Distribution of lymphoid cells in tonsillar compartments in relation to infection and age. A quantitative study using image analysis

Determinants of physiological uptake of 18F-fluorodeoxyglucose in palatine tonsils

To determine the extent of physiological variation of uptake of F-flurodeoxyglucose (FDG) within palatine tonsils. To define normal limits for side-to-side variation and characterize factors affecting tonsillar uptake of FDG.Over a period of 16 weeks 299 adult patients at low risk for head and neck pathology, attending our center for FDG positron emission tomography/computed tomography (PET/CT) scans were identified. The maximum standardized uptake value (SUVmax) was recorded for each palatine tonsil. For each patient age, gender, smoking status, scan indication and prior tonsillectomy status as well as weather conditions were noted.There was a wide variation in palatine tonsil FDG uptake with SUVmax values between 1.3 and 11.4 recorded. There was a strong left to right correlation for tonsillar FDG uptake within each patient (P < .01). The right palatine tonsil showed increased FDG uptake (4.63) compared to the left (4.47) (P < .01). In multivariate analysis, gender, scan indication, and prevailing weather had no significant impact of tonsillar FDG uptake. Lower tonsillar uptake was seen in patients with a prior history of tonsillectomy (4.13) than those without this history (4.64) (P < .01). Decreasing tonsillar FDG uptake was seen with advancing age (P < .01). Significantly lower uptake was seen in current smokers (SUVmax 4.2) than nonsmokers (SUV 4.9) (P = .03).Uptake of FDG in palatine tonsils is variable but shows a strong side-to-side correlation. We suggest the left/ right SUVmax ratio as a guide to normality with a first to 99th percentiles of (0.70-1.36) for use in patients not suspected to have tonsillar pathology.

Age-related differences in human palatine tonsillar B cell subsets and immunoglobulin isotypes

The tonsils provide defense of the upper aerodigestive tract against pathogens. Although long known to undergo functional changes with age, the precise changes occurring within tonsillar B cell populations remain undefined. In the present study, we investigated age-related changes in palatine tonsillar B cell subsets and immunoglobulin (Ig) isotypes. Palatine tonsils were obtained from forty-two tonsillectomy patients without tonsillitis who were divided into three groups: young children (4-9 years), adolescents (10-19 years), and adults (20-60 years). Tonsillar B cells were then analyzed by flow cytometry. Using expression of CD38 and IgD to define B cell subsets, we found that the frequency of germinal center (GC) B cells in the tonsils was significantly higher, and the frequency of memory B cells lower, in young children as compared to adolescents and adults. Within the GC B cell subsets, adults had a higher frequency of IgA(+) cells and a lower frequency of IgM(+) cells as compared to individuals in the younger age groups. Moreover, young children had a higher frequency of IgG(+) cells in the GC B cell subsets than did individuals in the older age groups. We also observed an abundance of IgM(+) cells among memory B cells and plasmablasts in young children and IgA(+) cells in adults. In summary, the proportion of GC B cells in palatine tonsillar B cells decreases with age, while the proportion of memory B cells increases with age. In addition, Ig isotypes in tonsils preferentially switch from IgM to IgA as individuals age.

Tonsillitis index: an objective tool for quantifying the indications for tonsillectomy for recurrent acute tonsillitis

This report is a preliminary exploration of the concept of a "Tonsillectomy Index" (TI) as an objective tool for quantifying the indications for tonsillectomy for recurrent acute tonsillitis (AT). The TI is derived by multiplying the number of episodes of AT by the number of years during which the episodes of AT occurred. Our objective in this study was to investigate whether there is a relationship between the natural history of AT, the immunological functions of tonsils and our proposed TI. For the natural history of AT, we medically followed 11 children with a history of AT for 5 years. When TI was equal to or greater than 8 (TI> or =8), the children suffered a significantly greater number of episodes of AT. For the immunological portion of our study, we enrolled 36 children and 46 adults undergoing tonsillectomy for either AT (study group) or tonsillar hypertrophy (control group, CG). We analyzed the co-stimulatory signals, CD80 and CD86 on tonsillar B-lymphocytes. The expression rates of CD80 and CD86 in the AT group with TI> or =8 were significantly decreased compared to those with TI was less than 8 (TI<8), as well as with those in control (tonsillar hypertrophy) group. Our preliminary findings suggest that when the TI> or =8, the tonsils have deteriorated immunologically and spontaneous resolution of recurrent AT is less likely to occur, hence tonsillectomy is appropriate. TI may be a useful tool for surgical decision making.

