外周血单个核细胞端粒酶活性及IL-2、IL-12水平与老年性肺炎关系的研究

目的:探讨外周血单个核细胞(PBMC)端粒酶活性及其分泌IL-2、IL-12水平与老年性肺炎的关系。方法:利用ELISA法和PCR-ELISA法,分别检测对照组与成年肺炎组、老年肺炎组治疗前与恢复期外周血单个核细胞端粒酶的活性及其培养液上清中IL-2和IL-12水平。结果:肺炎组治疗前、后IL-2与IL-12水平均高于对照组(P<0.05);肺炎组治疗后IL-2与IL-12水平较治疗前下降(P<0.05);恢复期IL-12水平老年肺炎组高于成年肺炎组(P<0.05);成年肺炎组治疗前端粒酶活性高于对照组(P<0.01),老年肺炎组端粒酶活性治疗前、后均低于对照组(P<0.05)。结论:外周血单个核细胞端粒酶活性及培养分泌的IL-2、IL-12参与老年性肺炎患者保护性免疫应答。     

Effects of Peripheral Blood Mononuclear Cells Morphology on Vascular Calcification in Uremic Patients on Maintenance Hemodialysis

We used high‐resolution atomic force microscopy (AFM) to examine possible changes in the morphology of peripheral blood mononuclear cells (PBMCs), and to investigate their influence on vascular calcification in uremic patients on maintenance hemodialysis (MHD). 36 uremic patients had cardiovascular diseases after MHD (MHD group1) and 30 uremic patients did not (MHD group 2), and 20 healthy volunteers were the control group. The extent of coronary artery calcification was assessed with coronary artery calcification score (CACS). AFM was used to analyze PBMCs nuances. Concentrations of bone morphogenetic protein‐2 (BMP‐2) in PBMC supernatants were detected by ELISA. Protein expressions of BMP‐2 were measured by Western blot. No significant differences in PBMC morphology were observed among groups by light microscopy. AFM images revealed that uremic patients exhibited significant differences of PBMC morphology and vascular calcification when compared with healthy volunteers. The PBMCs in uremic patients were larger in volume, mean height, half‐maximum amplitude, average roughness and higher concentrations and expression of BMP‐2 and CACS (P < 0.05), with granular processes or caveolae of uneven size distributed over cell surfaces. These differences were also significant between MHD group 1 and group 2 (P < 0.05). PBMC volume, mean height, half‐maximum amplitude, and average roughness were positively correlated with BMP‐2 and CACS. Moreover, the correlation PBMC with BMP‐2 was higher than with CACS. PBMC morphology in MHD patients was related to the degree of vascular calcification. The larger mean height, half‐maximum amplitude, average roughness and cell volume were, the higher degree of vascular calcification was.     

Enhanced Neutrophil Apoptosis in Neutropenic Patients with Hepatosplenic Schistosomiasis: Evidence of Serum Fas Ligand

Enhanced neutrophil apoptosis has been reported in neutropenic hepatosplenic schistosomiasis. The shortening of neutrophil survival via apoptosis may explain the neutropenia that occur in these patients. However, the regulation of neutrophil apoptosis in hepatosplenic schistosomiasis has not been clearly defined. Neutrophils harvested from neutropenic patients with hepatosplenic (HS) schistosomiasis, (n=25), non-neutropenic patients with hepatointestinal (HI) schistosomiasis (n=10), and age-/gender-matched healthy control subjects (n=10) were incubated with autologous serum. Neutrophils apoptosis was quantified by flow cytometry through determination of propidium iodide nuclear staining and confirmed by DNA gel electrophoresis at 0 (i.e. fresh neutrophils), 4 and 24 h culture. Neutrophils from healthy subjects were also incubated with either 10% heterologous normal or neutropenic serum, with and without anti-Fas ligand antibody. Fas expression was assessed in fresh neutrophils using flow cytometry. Compared with normal healthy neutrophils, and HI neutrophils, neutropenic neutrophils demonstrated greater apoptosis in the presence of autologous serum (P<0.01, 0.05, respectively). Furthermore, compared with normal neutrophils exposed to heterologous normal serum, those exposed to heterologous neutropenic serum exhibited higher apoptosis rates ( P<0.01). Moreover, anti-Fas L antibody attenuated the neutropenic serum-induced neutrophil apoptosis in normal neutrophils. Fas expression was significantly higher in the neutropenic group when compared to both HI and normal healthy controls (P<0.05). In addition, Fas expression by neutrophils was paralleled by high neutrophil apoptosis. On the other hand, neutrophil apoptosis was not correlated to the size of spleen in neutropenic group.

