clearance of bacteria, fungi and apoptotic and necrotic cells, modulation of allergic reactions, and resolution of inflammation. SP-A and SP-D can interact with receptor molecules present on immune cells leading to enhanced microbial clearance and modulation of inflammation. SP-A and SP-D also modulate the functions of cells of the adaptive immune system including dendritic cells and T cells. Studies on SP-A and SP-D polymorphisms and protein levels in bronchoalveolar lavage and blood have indicated associations with a multitude of pulmonary inflammatory diseases. In addition, accumulating evidence in mouse models of infection and inflammation indicates that recombinant forms of the surfactant proteins are biologically active in vivo and may have therapeutic potential in controlling pulmonary inflammatory disease. The presence of the surfactant collectins, especially SP-D, in non-pulmonary tissues, such as the gastrointestinal tract and genital organs, suggest additional actions located to other mucosal surfaces. The aim of this review is to summarize studies on genetic polymorphisms, structural variants, and serum levels of human SP-A and SP-D and their associations with human pulmonary disease.
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Harimaya A, Takada R, Himi T, Yokota SI, Fujii N. Evidence of local antibody response against Alloiococcus otitidis in the middle ear cavity of children with otitis media. ACTA ACUST UNITED AC 2006; 49:41-5. [PMID: 17094788 DOI: 10.1111/j.1574-695x.2006.00166.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alloiococcus otitidis is a recently discovered bacterium frequently associated with otitis media. However, no study is available as to whether A. otitidis has a pathogenic role and induces local immune response in the middle ear as a true pathogen. Whole bacterial sonicate of A. otitidis was separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and transferred to a nitrocellulose membrane. Then, Western blot analysis was performed with supernatant of the middle ear effusions from children with A. otitidis-positive otitis media. SDS-PAGE of the bacterial sonicate showed several protein bands, designated A1-A11. Western blot analysis revealed the presence of IgG, secretory IgA, IgG2, and IgM against A. otitidis in the middle ear effusions. Absorption of the specimens with sonicates of other major middle ear pathogens did not alter the reactivity of antibodies against the alloiococcal antigens. The results suggest that specific local immune response against A. otitidis is induced during middle ear infection of the organism as a true pathogen. A5, A6 or A11 is expected to be a main antigenic determinant. This is the first report to show evidence of local antibody response against A. otitidis and to disclose antigenic components of A. otitidis.
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Affiliation(s)
- Atsushi Harimaya
- Department of Otolaryngology, Sapporo Medical University School of Medicine, Sapporo, Japan.
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