Early alpha interferon (IFN-alpha) therapy against hepatitis C virus (HCV) rescues polyfunctional, virus-specific memory CD8(+) T cells, but whether immune restoration is possible during late therapy remains controversial. We compared immune restoration of HCV-specific memory T cells in patients who cleared HCV infection spontaneously and following early or late IFN therapy. Multifunctional CD4(+) and CD8(+) memory T cells were detected in spontaneous resolvers and in individuals treated early following an acute infection. In contrast, limited responses were detected in patients treated during chronic infection, and the phenotype of HCV-specific cells was influenced by autologous viral sequences. Our data suggest that irreversible damage to the HCV-specific memory T-cell response is associated with chronic HCV infection.

BACKGROUND:

We recently demonstrated that type I Interferon (IFN) rescues in vitro, human B-lymphocytes from apoptosis via PI3Kδ/Akt, Rho-A, NFκB and Bcl-2/BclXL. In the present study we extended our work to clarify, in vivo, the role of type I IFN signalling on the circulating and lymphoid organs homing lymphocytes.

METHODOLOGY:

Two groups of mice 13 in each were set: type I IFN signalling blocked mice injected with anti-IFNAR1 antagonist antibody (10 mg/kg body weight) once/day for up to 20 days, and control group were injected with vehicle alone.

RESULTS:

Flow cytometry analysis to monitor the blood lymphocyte phenotype and proliferation have shown a significant decrease in CD45R/B220(+) [corrected] B cells, CD4(+) and CD8(+) T cells in treated animals. Furthermore, the proliferative capacities of these lymphocyte subsets were significantly decreased in treated animals compared to those of control mice. Marked reduction in the plasma levels of IL-2 and IL-7 (cytokines important for the development of T and B cells) but not of IL-6 or IL-10 was observed in treated mice and this may a cause for emergence decrease in B and T cell numbers. Immunohistochemical studies have further shown a marked reduction in the numbers of CD20(+) B cells in spleen and Peyer's patches and CD3(+) T cells in thymus of treated animals. Moreover, electron microscopy examinations have revealed a loss of lymphocytes with characteristic features of apoptosis.

CONCLUSION:

Our data confirmed that the in vivo inhibition of type I IFN signaling induce decrease in the numbers and defective functions of circulating and lymphoid organs homing lymphocytes providing a strong evidence for the protective effects of type 1 IFNs (IFN-α/β) on B and T lymphocytes.

Copyright © 2010 S. Karger AG, Basel.

BACKGROUND:

We recently demonstrated that type I Interferon (IFN) rescues in vitro, human B-lymphocytes from apoptosis via PI3Kδ/Akt, Rho-A, NFκB and Bcl-2/BclXL. In the present study we extended our work to clarify, in vivo, the role of type I IFN signalling on the circulating and lymphoid organs homing lymphocytes.

METHODOLOGY:

Two groups of mice 13 in each were set: type I IFN signalling blocked mice injected with anti-IFNAR1 antagonist antibody (10 mg/kg body weight) once/day for up to 20 days, and control group were injected with vehicle alone.

RESULTS:

Flow cytometry analysis to monitor the blood lymphocyte phenotype and proliferation have shown a significant decrease in CD45R/B220(+) [corrected] B cells, CD4(+) and CD8(+) T cells in treated animals. Furthermore, the proliferative capacities of these lymphocyte subsets were significantly decreased in treated animals compared to those of control mice. Marked reduction in the plasma levels of IL-2 and IL-7 (cytokines important for the development of T and B cells) but not of IL-6 or IL-10 was observed in treated mice and this may a cause for emergence decrease in B and T cell numbers. Immunohistochemical studies have further shown a marked reduction in the numbers of CD20(+) B cells in spleen and Peyer's patches and CD3(+) T cells in thymus of treated animals. Moreover, electron microscopy examinations have revealed a loss of lymphocytes with characteristic features of apoptosis.

CONCLUSION:

Our data confirmed that the in vivo inhibition of type I IFN signaling induce decrease in the numbers and defective functions of circulating and lymphoid organs homing lymphocytes providing a strong evidence for the protective effects of type 1 IFNs (IFN-α/β) on B and T lymphocytes.

Copyright © 2010 S. Karger AG, Basel.

BACKGROUND:

We recently demonstrated that type I Interferon (IFN) rescues in vitro, human B-lymphocytes from apoptosis via PI3Kδ/Akt, Rho-A, NFκB and Bcl-2/BclXL. In the present study we extended our work to clarify, in vivo, the role of type I IFN signalling on the circulating and lymphoid organs homing lymphocytes.

METHODOLOGY:

Two groups of mice 13 in each were set: type I IFN signalling blocked mice injected with anti-IFNAR1 antagonist antibody (10 mg/kg body weight) once/day for up to 20 days, and control group were injected with vehicle alone.

