ZIP8 expression in human proximal tubule cells, human urothelial cells transformed by Cd+2 and As+3 and in specimens of normal human urothelium and urothelial cancer

Background

ZIP8 functions endogenously as a Zn⁺²/HCO₃ ^- symporter that can also bring cadmium (Cd⁺²) into the cell. It has also been proposed that ZIP8 participates in Cd-induced testicular necrosis and renal disease. In this study real-time PCR, western analysis, immunostaining and fluorescent localization were used to define the expression of ZIP8 in human kidney, cultured human proximal tubule (HPT) cells, normal and malignant human urothelium and Cd⁺² and arsenite (As⁺³) transformed urothelial cells.

Results

It was shown that in the renal system both the non-glycosylated and glycosylated form of ZIP8 was expressed in the proximal tubule cells with localization of ZIP8 to the cytoplasm and cell membrane; findings in line with previous studies on ZIP8. The studies in the bladder were the first to show that ZIP8 was expressed in normal urothelium and that ZIP8 could be localized to the paranuclear region. Studies in the UROtsa cell line confirmed a paranuclear localization of ZIP8, however addition of growth medium to the cells increased the expression of the protein in the UROtsa cells. In archival human samples of the normal urothelium, the expression of ZIP8 was variable in intensity whereas in urothelial cancers ZIP8 was expressed in 13 of 14 samples, with one high grade invasive urothelial cancer showing no expression. The expression of ZIP8 was similar in the Cd⁺² and As⁺³ transformed UROtsa cell lines and their tumor transplants.

Conclusion

This is the first study which shows that ZIP8 is expressed in the normal urothelium and in bladder cancer. In addition the normal UROtsa cell line and its transformed counterparts show similar expression of ZIP8 compared to the normal urothelium and the urothelial cancers suggesting that the UROtsa cell line could serve as a model system to study the expression of ZIP8 in bladder disease.     

Tracheal Aspirate Levels of the Matricellular Protein SPARC Predict Development of Bronchopulmonary Dysplasia

Background

Isolation of tracheal aspirate mesenchymal stromal cells (MSCs) from premature infants has been associated with increased risk of bronchopulmonary dysplasia (BPD). MSCs show high levels of mRNAs encoding matricellular proteins, non-structural extracellular proteins that regulate cell-matrix interactions and participate in tissue remodeling. We hypothesized that lung matricellular protein expression predicts BPD development.

Methods

We collected tracheal aspirates and MSCs from mechanically-ventilated premature infants during the first week of life. Tracheal aspirate and MSC-conditioned media were analyzed for seven matricellular proteins including SPARC (for Secreted Protein, Acidic, Rich in Cysteine, also called osteonectin) and normalized to secretory component of IgA. A multiple logistic regression model was used to determine whether tracheal aspirate matricellular protein levels were independent predictors of BPD or death, controlling for gestational age (GA) and birth weight (BW).

Results

We collected aspirates from 89 babies (38 developed BPD, 16 died before 36 wks post-conceptual age). MSC-conditioned media showed no differences in matricellular protein abundance between cells from patients developing BPD and cells from patients who did not. However, SPARC levels were higher in tracheal aspirates from babies with an outcome of BPD or death (p<0.01). Further, our logistic model showed that tracheal aspirate SPARC (p<0.02) was an independent predictor of BPD/death. SPARC deposition was increased in the lungs of patients with BPD.

Conclusions

In mechanically-ventilated premature infants, tracheal aspirate SPARC levels predicted development of BPD or death. Further study is needed to determine the value of SPARC as a biomarker or therapeutic target in BPD.     

Arsenic, cadmium and neuron specific enolase (ENO2, γ-enolase) expression in breast cancer

Background

Neuron specific enolase (ENO2, γ-enolase) has been used as a biomarker to help identify neuroendocrine differentiation in breast cancer. The goal of the present study was to determine if ENO2 expression in the breast epithelial cell is influenced by the environmental pollutants, arsenite and cadmium. Acute and chronic exposure of MCF-10A cells to As⁺³ and Cd⁺² sufficient to allow colony formation in soft agar, was used to determine if ENO2 expression was altered by these pollutants.

