The Broad Immunomodulatory Effects of IL-7 and Its Application In Vaccines.

Interleukin-7 (IL-7) is produced by stromal cells, keratinocytes, and epithelial cells in host tissues or tumors and exerts a wide range of immune effects mediated by the IL-7 receptor (IL-7R). IL-7 is primarily involved in regulating the development of B cells, T cells, natural killer cells, and dendritic cells via the JAK-STAT, PI3K-Akt, and MAPK pathways. This cytokine participates in the early generation of lymphocyte subsets and maintain the survival of all lymphocyte subsets; in particular, IL-7 is essential for orchestrating the rearrangement of immunoglobulin genes and T-cell receptor genes in precursor B and T cells, respectively. In addition, IL-7 can aid the activation of immune cells in anti-virus and anti-tumor immunity and plays important roles in the restoration of immune function. These biological functions of IL-7 make it an important molecular adjuvant to improve vaccine efficacy as it can promote and extend systemic immune responses against pathogens by prolonging lymphocyte survival, enhancing effector cell activity, and increasing antigen-specific memory cell production. This review focuses on the biological function and mechanism of IL-7 and summarizes its contribution towards improved vaccine efficacy. We hope to provide a thorough overview of this cytokine and provide strategies for the development of the future vaccines.

Intrathymic differentiation of natural antibody-producing plasma cells in human neonates.

The thymus is a central lymphoid organ primarily responsible for the development of T cells. A small proportion of B cells, however, also reside in the thymus to assist negative selection of self-reactive T cells. Here we show that the thymus of human neonates contains a consistent contingent of CD138+ plasma cells, producing all classes and subclasses of immunoglobulins with the exception of IgD. These antibody-secreting cells are part of a larger subset of B cells that share the expression of signature genes defining mouse B1 cells, yet lack the expression of complement receptors CD21 and CD35. Data from single-cell transcriptomic, clonal correspondence and in vitro differentiation assays support the notion of intrathymic CD138+ plasma cell differentiation, alongside other B cell subsets with distinctive molecular phenotypes. Lastly, neonatal thymic plasma cells also include clones reactive to commensal and pathogenic bacteria that commonly infect children born with antibody deficiency. Thus, our findings point to the thymus as a source of innate humoral immunity in human neonates.

The predictive role of lymphocyte subsets and laboratory measurements in COVID-19 disease: a retrospective study.

AIM: The aim of this study was to investigate the predictive role of lymphocyte subsets and other laboratory measurements in patients with COVID-19. METHODS: Electronic medical records of adult patients with confirmed diagnosis of COVID-19 from the Shanghai Public Health Clinical Center were reviewed retrospectively to obtain relevant data. RESULTS: The mean age of patients was 40.98 ± 15.95 years, with 58% of the patients being males. The cutoff values at the intensive care unit (ICU) admission, mechanical ventilation, and mortality were CD4+ cells (267, 198, and 405), CD8+ cells (263, 203, and 182), and CD4+ /CD8+ cells (1.4, 1.8, and 1.4). The cutoffs below these values indicate the higher chances of disease progression. Higher CD4+ cell count led to lesser chances for ICU admission [odds ratio (OR) (95% confidence interval (CI): 0.994 (0.991, 0.997); p = 0.0002] and mortality [OR (95% CI): 0.988 (0.979, 0.99); p = 0.001], higher CD8+ count was an independent risk factor for ICU admission. T-cell count positively correlated with total lymphocyte count and platelets, while negatively correlated with D-dimer and lactate dehydrogenase (LDH). Among patients with non-severe COVID-19, median CD8+ T cell, CD4+ T cell, total lymphocyte count, and platelets were 570, 362, 1.45, and 211, respectively, while median values decreased to 149, 106, 0.64, and 172, respectively, in patients with severe COVID-19. CONCLUSION: Lower T lymphocyte subsets were significantly associated with higher admission to ICU, mechanical ventilation, and mortality among patients with COVID-19. A cutoff value of ICU admission, mechanical ventilation, and mortality below CD4+ cells (267, 198, and 405), CD8+ cells (263, 203, 182), and CD4+/CD8+ cells (1.4, 1.8, 1.4) may help identify patients at high risk of disease progression. The continuous evaluation of laboratory indices may help with dismal prognosis and prompt intervention to improve outcomes.

