Role of persistent infection in the control and severity of asthma: focus on Chlamydia pneumoniae

Hertzen, Leena C. von

doi:10.1183/09031936.02.00254402

Cited by 89 publications

(52 citation statements)

References 102 publications

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“…Matrixins, a family of proteases, of which MMP9 is the predominant form in pulmonary tissue, can digest components of the ECM, while TIMP1, a major specific inhibitor of MMP9, has fibrogenic properties and promotes the multiplication of fibroblasts and myofibroblasts (Gueders et al, 2006). Increased levels of MMP9 have been detected in the bronchoalveolar lavage fluid, sputum and sera (Bossé et al, 1999;Mautino et al, 1997;von Hertzen, 2002) of asthmatic patients and there is a significant correlation between MMP9 level, decreased forced expiratory volume in 1 s (FEV1) and irreversible airway obstruction (Boulay et al, 2004;Mattos et al, 2002).…”

Section: Discussionmentioning

confidence: 99%

Chlamydophila pneumoniae inhibits corticosteroid-induced suppression of metalloproteinase-9 and tissue inhibitor metalloproteinase-1 secretion by human peripheral blood mononuclear cells

Park

Lee

Kwon

et al. 2012

Journal of Medical Microbiology

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Chlamydophila pneumoniae infection has been suggested to be associated with severe asthma characterized by persistent airway limitation, which may be related to airway remodelling. We investigated whether C. pneumoniae infection affected the secretion of metalloproteinase-9 (MMP9) and tissue inhibitor metalloproteinase-1 (TIMP1), and altered the responsiveness of inflammatory cells to corticosteroids. Human peripheral blood mononuclear cells (PBMCs) were cultured in vitro in the presence or absence of C. pneumoniae. Secretion of both MMP9 and TIMP1 was strongly suppressed by dexamethasone treatment in uninfected cells. MMP9 secretion was also significantly inhibited by dexamethasone in C. pneumoniae-infected cells, but TIMP1 secretion was not; hence the MMP9 to TIMP1 ratio decreased. Interestingly, expression of human glucocorticoid receptor b, which is believed to confer resistance to corticosteroids, was enhanced by dexamethasone treatment in C. pneumoniae-infected PBMCs. We conclude that C. pneumoniae infection may promote airway remodelling by decreasing the ratio of MMP9 to TIMP1 secreted by inflammatory cells, and by altering cellular responsiveness to corticosteroids.

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Section: Discussionmentioning

confidence: 99%

Chlamydophila pneumoniae inhibits corticosteroid-induced suppression of metalloproteinase-9 and tissue inhibitor metalloproteinase-1 secretion by human peripheral blood mononuclear cells

Park

Lee

Kwon

et al. 2012

Journal of Medical Microbiology

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“…Rhinoviruses are responsible for approximately 60% of the respiratory viral infections, whilst influenza, parainfluenza, respiratory syncytial virus, and adenovirus are responsible for the rest. Mycoplasma pneumoniae and Chlamydia pneumoniae cause chronic inflammation of the lower respiratory tract [45][46][47]. The mechanisms of viral-and bacterial-induced asthma onset or exacerbations are still under investigation [48][49][50].…”

Section: Discussionmentioning

confidence: 99%

Household Conditions, Eczema Symptoms and Rhinitis Symptoms: Relationship with Wheeze and Severe Wheeze in Children Living in the Polokwane Area, South Africa

