Single cell analysis of adenoid CD5+ B cells and their protective contributions to nasopharyngeal immunity

Immunoglobulins and Transcription Factors in Otitis Media

The causes of otitis media (OM) involve bacterial and viral infection, anatomo-physiological abnormalities of the Eustachian canal and nasopharynx, allergic rhinitis, group childcare centers, second-hand smoking, obesity, immaturity and defects of the immune system, formula feeding, sex, race, and age. OM is accompanied by complex and diverse interactions among bacteria, viruses, inflammatory cells, immune cells, and epithelial cells. The present study summarizes the antibodies that contribute to immune reactions in all types of otitis media, including acute otitis media, otitis media with effusion, and chronic otitis media with or without cholesteatoma, as well as the transcription factors that induce the production of these antibodies. The types and distribution of B cells; the functions of B cells, especially in otorhinolaryngology; antibody formation in patients with otitis media; and antibodies and related transcription factors are described. B cells have important functions in host defenses, including antigen recognition, antigen presentation, antibody production, and immunomodulation. The phenotypes of B cells in the ear, nose, and throat, especially in patients with otitis media, were shown to be CD5^low, CD23^high, CD43^low, B220^high, sIgM^low, sIgD^high, Mac-1^low, CD80(B7.1)^low, CD86(B7.2)^low, and Syndecam-1^low. Of the five major classes of immunoglobulins produced by B cells, three (IgG, IgA, and IgM) are mainly involved in otitis media. Serum concentrations of IgG, IgA, and IgM are lower in patients with OM with effusion (OME) than in subjects without otitis media. Moreover, IgG, IgA, and IgM concentrations in the middle ear cavity are increased during immune responses in patients with otitis media. B cell leukemia/lymphoma-6 (Bcl-6) and paired box gene 5 (Pax-5) suppress antibody production, whereas B lymphocyte inducer of maturation program 1 (Blimp-1) and X-box binding protein 1 (XBP-1) promote antibody production during immune responses in patients with otitis media.

Short-term effect of adenotonsillectomy on growth and nutritional anthropometric parameters of children with obstructive adenotonsillar enlargement

Background

Obstructive adenotonsillar enlargement is known to cause failure to thrive in children. The effect of adenotonsillectomy is not well documented on the growth of affected children. The study was carried out to investigate the effect of adenotonsillectomy on growth of children with obstructive adenotonsillar enlargement. It was a quasi-experimental study consisting of 62 children (≤ 12 years) with obstructive adenotonsillar enlargement and 62 healthy controls. Variables measured at baseline, sixth week and 13th week post adenotonsillectomy, were weight, height, mid-upper arm circumference, and triceps skinfold thickness. The percent of weight-for-age and height-for-age were, respectively, calculated by dividing the child’s weight and height by the median expected weight and height (i.e., the 50th percentile) based on the child’s chronological age. The obtained weight-for-age and height-for-age values were used to determine the presence of failure to thrive and stunting, respectively.

Results

Majority (70.6%) of the patients with malnutrition were from a low socioeconomic class. At baseline, failure to thrive and stunting were found among 17 (26.4%) cases and 11 (17.7%) controls, but the proportion reduced to six (9.7%) and three (4.8%), respectively, at the 13th week post adenotonsillectomy. There was a steady increase in weight-for-age, height-for-age, mid-upper arm circumference, and triceps skinfold thickness in both cases and controls from baseline to the 13th week. However, there was a significant difference in percentage variation of these variables between the two groups.

Conclusions

Adenotonsillectomy improved the growth of children with obstructive adenotonsillar enlargement and hence recommended in cases with failure to thrive and stunting.

Comparing Oxygen Saturation of Normal Children with that of Children with Adenotonsillar Hypertrophy

To compare the nocturnal oxygen saturation profiles of children with adenotonsillar enlargement with that of normal children. A 1 year comparative study. The study was carried out at the Otorhinolaryngology Ward of the University College Hospital Ibadan. These comprise of 60 children (1-9 years) with clinically confirmed adenotonsillar enlargement admitted for adenotonsillectomy and 60 normal children matched for age and sex. The biodata and common clinical presentations of the study group were acquired with a structured proforma. The severity of nasopharyngeal obstruction was determined by the adenoidal-nasopharyngeal ratio while the degree of tonsillar enlargement was graded by the Brodsky's classification. The nocturnal oxygen saturation of all the participants were recorded with a wrist worn pulse oximeter. Recording was for at least for 4 h. Oxygen saturation <92 % was regarded as desaturation. The oximetric values of the study and control group were compared. The mean nocturnal SPO2 (peripheral saturation of oxygen) profiles of children with adenotonsillar enlargement were as follows: basal = 96.86 %, minimum = 84.99 %; maximum = 99 % and average SPO2 <92 % = 87.74 % while the saturation profiles of the control group were as follows; basal = 97.88 %, minimum = 89.71 %; maximum = 99 %, average SPO2 <92 % = 90.82 %. Normal children have better nocturnal saturation profiles than children with adenotonsillar enlargement.

