Cross-talk between leukemic and immune cells at the tumor microenvironment in chronic lymphocytic leukemia: An update review.

Chronic lymphocytic leukemia (CLL) is a mature-type B cell malignancy correlated with significant changes and defects in both the innate and adaptive arms of the immune system, together with a high dependency on the tumor microenvironment. Overall, the tumor microenvironment (TME) in CLL provides a supportive niche for leukemic cells to grow and survive, and interactions between CLL cells and the TME can contribute to disease progression and treatment resistance. Therefore, the increasing knowledge of the complicated interaction between immune cells and tumor cells, which is responsible for immune evasion and cancer progression, has provided an opportunity for the development of new therapeutic approaches. In this review, we outline tumor microenvironment-driven contributions to the licensing of immune escape mechanisms in CLL patients.

Effects of diverse Types of Toxoplasma gondii on the outcome of Alzheimer's disease in the rat model.

Toxoplasma gondii has lifelong persistence in the brain and its cysts can affect gene expression and change diverse biological functions of neurons. Many studies indicated T. gondii infection as a risk factor for the development of behavioral changes and neurodegenerative diseases such as Alzheimer's disease (AD), although the etiopathogenetic link between them has not been exactly elucidated. The current study aimed to examine the effects of chronic toxoplasmosis infection with Types I, II, and III strains (RH, PRU, and VEG) alone and in combination on cognitive impairments and neuronal death in the Aß1-42-induced rat model of Alzheimer's disease. In the chronic toxoplasmosis phase, Alzheimer's induction was conducted by injecting Aß1-42 oligomers into the rat brain hippocampus. Behavioral tests were conducted 10 days after the AD induction. Real-time PCR was performed to evaluate T. gondii parasite burden by amplification of the B1 gene. Cytokines IL-1ß, TNF-α, and IL-10 were assayed in brain tissue supernatant using ELISA. Also, histopathological examinations were conducted to calculate inflammatory changes and neuronal death in the brain. Our findings showed that chronic toxoplasmosis infection with PRU reduces cognitive disorders, while the RH strain of T. gondii plays a destructive role and aggravates cognitive impairments in AD. Also, infection with a combination of PRU and VEG strains significantly improved spatial learning and memory impairments in Alzheimer's rat model. Histopathological findings also confirmed the results of behavioral tests, so that in AßPRU and AßPRU + VEG groups, neuronal death and infiltration of inflammatory cells were negligible and significantly less than in Alzheimer's and AßRH groups. Our findings indicate that chronic toxoplasmosis infection with PRU strain alone, also in combination with VEG strain can significantly improve cognitive disorders in AD rats, while RH strain plays a destructive role in AD pathogenesis.

Current Approaches of Immune Checkpoint Therapy in Chronic Lymphocytic Leukemia.

OPINION STATEMENT: Increasing understanding of the complex interaction between leukemic and immune cells, which is responsible for tumor progression and immune evasion, has paved the way for the development of novel immunotherapy approaches in chronic lymphocytic leukemia (CLL). One of the well-known immune escape mechanisms of tumor cells is the up-regulation of immune checkpoint molecules. In recent years, targeting immune checkpoint receptors is the most clinically effective immunotherapeutic strategy for cancer treatment. In this regard, various immune checkpoint blockade (ICB) drugs are currently been investigating for their potential effects on improving anti-tumor immune response and clinical efficacy in the hematological malignancies; however, their effectiveness in patients with CLL has shown less remarkable success, and ongoing research is focused on identifying strategies to enhance the efficacy of ICB in CLL.

Enhancement of immune responses by vaccine potential of three antigens, including ROP18, MIC4, and SAG1 against acute toxoplasmosis in mice.

