Immunological function of human tonsils, with special reference to E- and EAC-binding lymphocytes

Immunoglobulin subclasses in chronic tonsillitis

The distribution and proportion of immunoglobulin-producing cells in palatine tonsil, including IgG and IgA subclasses, have been examined in chronic tonsillitis using an immunofluorescence method. Results obtained indicate that the percentage ratios of IgG1:IgG2:IgG3:IgG4 were 53.1:35.9:4.7:6.3. Higher percentages of IgG1- and lower percentages of IgG2-producing cells were found among 3 types of tonsillitis. Proportional ratios of IgA1:IgA2 were approximately 80:20, and a slight elevation of IgA2-producing cells was observed in chronic tonsillitis.

Lymphocyte subsets in human adenoids and tonsils. Rosette formation, alpha-naphthyl acetate esterase cytochemistry, monoclonal antibodies and peanut lectin reactivity

The distribution of mononuclear cell subsets has been studied in human adenoids, tonsils and peripheral blood (PB) by evaluating the presence of surface immunoglobulins, E-rosette formation, receptors for IgG Fc and for complement, alpha-naphthyl acetate esterase (ANAE) cytochemistry, reactivity with peanut lectin (PNA) and with monoclonal antibodies (McAb) (OK panel). Adenoids and tonsils, compared to PB, contain (1) fewer macrophages and T cells but more B cells; (2) higher proportions of ANAE negative, complement receptors and Ia-like antigens bearing T lymphocytes; (3) higher percentages of cells reacting with the McAbs OKT9 and OKT10 ("immature" lymphoid cells). In both adenoids and tonsils, clusters, formed by a central heavily ANAE stained interdigitating cell surrounded by lymphocytes with a sickle-shaped ANAE reaction, were found. Analogous clusters have been previously described in mice and human thymus. Two major hypotheses could be put forward: (1) adenoids and tonsils contain "immature" lymphoid cells undergoing education process, or (2) the above organs contain lymphocytes activated by a constant exposure to bacterial antigens or mitogens.

T cell subsets in the tonsil in relation to age analyzed with monoclonal antibodies (anti-leu antibodies) and fluorescence activated cell sorter (FACS)

The ratio of the cells reacting to anti-leu 1, 3a and 4 antibodies is as low as that of T cells in the tonsil to those in the peripheral blood. The number of the tonsillar cells reacting to anti-leu 2a and 7 antibodies is still smaller. Fluorescence intensity of tonsillar lymphocytes reacting to leu (1, 2a, 3a, and 4) antibodies is lower than that of peripheral blood lymphocytes. Adult tonsillar lymphocytes have higher ratios of the cells reacting to anti-leu 1, 2a, 3a, 4 and 7 antibodies than child tonsillar lymphocytes and fluorescence intensity of the cells reacting to these anti-leu antibodies tended to be higher in adult tonsillar lymphocytes. These findings suggest less cytotoxic/suppressor T and NK/K function cells in the tonsil than in the peripheral blood. From these, it is conceivable that the tonsillar lymphocyte constitution becomes closer to that of peripheral blood as the child grows up. Further, immature T cells are present in the tonsil, though in a small number. This tendency is stronger in children than in adults.

T and B lymphocyte rosettes in tonsils of atopic and non-atopic children

This investigation was carried out to determine the immunological function of the human tonsils, especially the role of lymphocytes of atopic and non-atopic children. An E- and EAC-rosette forming technique is introduced, with semiquantitative evaluation of T and B lymphocytes in the peripheral blood of 56 normal subjects, 28 atopic and 5 non-atopic children of both sexes and different ages. The percentage of T and B lymphocytes in removed palatine tonsils in 28 atopic and 5 non-atopic children was calculated. The percentage of rosette-forming cells in E and EAC suspensions appeared to be independent of age and sex. The percentage of T lymphocytes in peripheral blood was significantly higher than in the palatine tonsils, whereas the percentage of B lymphocytes was significantly higher in the tonsils of atopic and non-atopic children than in the peripheral blood. The mean percentage of B lymphocytes in the tonsils of atopic children was significantly higher than in non-atopic children. The percentage of B lymphocytes was found to be significantly higher in hypertrophic than in small tonsils. Also, in the tonsils with adhesions there was a statistically significantly higher percentage of EAC rosettes than in the tonsils free of adhesions. The percentage of T lymphocytes was statistically significantly higher in the small tonsils.

Particularity of local immunity in the nasopharynx. Parallel study of surface receptors and cell-mediated immune responses in cells derived from palatine or pharyngeal tonsils and blood

Immunological functions of the pharyngeal tonsil, palatine tonsils and blood leucocytes of children undergoing tonsillectomy were evaluated by determining T or B lymphocytes, the response to mitogens, and the cell-mediated immunological responses to tuberculin. In all the test systems used similar results were obtained with cells derived from either the palatine or pharyngeal tonsils. The mean percentage of T lymphocytes was significantly higher in the peripheral blood than in tonsils, but the reverse was true of B lymphocytes. The reaction to PHA was lower in tonsillar cell culture than in blood cell culture, but tonsillar cells reacted better to Con A than blood cells. In lymphocyte transformation tests tonsillar cells reacted to specific antigen (tuberculin) and this reaction was significantly higher than that of the parallelly tested blood lymphocytes. Further, in about 50% of the children tested, tuberculin caused migration inhibition of the mixture containing tonsillar cells and guinea pig peritoneal cells. Surprisingly, nearly identical results were obtained if migration inhibition test was performed with tonsillar cells alone. Consequently, poorly migrating tonsillar cells are nevertheless usable for direct migration inhibition testing.