Evaluation and validation of a novel 10-color flow cytometer.

BACKGROUND: Flow cytometry is a powerful technique that provides information regarding cell properties. In this study, we evaluated the analytical performance of a new flow cytometer, the 10-color BD FACSLyricTM , which could help doctors obtain reliable test results prior to clinical research. METHODS: We used SpheroTM Rainbow Calibration Particles and the SpheroTM Nano Fluorescent Particle Size Standard Kit to validate the fluorescence sensitivity and linearity. The Beckman Coulter IMMUNO-TROL Cell was used as the quality control to evaluate the accuracy and reproducibility of surface markers detected by the flow cytometer. Furthermore, BD Calibrate APC Beads and CS&T Research Beads were applied to calculate the carry-over contamination rate and assess the instrument stability. RESULTS: A linear regression equation between the molecules of equivalent soluble fluorochrome and fluorescence detection limit showed a good linear fit (R2  > 0.99). The minimum bead size detected by side scatter was 0.22 µm. The coefficient of variation percentage of each fluorescence channel was below 2%, and the carry-over contamination rate of the cytometer was under 0.2%. After running the BD FACSLyricTM cytometer continuously for 8 h, the median fluorescence index of particles remained close to that at the time of cytometer startup. CONCLUSIONS: The 10-color BD FACSLyricTM cytometer showed good performance in the evaluation performed in this study and may be trusted to provide accurate results for clinical research.

Infants Younger Than 90 Days Admitted for Late-Onset Sepsis Display a Reduced Abundance of Regulatory T Cells.

Objective: To provide epidemiological data of infants < 90 days of age with suspected late-onset sepsis (LOS) and evaluate distinct immunological specificities. We hypothesized that previously healthy infants < 3 months of age with sepsis have a yet undefined immunological predisposition; e.g. differences in lymphocyte subsets including regulatory T cells. Methods: We performed an exploratory, single center study between January 1st, 2019 and June 1st, 2021. Routine diagnostics included conventional culture (blood, cerebrospinal fluid, urine), PCR and inflammatory markers in infants < 90 days of age with suspected sepsis. We additionally analyzed lymphocyte subsets and CD4+ CD25+ forkhead box protein (FoxP3)+ Tregs at admission for sepsis workup as compared to age-matched controls. Results: A convenience sample cohort of n= 51 infants with sepsis workup was enrolled. Invasive bacterial infection (IBI) was diagnosed in 25 (49.0%) patients including two infants with a rhinovirus co-infection and viral infection in 14 (27.5%) neonates. No infectious cause was found in 12 cases. Infants with suspected LOS displayed a decreased abundance of CD4+ FoxP3+ T cells as compared to controls, which was most pronounced in the subgroup of infants with IBI. We also noticed elevated HLA-DR-positive CD3+ cells in infants with LOS and a higher CD4/CD8-ratio in infants with viral infection as compared to healthy controls. Infants with viral infections had a higher number of natural killer cells as compared to infants with IBI. Conclusion: Our exploratory data support the concept of a potential immaturity state and failed immune tolerance development for young infants with LOS. Future large-scale studies are needed to elucidate pre-sepsis conditions and to target the microbiome-immunity interplay as a potential risk pattern.

Granzyme A and CD160 expression delineates ILC1 with graded functions in the mouse liver.