Toxoplasma gondii (T. gondii) causes considerable financial losses in the livestock industry and can present serious threats to pregnant women, as well as immunocompromised patients. Therefore, it is required to design and produce an efficient vaccine for controlling toxoplasmosis. The present study aimed to evaluate the protective immunity induced by RMS protein (ROP18, MIC4, and SAG1) with Freund adjuvant, calcium phosphate nanoparticles (CaPNs), and chitosan nanoparticles (CNs) in BALB/c mice. The RMS protein was expressed in Escherichia coli (E. coli) and purified using a HisTrap HP column. Thereafter, cellular and humoral immunity was assessed by injecting RMS protein on days 0, 21, and 35 into four groups [RMS, RMS-chitosan nanoparticles (RMS-CNs), RMS-calcium phosphate nanoparticles (RMS-CaPNs), and RMS-Freund]. Phosphate buffered saline (PBS), CNs, CaPNs, and Freund served as the four control groups. The results displayed that vaccination with RMS protein and adjuvants significantly elicited the levels of specific IgG antibodies and cytokines against toxoplasmosis. There were high levels of total IgG, IgG2a, and IFN-γ in vaccinated mice, compared to those in the control groups, especially in the RMS-Freund, indicating a Th-1 type response. The vaccinated and control mice were challenged intraperitoneally with 1 × 103 tachyzoites of the T. gondii RH strain four weeks after the last injection, and in RMS-Freund and RMS-CaPNs groups, the highest increase in survival time was observed (15 days). The RMS can significantly increase Th1 and Th2 responses; moreover, multi-epitope vaccines with adjuvants can be a promising strategy for the production of a vaccine against toxoplasmosis.

Cloning, expression and characterization of a peptibody to deplete myeloid derived suppressor cells in a murine mammary carcinoma model.

BACKGROUND: Myeloid derived suppressor cells (MDSCs) are an immature heterogeneous population of myeloid lineage that attenuate the anti-tumor immune responses. Depletion of MDSCs has been shown to improve efficacy of cancer immunotherapeutic approaches. Here, we expressed and characterized a peptibody which had previously been defined by phage display technique capable of recognizing and depleting murine MDSCs. MATERIALS AND METHODS: Using splicing by overlap extension (SOE) PCR, the coding sequence of the MDSC binding peptide and linker were synthesized and then ligated into a home-made expression plasmid containing mouse IgG2a Fc. The peptibody construct was transfected into CHO-K1 cells by lipofectamine 3000 reagent and the resulting fusion protein was purified with protein G column and subsequently characterized by ELISA, SDS-PAGE and immunoblotting. The binding profile of the peptibody to splenic MDSCs and its MDSC depletion ability were then tested by flow cytometry. RESULTS: The purified peptibody appeared as a 70 KDa band in Western blot. It could bind to 98.8% of splenic CD11b+/Gr-1+ MDSCs. In addition, the intratumoral MDSCs were significantly depleted after peptibody treatment compared to their PBS-treated negative control counterparts (P < 0.05). CONCLUSION: In this study, a peptibody capable of depleting intratumoral MDSCs, was successfully expressed and purified. Our results imply that it could be considered as a potential tool for research on cancer immunotherapy.

Lymphopenia and lung complications in patients with coronavirus disease-2019 (COVID-19): A retrospective study based on clinical data.

A rapid outbreak of novel coronavirus, coronavirus disease-2019 (COVID-19), has made it a global pandemic. This study focused on the possible association between lymphopenia and computed tomography (CT) scan features and COVID-19 patient mortality. The clinical data of 596 COVID-19 patients were collected from February 2020 to September 2020. The patients' serological survey and CT scan features were retrospectively explored. The median age of the patients was 56.7 ± 16.4 years old. Lung involvement was more than 50% in 214 COVID-19 patients (35.9%). The average blood lymphocyte percentage was 20.35 ± 10.16 (normal range, 20%-50%). Although the levels of C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were high in more than 80% of COVID-19 patients; CRP, ESR, and platelet-to-lymphocyte ratio (PLR) may not indicate the in-hospital mortality of COVID-19. Patients with severe lung involvement and lymphopenia were found to be significantly associated with increased odds of death (odds ratio, 9.24; 95% confidence interval, 4.32-19.78). These results indicated that lymphopenia < 20% along with pulmonary involvement >50% impose a multiplicative effect on the risk of mortality. The in-hospital mortality rate of this group was significantly higher than other COVID-19 hospitalized cases. Furthermore, they meaningfully experienced a prolonged stay in the hospital (p = .00). Lymphocyte count less than 20% and chest CT scan findings with more than 50% involvement might be related to the patient's mortality. These could act as laboratory and clinical indicators of disease severity, mortality, and outcome.

Apoptosis and immunophenotyping of peripheral blood lymphocytes in Iranian COVID-19 patients: Clinical and laboratory characteristics.

