Abdel-Aziz A. Zidan

Kinetics of rebounding of lymphoid and myeloid cells in mouse peripheral blood, spleen and bone marrow after treatment with cyclophosphamide.

Recently, we showed that post cyclophosphamide (CTX) microenvironment benefits the function of transferred T cells. Analysis of the kinetics of cellular recovery after CTX treatment showed that a single 4 mg/mouse CTX treatment decreased the absolute number of leukocytes in the peripheral blood (PBL) at days 3-15, and in the spleen and bone marrow (BM) at days 3-6. The absolute numbers of CD11c(+)CD11b(-) and CD11c(+)CD11b(+) dendritic cells (DCs), CD11b(+) and Ly6G(+) myeloid cells, T and B cells, CD4(+)CD25(+) T regulatory (T(reg)) cells, and NK1.1(+) cells also decreased. The cell numbers returned to control levels during the recovery phase. The absolute numbers of B cells remained low for 3 weeks. The numbers of DCs increased in PBL and spleen at day 9 but returned to control levels at day 15. These data indicate that CTX alters the cellular microenvironment in kinetics that might be precisely targeted to benefit the host.

Enhanced anticancer effect and reduced toxicity of doxorubicin in combination with thymoquinone released from poly-N-acetyl glucosamine nanomatrix in mice bearing solid Ehrlish carcinoma

&NA; The incidence of breast cancer remarkably increases all over the world. Therefore, there is a great demand to introduce new approaches into cancer treatment field. The current study was designated to evaluate the role of doxorubicin (DOX) and/or thymoquinone (TQ) nanomatrix in potentiating the cytotoxicity of either drug, and to investigate the ability of TQ to reduce cardiotoxicity of DOX in solid Ehrlich carcinoma (SEC)‐bearing mice. DOX and TQ were loaded into F2 gel, which is a fully‐acetylated poly‐N‐acetyl glucosamine nanofiber. SEC was induced in female albino mice as a model for experimentally induced breast cancer. Mice were randomly divided into eight groups (n = 10): normal control, tumor control, F2 gel, free DOX, DOX + F2 gel, free TQ, TQ + F2 gel, and DOX + TQ + F2 gel. On day 28th from tumor inoculation, mice were sacrificed and blood samples were collected for measurement of the cardiac markers; lactate dehydrogenase (LDH) and creatine kinase (CK‐MB). In addition, cardiac tissue was utilized for determination of lipid peroxide, and tumor tissue was used for measurement of anti‐apoptotic protein Bcl‐2 as well as gene expression of the tumor suppressor gene P53. DOX and/or TQ showed a significant reduction in tumor volume, cardiac markers, tumor Bcl‐2, and P53 upregulation compared to free conventional therapies. Co‐treatment with DOX + TQ + F2 gel was superior to all other groups in exerting beneficial effects. Use of TQ as an adjuvant therapy with DOX could improve its cytotoxic effects and limit its cardiac toxicity. Furthermore, loading of DOX and/or TQ into F2 gel showed a remarkable anti‐cancer activity. Graphical abstract Figure. No caption available.

Frequencies of circulating myeloid derived suppressor cells and dendritic cells in Egyptian patients with chronic Hepatitis C Virus infection undergoing treatment with IFN-α-based therapy

Background Hepatitis C Virus (HCV) is epidemic in Egypt and causes chronic hepatitis. Anti-HCVtherapy (IFN-a and Ribavirin) is only effective in 60% of patients with chronic HCV infection. This failure which is often associates with suppression of immunity results in progression of the disease and the development of hepatocellular carcinoma. Recent studies including ours have shown a positive correlation between accumulation of myeloid derived suppressor cells (MDSCs) and suppressed immunity in cancer and other diseases. Aim To assess the frequency of myeloid cells, including MDCS and dendritic cells (DCs) in chronic HCV patients and correlate it with the responses of the patients to IFNa-bases therapy. Methods

Loading of doxorubicin and thymoquinone with F2 gel nanofibers improves the antitumor activity and ameliorates doxorubicin-associated nephrotoxicity

Aims: This study aimed to elucidate the benefits of nanoformulation of doxorubicin (DOX) and thymoquinone (TQ) loaded with nanofibers of poly‐N‐acetyl glucosamine (pGlcNAc), which is known as F2 gel, over their conventional free forms. Moreover, evaluate the role of TQ in improving chemotherapeutic effect and ameliorating nephrotoxicity of DOX. Main methods: The drugs were loaded into F2 gel followed by measurement of physicochemical characterization. Next, MCF‐7 and HEPG2 cells were treated with the prepared formulations and assessed for apoptosis alongside with cellular proliferation. Furthermore, we experimentally induced Heps liver carcinoma in mice and at the end of the treatment, mice were sacrificed and serum samples were used to assess nephrotoxicity markers; blood urea nitrogen (BUN) and creatinine. Additionally, renal tissue was used for determination of oxidative markers and antioxidant enzymes; whereas, tumor tissue was utilized to measure nuclear factor kappa B (NF‐&kgr;B) and caspase 3. Key findings: Nanoformulation showed dramatic increase in apoptosis, caspase 3, and antioxidant enzymes; in contrast to, dramatic fall in cell viability, tumor volume, oxidative and nephrotoxicity markers, and NF‐&kgr;B compared to corresponding free therapies. Combined therapy was superior in conserving the measured parameters compared to other treated groups. Significance: F2 gel loaded with DOX and TQ revealed enhanced antitumor activity with minimal toxicity. Moreover, using TQ as an adjuvant with DOX could augment its cytotoxicity and ameliorate nephrotoxicity.

