合并HBV感染的晚期血吸虫病患者外周血Th1/Th2类细胞因子的表达及临床意义

目的 研究合并HBV感染的晚期血吸虫病患者外周血Th1/Th2类细胞因子的表达及临床意义.方法 选择合并HBV感染的晚期血吸虫病患者、乙型肝炎后肝硬化患者、单纯晚期血吸虫病患者各30例,分别设为A、B和C组,分别采用日立7600全自动生化分析仪检测肝功能,lightcycle基因荧光定量分析仪检测HBV DNA,流式细胞检测技术检测外周血Th1和Th2类细胞因子,并进行比较.结果 A组丙氨酸转氨酶水平、天冬氨酸氨基转移酶水平、总胆红素水平高于B组、C组,差异均有统计学意义,(A组与B组比较t=4.725、3.292、3.012;A组与C组比较t=4.568、3.126、3.217,P均＜0.05);A组HBV DNA水平低于B组,差异有统计学意义(t =3.916,P＜0.05).A组外周血IFN-γ、TFN-α表达水平较B组、C组增加,A组与C组之间差异有统计学意义(t =3.652、3.413,P均＜0.05).A组外周血IL-4、IL-13表达水平高于B组,低于C组,但与B组和C组之间结果比较差异均无统计学意义(A组与B组比较t=0.721、0.452、A组与C组比较t=0.625、0.632,P均＞0.05).结论 合并HBV感染的晚期血吸虫病患者,在疾病的发生发展中Th1类细胞因子可能起了重要作用.     

Mitogen-induced cytokine responses of maternal peripheral blood lymphocytes indicate a differential Th-type bias in normal pregnancy and pregnancy failure

PROBLEM: Profiles of Th1- and Th2-type cytokines were studied in women with a history of successful pregnancy and in women with a history of unexplained recurrent spontaneous abortions (RSA) with the objective of elucidating Th1- and Th2-type bias in normal pregnancy and pregnancy failure. METHOD OF STUDY: Peripheral blood mononuclear cells (PBMCs) from 54 women with a history of normal pregnancy and 23 women with a history of unexplained RSA, obtained at delivery or on the day of abortion, respectively, were stimulated with phytohemagglutinin (PHA), followed by the estimation of four Th2 cytokines and four Th1 cytokines. RESULTS: Significantly greater levels of Th2 cytokines were produced by the normal group than by the RSA group. On the other hand, significantly higher levels of Th1 cytokines were produced by the RSA group than by the normal pregnancy group. CONCLUSIONS: These data support the concept that unexplained recurrent spontaneous abortion is associated with an increase in Th1-type reactivity, while Th2 dominance is a feature of successful pregnancy.     

Fas-FasL in Hashimoto's Thyroiditis

Hashimoto's thyroiditis is a common chronic autoimmune disease characterized by the loss of thyroid follicular cells (thyrocytes) that are gradually replaced by lymphocytic infiltration and diffuse fibrosis. These morphological findings suggested that autoreactive T-cell clones were responsible for thyrocyte destruction and hypothyroidism through effector–target cytotoxic recognition. Later, autonomous interaction between thyrocyte Fas and FasL has been proposed as a major mechanism of thyrocyte depletion in Hashimoto's thyroiditis. Here, we analyze the possible role of Fas and FasL in the pathogenesis of Hashimoto's thyroiditis. We suggest that the Fas–FasL system dictates the outcome of the autoimmune response by acting on both immune and target cells.     

Kinetics and functional implications of Th1 and Th2 cytokine production following activation of peripheral blood mononuclear cells in primary culture

The importance of cytokine production in some disease processes is now widely recognized. To investigate temporal relationships between cytokines, we stimulated peripheral blood mononuclear cells (PBMC) in vitro using the T cell mitogen phytohemagglutinin (PHA) and various antigens chosen to induce predominantly Th1 (streptokinase: streptodornase or purified protein derivative) or Th2 (Dermatophagoides pteronyssinus, bee or wasp venom: allergens in sensitive subjects) responses. Cytokine production was measured by sensitive bioassays or enzyme-linked immunosorbent assays. Of the 30 subjects studied, 10 were normal and 20 individuals were allergic to either D. pteronyssinus (n = 10) or bee venom (n = 10) (examined before specific allergen immunotherapy). We examined the temporal profiles of a panel of cytokines produced in prmary culture. In PHA-driven cultures, cytokines were found to be sequentially produced in the order interleukin (IL)-2, IL-4, IL-5, IL-3, interferon (IFN)-γ, IL-10, IL-6, IL-12 and tumor necrosis factor (TNF)-α. The response to allergen in allergic patients was predominantly Th2 in nature, with the production of IL-4, IL-5, IL-6 and IL-10, but little or no IFN-γ. IL-2, IL-3, TNF-α and IL-12 were also produced in low amounts. The response of both atopic and normal subjects to recall bacterial antigens was predominantly Th1, with high levels of IFN-γ, IL-2 and TNF-α. The relevance of the order, amount and speed of production, characteristic kinetics (production, consumption, homeostatic regulation) and the cell source of the cytokines are discussed.     