In conclusion, the rate of neutrophil apoptosis is accelerated in patients with neutropenic hepatosplenic schistosomiasisis. These findings suggest that the enhanced neutrophil apoptosis that occurs in neutropenic HS patients is triggered by a serum factor, which is mostly a Fas ligand.     

Persistence of Hepatitis C Virus in Peripheral Blood Mononuclear Cells of Sustained Viral Responders to Pegylated Interferon and Ribavirin Therapy

The aim of this paper was to assess the persistence of hepatitis C virus (HCV) among patients successfully treated with peginterferon and ribavirin. The persistence of viral RNA was evaluated in the serum and peripheral blood mononuclear cells (PBMCs) of 25 chronic hepatitis C patients with sustained viral response to peginterferon and ribavirin treatment up to 56 months after the completion of therapy. Viral RNA was detected in the peripheral blood mononuclear cell cultures of five patients (20%), but none had detectable serum HCV RNA. At present, the clinical relevance of this finding is unclear. It is possible that viral persistence and, specifically, the presence of HCV RNA in PBMCs may lead to HCV reactivation under special circumstances, such as immunosuppression.     

反转录─多聚酶链反应技术定量检测人外周血单个核白细胞低密度脂蛋白受体基因的表达

人外周血单个核白细胞低密度脂蛋白受体的ｍＲＮＡ为低丰度表达，不易检出，本文应用反转录－多聚酶链反应技术建立的低密度脂蛋白受体基因表达定量检测法灵敏、简捷、特异。为临床观察高胆固醇血症患者和冠心病易患人群的低密度脂蛋白受体表达情况，提供了方便必要的手段，初步应用结果表明，高胆固醇血症和冠心病患者的低密度脂蛋白受体ｍＲＮＡ水平明显降低。     

A Comparative Study of a New,Fully Automated Procedure and the Standard Mononuclear Cell Program Using the Cobe Spectra for Peripheral Blood Stem Cell Collection

Abstract: Recently, a completely automated procedure, the AutoPBSC program for the COBE Spectra cell separator, has been developed for peripheral blood stem cell harvest (PBSCH). We compared the performance of the AutoPBSC program with the standard mononuclear cell (MNC) program in the same patients and in a donor. Peripheral blood stem cells (PBSC) were collected from 3 patients or a donor alternately using the MNC program and the AutoPBSC program in a course of PBSC mobilization. Equal blood volume was processed from each patient (200 ml/kg) and a donor (150 ml/kg). We used a harvest volume of 3 ml and a chase volume of 7 ml in all AutoPBSC procedures. The procedure duration was almost equivalent for both programs. The volume of products was significantly lower in the AutoPBSC program (71′± 13 ml) than in the MNC program (183 ± 30 ml). MNC yields were fewer, and total nucleated cell (TNC) and MNC collection efficiency was less for the AutoPBSC program compared to the MNC program. The CD34 + cell collection efficiency was less for the AutoPBSC program (26.5 ± 13.7%, compared with 77.7 ± 60.6%; p > 0.05). The contamination of platelets and red cells was significantly less in the AutoPBSC program than in the MNC program. In conclusion, we consider that the collection efficiency in the new program should be improved by modification of parameters because there exist great advantages to automated procedures.     

Peripheral Blood Stem Cell Collection after Intermediate-Dose Cytarabine in Adult Patients with Acute Myeloblastic Leukemia Undergoing Autologous Blood Stem Cell Transplantation in First Complete Remission

Different strategies for collecting peripheral blood stem cells (PBSC) for autologous blood stem cell transplantation (ABSCT) have been reported for patients with acute myeloblastic leukemia (AML). We compared the clinical results of 2 consecutive protocols in 75 adult patients with AML in first complete remission who underwent ABSCT. In the first 56 patients (group A), PBSC were collected after induction and/or consolidation chemotherapy courses. In the subsequent 19 patients (group B), PBSC collection was done after a further intensification course with intermediate-dose cytarabine and mitoxantrone. Hematopoietic engraftment was similar in the 2 groups, with the median times to reach 0.5 x 10(9) neutrophils/L and 20 x 10(9) platelets/L being 13 days each in group A, and 12 days and 24 days, respectively, in group B. There were 3 graft failures (all in group A) and 5 transplantation-related deaths (6.6%, 4 in group A and 1 in group B). Although not statistically significant, the 3-year probabilities of both relapse (31% versus 66%; P = .12) and disease-free survival (60% versus 36%; P = .1) compared favorably for group B. Our study suggests that collection of PBSC after additional intensification can result in a better outcome for AML patients who undergo ABSCT.     