Chemotherapy alters the increased numbers of myeloid-derived suppressor and regulatory T cells in children with acute lymphoblastic leukemia

Abstract Introduction: Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children. The precise mechanism behind the relapse in this disease is not clearly known. One possible mechanism could be the accumulation of immunosuppressive cells, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (Tregs) which we and others have reported to mediate suppression of anti-tumor immune responses. Aim: In this study, we aimed to analyze the numbers of these cells in a population of B-ALL pediatric patients. Methods: Peripheral blood samples withdrawn from B-ALL pediatric patients (n = 45 before, during and after the induction phase of chemotherapy. Using multi parametric flow cytometric analysis. MDSCs were identified as Lin–HLA-DR–CD33+CD11b+; and Treg cells were defined as CD4+CD25+CD127–/low. Results: Early diagnosed B-ALL patients showed significant increases in the numbers of MDSCs and Tregs as compared to healthy volunteers. During induction of chemotherapy, however, the patients showed higher and lower numbers of MDSCs and Treg cells, respectively as compared to early diagnosed patients (i.e., before chemotherapy). After induction of chemotherapy, the numbers of MDSCs and Treg cells showed higher increases and decreases, respectively as compared to the numbers in patients during chemotherapy. Conclusion: Our results indicate that B-ALL patients harbor high numbers of both MDSCs and Tregs cells. This pilot study opens a new avenue to investigate the mechanism mediating the emergence of these cells on larger number of B-ALL patients at different treatment stages.

High numbers of myeloid derived suppressor cells in peripheral blood and ascitic fluid of cirrhotic and HCC patients

ABSTRACT Background: Hepatocellular carcinoma (HCC) is the 3rd most common cause of cancer-related death worldwide. It has evolved different immune escape mechanisms, which might include emergence of lymphoid and myeloid regulatory cells. Aim of this work: To determine the numbers of Myeloid-derived suppressor cells (MDSCs) in peripheral blood and ascitic fluid in cirrhosis and HCC and their relation to IFN-γ and α-fetoprotein (α-FP). Patients and methods: Sixty individuals were enrolled in this study; forty cirrhotic patients with ascites; twenty without HCC (Group I), and twenty with HCC (group II) as well as twenty healthy individuals as a control group (group III). The phenotype and numbers of MDSCs were analyzed in peripheral blood of all the individuals and ascitic fluid of the patients using flow cytometry. Intracellular IFN-γ and serum alfa-fetoprotein were measured. Results: Significant increases in the relative and the mean number of peripheral blood MDSCs were found in the cirrhosis and HCC groups than in the control group, with the HCC group showing the highest number. MDSC count was negatively correlated with IFN-γ levels, while α-FP was positively correlated with MDSC% in the HCC group. MDSC count was low in ascitic fluid of both HCC and cirrhosis groups with no significant difference between the 2 groups. Conclusion: A high frequency of MDSCs was detected in the peripheral blood of cirrhotic and HCC patients, indicating presence of immunosuppressive arms. These cells could be targeted to develop a new effective immunotherapy or an adjuvant to current therapies.

IFN-α-based treatment of patients with chronic HCV show increased levels of cells with myeloid-derived suppressor cell phenotype and of IDO and NOS

Abstract Introduction: Hepatitis C virus (HCV) infection causes chronic hepatitis, which is often associated with suppressed anti-HCV immune responses. We have recently reported accumulation of myeloid-derived suppressor cells (MDSCs) and suppressed immunity in cancer patients. Aim: The main aim of this study was to determine whether chronic HCV patients harbor high of MDSCs in general and in nonresponders to IFN-based therapy in particular as well as to analyze the immune suppressive molecules. Methods: Peripheral blood samples withdrawn from 154 patients with chronic HCV infection and were categorized into responders and nonresponders based on viral titer upon IFN-α treatment. Results: The relative and absolute numbers of MDSCs defined as Lin−/HLA-DR−/CD33+/CD11b+ increased in all HCV patients, where they were higher in nonresponders than in responders. Additionally, the levels of MDSCs after 4–6 months of treatment in responders were lower than during the course of treatment. The responders also showed higher levels of IL-2 coincided with increased numbers of dendritic cells (DCs), CD4+ and CD8+ T cells. The levels of total NOS and IDO were also higher in nonresponders as compared to responders and healthy controls, while the expression levels of CD3ζ was lower in responders as compared to nonresponders and healthy volunteers. Conclusion: Chronic HCV patients harbor high numbers of MDSCs, which are higher in nonresponders than in responders. The higher numbers of MDSCs associated with increases in the suppressing factors.