Implication of immunological abnormalities after adenotonsillotomy

The adenoids and tonsils are thought to be essential parts of the system protecting organism against pathogens invading the upper respiratory tracts. Human adenoids and tonsils are known to be immunologically reactive lymphoid organs, which manifest specific antibodies and B and T cells activity in response to variety of antigens carrying out the functions of humoral and cellular immunity. The purpose of the study was to observe the changes in systemic immunity in children with hypertrophy of adenoids and tonsils treated in Department of Laryngology, Children's Hospital in Warsaw in period 1994-1999. The study comprised 80 patients (33 girls and 47 boys, aged from 3 to 14 years, mean age 6.8 years) with diagnosed hypertrophy of adenoids and tonsils. The diagnosis of hypertrophy of adenoids and tonsils was based on characteristic history and laryngological examination. All patients were scheduled for adenotonsillotomy. The control group comprised 40 people (14 girls and 26 boys, aged from 3 to 15 years, mean age 7.6 years) without history of the recurrent upper tract infections. In all patients we carried out following examinations: serum levels of immunoglobulins A, G, M (humoral immunity); percentage of T lymphocytes (CD3); percentage of T helper (CD4) and T cytotoxic (CD8) lymphocytes (cellular immunity) and delayed cutaneous hypersensitivity-Multitest CMI (cell mediated immunity). Our study demonstrate that in children with hypertrophy of adenoids and tonsils exist changes in the immunological parameters. The observed changes appear not only locally but also generally. In the early period after adenotonsillotomy there was statistically significant decrease of the values of humoral and cellular immunity parameters. However, 6 months after operation we observed normalization of examined immunological parameters. We think that the examinations of parameters of immunological system (humoral and cellular) are necessary before planned adenotonsillotomy.

Lymphocyte subpopulations in hypertrophied adenoid in children

Adenoid hypertophy is a common feature of childhood. It is currently accepted that it is caused by the antigen-stimulated increased activity of lymphocyte B (D. Bani, O. Gallo, O. Fini-Storchi, Intraepithelial lymphocyte subpopulations and dendritic accessory cells in normal and hypertrophic adenoids, Laryngoscope 10 (1994) 869-873). The adenoid decreases its size with age but the accompanying function alterations are not fully understood (L. Zawadzka-Glos, M. Chmielik, M. Wasik, Cell mediated response in hypertrophied tonsils in children, Nowa Pediatr. 4 (1997) 12-13). The understanding of the adenoid structure that undergoes some changes during the growth period is essential for evaluation of indications for adnoidectomy and assessment of its potential results. The aim of this study was to evaluate lymphocyte subpopulations in adenoid according to age. The analysed material was adenoids removed on the grounds of hypertrophy, which caused obstructive symptoms and/or otitis media with effusion onset. In the present study, we did not find any statistically significant differences among lymphocytes B, Th, and Ts subpopulations, respectively, in the adenoids of any of the age groups. We have found a statistically significant CD3(+) HLA-DR(+) cell percentage decrease in the group of children from 5 to 10 and above 10 years of age, respectively. We have also found a statistically significant increase in the percentage of NK (CD3(-) CD16(+) 56(+)) lymphocytes in relation to age. On the grounds of the current study, it may be stated that some changes in lymphocyte subpopulations in the adenoid take place with age.

Age-dependent altered proportions in subpopulations of tonsillar lymphocytes

Age-related changes in functional subsets of lymphocytes may influence the potential to build up immune responses. In particular, the capacity of tonsillar lymphocytes to counter infections may be altered during ageing. In order to address this question we investigated the proportional distribution of several subsets of tonsillar T and B cells with regard to ageing. Tonsils were derived from 119 patients between 2 and 65 years of age. Lymphocyte subsets were monitored by three-colour fluorescence of relevant CD markers in flow cytometry. As a general tendency the percentage of CD3+ T cells steadily increased whereas that of CD19+ B cells decreased at the same time. No significant differences were observed between lymphocytes of patients with and without inflammatory history of the tonsils. The percentage of CD8+ T cells declined whereas that of CD4+ T cells increased during the same time span. CD45RA+ T cells increased during the first two decades of life and gradually decreased thereafter. In contrast, CD45RO+ T cells showed an opposite trend. No differences were seen in the population of CD3-/CD56+ natural killer (NK) cells. The mature B cell marker CD40 showed no significant changes during ageing. However, CD38+ B cells, representing B cells of late maturation stages, dramatically declined up to the age of 65. In a similar manner the CD5+ subpopulation of B cells decreased during ageing. Substantial changes in major tonsillar T and B cell populations as shown in this study may have an impact on the ageing process of the immune system.