乙型肝炎患者外周血细胞中Th1/Th2型细胞因子的表达及其临床意义

目的 :探讨Th1 Th2型细胞因子在HBV感染的临床多种表现形式中的表达特征及其临床意义。方法 :采用四色法流式细胞术检测乙型肝炎患者和正常人外周血细胞中CD3+CD8+、CD3+CD8-细胞内的IFN γ和IL 4的表达情况。结果 :与正常对照组相比 ,急性乙肝患者的Tc2细胞百分比增高 ,慢性乙肝患者的Th1、Tc1细胞百分比减低 ,也低于急性乙肝患者 ,但Th1、Tc1细胞百分比随着慢性乙型肝炎肝脏炎症活动的加剧而逐渐增多。分泌IL 4的Th、Tc细胞在正常人和各组病例中无显著性差异。结论 :急慢性乙肝患者的Th、Tc细胞均以分泌Th1型细胞因子占优势 ,但数量的差异可能是HBV感染者不同结局的原因之一。     

The nature of antigen in the eye has a profound effect on the cytokine milieu and resultant immune response

The eye is endowed with a number of mechanisms that protect it from immune-mediated injury. One such mechanism, termed anterior chamber-associated immune deviation (ACAID), evokes the antigen-specific, systemic down-regulation of Th1 responses to antigen inoculated into the anterior chamber of the eye. ACAID has been correlated with the selective production of IL-10 by the antigen-presenting cells (APC) and the development of a cross-regulatory Th2-like response. A small subset of antigens do not induce ACAID, but instead provoke IL-12 and normal Th1 immunity. Remarkably, all soluble antigens tested are capable of inducing ACAID; only cell-associated antigens do not induce ACAID. We hypothesized that the nature of antigen plays a decisive role in the resultant immune response. This hypothesis was tested with two well-characterized antigens, ovalbumin (OVA) and SV40 large T antigen (SV40 Lg T Ag). The soluble forms of OVA and SV40 Lg T Ag induced ACAID in both in vivo and in vitro models of the eye. In contrast, the particulate forms of these antigens, i. e. OVA passively absorbed onto inert latex beads (OVA-latex) and SV40 Lg T Ag expressed in two different cell lines, 99E1 and SV-T2, did not induce ACAID in either in vivo or in vitro models of the eye. In addition, the cytokine profiles of ocular APC pulsed with OVA or OVA-latex showed that soluble OVA induced the production of IL-10, whereas OVA-latex induced the production of IL-12. These data suggest that the nature of the antigen in the eye, whether soluble or particulate, is a crucial determinant in the resultant immune response. Moreover, they suggest a mechanism in which soluble antigens preferentially induce the release of ACAID-inducing IL-10 whereas particulate antigens preferentially induce the release of Th1-inducing IL-12 by responding APC.     

Defective Th1 and Th2 cytokine synthesis in the T-T cell presentation model for lack of CD40/CD40 ligand interaction

In this study, T or NK cell clones used as antigen-presenting cells (T- or NK-APC) were shown to be significantly less efficient than professional APC in inducing Th1 and Th2 cytokines by antigen-specific T cell clones. This phenomenon was not related to a limited engagement of TCR by T-APC, since comparable thresholds of TCR down-regulation were shown when antigen was presented by either T-APC or professional APC. Rather, the stimulatory T-APC weakness was due to their inability, because they are CD40⁻, to provide the appropriate co-stimuli to responder T cells both indirectly via IL-12, and partially via direct CD40L triggering on T cells. Indeed, the simultaneous addition of IL-12 and reagents directly engaging CD40L on responder T cells restored T cell cytokine synthesis when antigen was presented by T-APC. In addition, either IL-12 production or blocking of T cell cytokine synthesis by anti-IL-12 p75 antibodies was evident only when professional APC were used in our antigen-specific system. The down-regulation of cytokine synthesis in the system of T-T cell presentation could represent a novel mechanism of immune regulation, which may intervene to switch off detrimental Th1- or Th2-mediated responses induced by antigen presentation among activated T cells infiltrating inflamed tissues.     