Effect of administration timing of postchemotherapy granulocyte colony-stimulating factor on host-immune cell recovery and CD8+ T-cell response

Abstract Granulocyte colony-stimulating factor (G-CSF), a hematopoietic growth factor, is a standard supportive therapy given during cancer treatment. It induces acceleration in neutrophil recovery through stimulation of mobilization of hematopoietic progenitors. Given that the latter is also induced by chemotherapy itself, the timing of administration of G-CSF postchemotherapy might impact the resultant overall effects. The present study aimed to determine the optimal timing of G-CSF postchemotherapy to exert its optimal effects on the immune cell recovery and its impact on antigen-specific CD8+ T-cell response. B6 mice were treated once with cyclophosphamide (4 mg/mouse; CTX) and then daily with G-CSF (5 g/mouse) from Days 1–5, 2–5 or 5–9 post-CTX treatment. The total numbers of various immune cell types were analyzed on Days 7, 9 and 12 post-CTX treatment. To evaluate effects on CD8+ T-cell response, a pmel-1 transgenic mouse model was used in combination with prime boost peptide vaccination therapy. The total number of white blood cells (WBC), neutrophils, monocytes, lymphocytes, granulocytes and dendritic cells (DC) were significantly increased after G-CSF treatment in particular when G-CSF was administered from Days 2–5 post-CTX treatment. Application of this timing of G-CSF and CTX treatment after adoptive transfer of T-cells followed by prime-boost vaccination with antigenic peptide did not block the expansion of the donor pmel-1 CD8+ T-cells. In conclusion, adjusting the timing of treatment with G-CSF postchemotherapy can optimize its promoting effects on recovery of myeloid cells without altering the associated antigen-specific immunity.

Increases in the numbers of cells with the phenotype of myeloid-derived suppressor and regulatory T cells in children with acute lymphoblastic leukemia

Background Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children. The precise mechanisms behind the relapse in this disease are not clearly known. One possible mechanism could be the accumulation of regulatory cells including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (T regs ) which we and others have reported to mediate suppression of anti-tumor immune responses. Few previous studies investigated the roles of T reg cells in ALL, while no studies reported the emergence of MDSCs in ALL. Aim Therefore, we aimed to analyze the frequencies and phenotype of these cells in a group of Egyptian B-ALL pediatric patients (n=45). Materials and methods MDSCs were identified as Lin − HLA-DR − CD33 + CD11b + ; and T reg cells as CD4 + CD25 + CD127 −/low using multiparametric flow cytometer. Results We found significant increases in the numbers of MDSCs and T reg cells in B-ALL patients as compared to healthy control volunteers. B-ALL patients showed significant increased numbers of MDSCs and T regs before chemotherapy when compared to healthy volunteers. The numbers of MDSCs were more increased while the numbers of T reg cells were more decreased in patients during induction of chemotherapy. The highest increase in the numbers of MDSCs was observed in patients after induction of chemotherapy, while T reg cells showed the most significant decreased numbers after induction of chemotherapy. Conclusion Our results indicate that B-ALL patients harbor both MDSCs and T reg cells, opening a new avenue to investigate the mechanism mediating the emergence of these cells in larger numbers of patients at different treatment stages.

Influence of granulocyte colony stimulating factor treatment on physiological indices in Wistar rats

Background: Granulocyte colony stimulating factor (G-CSF) is used in clinical practice to mobilize neutrophils alone or in combination with chemotherapy. However, its influence in physiological indices has not been addressed well in certain animal models such as Wistar rats. Aims: To evaluate the single and combinatorial effects of G-CSF and cyclophosphamide (CTX) on physiological indices in Wistar rat. Materials and Methods : Naïve female Wistar rats were treated with subcutaneous injection of pharmaceutical benefits scheme, (5 μL/day/rat) G-CSF for 5 consecutive days and single intraperitoneal injection of CTX (4 mg/rat). Body weights were obtained daily. Rats were sacrificed 1-day after the last injection to obtain different organ weight and to analyze the physiological indices in plasma and the liver. Results: G-CSF alone induced increases in body weight, splenomegaly, white blood cells, platelets, and alanine aminotransferase (ALT) activity. It, however, decreased neutrophils and monocytes, aspartate aminotransferase (AST) activity, red blood cells and hemoglobin level. CTX alone induced decreases in body weight, white blood cells, neutrophils, red blood cells and hemoglobin level. It, however, increased spleen weight, lymphocytes, monocytes, ALT activity and AST. G-CSF + CTX induced increases in body weight, splenomegaly, lymphocytes and ALT. It, however, decreased white blood cells, platelets number, neutrophils, monocytes, red blood cells and hemoglobin level. Conclusion : Among different physiological indices, treatment with single or combinatorial G-CSF increases the total number of white blood cells in Wistar rats which need to be considered while using this model animal disease.