T-cell subsets in adenoids and peripheral blood related to age, otitis media with effusion and allergy

Adenoids and peripheral blood samples from 29 children (20-120 months of age) undergoing adenoidectomy for long-standing otitis media with effusion (OME) (n=16) or obstructive adenoid hyperplasia (n=13) were investigated by flow cytometry for their T-lymphocyte profile. Eleven of the enrolled children were allergic to inhalant and/or food allergens. For the whole group, the percentage of helper T cells belonging to the memory phenotype (CD4+/CD45RO+ cells) was significantly higher in adenoids than in blood (p<0.0001), while the same cell category increased with age in peripheral blood (p<0.01). A highly significant negative regression (p<0.001) was found between age and the percentage ratio of CD4+ cells that were CD45RO+ in adenoids and blood. Allergic children had a higher CD4+/CD8+ ratio for cells expressing CD45RO+ (p<0.05) in adenoids. The results of this study indicate that adenoids participate in the development of an immunological memory. Our findings support a relationship between allergy and memory cells in adenoids.

Differences in cellular infiltrates in the adenoid of allergic children compared with age- and gender-matched controls

BACKGROUND

Allergic sensitization of the airways occurs in the mucosa of the shock organ, or in the lymphatic stations draining these structures. The lymphatic structure closest to the nasal mucosa is the adenoid.

OBJECTIVES

The objective of this study was to find evidence for our hypothesis that allergic sensitization can occur in the adenoid. Of special interest, in this context are cell types involved in antigen-allergen presentation (e.g. Langerhans cells) and effector cells of allergic disease.

METHODS

In this study cellular infiltrates in adenoids of 16 allergic patients and 16 age- and gender-matched controls were evaluated. The number of cells positive for CD1a, CD4, CD8, CD-68, chymase, tryptase, IgE, MBP and cells positive for interleukin (IL)-4 were determined using immunohistochemical staining techniques. The epithelium, follicles and the interfollicular spaces were evaluated separately.

RESULTS

When comparing the two groups a significant increase in cells positive for CD1a was found in interfollicular spaces of the allergic group (P = 0.008). CD1a+ cells in the follicular space and eosinophils in the interfollicular space showed a trend to be more numerous in the allergic group (P = 0.02 and P = 0.05, respectively). The other cell types investigated did not show significant differences between the groups.

CONCLUSIONS

The results of this study show for the first time that cells involved in allergic sensitization and allergic disease differ in the adenoid of allergic children compared with controls. These findings support our hypothesis that allergic sensitization takes place in the adenoid. Furthermore, this study confirms that CD1a+ (Langerhans) cells are involved in allergic disease.

Immune responses against Streptococcus pyogenes in human palatine tonsils

We investigated cellular immunity against Streptococcus pyogenes in human tonsils by measuring antigen-specific immunoglobulin-secreting cells and the production of cytokines from CD4+ T cells in response to M proteins. The incidence of S pyogenes in tonsils was significantly higher in patients with recurrent tonsillitis (RT) than in patients with tonsillar hypertrophy (TH). M protein-specific immunoglobulin A (IgA) and immunoglobulin G spot-forming cells were increased in patients with RT compared with patients with TH. In RT the number of M protein-specific IgA spot-forming cells was significantly greater in the S pyogenes-negative subjects than in the S pyogenes-positive subjects. Proliferation of CD4+ T cells and production of interferon-gamma (IFN-gamma) and interleukins -2, -4, -5, and -6 (IL-2, IL-4, IL-5, and IL-6) from those T cells were observed in response to M protein. The concentrations of IFN-gamma and IL-4 were higher in RT than in TH. These findings suggest that S pyogenes is associated with the pathogenesis of RT and that immune responses against M protein may play an important role in preventing the colonization of this bacteria in tonsils.