Type 1 innate lymphoid cells (ILC1) are tissue-resident lymphocytes that provide early protection against bacterial and viral infections. Discrete transcriptional states of ILC1 have been identified in homeostatic and pathological contexts. However, whether these states delineate ILC1 with different functional properties is not completely understood. Here, we show that liver ILC1 are heterogeneous for the expression of distinct effector molecules and surface receptors, including granzyme A (GzmA) and CD160, in mice. ILC1 expressing high levels of GzmA are enriched in the liver of adult mice, and represent the main hepatic ILC1 population at birth. However, the heterogeneity of GzmA and CD160 expression in hepatic ILC1 begins perinatally and increases with age. GzmA+ ILC1 differ from NK cells for the limited homeostatic requirements of JAK/STAT signals and the transcription factor Nfil3. Moreover, by employing Rorc(γt)-fate map (fm) reporter mice, we established that ILC3-ILC1 plasticity contributes to delineate the heterogeneity of liver ILC1, with RORγt-fm+ cells skewed toward a GzmA- CD160+ phenotype. Finally, we showed that ILC1 defined by the expression of GzmA and CD160 are characterized by graded cytotoxic potential and ability to produce IFN-γ. In conclusion, our findings help deconvoluting ILC1 heterogeneity and provide evidence for functional diversification of liver ILC1.

Analysis of Lymphocyte Subpopulations and Cytokines in COVID-19-Associated Pneumonia and Community-Acquired Pneumonia.

BACKGROUND: The 2019 novel coronavirus SARS-CoV-2 caused large outbreaks of COVID-19 worldwide. COVID-19 resembles community-acquired pneumonia (CAP). Our aim was to identify lymphocyte subpopulations to distinguish between COVID-19 and CAP. METHODS: We compared the peripheral blood lymphocytes and their subsets in 296 patients with COVID-19 and 130 patients with CAP. Parameters for independent prediction of COVID-19 were calculated by logistic regression. RESULTS: The main lymphocyte subpopulations (CD3+CD4+, CD16+CD56+, and CD4+/CD8+ ratio) and cytokines (TNF-α and IFN-γ) of COVID-19 patients were significantly different from that of CAP patients. CD16+CD56+%, CD4+/CD8+ratio, CD19+, and CD3+CD4+ were identified as predictors of COVID-19 diagnosis by logistic regression. In addition, the CD3+CD4+counts, CD3+CD8+ counts, andTNF-α are independent predictors of disease severity in patients. CONCLUSIONS: Lymphopenia is an important part of SARS-CoV-2 infection, and lymphocyte subsets and cytokines may be useful to predict the severity and clinical outcomes of the disease.

Serum free culture for the expansion and study of type 2 innate lymphoid cells.

Type 2 innate lymphoid cells (ILC2s) were discovered approximately ten years ago and their clinical relevance is gaining greater importance. However, their successful isolation from mammalian tissues and in vitro culture and expansion continues to pose challenges. This is partly due to their scarcity compared to other leukocyte populations, but also because our current knowledge of ILC2 biology is incomplete. This study is focused on ST2+ IL-25Rlo lung resident ILC2s and demonstrate for the first time a methodology allowing mouse type 2 innate lymphoid cells to be cultured, and their numbers expanded in serum-free medium supplemented with Interleukins IL-33, IL-2, IL-7 and TSLP. The procedures described methods to isolate ILC2s and support their growth for up to a week while maintaining their phenotype. During this time, they significantly expand from low to high cell concentrations. Furthermore, for the first time, sub-cultures of primary ILC2 purifications in larger 24- and 6-well plates were undertaken in order to compare their growth in other media. In culture, ILC2s had doubling times of 21 h, a growth rate of 0.032 h-1 and could be sub-cultured in early or late phases of exponential growth. These studies form the basis for expanding ILC2 populations that will facilitate the study and potential applications of these rare cells under defined, serum-free conditions.

Lymphocyte subset analysis to evaluate the prognosis of HIV-negative patients with pneumocystis pneumonia.

OBJECTIVES: We analysed the peripheral blood lymphocyte subsets of human immunodeficiency virus (HIV)-negative patients infected with pneumocystis pneumonia (PCP) to determine the relationships between the levels of different types of lymphocytes and the prognosis of patients. METHODS: We retrospectively reviewed HIV-negative patients with PCP diagnosed in our department. All the eligible patients underwent lymphocyte subset analysis on admission. RESULTS: A total of 88 HIV-negative PCP patients were enrolled in the study. In univariate analyses, low CD4+ T cell count, low CD8+ T cell count, and low natural killer cell (NK cell) count were associated with higher in-hospital mortality. CD8+ T cell count ≤300/µL was found to be an independent risk factor for poor prognosis in multivariate logistical regression analysis (p = 0.015, OR = 11.526, 95% CI = 1.597-83.158). Although low CD4+ T cell and NK cell counts were not independent risk factors, the mortality rates of PCP patients decreased as the CD4+ T cell and NK cell counts increased. CONCLUSION: The immune process of Pneumocystis jirovecii infection is complex but important. We propose that lymphocyte subsets could give clinicians a better understanding of patient immune status, helping with the early identification of potentially lethal infections and treatment decision making, such as adjusting the immunosuppressive regimen and choosing an appropriate patient monitoring level.