Apoptosis in the intestinal mucosa of patients with inflammatory bowel disease: evidence of altered expression of FasL and perforin cytotoxic pathways

Background and aims Abnormal apoptosis may result in the persistence of activated intestinal T-cells in inflammatory bowel disease (IBD). We investigated apoptosis in distinct mucosal compartments, and the expression of Fas/Fas ligand and perforin in the inflamed and non-inflamed intestinal mucosa of patients with IBD.Methods Colon specimens from 15 patients with ulcerative colitis (UC) and inflamed and non-inflamed mucosa from 15 patients with Crohns disease (CD) were analysed for densities and distribution of apoptotic cells determined by the terminal deoxynucleotidyltransferase-mediated dUDP-biotin nick-end labelling (TUNEL) method. Fas, FasL, and perforin-expressing cells were assessed by immunoperoxidase, and with anti-CD3, anti-CD20 and anti-CD68, by double immunofluorescence with confocal microscopy. Quantitative analysis was performed using a computer-assisted image analyser.Results Colonic lamina propria (LP) and epithelium from patients with UC showed higher rates of apoptosis than controls, but no difference was shown regarding patients with CD. In LP, co-expression of Fas was reduced with T-cells in inflamed CD mucosa, and with macrophages in all patients with IBD. No difference was found in the expression of Fas on B-cells. Rates of FasL-expressing cells in LP were higher in IBD than in controls, with no correlation with the rates of apoptosis. Rates of perforin-expressing cells in LP were greater in UC than in controls, and correlated to the rates of apoptosis. No difference was shown regarding the inflamed and non-inflamed CD mucosa. Rates of FasL and perforin-expressing intra-epithelial lymphocytes showed no difference among groups.Conclusions Increased expression of FasL in IBD colonic LP not parallelled by Fas on T-cells and macrophages may indicate a reduced susceptibility to the Fas/FasL-mediated apoptosis of lymphoid cells. Expression of perforin is correlated to the tissue damage, and may represent the enhancement of a distinct cytotoxic pathway in UC.Heitor S.P. Souza and Claudio J.A. Tortori contributed equally to this paper     

Assessment of Neutrophil Apoptosis Ex Vivo in Hepatosplenic Patients with Neutropenia Pre and Post Splenectomy

The pathophysiology of neutropenia seen in patients with schistosomiasis or hepatitis C infection that complicates the course of liver disease is poorly understood. We evaluated the neutrophil apoptosis before and after splenectomy to clarify the role of apoptosis and splenomegaly in the occurrence of neutropenia. Neutrophils were isolated from 23 hepato-splenic patients with neutropenia, 8 hepatosplenic patients with normal neutrophil counts, 7 patients who were post splenectomy, and a further ten normal control subjects. These were cultured for 24 h and the time course of neutrophil apoptosis was assessed by determination of Annexin V and propidium iodide binding by flow cytometry. Fas and Bcl2 expression were determined on fresh neutrophils using flow cytometry. Levels of tumor necrosis factor alpha, interleukin 3, and gamma interferon were evaluated using an immunosorbent assay.

Neutrophil apoptosis was minimal in the fresh neutrophils, however, cultured neutrophils exhibited significantly greater apoptosis in neutropenic patients when compared to non-neutropenic patients (P=0.01 at 4 h and P<0.05 at 24 h) and control group (P<0.01 at 4 h and 24 h). After splenectomy, the percentage of neutrophil apoptosis declined to the normal control levels (P>0.05). Fas and Bcl2 expression on neutrophil were significantly higher in the neutropenic group as compared to normal controls (P<0.05, P=0.01 respectively). Serum TNF alpha, IL-3, and IFN gamma levels were not significantly different in all studied groups.

In conclusion: Neutrophils from neutropenic hepatosplenic patients exhibit markedly accelerated apoptosis, which is normalized after splenectomy. Thus increased neutrophil apoptosis may in part be responsible for the occurrence of neutropenia.     