Results

It was shown that both As⁺³ and Cd⁺² exposure caused significant increases in ENO2 expression under conditions of both acute and chronic exposure. In contrast, ENO1, the major glycolytic enolase in non-muscle and neuronal cells, was largely unaffected by exposure to either As⁺³ or Cd⁺². Localization studies showed that ENO2 in the MCF-10A cells transformed by As⁺³ or Cd⁺² had both a cytoplasmic and nuclear localization. In contrast, ENO1 was localized to the cytoplasm. ENO2 localized to the cytoplasm was found to co-localized with ENO1.

Conclusion

The results are the first to show that ENO2 expression in breast epithelial cells is induced by acute and chronic exposure to As⁺³ or Cd⁺². The findings also suggest a possible link between As⁺³ and Cd⁺² exposure and neuroendocrine differentiation in tumors. Overall, the results suggest that ENO2 might be developed as a biomarker indicating acute and/or chronic environmental exposure of the breast epithelial cell to As⁺³ and Cd⁺².     

SPARC Is a Key Regulator of Proliferation, Apoptosis and Invasion in Human Ovarian Cancer

Background

Secreted protein acidic and rich in cysteine (SPARC), a calcium-binding matricellular glycoprotein, is implicated in the progression of many cancers. In this study, we investigated the expression and function of SPARC in ovarian cancer.

Methods

cDNA microarray analysis was performed to compare gene expression profiles of the highly invasive and the low invasive subclones derived from the SKOV3 human ovarian cancer cell line. Immunohistochemistry (IHC) staining was performed to investigate SPARC expression in a total of 140 ovarian tissue specimens. In functional assays, effects of SPARC knockdown on the biological behavior of ovarian cancer cells were investigated. The mechanisms of SPARC in ovarian cancer proliferation, apoptosis and invasion were also researched.

Results

SPARC was overexpressed in the highly invasive subclone compared with the low invasive subclone. High SPARC expression was associated with high stage, low differentiation, lymph node metastasis and poor prognosis of ovarian cancer. Knockdown of SPARC expression significantly suppressed ovarian cancer cell proliferation, induced cell apoptosis and inhibited cell invasion and metastasis.

Conclusion

SPARC is overexpressed in highly invasive subclone and ovarian cancer tissues and plays an important role in ovarian cancer growth, apoptosis and metastasis.     

Decreased Frequency of Intestinal Regulatory CD5+ B Cells in Colonic Inflammation

Background

CD5⁺ B cells are a type of regulatory immune cells, though the involvement of this B cell subset in intestinal inflammation and immune regulation is not fully understood.

Methods

We examined the distribution of CD5⁺ B cells in various mouse organs. Expression levels of CD11b, IgM, and toll-like receptor (TLR)-4 and -9 in B cells were evaluated. In vitro, TLR-stimulated IL-10 production by colonic lamina propria (LP) CD5⁺ and CD5^- B cells was measured. In vivo, mice with acute or chronic dextran sulfate sodium (DSS)-induced colonic injury were examined, and the frequency of colonic LP CD5⁺ B cells in those was assessed by flow cytometry.

Results

The expression level of TLR9 was higher in colonic LP CD5⁺ B cells as compared to CD5^- B cells. Colonic LP CD5⁺ B cells produced greater amounts of IL-10 following stimulation with TLR ligands, especially TLR9, as compared with the LP CD5^- B cells. Acute intestinal inflammation transiently decreased the frequency of colonic LP CD5⁺ B cells, while chronic inflammation induced a persistent decrease in colonic LP CD5⁺ B cells and led to a CD5^- B cell-dominant condition.

Conclusion

A persistent altered mucosal B cell population caused by chronic gut inflammation may be involved in the pathogenesis of inflammatory bowel diseases.     

Prognostic Value of SPARC in Patients with Pancreatic Cancer: A Systematic Review and Meta-Analysis

Objective

There is a heated debate on whether the prognostic value of SPARC is favorable or unfavorable. Thus, we carried out a meta-analysis evaluating the relationship between SPARC expression and the prognosis of patients with pancreatic cancer.