Influence of both TCR repertoire and severity of the atopic status on the cytokine secretion profile of Parietaria officinalis -specific T cells

Peripheral blood mononuclear cells (PBMC) from both nonatopic and Parietaria officinalis -sensitive donors proliferated in response to the allergen Par o 1 and developed into Par o 1-specific T cell lines and clones, which also showed reactivity for Par o 1-derived peptides. Virtually all Par o 1-specific T cell lines and large numbers of Par o 1-specific T cell clones proliferated in response to two Par o 1 nonapeptides (p92 and p96), which probably contain immunodominant epitopes of the Par o 1 allergen. Both p92- and p96-specific T cell clones showed the ability to produce IFN-γ, but p92-specific T cell clones produced significantly lower amounts of IL-4 and IL-5 than p96-specific T cell clones, indicating that distinct epitopes, able to elicit functionally different T helper cell responses, may coexist in Par o 1. How ever, p92-specific T cell clones derived from atopic subjects with high IgE serum levels (high IgE producers) secreted significantly higher amounts of IL-4 and IL-5 than corresponding T cell clones generated from non atopic subjects or patients with low IgE serum levels (low IgE producers), whereas p96-specific T cell clones secreted high IL-4 and IL-5 concentrations irrespective of whether they derived from high or low IgE producers. The addition of IL- 4 and anti-IL-12 mAb to bulk culture significantly up-regulated the development of p92-specific T cells into IL-4-producing cells, whereas the addition of IL-12 and anti-IL-4 mAb shifted the differentiation of p96-specific T cells towards IFN-γ-producing cells. Taken together, these results suggest that the cytokine profile of allergen-specific T cells is influenced by both the T cell receptor repertoire and the severity of atopic status and can be modulated, at least in vitro, by stimulation with the specific peptide in the presence, or after removal, of appropriate cytokines.     

Plasmapheresis Modulates TH1/TH2 Imbalance in Patients with Systemic Lupus Erythematosus According to Measurement of Intracytoplasmic Cytokines

To examine the possible effect of plasmapheresis on the ratio of Th1/Th2 type cytokine-secreting cells we recruited eight patients with active systemic lupus erythematosus into the present study. They all failed to respond to conventional therapy. A sensitive multiparametric flow cytometric analysis was used for the detection of intracellular IL-4, IL-10 and IFN &#110 . Stimulated peripheral blood cells were analysed by this procedure. Plasmapheresis was performed every second day for three occasions, using a continuous flow type blood cell separator, and a total of 100 &#117 ml/body weight kg plasma was removed. Patients received 1 &#117 mg/kg/day methylprednisolone during this period. As a result of the procedure, the rate of IFN &#110 positive Th cells increased, while the rate of IL-4 and IL-10 expressing CD4 positive cells decreased. Together with these observations the concentration of anti-ds-DNA antibodies decreased after plasmapheresis. A decrease in disease activity index (SLE-DAI) indicated the clinical effectiveness of the therapy.     

Th1/Th2相关细胞因子基因检测方法的建立

目的：建立检测Ｔｈ１／Ｔｈ２相关细胞因子的方法。方法：设计６对用于ＩＬ－２、ＩＬ－４、ＩＬ－１０、ＩＬ－１３、ＩＦＮγ和β－ａｃｔｉｎ基因扩增的引物,建立可用于Ｔｈ１／Ｔｈ２相关细胞因子检测的ＲＴ－ＰＣＲ技术,同时 口平移法制备６种细胞因子的ｃＤＮＡ探针,建立ＲＮＡ斑点杂交技术。结果：用ＲＴ－ＰＣＲ和ＲＮＡ斑点杂交技术检测２０种肿瘤细胞株,发现１１／２０为Ｔｈ２型细胞因子表达,８／２０为Ｔｈ０型,     

Distribution of Th1, Th2, and Th0 and the Th1/Th2 cell ratios in human peripheral and endometrial T cells

