Biomedical subjects

A Ebenfelt

Publications and source records attributed to A Ebenfelt.

8 recordsLinked to original sources

PubMed2001

Neutrophil migration in tonsils.

Recent studies have indicated the existence of an active cellular defence in the secretion on the tonsillar surface. This defence seems to consist partly of physiologically active neutrophils and is present in health and during disease. The present study was undertaken to examine the migration of these neutrophils to the secretion on the mucosal surface. Tonsils from 6 patients with acute tonsillitis and 5 patients with snoring problems were removed and sectioned. Sections were stained immunohistochemically against CD15 to visualise neutrophils. Other sections were stained with acridine orange to detect bacteria. Clusters of neutrophils were frequently seen in tonsils both from patients with acute tonsillitis and from snorers. They were observed to be accumulated within the tonsillar epithelial layer. Streaks of neutrophils could be observed running not only from vessels mainly near or within the epithelium to the epithelial surface, but also from vessels far from the epithelium through the extrafollicular areas to the epithelial surface. Bacteria were not present in the epithelium. We consider that the findings indicate an active physiological migration of neutrophils to the tonsillar surface.

Acridine Orange↗

PubMed2000

Absence of bacterial infection in the mucosal secretion in chronic laryngitis.

OBJECTIVES: To examine whether an infectious process is present in the laryngeal secretion in patients with chronic laryngitis. STUDY DESIGN: Mucosal secretion from vocal cords and ventricular folds from 14 patients with chronic laryngitis was examined. Twelve patients with healthy larynxes served as control subjects. METHODS: Secretion from the laryngeal mucosa was sampled with an imprint technique during general anesthetic. The samples were stained and examined by light and fluorescence microscopy. The numbers of leukocytes and bacteria and the extension of phagocytosis were estimated. RESULTS: In the secretion from eight of the patients with chronic laryngitis we could observe huge numbers of bacteria, whereas only few bacteria were seen in the secretion from the control subjects. However, in both groups, only a few neutrophils were observed and phagocytosis was not present, indicating that the bacteria were present as colonizers. CONCLUSIONS: No infectious process is present in the secretion in chronic laryngitis. Further studies concerning the pathogenesis should focus on the pathological processes or conditions of the mucosa.

Bacterial Infections↗

PubMed1998

Acute pharyngotonsillitis is an infection restricted to the crypt and surface secretion.

A commonly accepted hypothesis is that acute pharyngotonsillitis is caused by bacteria which first adhere to the epithelial surface and then invade the tonsillar parenchyma; however, evidence directly supporting this hypothesis is not available. In previous studies on acute pharyngotonsillitis, we found that the secretion in crypts and at the surface was infected in acute pharyngotonsillitis while no bacteria were detected in the parenchyma. Based on these results, we have proposed a new hypothesis stating that the infection is restricted to the crypt and surface secretions in acute pharyngotonsillitis. To evaluate this hypothesis further, in the present study we examined tonsillar tissue and secretion from patients with acute pharyngotonsillitis, recurrent pharyngotonsillitis and healthy tonsils. Surface secretion was studied after sampling by an imprint technique followed by routine histological preparation. Tonsillar tissue was examined by fluorescence microscopy after staining with acridine orange and by transmission electron microscopy. There were high numbers of bacteria and moderate or extensive ongoing phagocytosis in the crypt and surface secretion from patients with acute pharyngotonsillitis. Bacteria, leucocytes and phagocytosis were also present, but to less extent in the secretion from patients with recurrent pharyngotonsillitis and to even less extent in the healthy controls. In none of all the investigated tonsils were bacteria present in the parenchyma. Bacterial adherence to the epithelial surface was only very rarely observed. This study supports the hypothesis that acute pharyngotonsillitis is an infection restricted to the crypt and surface secretion and that bacterial adherence is not of significant importance in the pathogenesis of acute pharyngotonsillitis.

Adenoids↗

PubMed1997

Do the leukocytes in the surface secretion on the adenoid have an immunological function?

To elucidate whether leukocytes in the surface secretion on the adenoid have a potential immunological function, imprint samples of surface secretion were obtained from the adenoid of 11 children and the corresponding mucosal area of 10 adults. May-Grünewald-Giemsa staining was used for evaluation of cell morphology and spatial relations, and immunohistochemical staining for identification of granulocytes, B cells, T cells and macrophages. The children's imprints showed large numbers of leukocytes, with mononuclear cells in the majority. The adults' imprints were characterized by moderate numbers of epithelial cells and few leukocytes. In six out of seven adenoid secretions successfully analysed with all four CD antigens, there was the simultaneous presence of granulocytes, B cells, 1 cells and macrophages. This was the case in one of nine analysable adult secretions. The CD-positive cells were often seen in juxtaposition, in clusters of two to 10 cells, as well as in contact with leukocytes of unknown CD antigenicity and epithelial cells. The simultaneous presence in the secretion of morphologically intact and CD antigen-presenting leukocytes in juxtaposition could indicate a potential immunological function of these cells.

