Systemic immunological profile of children with B-cell acute lymphoblastic leukemia: performance of cell populations and soluble mediators as serum biomarkers

Background

Children with B-cell acute lymphoblastic leukemia (B-ALL) have an immune imbalance that is marked by remodeling of the hematopoietic compartment, with effects on peripheral blood (PB). Although the bone marrow (BM) is the main maintenance site of malignancy, the frequency with which immune cells and molecules can be monitored is limited, thus the identification of biomarkers in PB becomes an alternative for monitoring the evolution of the disease.

Methods

Here, we characterize the systemic immunological profile in children undergoing treatment for B-ALL, and evaluate the performance of cell populations, chemokines and cytokines as potential biomarkers during clinical follow-up. For this purpose, PB samples from 20 patients with B-ALL were collected on diagnosis (D0) and during induction therapy (days 8, 15 and 35). In addition, samples from 28 children were used as a control group (CG). The cellular profile (NK and NKT-cells, Treg, CD3+ T, CD4+ T and CD8+ T cells) and soluble immunological mediators (CXCL8, CCL2, CXCL9, CCL5, CXCL10, IL-6, TNF, IFN-γ, IL-17A, IL- 4, IL-10 and IL-2) were evaluated via flow cytometry immunophenotyping and cytometric bead array assay.

Results

On D0, B-ALL patients showed reduction in the frequency of cell populations, except for CD4+ T and CD8+ T cells, which together with CCL2, CXCL9, CXCL10, IL-6 and IL-10 were elevated in relation to the patients of the CG. On D8 and D15, the patients presented a transition in the immunological profile. While, on D35, they already presented an opposite profile to D0, with an increase in NKT, CD3+ T, CD4+ T and Treg cells, along with CCL5, and a decrease in the levels of CXCL9, CXCL10 and IL-10, thus demonstrating that B-ALL patients present a complex and dynamic immune network during induction therapy. Furthermore, we identified that many immunological mediators could be used to classify the therapeutic response based on currently used parameters.

Conclusion

Finally, it is noted that the systemic immunological profile after remission induction still differs significantly when compared to the GC and that multiple immunological mediators performed well as serum biomarkers.

Bone Marrow Soluble Immunological Mediators as Clinical Prognosis Biomarkers in B-Cell Acute Lymphoblastic Leukemia Patients Undergoing Induction Therapy

Different factors are used as predictors of unfavorable clinical outcomes in B-Cell Acute Lymphoblastic Leukemia (B-ALL) patients. However, new prognostic markers are needed in order to allow treatment to be more accurate, providing better results and an improved quality of life. In the present study, we have characterized the profile of bone marrow soluble mediators as possible biomarkers for risk group stratification and minimal residual disease (MRD) detection during induction therapy. The study featured 47 newly-diagnosed B-cell acute lymphoblastic leukemia (B-ALL) patients that were categorized into subgroups during induction therapy according to risk stratification at day 15 [Low Risk (LR), Low Risk increasing to High Risk (LR→HR) and High Risk (HR)] and the MRD detection on day 35 (MRD^(-) and MRD⁽⁺⁾). Soluble immunological mediators (CXCL8, CCL2, CXCL9, CCL5, CXCL10, IL-1β, IL-6, TNF, IFN-γ, IL-17A, IL-4, IL-5, IL-10 and IL-2) were quantified by cytometric bead array and ELISA. Our findings demonstrated that increased levels of CCL5, IFN-γ and IL-2 at baseline appeared as putative candidates of good prognosis in LR and MRD^(-) subgroups, while CCL2 was identified as a consistent late biomarker associated with poor prognosis, which was observed on D35 in HR and MRD⁽⁺⁾ subgroups. Furthermore, apparently controversial data regarding IL-17A and TNF did not allow the definition of these molecules as either positive or negative biomarkers. These results contribute to the search for novel prognostic indicators, and indicate the potential of bone marrow soluble mediators in prognosis and follow-up of B-ALL patients during induction therapy.

Ascaris lumbricoides coinfection reduces tissue damage by decreasing IL-6 levels without altering clinical evolution of pulmonary tuberculosis or Th1/Th2/Th17 cytokine profile

INTRODUCTION

Immunological control of Mycobacterium tuberculosis infection is dependent on the cellular immune response, mediated predominantly by Th1 type CD4+ T cells. Polarization of the immune response to Th2 can inhibit the host immune protection against pathogens. Patients with tuberculosis coinfected with helminths demonstrate more severe pulmonary symptoms, a deficiency in the immune response against tuberculosis, and an impaired response to anti-tuberculosis therapy.