PROBLEM: To examine whether normal pregnancy involves type 2 T-helper (Th2) immune condition or not. METHOD OF STUDY: We measured the percentage of Th0, Th1, and Th2 and the Th1/Th2 cell ratios of human peripheral blood and endometrial T cells using flow cytometry, which can analyze both the surface marker CD3, and intracellular cytokines, interleukin 4 (IL-4) and interferon gamma (IFNgamma). RESULTS: No significant differences were found in the percentages of Th1, Th2, and Th0 and the Th1/Th2 cell ratios in the peripheral blood T cells of nonpregnant women and women in early pregnancy. On the other hand, the percentage of Th1 cells was highest during the proliferative phase of the endometrium, followed by the secretory phase and early pregnancy decidua. The percentage of Th2 cells was highest in early pregnancy decidua and lowest during the proliferative phase of the endometrium. The Th1/Th2 ratio was 147.48+/-96.68 during the proliferative phase of the endometrium, 37.74+/-21.33 during the secretory phase, and 1.31+/-0.48 in the early pregnancy decidua. CONCLUSIONS: These data indicate that Th1 cells predominate in the nonpregnant endometrium, especially during the proliferative phase, while Th2 cells predominate in early pregnancy decidua.     

大鼠骨髓间充质干细胞和免疫调节作用

目的 研究一氧化氮(nitric oxide,NO)在骨髓间充质干细胞(mesenchymal stem cells,MSCs)的免疫调节作用.方法 贴壁筛选法分离培养Lewis大鼠骨髓间充质干细胞.以刀豆蛋白A(concanavalin A,ConA)作为刺激因素,SD大鼠外周血分离的T淋巴细胞作为反应细胞,采用CCK-8法检测T淋巴细胞与MSCs共培养后其增殖能力的变化.然后采用RT-PCR、Western blot检测MSCs诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)mRNA与蛋白的表达;Griess法检测上清液亚硝酸盐含量;ELISA检测上清液Th1细胞因子IFN-γ和Th2细胞因子IL-4的水平.结果 MSCs明显抑制ConA诱导的T淋巴细胞增殖,抑制作用因细胞比例的不同而有所区别.当实验组MSC:T为1:10时最明显,增殖率为(33.83±2.10)%,而1:80组[(78.62±3.80)%]与不含MSCs的阳性对照组[(79.03±1.70)%]差异无统计学意义(P＞0.05).实验组MSCs的iNOS mRNA与蛋白的表达以及上清液中亚硝酸盐含量均较阳性对照组明显上调,1:10～1:40的范围内呈明显递增趋势,但1:80组与1:40组差异无统计学意义(P＞0.05).在加入iNOS特异性抑制剂2-甲基-2-巯基硫酸脲(S-methylisothiourea sulfate,SMT)后,各组T淋巴细胞增殖率基本恢复.实验组IFN-γ含量随MSCs所占比例的降低而增加,各组IL-4含最差异无统计学意义(P＞0.05).结论 MSCs对同种异体外周血T淋巴细胞的增殖有免疫调节作用,机制可能与其分泌的可溶性因子NO影响了 Th1/Th2平衡有关.

Abstract：

Objective To observe the role of nitric oxide(NO) in the immune regulatory effect of bone marrow mesenchymal stem cells(MSCs). Methods Bone marrow MSCs were isolated from Lewis rats by adherence screening. Concanavalin A (ConA) was adopted as the stimulator and T-lymphocyte isolated from peripheral blood of SD rats as the reactive cells. The changes of the ability of T-lymphocyte proliferation, when co-cultured with MSCs, were measured by CCK-8 assay. The inducible nitric oxide synthase (iNOS) mRNA and protein expression on MSCs and were detected by RT-PCR, Western blot. The contents of nitrites and the levels of Th1 type cytokine IFN-γand Th2 type cytokine IL-4 were measured by Griess test and ELISA respectively, in the co-cultured supernatant. Results T-lymphocyte proliferation was inhibited by co-cultured MSCs, which was concentration-dependent. In this study, the inhibition was most obviously group[ (79.03 ± 1.70)% ] (P ＞ 0.05 ). The I NOS mRNA expression, protein and nitrite levels were signifigroups, the proliferation rate of T-lymphocyte recovered. The content of IFN-γwas increased with the ratio decline of MSCs in the experimental group and IL-4 in each group has no significant difference( P ＞ 0.05 ).Conclusion MSCs inhibited T-lymphocyte proliferation by influencing Th1/Th2 balance, and the secretion of soluble factor NO, which secreted by MSCs, may plays an important role in the immune regulation.     