Wichmann

Wolvaardt

Maritz

et al. 2008

Matern Child Health J

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Background This is the fifth study that applied the International Study of Asthma and Allergies in Childhood (ISAAC) methodology in the Southern African Development Community (SADC region). However, it is the first ISAAC study that focused on 6-to 7-year-old children living in South Africa and that also investigated the association between potential risk factors and asthma symptoms. Objective To assess the 12-month prevalence of wheeze and severe wheeze along with their potential risk factors. Setting Within a 60-km radius from the Polokwane city centre, Limpopo Province. Methods The survey was conducted during August 2004 and February 2005. Parents/guardians of 6-to 7-year-old children completed the questionnaires in English, Afrikaans or North-Sotho. However, the statistical analyses were restricted to the North-Sotho group (n = 2,437). Results The 12-month prevalence rates of wheeze and severe wheeze were 11.2% and 5.7%, respectively. The 12-month prevalence rates of eczema symptoms and rhinoconjunctivitis symptoms were 8.0% and 7.3%, respectively. Living in a rural area significantly decreased the likelihood of wheeze by 31%. Exposure to environmental tobacco smoke at home and the presence of eczema symptoms and rhinoconjunctivitis symptoms increased the likelihood of wheeze by 77%, 104% and 226%, respectively. Only the presence of rhinoconjunctivitis symptoms increased the likelihood of severe wheeze by 107%. Conclusion Wheeze appears to be an emerging public health problem in the Polokwane area. Hopefully, detailed analytical intervention studies will further explicate these results in the near future.

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“…The eosinophils have an important role in the pathophysiology of nonasthmatic eosinophilic bronchitis [Brightling et al 2003, 2002, 2000a, 2000b, Brightling and Pavord, 2000Gibson et al 1998]. In nonasthmatic eosinophilic bronchitis there is eosinophilia in the sputum, BAL and bronchial biopsies.…”

Section: Nonasthmatic Eosinophilic Bronchitismentioning

confidence: 99%

“…However, it is unclear whether these associations predominantly result from (1) infection fixing Th2 responses and facilitating the subsequent development of inflammation and asthma, or (2) immune responses that lead to inflammation and asthma also predisposing to atypical bacterial infection. Hence, it has been proposed that the timing of the infection relative to the exposure, the age of first infection, and/or the underlying immune phenotype of the individual that predispose to C. pneumoniae-induced allergy and asthma rather than the nature of the infection per se [Von Hertzen, 2002]. Similarly, it has recently been reported that patients with severe asthma sensitised to A. fumigatus, that do not conform to the conventional diagnostic criteria of allergic bronchopulmonary aspergillosis not only have radiological radiological abnormalities on high-resolution computed tomography such as bronchiectasis, bronchial wall thickening and bronchial dilatation, but also air flow limitation due to air trapping [Menzies et al 2011].…”

Section: Confirmation Of Tramentioning

confidence: 99%

Unusual asthma syndromes and their management

Morjaria

Kastelik

2011

Therapeutic Advances in Chronic Disease

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Asthma usually presents with symptoms of wheeze, dyspnoea and cough. However, clinicians should be aware of atypical presentation of this disorder when cough is the main or only symptom in conditions such as cough-variant asthma, nonasthmatic eosinophilic bronchitis and atopic cough. Early diagnosis and treatment of these conditions with inhaled corticosteroids improves symptoms in the majority of patients. Up to 10% of patients with asthma remain poorly controlled in spite of optimal standard therapy. These patients have been encompassed under the term 'treatment-refractory asthma' (TRA), have the greatest morbidity and are responsible for more than 50% of healthcare costs. In this review we discuss investigations, management and pathophysiology of the various phenotypes of atypical presentations of asthma as well as novel biological agents licensed and those that have been reported in clinical trials in terms of their efficacy and safety in TRA.

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Role of persistent infection in the control and severity of asthma: focus on Chlamydia pneumoniae

Cited by 89 publications

References 102 publications

Chlamydophila pneumoniae inhibits corticosteroid-induced suppression of metalloproteinase-9 and tissue inhibitor metalloproteinase-1 secretion by human peripheral blood mononuclear cells

Chlamydophila pneumoniae inhibits corticosteroid-induced suppression of metalloproteinase-9 and tissue inhibitor metalloproteinase-1 secretion by human peripheral blood mononuclear cells

Household Conditions, Eczema Symptoms and Rhinitis Symptoms: Relationship with Wheeze and Severe Wheeze in Children Living in the Polokwane Area, South Africa

Unusual asthma syndromes and their management

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