RESULTS:

Flow cytometry analysis to monitor the blood lymphocyte phenotype and proliferation have shown a significant decrease in CD45R/B220(+) [corrected] B cells, CD4(+) and CD8(+) T cells in treated animals. Furthermore, the proliferative capacities of these lymphocyte subsets were significantly decreased in treated animals compared to those of control mice. Marked reduction in the plasma levels of IL-2 and IL-7 (cytokines important for the development of T and B cells) but not of IL-6 or IL-10 was observed in treated mice and this may a cause for emergence decrease in B and T cell numbers. Immunohistochemical studies have further shown a marked reduction in the numbers of CD20(+) B cells in spleen and Peyer's patches and CD3(+) T cells in thymus of treated animals. Moreover, electron microscopy examinations have revealed a loss of lymphocytes with characteristic features of apoptosis.

CONCLUSION:

Our data confirmed that the in vivo inhibition of type I IFN signaling induce decrease in the numbers and defective functions of circulating and lymphoid organs homing lymphocytes providing a strong evidence for the protective effects of type 1 IFNs (IFN-α/β) on B and T lymphocytes.

Copyright © 2010 S. Karger AG, Basel.

BACKGROUND:

We recently demonstrated that type I Interferon (IFN) rescues in vitro, human B-lymphocytes from apoptosis via PI3Kδ/Akt, Rho-A, NFκB and Bcl-2/BclXL. In the present study we extended our work to clarify, in vivo, the role of type I IFN signalling on the circulating and lymphoid organs homing lymphocytes.

METHODOLOGY:

Two groups of mice 13 in each were set: type I IFN signalling blocked mice injected with anti-IFNAR1 antagonist antibody (10 mg/kg body weight) once/day for up to 20 days, and control group were injected with vehicle alone.

RESULTS:

Flow cytometry analysis to monitor the blood lymphocyte phenotype and proliferation have shown a significant decrease in CD45R/B220(+) [corrected] B cells, CD4(+) and CD8(+) T cells in treated animals. Furthermore, the proliferative capacities of these lymphocyte subsets were significantly decreased in treated animals compared to those of control mice. Marked reduction in the plasma levels of IL-2 and IL-7 (cytokines important for the development of T and B cells) but not of IL-6 or IL-10 was observed in treated mice and this may a cause for emergence decrease in B and T cell numbers. Immunohistochemical studies have further shown a marked reduction in the numbers of CD20(+) B cells in spleen and Peyer's patches and CD3(+) T cells in thymus of treated animals. Moreover, electron microscopy examinations have revealed a loss of lymphocytes with characteristic features of apoptosis.

CONCLUSION:

Our data confirmed that the in vivo inhibition of type I IFN signaling induce decrease in the numbers and defective functions of circulating and lymphoid organs homing lymphocytes providing a strong evidence for the protective effects of type 1 IFNs (IFN-α/β) on B and T lymphocytes.

Copyright © 2010 S. Karger AG, Basel.

BACKGROUND:

Epidemiological studies have shown that the offspring of mothers who experience diabetes mellitus during pregnancy are seven times more likely to develop health complications later in life compared to offspring born to nondiabetic mothers.

AIM OF THE STUDY:

We investigated whether supplementation with a natural antioxidant (thymoquinone; TQ) in female rats with streptozotocin (STZ)-induced gestational diabetes (GD) improved diabetic complications and T cell immune responses in their offspring.

METHODS:

Three groups of female rats were tested: nondiabetics, diabetics treated with TQ during pregnancy and lactation periods and diabetics that were not treated with TQ (n=10 female rats in each group).

RESULTS:

Our data demonstrated a significant decrease in the numbers of neonates born to diabetic rats compared with those born to control rats. GD led to macrosomic pups with several postpartum complications, such as a significant increase in plasma levels of the pro-inflammatory cytokines IL-1β, IL-6, and TNF-α (but not of IL-10); a marked decrease in the plasma level of IL-2; a marked reduction in the proliferative capacity of superantigen (SEB)-stimulated T-lymphocytes; and an obvious reduction in the number of circulating and thymus homing T cells. TQ supplementation of diabetic mothers during pregnancy and lactation periods had an obvious and significant effect on the number and mean body weight of neonates. Furthermore, TQ significantly restored the IL-2 level and T cell proliferation and subsequently rescued both circulating and thymus homing T cells in the offspring.

CONCLUSIONS:

Our data suggest that nutritional supplementation of GD mothers with the natural antioxidant TQ during pregnancy and lactation periods improves diabetic complications and maintains an efficient T cell immune response in their offspring, providing a protective effect in later life.

BACKGROUND:

Studies have demonstrated that vitamin C supplementation enhances the immune system, prevents DNA damage, and decreases the risk of a wide range of diseases. Other study reported that leukocyte vitamin C level was low in diabetic individuals compared with nondiabetic controls.

AIM OF THE WORK:

To study the effect of vitamin C on oxidative stress, blood lipid profile, and T-cell responsiveness during streptozotocin (STZ)-induced type I diabetes mellitus.

METHODS:

Thirty male Sprague-Dawley rats were randomly split into three groups. The first served as a control group (n = 10) in which rats were injected with the vehicle alone. The second (n = 10) and the third groups (n = 10) were rendered diabetic by intraperitoneal (i.p.) injection of single doses of STZ (60 mg/kg body weight). The third group was supplemented with vitamin C (100 mg/kg body weight) for 2 months.