Methods

We searched PubMed, EMBASE and Web of Science for relevant articles. The pooled hazard ratios (HRs) and corresponding 95%CI of overall survival (OS) were calculated to evaluate the prognostic value of SPARC expression in patients with pancreatic cancer. We also performed subgroup analyses.

Results

With 1623 patients pooled from 10 available studies, the incorporative HR showed an unfavorable prognosis of patients with pancreatic cancer in the multivariate analysis (HR = 1.55, 95%CI: 1.11–2.17, P = 0.01), but not in univariate analysis (HR = 1.41, 95%CI: 0.47–4.21, P = 0.54) and estimate (HR = 1.24, 95%CI: 0.72–2.13, P = 0.44). And this adverse impact could also be found in the subgroup analyses in multivariate analysis, especially in the stroma (HR = 1.53, 95%CI: 1.05–2.24, P = 0.03). However, the combined HR had the highly significant heterogeneity. No obvious publication bias was found.

Conclusions

SPARC might be an unfavorable indicator in patients with pancreatic cancer, especially in the stroma. More and further researches should be conducted to reveal the prognostic value of SPARC.     

Increased Protease-Activated Receptor-2 (PAR-2) Expression on CD14++CD16+ Peripheral Blood Monocytes of Patients with Severe Asthma

Background

Protease-Activated Receptor-2 (PAR-2), a G protein coupled receptor activated by serine proteases, is widely expressed in humans and is involved in inflammation. PAR-2 activation in the airways plays an important role in the development of allergic airway inflammation. PAR-2 expression is known to be upregulated in the epithelium of asthmatic subjects, but its expression on immune and inflammatory cells in patients with asthma has not been studied.

Methods

We recruited 12 severe and 24 mild/moderate asthmatics from the University of Alberta Hospital Asthma Clinics and collected baseline demographic information, medication use and parameters of asthma severity. PAR-2 expression on blood inflammatory cells was analyzed by flow cytometry.

Results

Subjects with severe asthma had higher PAR-2 expression on CD14⁺⁺CD16⁺ monocytes (intermediate monocytes) and also higher percentage of CD14⁺⁺CD16⁺PAR-2⁺ monocytes (intermediate monocytes expressing PAR-2) in blood compared to subjects with mild/moderate asthma. Receiver operating characteristics (ROC) curve analysis showed that the percent of CD14⁺⁺CD16⁺PAR-2⁺ in peripheral blood was able to discriminate between patients with severe and those with mild/moderate asthma with high sensitivity and specificity. In addition, among the whole populations, subjects with a history of asthma exacerbations over the last year had higher percent of CD14⁺⁺CD16⁺ PAR-2⁺ cells in peripheral blood compared to subjects without exacerbations.

Conclusions

PAR-2 expression is increased on CD14⁺⁺CD16⁺ monocytes in the peripheral blood of subjects with severe asthma and may be a biomarker of asthma severity. Our data suggest that PAR-2 -mediated activation of CD14⁺⁺CD16⁺ monocytes may play a role in the pathogenesis of severe asthma.     

Expansion of CD4+CD25+ helper T cells without regulatory function in smoking and COPD

Background

Regulatory T cells have been implicated in the pathogenesis of COPD by the increased expression of CD25 on helper T cells along with enhanced intracellular expression of FoxP3 and low/absent CD127 expression on the cell surface.

Method

Regulatory T cells were investigated in BALF from nine COPD subjects and compared to fourteen smokers with normal lung function and nine never-smokers.

Results

In smokers with normal lung function, the expression of CD25⁺CD4⁺ was increased, whereas the proportions of FoxP3⁺ and CD127⁺ were unchanged compared to never-smokers. Among CD4⁺ cells expressing high levels of CD25, the proportion of FoxP3⁺ cells was decreased and the percentage of CD127⁺ was increased in smokers with normal lung function. CD4⁺CD25⁺ cells with low/absent CD127 expression were increased in smokers with normal lung function, but not in COPD, when compared to never smokers.

