Specialization of Tonsils as Analyzers of the Human Immune System

Karchev, Todor

doi:10.3109/00016488809124999

Cited by 15 publications

(4 citation statements)

References 7 publications

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“…When antigens enter the oropharyngeal cavity the reticulated crypt epithelium is the first tonsillar compartment that is challenged immunologically (Karchev 1988;Brandtzaeg and Halstensen 1992;Yamanaka et al 1996). The membranous (M) cells not only transport the antigens across the epithelial barrier, but also form a specific intraepithelial micro-compartment that brings together high concentrations of foreign antigens, lymphocytes, and antigen-presenting cells such as macrophages and dendritic cells ).…”

Section: First Step In the Immune Responsementioning

confidence: 99%

Morphology and immunology of the human palatine tonsil

Nave

Gebert

Pabst

2001

Anatomy and Embryology

184

158

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At the surface of the respiratory and digestive organs the organism first comes into contact nasally and orally with various foreign agents and substances in the air and in food. The palatine tonsils are located at the centre of this strategic region. Immunological processes, both humoral and cellular, are initiated in the different specialised compartments of the palatine tonsils, such as the crypt epithelium, lymphoid follicles and extrafollicular region. Each compartment has a typical composition of lymphocytes and dendritic cell subsets. This review summarises current data on the anatomy, histology, and pathology of the human palatine tonsils, describes their fundamental immunological functions, and provides insight into the various interactions involved in the initiation of immune responses. The palatine tonsil is the only easily accessible human lymphoid organ and is often taken as an example for lymphoid organs. Although affections of the palatine tonsils constitutes an essential part in the clinical routine, it is still controversial whether tonsillectomy is of general benefit. This is of increasing importance since it has been discovered in the last few years that the palatine tonsils are reservoir and replication sites of HIV.

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Section: First Step In the Immune Responsementioning

confidence: 99%

Morphology and immunology of the human palatine tonsil

Nave

Gebert

Pabst

2001

Anatomy and Embryology

184

158

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“…The tonsils are located at a crucial position for immunological detection of airborne and ingested antigens. The reticulated crypt epithelium is the first compartment that is challenged immunologically (Karchev, ), acting as a barrier but also as a site of active interaction between pathogens and the innate and adaptive branches of the immune system. Alterations in HBD expression have been associated with several inflammatory diseases, including Crohn's disease, atopic dermatitis, psoriasis and chronic rhinosinusitis with nasal polyps (Chen et al ., ; Hata & Gallo, ; Ramanathan et al ., ; Jansen et al ., ; Zilbauer et al ., ).…”

Section: Introductionmentioning

confidence: 99%

Reduced tonsillar expression of human β-defensin 1, 2 and 3 in allergic rhinitis

Bogefors

Kvarnhammar

Höckerfelt

et al. 2012

FEMS Immunol Med Microbiol

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Airway infections are known to cause exacerbations of allergy and asthma. Tonsils constitute a primary site for microbial recognition and triggering of the immune system in the airways. Human β-defensins (HBDs) are antimicrobial peptides with an important role in this defense. Our aim was to investigate HBD1-3 in tonsillar tissue and their potential role in allergic rhinitis (AR). Tonsils, obtained from patients with AR and non-allergic controls, and isolated tonsillar CD4(+), CD8(+) and CD19(+) lymphocytes were analyzed for HBD1-3 expression using real-time RT-PCR and/or immunohistochemistry. Tonsillar tissue, mixed tonsillar lymphocytes and airway epithelial cells (AECs) were cultured with or without IL-4, IL-5, IL-13 or histamine followed by measurements of HBD1-3 release using ELISA. HBD1-3 were present in tonsillar tissue, including epithelial, CD4(+), CD8(+) and CD19(+) cells. The expression was reduced in allergic compared to healthy tonsils. Stimulation of AECs with IL-4, IL-5 and histamine down-regulated the HBD release, whereas no effects were seen in cultured tonsils or lymphocytes. This study demonstrates presence of HBD1-3 in tonsils and that the levels are reduced in patients with AR. Together with the down-regulation of HBDs in epithelial cells in the presence of allergic mediators suggest that AR patients have an impaired antimicrobial defense that might make them more susceptible to respiratory tract infections.

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“…Many studies have shown that these secondary immune organs play an important role in nasopharyngeal immunity. The lymphoreticular tissues of tonsils and adenoids are directly exposed to the outside environment [3][4][5]. The importance of interleukins (IL-2, IL-4, IL-10 and IL-12), interferon-g (IFNg), and cachectin-a (TNFa) in controlling and/or enhancing the local immune response in nasopharyngeal lymphoid tissue has been well documented [1,[6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%