Prevalence of Occult Hepatitis B Virus in Plasma and Peripheral Blood Mononuclear Cell Compartments of Patients With Chronic Hepatitis C Infection in Tehran-Iran

Background

Occult hepatitis B virus (HBV) infection (OBI) is frequently reported in patients with chronic hepatitis C virus (HCV) infection. An association between OBI and more liver damage, cirrhosis, hepatocellular carcinoma, and reduced response to interferon therapy in patients with HCV infection is suggested.

Objectives

The aim of this study was to determine the prevalence of occult HBV, and evaluate its clinical influence on patients with chronic HCV.

Patients and Methods

A cohort study including50 patients with positive results for HCV, and negative results for HBsAg tests was performed. The patients were divided into two groups: one group had positive results for both HCV and occult HBV tests (n = 18), and the other had positive results for HCV, but negative findings for occult HBV (n = 32). All were treated with PEG-IFN alpha-2a and Ribavirin. Presence of HCV RNA was followed in these patients.

Results

HBV-DNA was detected using nested-PCR in 20% of plasma and 32.6% of peripheral blood mononuclear cell (PBMC) compartments. No significant differences were observed between patients with and without occult HBV for sex, age, duration of HCV infection, histological markers, presence of anti-HBc, HCV viral load, and HCV genotype. The response rate was significantly higher in patients with positive results for HBV-DNA test compared to those with negative findings (100% vs. 71.9 %, P < 0.05).

Conclusions

In conclusion, occult HBV was found in 36% of patients with negative results for HBsAg, but positive results for HCV. Detection of HBV-DNA in both PBMCs and plasma together in comparison with plasma alone provided more true identification of OBI.The SVR rate was significantly higher in coinfected patients than mono-infected ones.     

Clinical Implication of Protein Levels of IL-5 in Induced Sputum in Asthmatic Patients

To determine whether protein levels of interleukin-5 (IL-5) in induced sputum reflect the degree of eosinophilic inflammation, we evaluated the role of IL-5 on clinical characteristics in stable asthmatic patients. IL-5 level, differential eosinophil count, and level of eosinophil cationic protein (ECP) in induced sputum were all significantly higher for asthmatics than for normal controls. Both eosinophil counts and ECP levels in induced sputum were inversely correlated with the degree of airflow limitation (FEV₁/FVC). In addition, patients with measurable IL-5 in sputum had significantly more eosinophils, higher levels of ECP in sputum, and lower FEV₁ (percent predicted) than did patients with levels of IL-5 beneath the limit of detection. However, we found no significant difference in IL-5 levels between atopic and nonatopic asthmatics. IL-5 level in induced sputum is a good indicator of eosinophilic inflammation in atopic and nonatopic asthmatic patients.     

脂质体介导姜黄素抑制Bel-7402细胞增殖和诱导其凋亡的作用

目的:研究提高姜黄素治疗肝癌生物学效应的新技术和新方法.方法:对比观察脂质体-姜黄素水溶制剂对人肝癌细胞(Bel-7402)凋亡及凋亡相关调控基因Bax、Bcl-2的影响.MTT(四甲基偶氮唑蓝)法观察脂质体-姜黄素对Bel-7402细胞增殖的抑制作用.原位末端标记法(TUNEL技术)观察脂质体-姜黄素诱导Bel-7402细胞凋亡的作用.免疫组织化学染色(SABC)法检测脂质体-姜黄素对Bax和Bcl-2基因表达的影响.结果:10μg/ml、5μg/ml、2.5μg/ml脂质体-姜黄素对Bel-7402细胞增殖有显著抑制作用,P＜0.01,其抑制率分别为38.67%、26.67%和17.33%,与同浓度的姜黄素的抑制率(29.33%、20.00%、5.33%)比较,差异有显著性意义(P＜0.05);增殖抑制作用随药物浓度增高而有加强趋势,3个有效浓度组间差异均有显著性意义(P＜0.05).10μg/ml、5μg/ml、2.5μg/ml脂质体-姜黄素处理组Bel-7402细胞凋亡率分别为68.9%、43.4%、26.9%,与同浓度姜黄素组的Bel-7402细胞凋亡率(53.3%、30.2%、14.9%)比较,差异有显著性意义(P＜0.05).脂质体-姜黄素对细胞凋亡相关基因Bax、Bcl-2表达的影响,与对照组比较差异无显著性意义.结论:脂质体能显著提高姜黄素对Bel-7402细胞增殖的抑制和诱导其凋亡的作用.脂质体-姜黄素对Bax、Bcl-2的表达无显著影响.     

