Th Cell Population, Eosinophilia And Related Transcription Factors In Nasal Polyps

Th Cell Population, Eosinophilia and Related Transcription Factors in Nasal PolypsPARTⅠTh1 and Th2 Cell Population in Nasal Polyps, A flow cytometry AssayBackground The nasal polyposis (NP) remains a common clinical entity. Classification of nasal polyp is a controversial topic. Its etiology and pathogenesis is still not entirely known. There exist two theories concerning the pathogenesis of nasal polyps, the staphylococcus aureus superantigen theory and the fungul allergy theory. The NPs is the ultimate manifestation of chronic inflammation. Bacterial infection, viral infection, fungal infection, allergy, and environmental pollution have all been suggested as possible initial triggers that may upregulate inflammation of the lateral wall of the nose to develop NPs. In most cases, the lamina propria of NPs demonstrates large numbers of eosinophils and lymphocytes. These infiltrated cells may play a part in pathogenesis of the polyp.Demonstration of the existence and functions of T help cells (Th1 and Th2 cells) has been an enormous impact on basic and applied immunology. Th1 and Th2 cells have a crucial role in balancing the immune response. Th1 cells produce interferon-gamma (IFN-γ), promoting cell-mediated immunity and control of intracellular pathogens. It related with the immune response induced by infectious agents. In contrast, Th2 cells produce interleukin-4 (IL-4), which promotes allergic responses. It related with the immune response induced by allergy.Previously, the study about T cell in chronic rhinosinusitis (CRS) and nasal polyps (NP) was limited to the T cell subpopulation and cytokines, but lacking deep study on Th cell. There was no reports concerning the Th cell in NPs with and without allergy. To analyze the immunological pattern of NP in patients with and without allergy, and evaluate the role of infectious agents and allergy in the etiology and pathogeneses of NPs, the percentages of CD4+ cells expressing intracellular IFN-γand IL-4 (Th1 and Th2 cells) were measured by flow cytometry. Methods 16 cases of NPs without allergy and 16 cases of NPs with allergy were involved in this study. Based on medical history of allergy and skin prick test, the NPs with allergy or the NPs without allergy were differentiated. The fresh NP samples were prepared into single cell suspension for flow cytometric analysis. Th1 cells were defined as CD4+ lymphocytes with intracellular IFN-γbut without intracellular IL-4. Th2 cells were defined as CD4+ lymphocytes with intracellular IL-4 but without intracellular IFN-γ.Results Nasal polyp possesses both Th1 and Th2 cells, but Th1 cells presented the majority in all the NPs. There was no significant difference in the mean percentages of IFN-γ-producing Th1 cells between the NPs without allergy group (Mean＝46.28, SD＝4.95) and the NPs with allergy group (Mean＝38.25, SD＝9.16; P＞0.05); The mean percentages of IL-4-producing Th2 cells in the NPs with allergy group(Mean＝7.34, SD＝2.54) were significantly higher than that in the NPs without allergy group(Mean＝0.63, SD＝0.31, P＜0.01 ).Conclusions Th1 cells were predominant in NPs; The NPs with allergy possesses more Th2 cells than the NPs without allergy did; The NPs without allergy and the NPs with allergy have some difference in immunological pattern.PARTⅡEosinophilia and Its correlation with Th2 Cells in Nasal PolypsBackground During the last two decades, there has been an increased awareness regarding the role of the eosinophil in several physiologic and pathologic processes. Eosinophil progenitors are released from the blood marrow into the circulation and are chemically attracted to the site of action by chemotactic factors. Development and maturation of eosinophils can also occur in situ in peripheral sites of inflammation containing pre-existing increased tissue eosinophils. The eosinophil is involved in physiologic and pathologic processes, such as asthma, parasitic diseases, granulomatous disorders, fibrosis, malignant tumors and several sino-nasal diseases. In AR, eosinophils are mainly involved in the late-phase reaction after infiltration from the peripheral blood into the tissue. Cytokines secreted by Th-2 cells account for recruiting and activating the eosinophils in the nose. Among them, IL-4 is considered to be pivotal, since it promotes IgE synthesis, up-regulates adhesion molecules selective for eosinophil recruitment, and causes increased mucus production.The role of the eosinophil in the pathogenesis of CRS and NP has been particularly emphasized in the past few years. The lamina propria of NP demonstrates large numbers of eosinophils. Eosinophilic granulocytes are known to carry a variety