A novel member of human coronavirus, named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has been recently recognized in China and rapidly spread worldwide. Studies showed the decreasing of peripheral blood lymphocytes in a majority of patients. In this study, we have reported the clinical features, laboratory characteristics, the frequency of peripheral blood lymphocyte subpopulations, and their apoptosis pattern in Iranian coronavirus infectious disease (COVID-19) patients. Demographic and clinical data of 61 hospitalized confirmed cases with COVID-19 at Imam Khomeini Hospital were collected and analyzed. Peripheral blood mononuclear cells were isolated from all samples and the apoptosis pattern was evaluated using Annexin V/propidium iodide method. The frequency of lymphocyte subsets, including T-CD4+ , T-CD8+ , NK, B cells, and monocytes, was measured in all patients and 31 controls by flow cytometry. Our findings demonstrated that the percentage of lymphocytes, CD4+ , and CD8+ T cells were decreased in COVID-19 patients compared with the control group. Regarding the clinical severity, the number of lymphocytes, CD4+ , CD8+ T cells, and NK cells were also decreased in severe cases when compared with mild cases. Finally, our data have also indicated the increase in apoptosis of mononuclear cells from COVID-19 patients which was more remarkable in severe clinical cases. The frequency of immune cells is a useful indicator for prediction of severity and prognosis of COVID-19 patients. These results could help to explain the immunopathogenesis of SARS-CoV-2 and introducing novel biomarkers, therapeutic strategies, and vaccine candidates.

Protective efficacy by a novel multi-epitope vaccine, including MIC3, ROP8, and SAG1, against acute Toxoplasma gondii infection in BALB/c mice.

Toxoplasma gondii is an intracellular apicomplexan parasite, which can cause a serious infectious disease in pregnant women and immunocompromised individuals. Therefore, the development of a polyvalent vaccine consisting of all stages of the parasite life cycle using the epitopes from tachyzoites, bradyzoites, and sporozoites is likely to be required for complete protective immunity. In this study, we designed protein vaccine candidate based on the prediction of specific epitopes (i.e., B cell and T cell) from three Toxoplasma gondii antigens. The MRS protein (MIC3: 30-180, ROP8: 85-185, and SAG1: 85-235) was expressed in Escherichia coli, and purification was performed using a HisTrap HP column and then we evaluated immunogenicity and protective property in BALB/c mice. Seventy-two mice were randomly divided into six groups, including three vaccinations (i.e., MRS, MRS-Freund, and MRS-Calcium Phosphate Nanoparticles (MRS-CaPNs)) and three control (i.e., Phosphate-buffered saline, Freund, and CaPNs) groups. All groups were immunized three times via subcutaneous injection within three-week intervals. In the vaccination groups, the BALB/c mice were injected with 20 µg of MRS protein for the first time and 10 µg of MRS for the next two times. Antibodies, cytokines, and splenocytes proliferation in the immunized mice were assayed using the enzyme-linked immunosorbent assay. Protective efficacy was analyzed by challenging the immunized mice with T. gondii of RH strain. Antibody, cytokine, and lymphocyte proliferation assays showed that the mice immunized with MRS induced stronger humoral and T helper type 1 cell-mediated immune responses, compared to the control mice. However, co-immunization with adjuvants (i.e., Freund and CaNPs) resulted in impaired immune responses. Effective protection against the parasite achieved an increase in survival time in the immunized mice, especially in the MRS-CaNPs group. The obtained results of the present study demonstrated that multi-epitope protein vaccination, MRS, is a potential strategy against toxoplasmosis infection. In addition, the vaccine co-delivered with CaPNs could provide an important key for vaccine candidate to control T. gondii infection.

Fluoxetine as an antidepressant medicine improves the effects of ionizing radiation for the treatment of glioma.