Natural Killer Cells Generated From Human Induced Pluripotent Stem Cells Mature to CD56brightCD16+NKp80+/-In-Vitro and Express KIR2DL2/DL3 and KIR3DL1.

The differentiation of human induced pluripotent stem cells (hiPSCs) into T and natural killer (NK) lymphocytes opens novel possibilities for developmental studies of immune cells and in-vitro generation of cell therapy products. In particular, iPSC-derived NK cells gained interest in adoptive anti-cancer immunotherapies, since they enable generation of homogenous populations of NK cells with and without genetic engineering that can be grown at clinical scale. However, the phenotype of in-vitro generated NK cells is not well characterized. NK cells derive in the bone marrow and mature in secondary lymphoid tissues through distinct stages from CD56brightCD16- to CD56dimCD16+ NK cells that represents the most abandoned population in peripheral blood. In this study, we efficiently generated CD56+CD16+CD3- NK lymphocytes from hiPSC and characterized NK-cell development by surface expression of NK-lineage markers. Hematopoietic priming of hiPSC resulted in 31.9% to 57.4% CD34+CD45+ hematopoietic progenitor cells (HPC) that did not require enrichment for NK lymphocyte propagation. HPC were further differentiated into NK cells on OP9-DL1 feeder cells resulting in high purity of CD56brightCD16- and CD56brightCD16+ NK cells. The output of generated NK cells increased up to 40% when OP9-DL1 feeder cells were inactivated with mitomycine C. CD7 expression could be detected from the first week of differentiation indicating priming towards the lymphoid lineage. CD56brightCD16-/+ NK cells expressed high levels of DNAM-1, CD69, natural killer cell receptors NKG2A and NKG2D, and natural cytotoxicity receptors NKp46, NKp44, NKp30. Expression of NKp80 on 40% of NK cells, and a perforin+ and granzyme B+ phenotype confirmed differentiation up to stage 4b. Killer cell immunoglobulin-like receptor KIR2DL2/DL3 and KIR3DL1 were found on up to 3 and 10% of mature NK cells, respectively. NK cells were functional in terms of cytotoxicity, degranulation and antibody-dependent cell-mediated cytotoxicity.

Inflammatory status might direct ILC and NK cells to IL-17 expressing ILC3 and NK subsets in Behcet's disease.

Innate lymphoid cells (ILCs) are lymphoid cells that have important effector and regulatory functions in innate immunity and tissue remodeling. Uncontrolled activation and proliferation of ILCs can contribute to inflammatory autoimmune diseases. Behcet's disease (BD) is a complex systemic inflammatory disorder of unknown etiology. It has been shown that natural killer (NK) cells may play an immunoregulatory role in BD, however the role of ILCs is unknown. In this study, the levels and functions of ILCs and NK cell subsets in BD patients were investigated. Cell surface and cytotoxic granules (perforin and granzyme) expression of NK cells and ILCs were evaluated and labeled according to whole blood lysing protocol in peripheral blood samples obtained from the patients and healthy subjects. Cytokine levels of NK cells were investigated in stimulated peripheral blood mononuclear cells. All data were analyzed by flow cytometry. Total ILC and ILC3+ cells were increased in active BD patients compared to inactive BD patients and healthy subjects. There was no significant difference between the patients and healthy subjects regarding NK cell surface and intracellular molecule expression. Although, an increase in IFN-γ and IL-17, and a decrease in IL-4 levels were observed in CD56dim NK cell subset of BD patients. Recent studies showed increased neutrophilic infiltration and IL-17 secreting Th17 cells in BD patients. It is known that ILC3+cells are similar to Th17 subset regarding their cytokine profile and transcription factor expression patterns. Results of current study may suggest that inflammatory microenvironment in BD patients might direct ILC cells to differentiate into ILC3+ subset, and IL-17 released by NK cells might have a role in neutrophilic infiltration.