The production of immunoregulatory cytokines is localized to the extrafollicular area of human tonsils

The localization and production at the single cell level of 19 different human cytokines, IL-1 alpha, IL-1 beta, IL-1ra, IL-2, IL-3, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, TNF alpha, TNF beta, IFN gamma, GM-CSF, G-CSF, and TGF beta 1-3, were studied in cryopreserved tonsillar tissue using immunohistochemical staining. The cytokine producing cells, with the exception of IL-1 expressing cells, had a characteristic morphology due to the accumulation of cytokine onto the Golgi organelle. The production of each cytokine was localized to specific compartments in tonsillar tissue sections from children with tonsillar hypertrophy or recurrent tonsillitis in the resting state. Immunoregulatory cytokines such as IL-2, IL-3, IL-4, G-CSF, GM-CSF and TGF beta were produced in the extrafollicular area and entrapped on the cell membranes as well as in pudels in the extracellular matrix surrounding the producer cells. The dominating cytokines both in tissues from recurrent tonsillitis and tonsillar hypertrophy were GM-CSF, G-CSF, and TGF beta 1-3 which were synthezised predominantly in the reticular crypt site. IL-1 alpha, beta and IL-1ra, on the other hand, were localized to the surface and crypt epithelium and to scattered regions in the extrafollicular area. IL-2, IL-6, IFN gamma and IL-10 were found much more often in sections obtained from recurrent tonsillitis tissue compared with those from tonsillar hypertrophy. Reversely, an excessive production of IL-4 was noted in tonsillar hypertrophy compared with that in recurrent tonsillitis. Thus, concomitant production of multiple cytokines was evident with similarities but also differences in cytokine pattern between the two groups studied. The data suggest that T-cell mediated B-cell activation and differentiation take place in the extrafollicular area. Children with recurrent tonsillitis had a higher amount of B-cells and monocytes compared with children with tonsillar hypertrophy. However, the number of CD3, CD4, CD8 or cytoplasmic Ig-positive cells did not differ between the two groups.

Spontaneous immunoglobulin production by adenoidal and tonsillar lymphocytes in relation to age and otitis media with effusion

Spontaneous immunoglobulin (Ig) production by autologous adenoidal and tonsillar lymphocytes cultured without any mitogen was measured by an enzyme-linked immunosorbent assay (ELISA) in 18 children with or without otitis media with effusion (OME). Both IgG and IgA levels synthesized by adenoidal or tonsillar lymphocytes significantly increased with age. The average concentrations of IgG and IgA produced by adenoidal lymphocytes from children with OME were significantly lower than those from children without OME. Adenoidal lymphocytes produced IgG and IgM at significantly lower levels than autologous tonsillar lymphocytes did in children with OME. In contrast, no significant difference between adenoidal and tonsillar lymphocytes was seen on Ig production for any isotypes in children without OME. These results may indicate immunological impairment of the adenoids associated with OME.

Interaction and immunological effect of very late antigen-4, 5, and fibronectin in tonsillar lymphocytes and their relation to age

We examined the expressions of alpha-subunits of very late antigen (VLA)-4 (alpha4) and VLA-5 (alpha5) on tonsillar lymphocytes and the interaction between these integrin receptors and their ligand, fibronectin (FN). Immunohistological and flow cytometric analyses showed that alpha4 and alpha5 were expressed in the lymphoid follicle and were positive on about 10% each of T cells and on 55% and 35% of B cells. When tonsillar B cells were separated by a discontinuous Percoll gradient, the number of alpha4- and 5-positive cells decreased as the cell density went down, while the number of activated cells went up. After in vitro activation of tonsillar B cells by Staphylococcus aureus Cowan I strain (SAC), the expression of alpha5 and the adhesiveness to FN decreased. The increased proliferation of B cells was observed when tonsillar B cells were cultured with immobilized FN. The expressions of alpha-subunits of VLA-4 and VLA-5 on tonsillar T and B lymphocytes increased with age. These results suggest that: i) B cell activation may cause decreased expressions of VLA-4 and -5, which gives a costimulatory effect on B cell activation itself again in cooperation with FN, ii) Increased expressions of VLA-4 and -5 on tonsillar lymphocytes with age may be related to regional immune response of the palatine tonsils.

The lymphoepithelial organization of the tonsil: an immunohistochemical study in chronic recurrent tonsillitis

Interactions between leukocytes and crypt epithelium were extensively investigated in 12 cases of chronic recurrent tonsillitis, using immunohistochemistry and cytofluorimetric analysis of cell suspensions. Intraepithelial leukocytes are a mixed cell population composed of 50 per cent CD20-positive B lymphocytes, 40 per cent T lymphocytes with a 2.7 CD4/CD8 ratio, and 10 per cent CD68-positive macrophages. About 4 per cent of intraepithelial leukocytes are proliferating cells, as indicated by Ki-67 staining. Leukocyte infiltration is associated with expression on epithelial cells of the adhesion molecules ICAM-1 and VCAM-1. Crypt epithelium is supported by a basement membrane showing frequent interruptions and connected with the reticular stroma of the lymphoid tissue, which was stained for fibronectin, tenascin, collagen, and laminin. Extracellular matrix (ECM) distribution was correlated with integrin expression on B and T lymphocytes. It was found that the ECM was arranged differently in the follicles and in the extrafollicular area and that B and T lymphocytes exhibited different patterns of integrin expression.