Adenoids↗

PubMed1996

Neutrophils in mucosal secretion are functionally active.

The leucocytes in the secretion on the tonsillar surface have been regarded as inactivated and dying cells with no essential function in the defence of the underlying mucosa. In recent studies, we showed that in acute tonsillitis there are very few, if any, bacteria in the parenchyma, whereas in the secretion on the tonsillar surface there are huge numbers of bacteria and neutrophils, and furthermore, extensive phagocytosis. The present study was performed to elucidate the functional capacity of the neutrophils in the secretion on the tonsillar surface. Secretion samples were taken from the tonsillar surface of healthy volunteers with an imprint technique which allows transfer of secretion from the mucosa to a glass slide with maintained topographic position of the cells. The capacity of the neutrophils to respond to chemotactic stimuli and to phagocytize and further process labelled yeast particles was studied in this in vitro system. The results show that the neutrophils in the secretion have the same properties as in tissue, and also when having arrived in the secretion they can identify and attack new prey.

Adult↗

PubMed1996

Cellular defence in surface secretion in acute pharyngotonsillitis.

As acute pharyngotonsillitis is contagious the offensive organisms are supposed to enter mostly from the outside of the diseased person into the tonsillar secretion and tissues. To elucidate the function and the pathophysiological importance of the cellular defence system in the surface secretion of the tonsils, the cellular kinetics and spatial relations between the cellular elements in the secretion were followed during the course of acute pharyngotonsillitis in 16 patients using a newly invented imprint technique. The most prominent findings in the secretions at the start of the infections, irrespective of positive or negative bacterial culture for beta-haemolytic streptococci, were huge numbers of bacteria, great numbers of granulocytes, many of which showed signs of exhaustion and death, and extensive intracellular and frustrated phagocytosis, features highly consistent with an infectious process. During healing there were rapid and profound changes in cellular content and spatial relations towards those in secretions of healthy volunteers. However, even in the surface secretions of these subjects, bacteria, granulocytes and in some areas phagocytosis were present, albeit to a significantly lesser extent. It is concluded that a cellular defence system is constantly active in the surface secretions of the tonsils. During disease, this system is strongly activated and stressed. Based on our recent and present results it is speculated that acute pharyngotonsillitis is primarily and often only due to the emergence of an overload on the cellular defence system of the surface secretion.

Adult↗

PubMed1995

Imprints from the oropharyngeal mucosa: a novel method for studies of cell-kinetics and spatial relations between leukocytes, epithelial cells and bacteria in the secretion on the surface of the mucosa.

Cell-kinetics and spatial relations between the cellular elements in the secretion on the mucosal surfaces of the oral cavity and the pharynx were studied with a new imprint technique whereby pieces of foam-plastic are pressed against the mucosal surfaces and then immediately against a glass slide. For visualisation of leukocytes, epithelial cells and bacteria, imprints were stained according to May Grünewald-Giemsa and with acridine orange. For visualisation and discrimination between T and B-cells, slides were stained with immunohistochemical technique using anti-CD-3 and anti-CD-19, respectively, as antibodies. Imprints were also prepared for scanning electron microscopy (SEM). The results show that there are large numbers of morphologically intact cells in the secretions and that there are statistically significant differences between the different mucosal areas as regards numbers, types and spatial relations between the cellular elements in the surface secretions. Rather great inter- and intra-individual differences in cellular composition were observed, indicating a dynamic system. This was further documented by observation of a dominance of polymorphonuclear leukocytes on the tonsillar surface, in contrast to the dominance of mononuclear leukocytes in secretion from the mesopharynx. We consider that this new imprint method is reliable and gives representative samples from the surface secretion. The results clearly show the need for further studies concerning the physiological role of the cellular elements in the surface secretion of the oral cavity and mesopharynx.

Bacteria↗

PubMed1994

Bacterial invasion of the tonsillar tissues in acute pharyngotonsillitis and in the adenoid: a preliminary study.

In order to understand the immunological and inflammatory processes in which the tonsils are involved it is necessary to know the spatial relation between bacteria and the tissues. In this study four adenoids and four palatine tonsils obtained at elective surgery and four palatine tonsils obtained during à chaud surgery for quinsy were examined histologically. Acridine orange and fluorescence microscopy were used to identify bacteria in tonsillar tissue. The adenoids were also stained with haematoxillin-eosin. Bacteria were in every case seen on the surfaces and in the crypts of the tonsils and adenoids. In the tissues, however, bacteria were never seen irrespective of whether the tonsils were obtained during an acute infection or not. We conclude that bacterial invasion in tonsillar tissue is neither a prerequisite for a clinically manifest acute bacterial pharyngotonsillitis nor a common feature in tonsils clinically recognized as non-infected.

Acute Disease↗