Immune Modulator Pidotimod Decreases the In Vitro Expression of CD30 in Peripheral Blood Mononuclear Cells of Atopic Asthmatic and Normal Children

Recurrent viral infections are frequently observed in children with atopic asthma. In this study we investigated the ability of the synthetic immunomodulator pidotimod to affect in vitro the phenotype and/or cytokine profile of blood cells in relation to atopic asthma. Peripheral blood mononuclear cells were isolated from 13 atopic asthmatic and 9 normal children and stimulated in culture with mitogen either in the presence or not of the drug. Expression of surface markers was evaluated by flow cytometry, and production of interleukin-4 and interferon-gamma was measured in supernatants. Pidotimod was able to down-regulate the expression of CD30 on cells from both atopic and normal subjects. Because CD30 has been associated with Th-2 cells, this observation supports the possibility of pidotimod being able to affect the Th-1/Th-2 balance in atopic asthma.     

The Determination of Mineralocorticoid Receptors in Human Mononuclear Leukocytes from Patients with Mineralocorticoid Excess: Physiological and Pathological Implications

The affinity and the capacity of mineralocorticoid receptors (MR) in human mononuclear leukocytes (HML) were determined in 9 patients with Conn's syndrom (PA) and in 3 patients with pseudohypoaldosteronism (PHA). The number of binding sites per cell was 136±39 (mean±SD) in PA. One case with PHA had no MR, and of the other 2 patients, one had 50 and the other 55 receptors per cell. The capacity of normal controls ranged from 200 to 400 receptors per cell (n=20). We conclude that (1) the etiogy of PHA is due to a lack of MR in the target tissues and that (2) a down regulation of MR may exist in PA.     

Influential Factors for the Collection of Peripheral Blood Stem Cells and Engraftment in Acute Myeloid Leukemia Patients in First Complete Remission

Although several studies have investigated factors influencing peripheral blood stem cell (PBSC) mobilization in patients with nonmyeloid malignancies in an effort to increase the efficiency of autologous PBSC transplantation (APBSCT), there are very few reports on the efficiency of PBSC mobilization in patients with leukemia. We analyzed the effects of influential variables on successful mobilization and the correlation between infused cell doses and engraftment in acute myeloid leukemia (AML) patients in first complete remission (CR1) who received APBSCT. Between May 1998 and May 2003, 34 patients with AML underwent APBSC collections at our institution. All patients were in CR1 at the time of transplantation. Except for 1 patient, all patients successfully achieved the target CD34(+) cell yield of > or = 2 x 10(6)/kg. Among progenitor cells, the CD34(+) cell dose and the colony-forming unit-granulocyte-macrophage count showed significant correlations with neutrophil and platelet engraftments. The time to neutrophil engraftment was inversely correlated to the number of infused CD34(+) cells (r = -0.67; P < .001), whereas the time to neutrophil engraftment was not significantly correlated with the number of monocytes (r = 0.20; P = .701) or the number of nucleated cells (r = 0.35; P = .062). The time to platelet engraftment was significantly correlated with the dose of infused CD34(+) cells (r = -0.47; P = .012). The univariate analysis showed that more CD34(+) cells per kilogram and more CD34(+) cells per kilogram per day were collected from patients who had a shorter interval (less than 2 months) between diagnosis and PBSC harvest (P = .0111). In conclusion, this study showed that the CD34(+) cell dose was most strongly correlated with a successful engraftment in AML CR1 patients who underwent APBSCT. The proper timing of PBSC collections should be explored to optimize the outcome of APBSCT in AML CR1 patients.     