Radiotherapy is a cancer treatment protocol which delivers high dose of ionizing radiation (IR) to tumor. Tumor resistance and side effects induced by IR still are the major challenges in radiotherapy. The purpose of this study was to evaluate the synergistic killing effect of fluoxetine (FL) with IR on glioma cancer cell (U-87 MG), as well as radioprotective effect of FL against cellular toxicity induced by IR on non-malignant human fibroblast cell (HFFF2). Firstly, the inhibitory effects of FL on cell proliferations were evaluated in U-87 MG and HFFF2 cells. The clonogenic and MTT assays were used to evaluate the radiosensitivity and radioprotective effects of FL on cancer and non-malignant cells. The frequencies of apoptotic cells were evaluated by flow cytometry on both cancer and normal cells. Results showed that FL exhibited anti-cancer effect on glioma cells, while cellular toxicity was low in HFFF2 cells treated with FL. FL decreased the viable colonies and enhanced apoptotic cells when U-87 cells were treated with FL prior irradiation. For comparison, FL exhibited radioprotective effect through increasing cellular proliferation rate and reducing apoptosis in HFFF2 cells against IR. The results showed that FL enhanced the IR-induced glioma cancer cell death and apoptosis, whereas it exhibited a radioprotective effect on normal fibroblast cells suggesting that FL administration may improve glioma radiotherapy.

The synergistic effect of mefenamic acid with ionizing radiation in colon cancer.

Despite radiotherapy is an effective regimen in cancer treatment, resistance to tumor therapy still is a major challenge to radiotherapy and results in cancer recurrence and metastasis. Then the sensitization of tumor cells to ionizing radiation (IR) would be beneficial in cancer treatment. The aim of this study was to evaluate the synergistic effect of mefenamic acid (MEF) on colon cancer cell (HT-29) exposure to IR. HT-29 cells were treated with MEF and then exposed to IR. The synergistic effect of MEF is evaluated by clonogenic assay and flow cytometry. The productions of reactive oxygen species (ROS) were determined in irradiated and treated cells with MEF. The findings of this study showed that MEF had anti-cancer effect on colon cancer cell line and it increased the apoptosis in irradiated HT-29 cells. Also MEF reduced the number of cell colonies when HT-29 cells pre-treated with MEF and irradiated. MEF increased ROS production in irradiated cells. This additive effect of MEF with IR in killing of HT-29 cell was observed at low (10 µM) and medium (100 µM) concentrations of MEF. The present study demonstrates that MEF to be an additive effect on apoptosis and cell death induced by IR in colon cancer cells.

Correction to: The synergistic effect of mefenamic acid with ionizing radiation in colon cancer.

The original version of this article unfortunately contained a mistake. The name of "Zohreh Noaparast" is now corrected in the author group of this article.

Protective efficacy induced by DNA prime and recombinant protein boost vaccination with Toxoplasma gondii GRA14 in mice.

Toxoplasma gondii, the etiological agent of toxoplasmosis, can cause severe or lethal damages in both animals and man. So, tends to develop a more effective vaccine to prevent this disease is extremely needed and would be so prominent. The novel dense granule antigen 14 (GRA14) has been identified as a potential vaccine candidate against T. gondii infection. The aim of this study was evaluation of protective immunity induced by prime/boost vaccination strategy of GRA14 antigen with calcium phosphate (CaPNs) or Aluminum hydroxide (Alum) nano-adjuvants in BALB/c mice. The finding showed that immunization with the prime-boost strategy using plasmid DNA (pcGRA14) and recombinant protein (rGRA14) with nano-adjuvants significantly elicited levels of specific IgG antibodies and cytokines against T. gondii infection. Given that, there were the high levels of total IgG, IgG2a, IFN-γ in mice of rGRA14-CaPNs and pcGRA14 + rGRA14-CaPNs groups, which indicating a Th-1 type response. While immunization of mice with Alum based rGRA14 and pcGRA14 + rGRA14 elicited specific IgG1 and IL-4 levels, which was confirmed a Th-2 type response. Mice immunized with DNA prime-protein boost vaccine with nano-adjuvants produce more vigorous specific lymphoproliferative responses than mice immunized with other antigen formulations. In addition, the CaPNs-based prime-boost vaccine of pcGRA14 + rGRA14 showed the longest survival time in mice and the lowest parasitic load in their brain tissue compared to the other groups. The results obtained in this study show that the use of GRA14 based DNA prime-protein boost vaccination regime with CaPNs can dramatically enhanced both humoral and cellular immune responses. Therefore, this strategy can provide a promising approach to the development of an effective vaccine against T. gondii infection in the future.

Expression analysis of PD-1 and Tim-3 immune checkpoint receptors in patients with vitiligo; positive association with disease activity.