Altered Th1/Th2 balance associated with the immunosuppressive/protective effect of the H-2Ab allele on the response to allo-4-hydroxyphenylpyruvate dioxygenase

The H-2A^b allele exerts a dominant down-regulatory effect on the anti-allo-HPPD (4-hydroxyphenylpyruvate dioxygenase) antibody response, through a hitherto unknown mechanism. In the present study, the allo-variable peptide bound to responder H-2A^k molecules with higher affinity than to H-2A^b ones, arguing against the operation of an affinity hierarchy. Quantitative polymerase chain reaction revealed differences in cytokine mRNA expression between suppressed and high-responder mice. Lymph node cells of responder but not suppressed mice contained high levels of interleukin (IL)-4 mRNA as early as 11 h post-immunization and continued to do so for at least 8 days; this early burst was paralleled by a small burst in transforming growth factor (TGF)-β mRNA level. Differences in IL-12 mRNA were not detected, although an early IL-12 effect could not be excluded. Interferon (IFN)-γ appeared to contribute to the suppression at later time points. Early treatment of responder mice with anti-IL-4 monoclonal antibody (11B11) down-regulated the antibody response. The proliferative T cell response from hyperimmunized mice was reduced but still detectable in the presence of an H-2A^b allele. Thus, in the presence of this allele, the Th1 response is enhanced and that of Th2 cells suppressed, apparently as a result of the bias of H-2A^b-restricted T cells in favor of the Th1 subset.     

Selective stimulation of T helper 2 cytokine responses by the anti-psoriasis agent monomethylfumarate

Type 2 cytokines are thought to have a protective role in psoriasis vulgaris by dampening the activity of T helper 1 (Th1) lymphocytes. The aim of the present study was to determine the effect of monomethylfumarate (MMF), the most active metabolite of the new anti-psoriatic drug Fumaderm®, on the production of cytokines and the development of Th subsets. MMF was found to enhance interleukin (IL)-4 and IL-5 production by CD2/CD8 monoclonal antibody-stimulated peripheral blood mononuclear cells (PBMC) in a dose-dependent manner. Maximal effects of MMF were found at a concentration of 200 μM and resulted in tenfold enhanced levels of IL-4 and IL-5 production. MMF did not affect the levels of IL-2 production, interferon (IFN)-γ production or proliferative T cell responses in these cultures. Similar effects of MMF were observed in cultures of purified peripheral blood T cells indicating that this compound can act directly on T cells. MMF did not influence cytokine production by purified CD4⁺CD45RA⁺ (unprimed) T cells, but greatly enhanced IL-4 and IL-5 production without affecting IFN-γ production by purified CD4⁺CD45R0⁺ (primed) T cells. Furthermore, MMF also augmented IL-4 and IL-5 production in established Th1/Th0 clones that were stimulated with CD2/CD28 monoclonal antibody. Finally, when PBMC were challenged with Mycobacterium tuberculosis that typically induces Th1 recall responses with strong IFN-γ secretion, MMF again appeared to induce high levels of IL-4 and IL-5 secretion while IFN-γ production was unaffected. These results may be relevant for the development of therapeutic regimens designed to correct inappropriate Th1 subset development in immunopathologic conditions.     

自体细胞因子诱导的杀伤细胞联合常规化疗治疗中晚期宫颈癌的临床研究

目的 探讨回输自体细胞因子诱导的杀伤细胞(CIK)联合顺铂治疗中晚期宫颈癌的临床疗效,并观察此治疗对患者外周血中Th1/Th2细胞因子的漂移的影响.方法 将我院在2013年2月至2014年2月接收的宫颈癌患者44例,随机分为单纯化疗组(n=22)和联合治疗组(n=22),并选取健康的女性个体20例作为对照组,采用酶联免疫吸附(ELISA)法检测检测所有样本外周血中Th1型细胞因子白细胞介素(IL)-2、干扰素-γ(IFN-γ)的表达水平,Th2型细胞因子IL-4、IL-6、IL-10的表达水平,流式细胞仪检测Th1/Th2细胞的比率变化.同时评价两组患者疗效及生活质量.结果 与健康对照组比较,治疗后两组患者血清中Th1型细胞因子IL-2、IFN-γ的浓度显著升高,且联合治疗组升高程度高于单纯化疗组,而Th2型细胞因子IL-4、IL-6、IL-10的浓度明显降低,且联合治疗组降低程度高于单纯化疗组(P＜0.05).治疗后单纯化疗组和联合治疗组Th1/Th2比率小于对照组,但联合治疗组高于单纯化疗组(P＜0.05).联合治疗组完全缓解率高于单纯化疗组(36.4％比22.7％,P＜0.05).联合治疗组有效率高于单纯治疗组(90.9％比72.7％,P＜0.05).联合治疗组的生活质量总提高率高于单纯化疗组(86.4％比72.7％,P＜0.05).结论 自体CIK细胞联合常规化疗能够改善中晚期宫颈癌的Th1向Th2漂移,是安全并且有效的.     