Evaluation of airway obstruction by adenoid tissue: comparison of measures in the sitting and recumbent

OBJECTIVE

To measure the airway obstruction caused by adenoid hypertrophy in the sitting and recumbent positions in search of hypothesized differences.

METHODS

Forty eight children between the ages of 2 and 12 years who sought the department of otorhinolaryngology spontaneously complaining of snoring and/or nasal obstruction. Children could be either male or female and belong to any social or racial group. Patients underwent nasal videoendoscopy sitting and lying performed by the same investigator. An image of the posterior nasopharynx was obtained from each nasal cavity of each patient for both positions. The free area of the nasopharynx was measured and compared in both positions. Image analysis was performed by two researchers other than that who carried out the examination.

RESULTS

The nasopharynx free area obtained with seated patient is, on average, 53% bigger than the free area obtained with the patient lying down (confidence interval: 95%; p<0.001). Thus, adenoidal obstruction is larger when the examination is performed with the patient lying down.

CONCLUSIONS

Nasal videoendoscopy to evaluate adenoid hypertrophy with the patient lying down makes testing more reliable, better reproducing the patient's position when sleeping. Such accuracy is essential since it influences the decision for surgical intervention in this important and widespread disease in the pediatric population.

[Expression CD27 on T and B lymphocytes in hypertrophied adenoids at children with otitis media with effusion]

INTRODUCTION

Adenoid has particular meaning to develop of immunological response to inflammations in upper respiratory inclusive middle ear. The mining of antigen CD27 on lymphocytes T and B in creation of memory cells is still unclear.

AIM

CD27 on lymphocytes T and B has a crucial role in development of immune response against inflammatory state. Aim of this study was evaluation functions of lymhocytes with expression CD27 in hypertrophied adenoid in children with otitis media with effusion.

MATERIAL AND METHODS

[corrected] We tested 24 children in examine group with hypertrophied adenoid and otitis media with effusion (OME), and 29 children in comparative group only with hypertrophied adenoid (HA). We also divided both groups into two groups, above 5 and over 5 years old. We made the research by flow cytometry method. We used anty-CD19, anty-CD3, anty-CD5 and anty-CD27 monoclonal antibodies to examinations.

RESULTS

We showed the lowest percentage lymphocytes B CD5+ with expression of CD27 in subgroup older children with otitis media with effusion (O.M.E. 22.43 +/- 2.66%) in compartative to younger children in the same group (15.96 +/- 5.31%; p < 0.005) and to older comparative subgroup (H.A. 15.50 +/- 8.03; p < 0.001). Percentages of B CD5 cells with expression of CD27 was statistical lower in examinated group (7.25 +/- 3.81) than in comparative group (H.A. 16.26 +/- 5.82; p < 0.04). In group with hypertrophied adenoid showed higher percentages of CD5-CD27+CD19+ cells both in younger and older supgroup than in equivalent supgroups with O.M.E.

CONCLUSIONS

Iteraction of CD27-CD70 regulates many functions of T and B lymphocytes. It seems that disorders humoral immunologucal answer in hypertrophied adenoids are supported to develop of otitis media with effusion.

Mucin gene expression in hypertrophic adenoids

CONCLUSION

Membrane-bound mucin MUC4 represents the predominant mucin expressed in the adenoid epithelium followed by MUC5AC (gel-forming mucin). This may suggest that membrane-bound mucins could be involved in pathogen binding and immunological stimulation.

OBJECTIVES

The aim of this study was to investigate mucin expression in hypertrophic adenoids.

MATERIALS AND METHODS

Adenoidal samples were obtained from 12 children. The expression of eight mucin genes, MUC1-4, MUC5AC, 5B, 6 and 7 was studied by in situ hybridization utilizing digoxigenin-labelled oligonucleotide probes.

RESULTS

The dominant mucin genes were MUC4, 3 and 5AC, while MUC1, 2, 5B and 7 were sparsely expressed and MUC6 was not expressed. Expression patterns were very different from those in the upper airways. Most samples expressed two membrane-bound mucins (MUC4 and 3) and one secretory mucin (MUC5AC).