The contribution of immune checkpoint receptors in the immunopathogenesis of various autoimmune diseases has been addressed in previous reports. In this study,  the expression profile of T-cell immunoglobulin and mucin-domain containing-3 (Tim-3) and programmed cell death-1 (PD-1) checkpoint molecules was investigated in CD8+ T cells of Vitiligo patients. The association of Tim-3 and PD-1 expression with disease activity was also explored. The frequency of Tim-3+ /PD-1+ /CD8+ T cells in 30 patients with vitiligo and 30 sex- and age-matched controls was determined by flow cytometry. CD8+ T cells were then positively isolated by magnetic beads, and the mRNA expression of PD-1 and Tim-3 was determined by TaqMan-based real-time PCR. To measure the cytokines production, PBMCs were stimulated with PMA/ionomycin and concentrations of IL-4, IFN-γ and TNF-α were measured in culture supernatants by ELISA. Disease activity of patients with vitiligo was determined using the Vitiligo Area Severity Index. Patients with vitiligo have significantly shown more expression of Tim-3 and PD-1 on their CD8+ T cells compared with controls. Expression analysis of Tim-3 mRNA, but not PD-1, confirmed the results obtained from flow cytometry. While the production levels of TNF-α and IFN-γ were found higher by patients with vitiligo, IL-4 production was lower in patients compared with controls. A direct association was observed between the Tim-3 and PD-1 expression and also the production of pro-inflammatory cytokines with disease activity of patients with vitiligo. Our results indicate that Tim-3 and PD-1 are involved in immune dysregulation mechanisms of CD8+ T cells in vitiligo and may introduce as potential biomarkers for disease progression and targeted immunotherapy.

In vitro and in vivo evaluation of kojic acid against Toxoplasma gondii in experimental models of acute toxoplasmosis.

As current toxoplasmosis chemotherapies have many side effects along with toxicity on patients, we examined the anti-Toxoplasma effect of a biologically important natural antibiotic, kojic acid, in vitro and in vivo. Vero cells were incubated with different concentrations of kojic acid or pyrimethamine (positive control), and the cellular viability was determined. Next, Vero cells were infected with T. gondii (RH strain) and treated with drugs. Then, we calculated the infection index, T. gondii intracellular proliferation and the number and measure of plaque. Moreover, the effect of kojic acid on survival times, serum levels of IFN-γ and TNF-α and histopathological changes in the liver and spleen of Balb/c mice infected with T. gondii were determined. Kojic acid reduced the infection index, intracellular proliferation, the number and measure of plaque in vitro when compared to untreated infected cells. Kojic acid (100 mg/kg/day) also showed a better survival rate than infected untreated control mice (P < 0.05). IFN-γ and TNF-α secretions were significantly increased by kojic acid treatment in comparison to untreated groups (P < 0.05). In addition, its inhibitory effects on inflammatory alterations, apoptosis, and necrosis have been shown in sections of liver and spleen. We conclude that kojic acid exhibit potent anti-Toxoplasma activity with direct and indirect effects on the parasite, although further studies are needed before consideration of clinical trials.

Anti-inflammatory effects of the Portulaca oleracea hydroalcholic extract on human peripheral blood mononuclear cells.

Background: Portulaca oleracea, known as Purslane, is an annual growing herb with wide distribution around the world and traditionally used to manage several diseases. Different therapeutic properties as an anti-fever agent as well as anti-inflammatory and analgesic effects have been attributed to P. oleracea. The aim of this study was to investigate the effects of P. oleracea aerial extract on production of pro- and anti-inflammatory cytokines by human peripheral blood mononuclear cells (PBMCs). Methods: Aerial parts of P. oleracea (stems and leaves) were collected and extracted by percolation using methanol. The optimal and non-cytotoxic dose of hydro-alcoholic extract for cell culture analysis was determined by MTT assay. To assess the antiinflammatory effects of P. oleracea, PBMCs obtained from 12 normal volunteers were cultured in RPMI complete medium and cotreated with E. coli lipopolysaccharide (LPS) and P. oleracea hydro-alcoholic extract. Following 18-hour incubation, culture supernatants were harvested for measurement of secreted TNF-α, IL-6 and IL-10 by ELISA. Statistical analyses were performed using the SPSS v.20, and data analyzed by Kolmogorov-Smirnov, Mann-Whitney U, Kruskal-Wallis and post Hoc tests. P-values<0.05 were considered significant. Results: The optimal non-cytotoxic concentration of P. oleracea aerial extract was defined as 100 µg/ml based on MTT viability assay. P. oleracea hydro-alcoholic extract significantly decreased the concentration of both pro-inflammatory cytokines TNF-α and IL-6 in LPS-stimulated PBMCs (p<0.001 and p<0.001, respectively). However, the concentration of IL-10 as an anti-inflammatory cytokine, did not show any statistically significant change (p=0.390). Conclusion: Our findings highlighted the potential anti-inflammatory properties of P. oleracea in herbal medicine. Future analysis on different constituents of total extract may confirm its therapeutic effects as a promising anti-inflammatory compound.