Conclusion

The reduction of FoxP3 expression in BALF from smokers with normal lung function indicates that the increase in CD25 expression is not associated with the expansion of regulatory T cells. Instead, the high CD127 and low FoxP3 expressions implicate a predominantly non-regulatory CD25⁺ helper T-cell population in smokers and stable COPD. Therefore, we suggest a smoking-induced expansion of predominantly activated airway helper T cells that seem to persist after COPD development.     

Differential effects of SPARC and cationic SPARC peptides on DNA synthesis by endothelial cells and fibroblasts

SPARC (secreted protein, acidic and rich in cysteine), also known as osteonectin, is an extracellular Ca⁺²-glycoprotein that inhibits the incorporation of [³H]-and delays the onset of S-phase in synchronized cultures of bovine aortic endothelial (BAE) cells. This effect appears not to be dependent on the functional properties of SPARC associated with changes in cell shape or inhibition of cell spreading. In this study we investigate the conditions under which cell cycle modulation occurs in different types of cells. Human umbilical vein endothelial cells, a transformed fetal BAE cell line, and bovine capillary endothelial cells exhibited a sensitivity to SPARC and a cationic peptide from a non-Ca⁺²-region of SPARC (peptide 2.1, 0.2—0.8 mM) similar to that observed in BAE cells. In contrast, human foreskin fibroblasts and fetal bovine ligament fibroblasts exhibited an increase in the incorporation of [³H]-in the presence of 25 μM—0.2 mM peptide 2.1; inhibition was observed at concentrations in excess of 0.4 mM. This biphasic modulation could be further localized to a sequence of 10 amino acids comprising the N-terminal half of peptide 2.1. A synthetic peptide from another cationic region of SPARC (peptide 2.3) increased [³H]-incorporation by BAE cells and fibroblasts in a dose-dependent manner. In endothelial cells, a stimulation of 50% was observed at a concentration of 0.01 mM; fibroblasts required ～ 100-fold more peptide 2.3 for levels of stimulation comparable to those obtained in endothelial cells. The observation that SPARC and unique SPARC peptides can differentially influence the growth of fibroblasts and endothelial cells in a concentration-dependent manner suggests that SPARC might regulate proliferation of specific cells during wound repair and remodeling. © 1993 Wiley-Liss, Inc.     

Cigarette Smoke Disturbs the Survival of CD8+ Tc/Tregs Partially through Muscarinic Receptors-Dependent Mechanisms in Chronic Obstructive Pulmonary Disease

Background

CD8⁺ T cells (Cytotoxic T cells, Tc) are known to play a critical role in the pathogenesis of smoking related airway inflammation including chronic obstructive pulmonary disease (COPD). However, how cigarette smoke directly impacts systematic CD8⁺ T cell and regulatory T cell (Treg) subsets, especially by modulating muscarinic acetylcholine receptors (MRs), has yet to be well elucidated.

Methods

Circulating CD8⁺ Tc/Tregs in healthy nonsmokers (n = 15), healthy smokers (n = 15) and COPD patients (n = 18) were evaluated by flow cytometry after incubating with anti-CD3, anti-CD8, anti-CD25, anti-Foxp3 antibodies. Peripheral blood T cells (PBT cells) from healthy nonsmokers were cultured in the presence of cigarette smoke extract (CSE) alone or combined with MRs agonist/antagonist for 5 days. Proliferation and apoptosis were evaluated by flow cytometry using Ki-67/Annexin-V antibodies to measure the effects of CSE on the survival of CD8⁺ Tc/Tregs.

Results

While COPD patients have elevated circulating percentage of CD8⁺ T cells, healthy smokers have higher frequency of CD8⁺ Tregs. Elevated percentages of CD8⁺ T cells correlated inversely with declined FEV1 in COPD. CSE promoted the proliferation and inhibited the apoptosis of CD8⁺ T cells, while facilitated both the proliferation and apoptosis of CD8⁺ Tregs. Notably, the effects of CSE on CD8⁺ Tc/Tregs can be mostly simulated or attenuated by muscarine and atropine, the MR agonist and antagonist, respectively. However, neither muscarine nor atropine influenced the apoptosis of CD8⁺ Tregs.