Squamous metaplasia and BCL-6 in pediatric adenoid accompanied by otitis media with effusion

PURPOSE

Deterioration of local immunity in the adenoids may make them vulnerable to infection by microorganisms, resulting in otitis media with effusion. To determine the factors associated with this condition, we evaluated adenoid size, mucosal barrier, squamous changes of ciliated epithelium, IgA secretion, and BCL-6 expression in adenoids.

MATERIALS AND METHODS

Seventeen children diagnosed with otitis media with effusion (OME group) and 20 children without any history of OME (control group) were enrolled. Their adenoids were sized by lateral view X-ray and stained with hematoxylin and eosin to detect squamous metaplasia. The adenoids were also stained with cytokeratin to evaluate mucosal barriers, and with anti- IgA antibody and anti- BCL-6 antibody to determine expression of IgA and BCL-6.

RESULTS

The OME group showed greater incidence of squamous metaplasia, fewer ciliated cells, and lower expression of BCL-6 (p < 0.05 each). Deterioration of the mucosal barrier was detected in the OME group (p > 0.05). IgA secretion and adenoid size were the same for the OME and the control groups.

CONCLUSION

These results suggest that increased squamous metaplasia and lower BCL-6 expression in adenoids may be associated with increased susceptibility to OME.

B cells in murine cervical lymph nodes are conventional B-2 cells

We investigated the characteristic features of cervical lymph node B cells to determine whether their behavior differs from that of B cells located elsewhere, because cervical lymph nodes may be exposed to continual antigenic stimulation from the naso- and/or oropharynx. B cells were isolated from cervical lymph nodes, spleen and peritoneal fluid of mice, cultured in medium, and exposed to various stimuli. The expression of various surface molecules characteristic of lymphoid B cells was assayed by flow cytometry, and immunoglobulin secreted into the culture supernatants was evaluated by enzyme-linked immunosorbent assay. B220+ cells were cultured in medium alone or with lipopolysaccharide, and their entrance into S phase in response to stimuli was measured by proliferative assays. Phenotypic characteristics of cervical lymph node B cells included CD5 low, CD23high, CD43low, B7.1low, B7.2low, and Syndecan-1low. Unstimulated lymphoid B cells did not secrete immunoglobulin, but, upon stimulation, secretion of IgM was increased more than secretion of IgA and IgG. B cells actively entered S phase after 48 hr stimulation. These results show that B cells in cervical lymph nodes are conventional B2 cells, like splenic B cells.

Rotavirus-specific CD5+ B cells in young children exhibit a distinct antibody repertoire compared with CD5- B cells

Antiviral antibody responses in infants are limited in quality. One reason for this finding could be that the majority of B cells in infants are CD5+ cells, a subset of B cells that is thought to contain cells expressing polyreactive, low-affinity B cell receptors. We analyzed the rotavirus (RV)-specific antibody heavy chain variable region (VH) repertoire in CD5+ and CD5- B cells of four RV-infected children between 10 and 19 months of age. We found that the RV-specific B cell repertoire in CD5+ cells was VH3 family biased, in contrast to the VH1/VH4 dominance seen in CD5- B cells. The immunodominant RV-specific gene segment in CD5- B cells was VH1-46, which is the dominant segment used in RV-specific peripheral blood B cells from infants and adults. In contrast, the immunodominant gene segment was VH3-23 in RV-specific CD5+ B cells, which is the dominant gene segment in randomly selected B cells. Both RV-specific CD5+ and RV-specific CD5- B cells from all children studied demonstrated very low frequencies of somatic mutations. In conclusion, CD5+ B cells in infants responding to RV use an antibody gene repertoire that differs from the virus-specific repertoire of CD5- B cells, and both CD5+ and CD5- RV-specific B cells exhibit a low frequency of somatic mutations.

Characteristic features of B cells in murine cervical lymph nodes

CONCLUSION

B cells in cervical lymph nodes correspond to typical conventional B cells (B-2).

OBJECTIVE

The special status of cervical lymph nodes in relation to the oropharynx, and the need to maintain the integrity of the oropharnygeal mucosal barrier, suggest the possibility that cervical lymph node B cells located in the oropharynx may behave differently from B cells located elsewhere. In this study we examined the symmetry or lack thereof between cervical lymph node B cells and other B-cell subsets.

MATERIAL AND METHODS

We isolated B cells from murine cervical lymph node tissue and evaluated them in vitro according to several criteria.

RESULTS

We found that cervical lymph node B cells expressed typical B-cell phenotypic markers and proliferated normally in response to mitogenic stimulation. They did not spontaneously secrete immunoglobulin and, in keeping with this, did not express elevated levels of either CD138 (Syndecan-1), a marker for plasma cells, or BLIMP-1, a putative master regulator of B-cell differentiation.