Frequency and functional characterization of exhausted CD8+ T cells in chronic lymphocytic leukemia.

OBJECTIVES: The phenotypic and functional properties of Tim-3+ /PD-1+ /CD8+ cells as exhausted T cells were investigated in chronic lymphocytic leukemia (CLL). METHODS: Frequency of CD8+ /Tim-3+ /PD-1+ exhausted cells was determined by flow cytometry. For functional analysis, magnetic beads-isolated CD8+ T cells were stimulated with PHA and PMA/ionocymin to assess their proliferative responses and cytokine production by MTT and ELISA, respectively. Cytotoxic activity of isolated CD8+ T cells was determined using CD107a degranulation assay. RESULTS: The proportion of exhausted CD8+ T cells was significantly higher in CLL compared to controls. Isolated CD8+ T cells from CLL showed functional defects in proliferation, degranulation, and cytokines production. While IL-2, TNF-α, and IFN-γ were significantly lower in CLL patients, IL-10 was higher in the patients group. Patients with progressive clinical stages showed higher frequency and dysfunction of exhausted CD8+ T cells. CONCLUSION: Targeting immune inhibitory receptors to restore the function of tumor surrounding T cells could be helpful for immunotherapy of CLL.

Effective delivery of anti-PD-L1 siRNA with human heavy chain ferritin (HFn) in acute myeloid leukemia cell lines.

Because of the high biocompatibility, self-assembly capability, and CD71-mediated endocytosis, using human heavy chain ferritin (HFn) as a nanocarrier would greatly increase therapeutic effectiveness and reduce possible adverse events. Anti-PD-L1 siRNA can downregulate the level of PD-L1 on tumor cells, resulting in the activation of effector T cells against leukemia. Therefore, this study aimed to produce the tumor-targeting siPD-L1/HFn nanocarrier. Briefly, the HFn coding sequence was cloned into a pET-28a, and the constructed expression plasmid was subsequently transformed into E. coli BL21. After induction of Isopropyl ß-D-1-thiogalactopyranoside (IPTG), HFn was purified with Ni-affinity chromatography and dialyzed against PBS. The protein characteristics were analyzed using SDS-PAGE, Western Blot, and Dynamic light scattering (DLS). The final concentration was assessed using the Bicinchoninic acid (BCA) assay. The encapsulation was performed using the standard pH system. The treatment effects of siPD-L1/HFn were carried out on HL-60 and K-562 cancer cell lines. The RT-PCR was used to determine the mRNA expression of PD-L1. The biocompatibility and excretion of siPD-L1/HFn have also been evaluated. The expression and purity of HFn were well verified through SDS-PAGE, WB, and DLS. RT-PCR analyses also showed significant siRNA-mediated PD-L1 silencing in both HL-60 and K-562 cells. Our study suggested a promising approach for siRNA delivery. This efficient delivery system can pave the way for the co-delivery of siRNAs and multiple chemotherapies to address the emerging needs of cancer combination therapy.

Comparison of the Diagnostic Performance of Antigen B Purified from Sheep Hydatid Cyst Fluid (HCF) with Commercial ELISA Kit.