慢性乙型肝炎病人血清及外周血单个核细胞培养上清液白细胞介素-10的检测及其临床意义

目的探讨慢性乙型肝炎（ＣＨＢ）病人血清及外周血单个核细胞（ＰＢＭＣ）培养上清液白细胞介素一１０（ＩＬ－１０）检测的临床意义。方法分离１５例ＣＨＢ病人及６名正常人血清及ＰＢＭＣ。ＰＢＭＣ体外单独或与金黄色葡萄球菌场毒素Ｂ（ＳＥ）或重组ＨＢｃＡｇ（ｒＨＢｃＡ）共培养４８小时后,用双抗体夹心ＥＬＩＳＡ方法检测血清及ＰＢＭＣ培养上清液ＩＬ－１０水平。结果ＣＨＢ病人血清ＩＬ－１０水平为（１２３．１１±１３．８９）ｎｇ／Ｌ,正常对照组平均为（９５．９７±１１．６８）ｎｇ／Ｌ,两者之间差异有非常显著性,Ｐ＜０．０１。ＰＢＭＣ体外培养４８小时,培养上清液中ＩＬ－１０水平均明显高于正常对照组,Ｐ＜０．０１。其中ｒＨＢＣＡｄｅ导病人ＰＢＭＣ产生的ＩＬ－１０水平最高,达（３６９．５±３０．５２）ｎｇ／Ｌ。ＨＢＶＤＮＡ阳性病人血清及ＰＢＭＣ培养上清液ＩＬ－１０水平均明显高于ＨＢＶＤＮＡ阴性组病人。慢性轻度和中度肝炎病人血清及ＰＢＭＣ培养上清液ＩＬ－１０水平又高于慢性重度或慢性重型肝炎病人。结论ＣＨＢ病人血清及ＰＢＭＣ培养上清液ＩＬ－１０水平升高可能与ＨＢＶ持续感染有关。     

血管内皮生长因子对过氧化氢诱导的内皮细胞凋亡的影响及其机制

目的研究血管内皮生长因子对过氧化氢诱导的血管内皮细胞凋亡的影响,同时检测凋亡相关基因Bcl-2 mRNA与Fas mRNA表达的变化。方法体外培养人脐静脉内皮细胞,随机分成对照组、过氧化氢组和过氧化氢 血管内皮生长因子组,12 h后,采用原位末端标记法和流式细胞仪分别观察各组细胞的凋亡数和凋亡率,通过逆转录聚合酶链反应观察各组细胞中凋亡相关基因Bcl-2 mRNA与Fas mRNA表达的变化。结果过氧化氢组凋亡细胞数(27.83±2.14)明显高于对照组(2.50±1.05)(P<0.01)和过氧化氢 血管内皮生长因子组(13.00±2.10)(P<0.01)。过氧化氢组细胞凋亡率(14.17%±0.45%)明显高于对照组(1.55%±0.87%)(P<0.01)和过氧化氢 血管内皮生长因子组(5.69%±0.38%)(P<0.01)。与过氧化氢组比较,过氧化氢 血管内皮生长因子组Fas mRNA表达明显减少(40.67%±2.16%比94.50%±3.45%,P<0.01),而Bcl-2 mRNA表达明显增加(60.33%±1.75%比23.17%±1.17%,P<0.01)。结论血管内皮生长因子能拮抗过氧化氢诱导的内皮细胞凋亡,其抗凋亡的机制可能与上调Bcl-2 mRNA表达与下调Fas mRNA表达有关。     

Seasonal Variations of T-Cell Cytokine Pattern in Peripheral Blood from Atopic Subjects

Previous studies on the effect of seasonal exposure to the sensitizing antigen on T-cell cytokine pattern from atopic subjects evaluated T-cell cytokine production by titration in the serum or culture supernatants. The purpose of this study was to determine the seasonal variations of T-cell cytokine pattern from atopic subjects at the single-cell level. We examined the interleukin-4 (IL-4) and interferon -γ expression in peripheral blood CD4+ and CD8+ T cells from 11 subjects with grass-pollen-sensitive allergy before and during the 1999 grass pollen season using a flow cytometric method of intracellular cytokine detection. Eight healthy volunteers served as the control group. Flow cytometric analysis of peripheral blood lymphocytes showed no seasonal variations of IL-4- and interferon-γ-producing T cells in atopic subjects. However, there was a decreased percentage of IL-4-producing cells among peripheral blood CD4+ and CD8+ T cells from the atopic subjects both during and outside the pollen season in comparison to the controls. We did not find seasonal variations of T-cell cytokine pattern in peripheral blood from atopic subjects. However, we observed a decreased percentage of IL-4-producing T cells in peripheral blood from these subjects in comparison to healthy controls. These data add to the view of a continuous migration of T helper 2 (TH2) cells from the blood to the tissues of primary allergen exposure.