Conclusion

The results imply that cigarette smoking likely facilitates a proinflammatory state in smokers, which is partially mediated by MR dysfunction. The MR antagonist may be a beneficial drug candidate for cigarette smoke-induced chronic airway inflammation.     

A Role for SPARC in the Moderation of Human Insulin Secretion

Aims/Hypothesis

We have previously shown the implication of the multifunctional protein SPARC (Secreted protein acidic and rich in cysteine)/osteonectin in insulin resistance but potential effects on beta-cell function have not been assessed. We therefore aimed to characterise the effect of SPARC on beta-cell function and features of diabetes.

Methods

We measured SPARC expression by qRT-PCR in human primary pancreatic islets, adipose tissue, liver and muscle. We then examined the relation of SPARC with glucose stimulated insulin secretion (GSIS) in primary human islets and the effect of SPARC overexpression on GSIS in beta cell lines.

Results

SPARC was expressed at measurable levels in human islets, adipose tissue, liver and skeletal muscle, and demonstrated reduced expression in primary islets from subjects with diabetes compared with controls (p< = 0.05). SPARC levels were positively correlated with GSIS in islets from control donors (p< = 0.01). Overexpression of SPARC in cultured beta-cells resulted in a 2.4-fold increase in insulin secretion in high glucose conditions (p< = 0.01).

Conclusions

Our data suggest that levels of SPARC are reduced in islets from donors with diabetes and that it has a role in insulin secretion, an effect which appears independent of SPARC’s modulation of obesity-induced insulin resistance in adipose tissue.     

PD-1, PD-L1 and PD-L2 Gene Expression on T-Cells and Natural Killer Cells Declines in Conjunction with a Reduction in PD-1 Protein during the Intensive Phase of Tuberculosis Treatment

Background

The PD-1 axis is a cell intrinsic immunoregulatory pathway that mediates T cell exhaustion in chronic infection particularly in some viral infections. We hypothesized that PD-1, PD-L1 and PD-L2 would be highly expressed in untreated tuberculosis patients compared to controls due to their chronic infection and would decrease with successful TB treatment.

Materials and Methods

Untreated tuberculosis patients (n = 26) were recruited at diagnosis and followed up during treatment. Household contacts (n = 24) were recruited to establish baseline differences. Blood gene expression ex vivo was investigated using qRT-PCR. Flow cytometry was performed to establish protein expression patterns.

Results

PD-L1 gene expression was found to be elevated in active TB disease; however, this was not observed for PD-1 or PD-L2. The intensive phase of TB treatment was associated with a significant decline in PD-1, PD-L1 and PD-L2 gene expression. PD-1 protein expression on the surface of NK cells, CD8⁺ and CD4⁺ T cells was similar in patients with active TB disease compared to controls but declined with successful TB treatment, with the greatest decline occurring on the NK cells followed by CD8⁺ T cells and then CD4⁺ T cells. Granzyme B/PD-1 co-expression declined with successful intensive phase treatment.

Conclusion

Modulation of PD-1/PD-L1 pathway through TB treatment indicates changes in the peripheral T cell response caused by live Mycobacterium tuberculosis (Mtb) followed by the response to dead bacilli, antigen-release and immuno-pathology resolution. The PD-1 axis could be a host drug target for immunomodulatory treatments in the future.     

IL-15 Superagonist Expands mCD8+ T,NK and NKT Cells after Burn Injury but Fails to Improve Outcome during Burn Wound Infection

Background

Severely burned patients are highly susceptible to opportunistic infections and sepsis, owing to the loss of the protective skin barrier and immunological dysfunction. Interleukin-15 (IL-15) belongs to the IL-2 family of common gamma chain cytokines and stimulates the proliferation and activation of T (specifically memory CD8), NK and NKT cells. It has been shown to preserve T cell function and improve survival during cecal ligation and puncture (CLP)-induced sepsis in mice. However, the therapeutic efficacy of IL-15 or IL-15 superagonist (SA) during infection after burn injury has not been evaluated. Moreover, very few, if any, studies have examined, in detail, the effect of burn injury and infection on the adaptive immune system. Thus, we examined the effect of burn and sepsis on adaptive immune cell populations and the effect of IL-15 SA treatment on the host response to infection.