INTRODUCTION: Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by the metacestode of Echinococcus granulosus. CE is a health problem in Middle Eastern countries, such as Iran. The purpose of this study was to purify subunit 8 KDa antigen B from crude sheep hydatid cyst fluid (HCF) and compare its sensitivity and specificity with a commercial human ELISA kit (PT-Hydatid-96). METHODS: 28 sera samples were collected from hydatid cyst patients who had surgery for a hydatid cyst and had their disease confirmed by pathology after the surgery. Furthermore, 35 samples of healthy individuals with no history of hydatid cysts were collected, as were nine serum samples from parasite-infected non-CE patients. HCF was obtained from sheep fertile cysts at a Sari slaughterhouse and used as an antigen. In an indirect ELISA test, the B antigen was employed, and the results were compared to those from a commercial ELISA kit. RESULTS: The results of this study were analyzed using the Kappa test. The commercial ELISA kit showed 17 cases (23.6%) positive, 44 cases (61.1%) negative, and 11 cases (15.3%) borderline. B antigen showed that 18 (25%), 43 (59.7 %), and 11 (15.3%) were positive, negative, and borderline, respectively. One sample (1.4% of 72 total samples) of 35 serum samples from healthy individuals was positive using B antigen-based ELISA. In addition, all nine serum samples from parasite-infected non-CE patients were negative for both tests. The sensitivity and specificity of the commercial ELISA kit have been evaluated at 60.7% and 100%, respectively. For B antigenbased ELISA, these values are 64.3 and 97.7%, respectively. CONCLUSION: Antigen B produced from hydatid cyst fluid is a promising option for serological identification of hydatid cysts in both infected and healthy individuals. In an indirect ELISA test, hydatid fluid antigen could be used as a precise source of detection.

Differential regulation of B-cell proliferation by IL21 in different subsets of chronic lymphocytic leukemia.

Interleukin-21 (IL21) plays an important role in B-cell proliferation, survival and differentiation. Contrary to its stimulatory effect in normal B cells, it has been shown that it induces pro-apoptotic effect in leukemic B cells from CLL patients. Little is known regarding the biological function of IL21 in leukemic B cells from progressive and non-progressive CLL patients. In the present study, the proliferative effect of IL21 in combination with TLR9 agonist (CpG) was investigated in B cells isolated from 24 CLL patients and eight normal subjects by radioactive thymidine incorporation assay. B cells were enriched from peripheral blood mononuclear cells by negative selection using magnetic beads (MACS) and immunophenotyped by flow cytometry. Our results showed that IL21 enhanced the proliferative effects of CpG in both normal and leukemic B cells, though no significant differences were observed between CLL patients and healthy controls. Comparison between different subsets of patients revealed that while the combination of IL21 and CpG significantly inhibited the proliferation of B cells from progressive compared to non-progressive patients (p=0.001), it enhanced proliferation of leukemic B cells from IGHV mutated compared to unmutated patients (p=0.001). The inhibitory effect of IL21 on proliferation of normal and leukemic cells was found to be apoptosis-independent. Our findings suggest differential effects of IL21 in different subsets of CLL patients and suggest its potential therapeutic implication in patients with a more progressive disease.

Downregulation of IL-17-producing T cells is associated with regulatory T cell expansion and disease progression in chronic lymphocytic leukemia.

Little is known about the immunobiology of interleukin-17 (IL-17)-producing T cells and regulatory T cells (Treg) in chronic lymphocytic leukemia (CLL). In this study, the frequencies of Th17, Tc17, and CD39(+) Treg cells were enumerated in peripheral T cells isolated from 40 CLL patients and 15 normal subjects by flow cytometry. Our results showed a lower frequency of Th17 and Tc17 cells in progressive (0.99 ± 0.12 % of total CD3(+)CD4(+) cells; 0.44 ± 0.09 % of total CD8(+) cells) compared to indolent patients (1.57 ± 0.24 %, p = 0.042; 0.82 ± 0.2 %, p = 0.09) and normal subjects (1.78 ± 0.2 %, p = 0.003; 0.71 ± 0.09 %, p = 0.04). Decrease in IL-17-producing T cells was associated with CD39(+) Treg cells expansion. Variation of IL-17-producing cells and Treg cells in indolent and progressive patients was neither associated to the expression levels of Th1- and Th2-specific transcription factors T-bet and GATA-3 nor to the frequencies of IFN-γ and IL-4-producing CD4(+) T cells in a selected number of samples. Additionally, suppressive potential of CD4(+) Treg was similar in CLL patients and normal subjects. Our data indicate that progression of CLL is associated with downregulation of IL-17-producing T cells and expansion of Treg cells, implying contribution of these subsets of T cells in the progression of CLL.