RESULTS:

T lymphocytes from the diabetic rats were found to be in a stunned state, with a decreased surface expression of the CD28 costimulatory molecule, low levels of phosphorylated AKT, altered actin polymerization, diminished proliferation and cytokine production, and, eventually, a marked decrease in abundance in the periphery. Vitamin C was found to significantly decrease the elevated levels of blood hydroperoxide, glucose, cholesterol, triglycerides and low-density lipoprotein (LDL) in diabetic rats. Furthermore, it was found to restore CD28 expression, AKT phosphorylation, actin polymerization, and polyfunctional T cells (IFN-γ- and IL-2-producing cells that exhibit a high proliferation capacity).

CONCLUSION:

Vitamin C treatment restores and reconstitutes polyfunctional, long-lived T cells in diabetic rats.

BACKGROUND:

Long and persistent uncontrolled diabetes tends to degenerate the immune system and leads to an increased incidence of infection. Whey proteins (WPs) enhance immunity during early life and have a protective role in some immune disorders. In this study, the effects of camel WP on the chemotaxis of B and T cells to CXCL12 and CCL21 in diabetic mice were investigated.

RESULTS:

Flow cytometric analysis of the surface expressions of CXCR4 (CXCL12 receptor) and CCR7 (CCL21 receptor) on B and T cells revealed that the surface expressions of CXCR4 and CCR7 were not significantly altered in diabetic and WP-supplemented diabetic mice compared with control mice. Nevertheless, B and T lymphocytes from diabetic mice were found to be in a stunned state, with a marked and significant (P < 0.05) decrease in CXCL12- and CCL21-mediated actin polymerization and subsequently, a marked decrease in their chemotaxis. WP supplementation in the diabetes model was found to significantly increase CXCL12- and CCL21-mediated actin polymerization and chemotaxis in both B and T cells.

CONCLUSION:

Our data revealed the benefits of WP supplementation in enhancing cytoskeletal rearrangement and chemotaxis in B and T cells, and subsequently improving the immune response in diabetic mice.

BACKGROUND:

Thymoquinone (TQ), the major active component of the medicinal herb Nigella sativa Linn., has been described as a chemopreventive and chemotherapeutic compound.

METHODS:

In this study, we investigated the effect of TQ on survival, actin cytoskeletal reorganization, proliferation and signal transduction in multiple myeloma (MM) cells.

RESULTS:

We found that TQ induces growth arrest in both MDN and XG2 cells in a dose- and time-dependent manner. TQ also inhibited CXC ligand-12 (CXCL-12)-mediated actin polymerization and cellular proliferation, as shown by flow cytometry. The signal transducer and activator of transcription (STAT) and B-cell lymphoma-2 (Bcl-2) signaling pathways may play important roles in the malignant transformation of a number of human malignancies. The constitutive activation of the STAT3 and Bcl-2 pathways is frequently observed in several cancer cell lines, including MM cells. Using flow cytometry, we found that TQ markedly decreased STAT3 phosphorylation and Bcl-2 and Bcl-XL expression without modulating STAT5 phosphorylation in MM cells. Using western blotting, we confirmed the inhibitory effect of TQ on STAT3 phosphorylation and Bcl-2 and Bcl-XL expression.

CONCLUSIONS:

Taken together, our data suggests that TQ could potentially be applied toward the treatment of MM and other malignancies.

revious studies have shown that thymoquinone (TQ) exerts protective effects in some models of pesticide-induced immunotoxicity. However, no data exist regarding its possible modulatory effect during imidacloprid (IC)-induced toxicity. Therefore, the aim of this study was to investigate the impact of TQ on IC-induced immunotoxicity. Sixty adult male albino rats were divided into three groups of twenty animals each. The control group was given distilled water orally, while the IC-treated group was orally administered 0.01 LD(50 )(0.21 mg/kg body weight) of IC insecticide daily for 28 days. The animals in the third group (IC/TQ group) received the same IC dose as the IC-treated group for 28 days in addition to an intraperitoneal (I.P.) injection of TQ (1 mg/kg) once every 7 days. We found that IC induced significant increases (P < 0.05) in total leukocyte counts, total immunoglobulins (Igs) (especially IgGs), the hemagglutination of antibodies, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and malondialdehyde (MDA) compared to the control group. In contrast, significant decreases (P < 0.05) in phagocytic activity, chemokine expression and chemotaxis were observed in the IC-treated group, as were severe histopathological lesions in the liver, spleen and thymus. Notably, TQ supplementation ameliorated the biochemical, histopathological, and immunological changes induced by IC by increasing phagocytic activity, chemokinesis, chemotaxis, immunoglobulin levels, and the hemagglutination of antibodies, as well as by decreasing hepatic enzymes and serum MDA levels. Taken together, our data reveal the benefits of TQ supplementation for ameliorating IC toxicity by decreasing oxidative stress and enhancing immune efficiency.