22q11.2 deletion syndrome: 20 years of experience from two pediatric immunology units and review of clues for diagnosis and disease management.

INTRODUCTION AND OBJECTIVES: The purpose of this study was to evaluate patients diagnosed with 22q11.2 deletion syndrome and determine the clues directing to diagnosis and evaluation of immunological findings for excellent management of the disease. MATERIAL AND METHODS: Thirty-three pediatric patients with 22q11.2 deletion syndrome diagnosed between 1998 and 2019 at Pediatric Immunology Division of Ege University Faculty of Medicine and SBU Izmir Dr Behcet Uz Children's Education and Research Hospital were evaluated. RESULTS: This study includes the largest case series reported from Turkey. Congenital cardiac anomalies were the most common pathology associated with the syndrome (90.9%). Hypocalcemic symptoms were observed in 13 patients (40%). Twenty-two of the 33 (66.6%) patients were diagnosed before two years of age. Autoimmune diseases, dysmorphic facial findings, recurrent infections, growth retardation, and speech impairment were other clues for diagnosis in older patients. Clinical spectrum and immunological abnormalities of this syndrome are quite variable. All T-cell subset counts were less than 5th percentile below median by age in one patient (3%) and 10 patients had normal all T-cell subset counts (30.3%). Overall, 69.6% of the patients had normal IgG, IgA, and IgM levels and two patients had panhypogammaglobulinemia. Recurrent infections were revealed in 75.7% of the patients during follow-up. CONCLUSIONS: Presence of cardiac anomaly is more helpful in the diagnosis, especially under two years of age. Patients with immunologically high or standard risk did not show any difference in terms of numbers and severity of infections and autoimmunity.

Flow Cytometric Characterization of Murine B Cell Development.

Extensive studies have characterized the development and differentiation of murine B cells in secondary lymphoid organs. Antibodies secreted by B cells have been isolated and developed into well-established therapeutics. Validation of murine B cell development, in the context of autoimmune prone mice, or in mice with modified immune systems, is a crucial component of developing or testing therapeutic agents in mice and is an appropriate use of flow cytometry. Well established B cell flow cytometric parameters can be used to evaluate B cell development in the murine peritoneum, bone marrow, and spleen, but a number of best practices must be adhered to. In addition, flow cytometric analysis of B cell compartments should also complement additional readouts of B cell development. Data generated using this technique can further our understanding of wild type, autoimmune prone mouse models as well as humanized mice that can be used to generate antibody or antibody-like molecules as therapeutics.

The effect of erythrocyte lysing reagents on enumeration of leukocyte subpopulations compared with a no-lyse-no-wash protocol.

INTRODUCTION: Standard protocols in flow cytometry (FCM) require lysis of erythrocytes, which may induce an unwanted loss of leukocytes as bystander effect. METHODS: In the present study, we investigated the influence of 6 laboratory protocols using 4 different lysing reagents, FACS® Lysing Solution (FacsL), QUICKLYSIS® (QuickL), IOTest® 3 Lysing Solution (NH4Cl), VersaLyse® (VersaL), and VersaLyse® with added fixative (VersaFix) on the relative quantity of leukocyte subsets identified by CD3, CD4, CD8, CD19, CD14, CD16, CD56, and CD45, applying a no-lyse-no-wash (NoL) protocol as reference. In addition, we compared the efficiency of red blood cell (RBC) lysis. RESULTS: Peripheral blood samples from 52 individuals were analyzed. NoL was suitable as reference method, but led to less clear-cut gating of lymphocyte and monocyte populations due to a wider distribution of light scatter. Best completeness of RBC lysis with remaining erythrocytes below 10% was achieved using NH4Cl and VersaL. We observed a loss of 11% of monocytes after QuickL. Lymphocyte counts were 19% lower after FacsL. Cell subsets within the lymphocyte compartment were rather similar between the different methods with the exception of lower B-cell counts (-8%) and higher NK-cell counts (+11%) after FacsL. NH4Cl and VersaL were in good accordance with the NoL method and also with the mean values of all methods. CONCLUSION: Our data show that the lysing reagents tested lead to specific deviations in the quantitation of leukocyte subsets and show different efficiency of erythrocyte lysis.