Flow cytometric quantification of lymphocyte subpopulations and immunoglobulin-containing cells in adenoid tissue in relation to secretory otitis media and age

This study was designed to identify differences in the immunological reactions in adenoid tissue between children suffering from chronic secretory otitis media (SOM) and control children without ear disease. Cell populations were identified using monoclonal antibodies and flow cytofluorometry to facilitate quantitative comparisons. A modification of the FOG method was developed to quantify lymphocytes with intracellular IgG and IgA. Immunological screening was done in the first part of the study. No significant differences were found between the groups regarding cells positive for CD3, CD4, CD8, CD20 or CD25. A significantly higher number of PCA-1 positive cells (presumably plasma cells) were found in the SOM group. The second part of the study concentrated specifically on cells containing IgG or IgA. No statistically significant differences in number of positive cells were found between the groups. When we related the percentage of positive cells to age, a statistically significant decrease with age for IgA-positive cells was found in the SOM group but not in the control group. This result supports the hypothesis that SOM is associated with an immunological reaction that influences immunoglobulin production in adenoid tissue.

In situ analysis of the immune microenvironment of the adenoid in children with and without secretory otitis media

Using monoclonal antibodies and immunohistochemistry, we compared adenoid tissue from 35 children with or without secretory otitis media. Numerous cells infiltrating the reticular crypt epithelium expressed HLA-DR, as did < 10% of the epithelial cells. Of the antigen-presenting cells, CD1a+ dendritic cells showed intraindividual and interindividual variations; CD68+ macrophages and CD22+ B cells were uniformly distributed. The relative frequencies of CD4+ and CD8+ cells were 6.6 +/- 2.0 versus 2.3 +/- 1.2 (p < .001) in the reticular crypt epithelium and 18 +/- 4.5 versus 1.5 +/- 0.9 (p < .001) in the germinal centers. The IL-2 receptor was expressed on < 0.1% of CD3+ T cells. Over 90% of intraepithelial CD3+ T cells were of the CD45RO+ memory phenotype. The proliferation marker Ki67 was almost exclusively found in the germinal centers. That the analyzed parameters showed a similar pattern in both clinical groups suggests that the presence of secretory otitis media may not correlate to specific alterations in the immune microenvironment of the adenoid.

The prognostic value of Ki-67 antigen in non-Hodgkin lymphoma of Waldeyer ring and the nasal cavity

BACKGROUND

A monoclonal antibody, Ki-67, recognizes an antigen expressed in all phases of the cell cycle, except G0, and can be used as a simple histologic marker of cell proliferation. To assess the prognostic value of the growth fraction in non-Hodgkin lymphoma of Waldeyer ring (W-NHL) and the nasal cavity (N-NHL), the authors applied Ki-67 immunostaining combined with image analysis on such lymphomas.

METHODS

The authors studied 29 patients (18 with W-NHL and 11 with N-NHL), applying Ki-67 to frozen sections. The number of Ki-67-positive cells in a unit area (0.044 mm2), as an indicator of proliferative activity, and the mean area per Ki-67-positive cell (microns2), as an indicator of DNA content, were measured by the image processing system.

RESULTS

High-grade lymphomas showed a significantly larger number of Ki-67-positive cells than intermediate-grade lymphomas (102.5 +/- 21.6 in high-grade and 46.8 +/- 8.92 in intermediate-grade lymphomas, P = 0.03), even when analyzed separately by immunophenotypes. A large mean area per Ki-67-positive cell was associated significantly with a T-cell phenotype (36.3 +/- 7.69 microns2 in T-cell lymphomas and 19.4 +/- 2.33 microns2 in B-cell lymphomas, P = 0.034) and an unfavorable clinical outcome. High proliferative activity, defined as nuclear Ki-67 expression in 2000 or more B-cell lymphoma cells and 1000 or more T-cell lymphoma cells in a 1-mm2 area, was found to be a strong predictor of poor survival among these patients (P = 0.048 and P = 0.009, respectively).

CONCLUSIONS

Ki-67 immunostaining, combined with image analysis, is a novel method for determining a tumor proliferative index that provides useful clinical data regarding head and neck lymphomas.