Intracellular cytokine production in peripheral blood lymphocytes: a comparison of values in infertile and fertile women

Citation
Horká P, Jaro?ová R, Malí?ková K, Janatková I, Mare?ková H, Zima T, Kalousová M. Intracellular cytokine production in peripheral blood lymphocytes: a comparison of values in infertile and fertile women. Am J Reprod Immunol 2011; 65: 466–469 Problem To analyze the relation of the fertility and pregnancy of women of childbearing age to the intracellular (IC) production of tumor necrosis factor alpha (TNF‐α), interferon gamma (IFN‐γ), and interleukins 2 and 4 (IL‐2 and IL‐4). Method of study Intracellular cytokine production in peripheral blood CD3⁺ CD4⁺ lymphocytes was analyzed by flow cytometry in 185 women being treated for infertility and 50 fertile women of childbearing age. Results Infertile women have a significantly higher IC production of TNF‐α, IFN‐γ, IL‐2, and IL‐4 and higher ratios of TNF‐α/IL‐2, TNF‐α/IL‐4, and TNF‐α/IFN‐γ compared to the fertile women. Conclusion Cytokines produced by Th lymphocytes are important in orchestrating the immune response during conception, and Th‐cell dysregulation could be a reason for infertility.     

青藤碱对T淋巴细胞活化及TH1类细胞内细胞因子表达的影响

目的：深入研究青藤碱对T淋巴细胞Thl类细胞因子表达的影响。方法：分离小鼠淋巴结细胞，加入不同浓度的青藤碱作用1小时后，加多克隆刺激剂PDB和离子霉素，继续培养4小时后收获细胞，进行细胞内细胞因子染色，以流式细胞术对T细胞Th1类细胞因子TNF-γ、炎症性细胞因子TNF-α分子表达情况进行分析；同时，观察药物对T细胞活化早期标志CD59表达的影响；结果：1000μmol／L(329．24μg/ml)青藤碱能够抑制CD69表达，200μmol/L青藤碱对CD69表达无影响；200、1000、2000μmol／L青藤碱能够剂量依赖性地显著降低T细胞内细胞因子TNF-γ、TNF-α分子表达。结论：抑制T细胞活化异常可能是青藤碱治疗类风湿关节炎免疫药理机制之一，此抑制效应可能主要不是通过影响PKC而是与影响钙离子依赖的T细胞活化信号传导途径相关。     

Intracellular production of IL-2, IL-4 and IFN-γ by peripheral blood CD3+ cells in intermittent allergic rhinitis

Background: Allergic inflammation is mainly driven by type 2 T helper cells. The aim was to assess the changes in production of type 1 and 2 cytokines by CD3⁺ T cells dependent on natural exposure to allergens in subjects with intermittent allergic rhinitis (IAR) and in non-atopic subjects.Material: A total of 13 patients with IAR and 13 healthy non-atopics were recruited into the study. 11 patients with IAR were examined during the grass pollen season and 11 patients outside the season, 9 of them were assessed on both occasions.Methods: A flow cytometric assessment of intracellular expression of IL-2, IL-4 and IFN- by CD3⁺ cells was performed. For statistical analysis non-parametric tests were used.Results: A tendency to decreased production of IL-4 outside the season was observed (6.94% [3.42–13.33] in season vs. 2.06% [0.7–3.6] out of season). The production of IL-4 was higher in the rhinitic group in the season than in the control group (1.93% [1.07–4.97], p = 0.0034) and production of IL-2 was higher both in and outside the season (9.1% [3.94–15.09] and 10.0% [4.79–25.35] vs. 3.64% (2.64–5.03), p = 0.037 and 0.045, respectively). IL-4/IL-2 and IL-4/IFN- ratios were higher in the IAR group in the season than outside the season.Conclusion: A tendency towards a switch from a predominant type 2 response during natural allergen exposure to its suppression outside the season was found, together with a stable type 1 response.Received 22 July 2004; returned for revision 27 August 2004; accepted by M. J. Parnham 2 November 2004