Studies on the identification of B lymphocytes using protein A. Lymphocytes of human palatine tonsil

The prinicpal methods presently being applied to distinction of the subpopulations of lymphocytes consist in the E-rosette method for T cells and the EAC-rosette method for B cells. However, it has been learned that other cells have the ability to form rosettes. B cells are employed in various experiments due to the explicitly verifiable immunoglobulin on the surface of lymphocytes. However, as the fluorescent antibody method adopted as the method for verification has a number of difficulties, we tried to determine B cells by utilizing protein A, by combining protein A with SRBC (sheep red blood cells) and forming rosettes, both in human peripheral blood and in human intratonsillar lymphocytes. As a result, it was noted that lymphocytes indicating positivity existed at a level of 15-20% in human blood and 40-45% in the tonsil.

Immunoglobulin levels of tonsillar cells

Immunoglobulin G, A and M contents of homogenized tonsillar lymphocytes were measured. Higher Ig values were found in adults than in children. Inflammatory processes increased the immunoglobulin levels of tonsillar lymphocytes. The changes in tonsillar IgG and IgA levels suggest the importance of local immunoglobulin production in the defence mechanism of tonsils. Two isolated IgA deficiencies were detected among the 85 patients.

Characterization of clinical tonsil stages by their T-cell count. Immunopathological description of tonsils after a peritonsillar abscess

The T-cell counts in five different clinical tonsil stages are compared. No particularities were observed, with the exception of the condition after a peritonsillar abscess. The differences existing between the individual groups are discussed as age-dependent. A considerable increase in T-cells is found in the abscess tonsil compared with other tonsils and the T-cell count in blood. Its pathomechanism is discussed.

Clinical immunological study of T lymphocytes and EA rosette forming cells in tonsils

Tonsillar E and EA rosette forming lymphocyte subpopulations were studied in 120 tonsillectomized patients. T cell ratios was usually lower in the tonsils than in the blood. EA binding cells were studied with indicator systems of human or rabbit antibody sensitized red cells, respectively. Poorly sensitized human RBCs (EArabbit) bind much better to tonsillar cells than to blood lymphocytes and so this system proved to be specially suitable to study tonsillar EA binding cells. Increase in E and EA rabbit rosette forming cell frequencies were found with the age of patients. Decrease in percentage of T cells and EA rabbit rosette binding cells were found with high frequency of acut tonsillitis and with clinical sysmptoms of chronic local inflammation. The variation of these lymphocyte subpopulations with the local tonsillar inflammatory processes suggest a considerable clinical immunological role of local T cells and of this portion of Fc receptor postive lymphocytes.

Cell fractionation and cytological analysis of human lymphatic cells from tonsil and blood

No differences could be detected in the discontinuous density gradient when comparing the distribution pattern of tonsillar cells and peripheral lymphocytes. When the Kiel nomenclature is applied, the presence of centrocytes, centroblasts, lymphocytes and plasma cells in the tonsil is shown by a cytological analysis. The biological importance of these results is discussed from the point of cellular proliferation and tonsillar function.

Studies on the capacity of human tonsillar lymphocyte subpopulations to produce interferon

Tonsillar lymphocytes produced classical interferon (Type I) in response to NDV infection and produced immune interferon (Type II) in response to PHA, PPD or histo-incompatible antigens. Lymphocytes having higher specific gravity and having a greater proliferative response to mitogens or antigens produced more interferon than lymphocytes having lower specific gravity. There was no difference between heavy and light small tonsillar lymphocytes in regard to their sensitivity to the protective effects of interferon. As for the interferon produced in association with a cellular immune response, the peak of interferon production tended to appear earlier than the peak of 3H-TdR incorporation. It is suggested that tonsillar lymphocytes play an important role in human host defense against virus infections.

Studies on difference in cellular immune-response between the human tonsil and blood lymphocytes

Tonsillar and blood lymphocytes in a viable state were separated from tuberculin-sensitive tonsillectomized patients. The difference in the response to various cellular immunological stimulation between both lymphocyte groups was studied. Tonsillar lymphocytes without adherent cells could not respond well to PPD, while blood lymphocytes responded far better than tonsillar lymphocytes did to PPD when adherent cells were absent. PHA and PWM stimulated tonsillar and blood lymphocytes irrespective of the presence of adherent cells. However, in case of PWM stimulation, 3H-TdR incorporation was more remarkable in tonsillar lymphocytes than in blood lymphocytes. Furthermore, the lymphocytes which react to homologous cells also existed in the tonsils as in blood. These results suggest that there might be lymphocyte-subpopulations showing a difference of functional roles or of maturing-process between tonsil and blood lymphocytes.

Immunological function of human tonsil. Surface topology of human tonsil lymphocytes using the scanning electron microscope (SEM)

The surface topology of the lymphocytes in human tonsils was performed by means of the scanning electron microscope (SEM). It was revealed that human tonsils consist of both 40.7% villous and 26.6% smooth surface lymphocytes. In general, the percentage results agree with those of E and EAC binding lymphocytes of human tonsils, as previously reported. Our serial experiments using immunological techniques proved the existence of two lymphocytes (T and B cell) having immunological roles.