of cytotoxic proteins in their granula, which can be released by degranulation. These proteins include the eosinophilic cationic protein(ECP), major basic protein(MBP), eosinophilic peroxidase(EPO) and eosinophil-derived neurotoxin(EDN). The cytotoxicity of the eosinophils may be a crucial element of an immunological reaction against allergen and fungi, which are present in the nasal mucus. Histopathologic studies of the CRS and NP demonstrate eosinophilic infiltration was a characteristic of NP, but there was less study concerning the eosinophilic infiltration difference in NPs with and without allergy, and there was no reports concerning the relation of the eosinophilic infiltration with the Th2 cells population. In these experiment, to define the eosinophilia in NPs with and without allergy and explore the eosinophilic infiltration mechanism in NPs, eosinophil counting were carried out on the H&E staining sections of all the NP samples. The correlation between the mean percentages of the Th2 cells and the eosinophilia were analyzed.Methods Eosinophil counting were carried out on the H&E staining sections of all the NP samples. The mean percentages of IL-4-producing Th2 cells were measured by flow cytometric analysis. Using SPSS for Windows Ver.11.5 Statistics Package, the average eosinophils number of the two patient group were compared by Independent Samples T-test. The correlation between the mean percentages of the Th2 cells and average eosinophils number of all cases were analysed by Bivariate Correlaions.Results Eosinophilia was significantly upregulated in the NPs with allergy group (Mean＝54.5, SD＝15.76) compared with it did in the NPs without allergy group(Mean＝14.38, SD＝5.6, P＜0.01 ). Additionally, significant positive relationships were found between the mean percentages of IL-4-producing Th2 cells and the average eosinophil numbers in all the polyps (r＝0.80, P＜0.01).Conclusions Eosinophilia was significantly upregulated in the NPs with allergy. The cytotoxicity of the eosinophils may be a crucial element of an immunological reaction against allergen and fungi, which are present in the nasal mucus. Eosinophilia may induced by Th2 cells in the NPs.PARTⅢTh Cell Differentiation Related Transcription Factors in Nasal PolypsBackground The differentiation of naive CD4+ T cells into Thl or Th2 effector cells is a critical process during immune responses. Th1 cells produce interferon-gamma (IFN-γ), promoting cell-mediated immunity and control of intracellular pathogens. It related with the immune response induced by infectious agents. In contrast, Th2 cells produce interleukin-4 (IL-4), which promotes allergic responses. It related with the immune response induced by allergy. T-bet and GATA3 are two important transcription factor in regulating Th cell differentiation. T-bet promotes Th1 cell differentiation, and GATA3 promotes Th2 cell differentiation. T-bet and GATA3 have antagonistic effect on each other. There was no reports concerning the Th cell differentiation related transcription factor in NPs with and without allergy. To analyze the immunological pattern of NPs in patients with and without allergy, and evaluate the role of infectious agents and allergy in the etiology and pathogeneses of NPs, the mRNA expression of T-bet and GATA-3 were analyzed by real-time quantitative PCR in NPs with allergy and the NPs without allergy.Methods The samples were devided into three groups, which include 16 cases of NPs with allergy, 16 cases of NPs without allergy and 10 cases of inferior turbinate mucosa samples. Liquid nitrogen stored samples were analyzed by real-time quantitative PCR for mRNA expression of T-bet and GATA-3. Total RNA was extracted from tissue using TRIzol Reagent, Using reverse transcriptase, cDNA was synthesized. Real-time PCR analyses were performed in BIO RAD Icycler 5 and analyzed by Icycler version3.1.7050 software.Results The three groups have significant difference in GATA3 and T-bet mRNA expression (F＝83.26, P＜0.01; F＝17.6, P＜0.01). Multiple Comparison in ANOVA analysis demonstrated that the expression of T-bet and GATA3 mRNA was significantly higher in the two NPs groups than that in the inferior turbinate mucosa (P＜0.01, or P＜0.05). The NPs with allergy had significantly higher expression of GATA3 mRNA than that in the NPs without allergy (P＜0.01). The NPs with allergy and the NPs without allergy have no significant difference in T-bet mRNA expression (p＞0.05).Conclusions NPs expressed higher level of T-bet and GATA3 mRNA than that in the inferior turbinate mucosa. NPs with allergy expressed higher level of GATA3 mRNA than the NPs without allergy did. NPs without allergy and NPs with allergy have some difference in immune response and pathogenesis.