Clinical significance of cellular immunity function and inflammatory factors assays in alveolar lavage fluid for severe COVID-19 pneumonia.

In this study, we aimed to investigate the changes of lymphocyte subsets (CD3+ , CD4+ , CD8+ ) and inflammatory factors (interleukin-6 [IL-6], hypersensitive C-reactive protein [HS-CRP], and procalcitonin [PCT]) of alveolar lavage fluid in patients with severe corona virus-2019 (COVID-19) pneumonia and their clinical impact on the assessment of disease severity and prognosis. Twenty-four patients with severe COVID-19 pneumonia were admitted to the intensive care unit (ICU) of the Ezhou Central Hospital from February 1 to March 22, 2020. According to the 28-day prognosis, they were assigned to a death group and a survival group. On the 3rd day of ICU admission, peripheral blood and alveolar lavage fluid were collected for examination of lymphocyte subsets and inflammatory factors by flow cytometry and immunoturbidimetry, respectively. The CD3+ , CD4+ , and CD8+ cell counts in alveolar lavage fluid and serum were significantly higher in the survival group than those of the death group (p < .05). The levels of IL-6, HS-CRP, and PCT in the alveolar lavage fluid and serum of the death group were statistically higher than those of the survival group (p < .05); The CD3+ , CD4+ cell count, and IL-6 level were negatively correlated with Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation II scores, respectively (p < .05). The CD4+ cell and SOFA score have a regression relationship for the prognosis of COVID-19 severe patients. The CD3+ , CD4+ , CD8+ cells, and IL-6 levels are valuable in determining the prognosis of severe COVID-19 pneumonia and are strongly correlated with the severity of the disease; the CD4+ cell is an independent risk factor affecting the prognosis of COVID-19 pneumonia.

Low Levels of Granulocytic Myeloid-Derived Suppressor Cells May Be a Good Marker of Survival in the Follow-Up of Patients With Severe COVID-19.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a disease (coronavirus disease 2019, COVID-19) that may develop into a systemic disease with immunosuppression and death in its severe form. Myeloid-derived suppressive cells (MDSCs) are inhibitory cells that contribute to immunosuppression in patients with cancer and infection. Increased levels of MDSCs have been found in COVID-19 patients, although their role in the pathogenesis of severe COVID-19 has not been clarified. For this reason, we raised the question whether MDSCs could be useful in the follow-up of patients with severe COVID-19 in the intensive care unit (ICU). Thus, we monitored the immunological cells, including MDSCs, in 80 patients admitted into the ICU. After 1, 2, and 3 weeks, we examined for a possible association with mortality (40 patients). Although the basal levels of circulating MDSCs did not discriminate between the two groups of patients, the last measurement before the endpoint (death or ICU discharge) showed that patients discharged alive from the ICU had lower levels of granulocytic MDSCs (G-MDSCs), higher levels of activated lymphocytes, and lower levels of exhausted lymphocytes compared with patients who had a bad evolution (death). In conclusion, a steady increase of G-MDSCs during the follow-up of patients with severe COVID-19 was found in those who eventually died.

Salbutamol combined with budesonide in treatment of pediatric bronchial asthma and its effect on eosinophils.