METHODS

We evaluated the cellular immune response and the impact of the presence of Ascaris lumbricoides on the immune and clinical response in pulmonary tuberculosis patients. Ninety-one individuals were included in the study: 38 tuberculosis patients, 11 tuberculosis patients coinfected with Ascaris lumbricoides and other helminths, 10 Ascaris lumbricoides patients, and 34 non-infected control individuals. Clinical evolution of pulmonary tuberculosis was studied on 0, 30, 60, and 90 days post-diagnosis of Mycobacterium tuberculosis and Ascaris lumbricoides. Furthermore, immune cells and plasma cytokine profiles were examined in mono/coinfection by Mycobacterium tuberculosis and Ascaris lumbricoides using flow cytometry.

RESULTS

There were no statistical differences in any of the evaluated parameters and the results indicated that Ascaris lumbricoides infection does not lead to significant clinical repercussions in the presentation and evolution of pulmonary tuberculosis.

CONCLUSIONS

The association with Ascaris lumbricoides did not influence the Th1, Th2, and Th17 type responses, or the proportions of T lymphocyte subpopulations. However, higher serum levels of IL-6 in tuberculosis patients may explain the pulmonary parenchymal damage.

The effects of brief physical conditioning on immune cells and cytokines in elderly individuals in Manaus, Amazonas

Abstract Introduction: Aging is understood as the sum of all biological, psychological and social changes that occur over the years. Associated with aging we list up the changes of morphological and functional order of the immune system: Immunosenescence. Objective This study's objective was to characterize the effect of a brief exercise program on the profile of cytokines and peripheral blood mononuclear cells of elderly individuals in Manaus, AM, Brazil. Materials and methods: Twelve subjects aged 66.8 (± 3.7) years old on average engaged in three weekly sessions of exercises for 16 weeks and, seven subjects aged 66.1 (± 6.7) years on average, who practiced only recreational activities, composed the control group. Serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α and INF-γ were measured using the CBA technique (cytometric Bead Array) and the count of subpopulations of lymphocytes - B, B1, T/CD4, T/CD8, Treg, NK and NKT - was performed using flow cytometry. Results: The relative number of B lymphocytes, T/CD4+ and NKT (CD3+/CD16 +/CD56+) increased significantly (p <0.05) after physical activity, compared to the pre-exercise phase and the control group. In another analysis, each individual in the test group was classified either as major or minor producer of each cytokine; i.e., their values were above or below the cut-off point defined by the median of all measurements of that cytokine. Patterns of cytokine production were observed in the post-exercise group, which allowed defining sets ("signatures") of cytokines that were associated with the practice of short-term physical exercises. Conclusion: Our work showed that exercise induces changes in the count of immune cells, which allows us to infer that it can be used as an alternative to reverse or mitigate the implications of immunosenescence.

Liver and blood cytokine microenvironment in HCV patients is associated to liver fibrosis score: a proinflammatory cytokine ensemble orchestrated by TNF and tuned by IL-10

BACKGROUND

In this study, we have evaluated the immunological status of hepatitis C virus (HCV)-infected patients aiming at identifying putative biomarkers associated with distinct degrees of liver fibrosis. Peripheral blood and tissue T-cells as well as cytokine levels were quantified by flow cytometry.

RESULTS

Data analysis demonstrated higher frequency of circulating CD8(+) T-cells and Tregs along with a mixed proinflammatory/IL-10-modulated cytokine pattern in HCV patients. Patients with severe liver fibrosis presented lower frequency of circulating CD8(+) T-cells, higher levels of proinflammatory cytokines, but lower levels of IL-10, in addition to the higher viral load. Despite the lower frequency of intrahepatic T-cells and scarce frequency of Tregs, patients with severe liver fibrosis showed higher levels of proinflammatory cytokines (TNF and IFN-γ). The tissue proinflammatory cytokine pattern supported further studies of serum cytokines as relevant biomarkers associated with different liver fibrosis scores. Serum cytokine signature showed that mild liver fibrosis is associated with higher IL-10 serum levels as compared to severe liver disease. There was a clear positive connection of IL-10 with the TNF node in patients with mild liver fibrosis, whereas there is an evident inverse correlation between IL-10 with all other cytokine nodes.