Methods

Mice were subjected to a 35% total body surface area burn, followed by wound infection with Pseudomonas aeruginosa. In some experiments, IL-15 SA was administered after burn injury, but before infection. Leukocytes in spleen, liver and peritoneal cavity were characterized using flow cytometry. Bacterial clearance, organ injury and survival were also assessed.

Results

Burn wound infection led to a significant decline in total white blood cell and lymphocyte counts and induced organ injury and sepsis. Burn injury caused decline in CD4⁺ and CD8⁺ T cells in the spleen, which was worsened by infection. IL-15 treatment inhibited this decline and significantly increased cell numbers and activation, as determined by CD69 expression, of CD4⁺, CD8⁺, B, NK and NKT cells in the spleen and liver after burn injury. However, IL-15 SA treatment failed to prevent burn wound sepsis-induced loss of CD4⁺, CD8⁺, B, NK and NKT cells and failed to improve bacterial clearance and survival.

Conclusion

Cutaneous burn injury and infection cause significant adaptive immune dysfunction. IL-15 SA does not augment host resistance to burn wound sepsis in mice despite inducing proliferation and activation of lymphocyte subsets.     

Residues 39-56 of Stem Cell Factor Protein Sequence Are Capable of Stimulating the Expansion of Cord Blood CD34+ Cells

Background

Stem cell factor (SCF) can stimulate hematopoietic stem cell (HSC) expansion; however, the specific structural region(s) of SCF protein that are critical for this function are still unknown. A novel monoclonal antibody (named 23C8) against recombinant human SCF (rhSCF) was previously found to inhibit the ability of rhSCF to enhance HSC expansion, making it possible to identify the relevant active region to HSC.

Methods

Eleven polypeptides were synthesized, which were designed to cover the full-length of rhSCF, with overlaps that are at least 3 amino acids long. ELISA was used to identify the polypeptide(s) that specifically react with the anti-SCF. The effects of the synthetic polypeptides on human HSC expansion, or on the ability of the full-length rhSCF to stimulate cell proliferation, were evaluated ex vivo. Total cell number was monitored using hemocytometer whereas CD34⁺ cell number was calculated based on the proportion determined via flow cytometry on day 6 of culture.

Results

Of all polypeptides analyzed, only one, named P0, corresponding to the SCF protein sequence at residues 39–56, was recognized by 23C8 mAb during ELISA. P0 stimulated the expansion of CD34⁺ cells derived from human umbilical cord blood (UCB). Addition of P0 increased the numbers of total mononucleated cells and CD34⁺ cells, by ~2 fold on day 6. P0 also showed partial competition against full-length rhSCF in the ex vivo cell expansion assay.

Conclusion

Residues 39–56 of rhSCF comprise a critical functional region for its ability to enhance expansion of human UCB CD34⁺ cells. The peptide P0 is a potential candidate for further development as a synthetic substitute for rhSCF in laboratory and clinical applications.     

Pediatric Primitive Neuroectodermal Tumors of the Central Nervous System Differentially Express Granzyme Inhibitors

Background

Central nervous system (CNS) primitive neuroectodermal tumors (PNETs) are malignant primary brain tumors that occur in young infants. Using current standard therapy, up to 80% of the children still dies from recurrent disease. Cellular immunotherapy might be key to improve overall survival. To achieve efficient killing of tumor cells, however, immunotherapy has to overcome cancer-associated strategies to evade the cytotoxic immune response. Whether CNS-PNETs can evade the immune response remains unknown.

Methods

We examined by immunohistochemistry the immune response and immune evasion strategies in pediatric CNS-PNETs.

Results

Here, we show that CD4⁺, CD8⁺, γδ-T-cells, and Tregs can infiltrate pediatric CNS-PNETs, although the activation status of cytotoxic cells is variable. Pediatric CNS-PNETs evade immune recognition by downregulating cell surface MHC-I and CD1d expression. Intriguingly, expression of SERPINB9, SERPINB1, and SERPINB4 is acquired during tumorigenesis in 29%, 29%, and 57% of the tumors, respectively.