BACKGROUND: The aim of this study was to investigate and discuss the salbutamol combined with budesonide in treatment of pediatric bronchial asthma (BA) and its effect on eosinophils (EOS). METHODS: Ninety-eight BA children admitted and treated in our hospital from July 2016 to June 2017 were collected and divided into control group (N.=49) and observation group (N.=49) according to random number table. The children in control group were treated with budesonide and those in observation group were treated with salbutamol combined with budesonide. The clinical efficacy, pulmonary functions and levels of T-lymphocyte subsets (including cluster of differentiation 3 (CD3)+, CD4+, CD8+ and CD4+/CD8+) in the immune system between two groups were compared after the treatment; the levels of eosinophil cationic protein (ECP) and eotaxin in the children were compared before the treatment and at 1, 4 and 8 weeks after the treatment; the changes in EOS counts in blood and induced sputum of the children before and after the treatment were compared, and the EOS apoptosis rate was compared at 1, 4 and 8 weeks after the treatment. RESULTS: The effective rate of treatment in observation group was significantly higher than that in control group (P<0.05). After the treatment, the indexes of pulmonary function in observation group were obviously better than those in control group (P<0.05). Compared with those in control group, the levels of CD3+, CD4+ and CD4+/CD8+ of the children in observation group were elevated remarkably, while the CD8+ level was lowered (P<0.05). The levels of ECP and eotaxin in the two groups were decreased after the treatment compared with those before the treatment, and the levels in observation group were superior to those in control group (P<0.05). After the treatment, the EOS counts of both groups of children were lower than those before the treatment, and the decrease in observation group was more notable than that in control group. At 1, 4 and 8 weeks after the treatment, the EOS apoptosis rate in observation group was obviously higher than that in control group (P<0.05). CONCLUSIONS: The treatment of salbutamol combined with budesonide for pediatric BA has significant therapeutic effects; it can restore the pulmonary functions rapidly and improve the immunity of the lung, reduce the levels of eotaxin, ECP and EOS of the child patients and promote EOS apoptosis.

Artemisinin attenuates IgM xenoantibody production via inhibition of T cell-independent marginal zone B cell proliferation.

Artemisinin (ART) has been shown to suppress B cell activation and plasma cell formation. However, its effect on splenic marginal zone (MZ) B cells is unknown. Splenic MZ B cells play a critical role in rapidly induced Ab production against blood-borne foreign Ags. Dysfunction of MZ B cells, due to inhibition of its proliferation or displacement of its homing, results in an attenuated adaptive humoral response. Here, we investigate the effect of ART on splenic MZ B (CD19+ CD21high CD23low ) and B10 (CD19+ CD1dhigh CD5+ ) B cells to explore the mechanisms of ART-induced immunosuppression in T cell-deficient nude mice challenged with hamster xenoantigens. In this study, we demonstrate that ART decreases T cell-independent xenogeneic IgM Ab production and, this is associated with a strong suppression of MZ B cell proliferation and a relative increase of CD21low CD23+ follicular and B10 B cells. In addition, this suppression impairs IL-10 production. Taken together, our data indicate that ART suppresses B cell immune responses through a distinctive effect on splenic MZ B and other B cells. This represents a new mechanism of ART-induced immunosuppression.

Comparison of three methods to stabilize bronchoalveolar lavage cells for flowcytometric analysis.

BACKGROUND: Flowcytometric analysis of lymphocytes and their subpopulations in bronchoalveolar lavages (BAL) can support the diagnosis of interstitial lung diseases. This analysis should be done within 4 hr after lavage due to rapid cell deterioration. We tested three methods in order to stabilize for at least 28 days the BAL cell populations to allow delayed flowcytometric analysis in order to facilitate external quality assurance (EQA). METHODS: We compared an in-house, dual-step stabilization method for BAL cells with results of two different commercial available stabilization reagents: TransFix® and Streck Cell Preservative™. All three methods were compared with native BAL cells as reference. BAL samples from six patients were tested on six occasions following stabilization from 1 to 28 days by flow cytometry. RESULTS: Following stabilization and storage at 4°C, BAL cell suspensions had stable light scatter patterns and lymphocyte subsets. As expected, rapid deterioration of cells was seen with native BAL cells. The stabilized lavages showed more stable counts of WBC and lymphocyte populations with only minor differences found between the three methods. CONCLUSIONS: If analysis of the BAL cells is performed more than 24 hr after the lavage, stabilized BAL cells are superior to native cells. The in-house method can be used for EQA purposes with stability for at least 28 days. The TransFix and Streck methods might be useful for postponed diagnostic analysis of lavage cells but did not meet our 28 days criterion defined needed for EQA purposes.