CONCLUSIONS

These results suggest the absence of modulatory events in patients with severe liver damage as opposed to mild fibrosis. Machine-learning data mining pointed out TNF and IL-10 as major attributes to differentiate HCV patients from non-infected individuals with highest performance. In conclusion, our findings demonstrated that HCV infection triggers a local and systemic cytokine ensemble orchestrated by TNF and tuned by IL-10 in such a manner that mirrors the liver fibrosis score, which highly suggests the relevance of these set of biomarkers for clinical investigations.

Combined impact of hepatitis C virus genotype 1 and interleukin-6 and tumor necrosis factor-α polymorphisms on serum levels of pro-inflammatory cytokines in Brazilian HCV-infected patients

We investigated the association between hepatitis C virus (HCV) genotypes and host cytokine gene polymorphisms and serum cytokine levels in patients with chronic hepatitis C. Serum IL-6, TNF-α, IL-2, IFN-γ, IL-4, IL-10, and IL-17A levels were measured in 67 HCV patients (68.2% genotype 1 [G1]) and 47 healthy controls. The HCV patients had higher IL-6, IL-2, IFN-γ, IL-10, and IL-17A levels than the controls. HCV G1 patients had higher IL-2 and IFN-γ levels than G2 patients. The -174IL6G>C, -308TNFαG>A, and -1082IL10A>G variants were similarly distributed in both groups. However, HCV patients with the -174IL6GC variant had higher IL-2 and IFN-γ levels than patients with the GG and CC variants. Additionally, HCV patients with the -308TNFαGG genotype had higher IL-17A levels than patients with the AG genotype, whereas patients with the -1082IL10GG variant had higher IL-6 levels than patients with the AA and AG variants. A significant proportion of HCV patients had high levels of both IL-2 and IFN-γ. The subgroup of HCV patients with the G1/IL6CG/TNFαGG association displayed the highest proportions of high producers of IL-2 and IFN-γ whereas the subgroup with the G1/TNFαGG profile showed high proportions of high producers of IL-6 and IL-17A. HCV patients with other HCV/cytokine genotype associations showed no particular cytokine profile. Our results suggest that HCV genotype G1 and IL-6 and TNF-α polymorphisms have a clinically relevant influence on serum pro-inflammatory cytokine profile (IL-2 and IFN-γ) in HCV patients.

Dual role of IL-12 in the therapeutic efficacy or failure during combined PEG-Interferon-α2A and ribavirin therapy in patients with chronic hepatitis C

Several efforts have been made to establish novel biomarkers with relevant predictive values to monitor HCV-infected patients under pegilated Interferon-α2A-(PEG-IFN-α2A)/ribavirin therapy. The aim of this study was to monitor the kinetics of HCV viral load, serum levels of pro-inflammatory/regulatory cytokines and leukocyte activation status before and after PEG-IFN-α2A/ribavirin therapy in 52 volunteers, including 12 chronic HCV patients and 40 controls. The HCV viral load, serum levels of cytokines (IL-8/IL-6/TNF-α/IL-12/IFN-γ/IL-4/IL-10) and the phenotype of peripheral blood leukocytes were evaluated before and after 4, 12 and 24 weeks following the PEG-IFN-α2A/ribavirin therapy. Our results demonstrated that sustained virological response-(SVR) is associated with early decrease in the viral load after 4 weeks of treatment. The presence of a modulated pro-inflammatory profile at baseline favors SVR, whereas a strong inflammatory response at baseline predisposes to therapeutic failure. Furthermore, a time-dependent increase on serum IL-12 levels in patients under treatment is critical to support the SVR, while the early predominance of IL-10 correlates to late virological relapse. On the other hand, a broad but unguided "cytokine storm" is observed in the non-responder HCV patients after 12 weeks of treatment. Corroborating these findings, monocyte/lymphocyte activation at baseline is associated with the non-responders to therapy whereas high CD8(+) T-cell numbers associate with SVR. All in all, these data suggest that the baseline pattern of serum pro-inflammatory/regulatory cytokines and the immunological activation status of chronic HCV patients undergoing PEG-IFN-α2A/ribavirin therapy are closely related with the therapeutic response.