Conclusion

We show for the first time that brain tumors express direct granzyme inhibitors (serpins) as a potential mechanism to overcome cellular cytotoxicity, which may have consequences for cellular immunotherapy.     

CD4+CD25hiFOXP3+ Regulatory T Cells and Cytokine Responses in Human Schistosomiasis before and after Treatment with Praziquantel

Background

Chronic schistosomiasis is associated with T cell hypo-responsiveness and immunoregulatory mechanisms, including induction of regulatory T cells (Tregs). However, little is known about Treg functional capacity during human Schistosoma haematobium infection.

Methodology

CD4⁺CD25^hiFOXP3⁺ cells were characterized by flow cytometry and their function assessed by analysing total and Treg-depleted PBMC responses to schistosomal adult worm antigen (AWA), soluable egg antigen (SEA) and Bacillus Calmette-Guérin (BCG) in S. haematobium-infected Gabonese children before and 6 weeks after anthelmintic treatment. Cytokines responses (IFN-γ, IL-5, IL-10, IL-13, IL-17 and TNF) were integrated using Principal Component Analysis (PCA). Proliferation was measured by CFSE.

Principal Findings

S. haematobium infection was associated with increased Treg frequencies, which decreased post-treatment. Cytokine responses clustered into two principal components reflecting regulatory and Th2-polarized (PC1) and pro-inflammatory and Th1-polarized (PC2) cytokine responses; both components increased post-treatment. Treg depletion resulted in increased PC1 and PC2 at both time-points. Proliferation on the other hand, showed no significant difference from pre- to post-treatment. Treg depletion resulted mostly in increased proliferative responses at the pre-treatment time-point only.

Conclusions

Schistosoma-associated CD4⁺CD25^hiFOXP3⁺Tregs exert a suppressive effect on both proliferation and cytokine production. Although Treg frequency decreases after praziquantel treatment, their suppressive capacity remains unaltered when considering cytokine production whereas their influence on proliferation weakens with treatment.     

A Higher Frequency of CD14+CD169+ Monocytes/Macrophages in Patients with Colorectal Cancer

Objective

Monocytes and macrophages can infiltrate into tumor microenvironment and regulate the progression of tumors. This study aimed at determining the frequency of different subsets of circulating monocytes and tumor infiltrating macrophages (TIMs) in patients with colorectal cancer (CRC).

Methods

The frequency of different subsets of circulating monocytes was characterized in 46 CRC patients and 22 healthy controls (HC) by flow cytometry. The frequency of different subsets of macrophages was analyzed in TIMs from 30 tumor tissues and in lamina propria mononuclear cells (LPMCs) from 12 non-tumor tissues. The concentrations of plasma cytokines and carcinoembryonic antigen (CEA) were determined. The potential association of these measures with the values of clinical parameters was analyzed.

Results

In comparison with that in the HC, the percentages of circulating CD14⁺CD169⁺, CD14⁺CD169⁺CD163⁺ and CD14⁺CD169⁺CD206⁺ monocytes and TIMs CD14⁺CD169⁺ as well as IL-10⁺CD14⁺CD169⁺, but not IL-12⁺ CD14⁺CD169⁺ macrophages were significantly increased, accompanied by higher levels of plasma IL-10 in the CRC patients. The percentages of CD14⁺CD169⁺ circulating monocytes and TIM macrophages were associated with the stage of disease and correlated positively with the levels of plasma IL-10 and CEA in CRC patients.

Conclusion

Our data suggest that an increase in the frequency of CD14⁺CD169⁺ cells may be associated with the development and progression of CRC and is concomitant rise of both, pro-tumor (M2-like, IL-10 producing) and anti-tumor (M1-like, IL-12 producing) monocytes and infiltrating macrophages. The frequency of CD14⁺CD169⁺ circulating monocytes and infiltrating macrophages may serve as a biomarker for evaluating the pathogenic degrees of CRC.