Rat T-lymphocytes Research Articles

Immunomodulatory Effects of Bio-Clean II Herbal Remedy on C-reactive protein, Corticosterone and Antiphospholipid antibodies in Rats exposed to Purified Bacterial Lipopolysaccharide

Background: Bio-Clean II has been previously shown to fight viral infection, boost immunity, and possesses anti-inflammatory properties by regulating the serum level of inflammatory cytokines, as well as T-Helper 4 and Cytotoxic T-Lymphocytes in rats exposed to purified bacterial lipopolysaccharide (LPS). Aim: The aim of this study is to assess the effects of Bio-Clean II on the C-reactive protein (CRP), corticosterone (CORT) and anti-phospholipid antibodies (aPLs) levels in rats exposed to bacterial lipopolysaccharide (LPS) using animal model. Materials and Methods: A total of 36 male Wistar rats weighing 150g±50g (mean±SD) were purchased and randomly assigned to six (6) groups of 6 rats each. Group 1, 2, 3, 5 and 6 were induced with a single dose of 5mg/Kg of purified LPS® (E.coli 0127:B8, Sigma-Aldrich, St. Louis, USA), administered through intraperitoneal route using 1ml sterile needle and syringe, except for group 4 which served as the zero control (given water and food only throughout the experiment). Group 1 served as the inflammation control. Group 2 which served as the positive control received 50 mg diclofenac/kg [bid] and 500 mg ciprofloxacin/kg [bid] (positive control) in place of the Bio-Clean. Group 3 which served as the negative control received sterile phosphate buffer saline (PBS). While rats in group 5 and group 6 were treated orally with the herbal remedy “Bio-Clean II” for 7 days and 14 days, respectively. After which, the rats were killed and a cardiac blood specimen was taken from each rat and transferred to plain bottles to clot. Serum was obtained from the clotted blood by centrifugation. The serum levels of C-reactive protein, corticosterone and antiphospholipid antibodies were assayed using ELISA kits, supplied by Elabscience Biotechnology Inc, USA. Data generated were subjected to Statistical Package for Social Scientists-Version 20 (SPSS-20). Results: The outcome of this results show that the serum level of C-reactive protein of the 7 days (1.05±0.06ng/ml) and 14 days (0.93±0.05ng/ml) Bio-Clean II treated rats was found to be significantly lower (p=0.002 and p=0.000, respectively) when compared to the inflammation control group (1.70±0.07ng/ml). Similarly, the serum level of anti-phospholipid antibodies of the 7 days (6.40±0.67 Uml) and 14 days (4.27±0.66 U/ml) Bio-Clean II treated rats was found to be significantly lower (p=0.02 and p=0.008, respectively) when compared to the inflammation control group (16.47±1.53 Uml). Meanwhile, the corticosterone level of the 7 days Bio-clean treated rats (9.40±1.30ng/mL) was found to be non-significantly lower (p=0.812) in comparison to the inflammation control (13.50±2.50ng/mL); while that of the 14 days Bio-clean II treated rats (6.80±1.00ng/mL) was significantly lower (p=0.026). Conclusion: The outcome of this study underscores the anti-inflammatory potential of Bio-Clean II in the treatment of bacterial inflammatory diseases.

Immunomodulatory Effects of Bio-Clean II on T-Helper 4 and Cytotoxic T-Lymphocytes in Rats Exposed to Purified Bacterial Lipopolysaccharide

Introduction: Bio-Clean II has been previously shown to boost immunity, fight viral infection, and possesses anti-inflammatory properties by regulating the serum level of inflammatory cytokines in rats exposed to purified bacterial lipopolysaccharide (LPS). In this study, we investigated the immunomodulatory effect of Bio-Clean II on T-Helper 4 and Cytotoxic T-Lymphocytes in rats exposed to purified bacterial LPS. Materials and Methods: A total of 36 male Wistar rats weighing 150g±50g (mean±SD) were purchased and randomly assigned to six (6) groups of 6 rats each. Group 1, 2, 3, 5 and 6 were induced with a single dose of 5mg/Kg of purified LPS® (E. coli 0127:B8, Sigma-Aldrich, St. Louis, USA), administered through intraperitoneal route using 1ml sterile needle and syringe, except for group 4 which served as the zero control (given water and feed only throughout the experiment). Group 1 served as the inflammation control. Group 2 which served as the positive control received 50mg/Kg/bid Diclofenac +500mg/kg/bid of Ciprofloxacin. Group 3 which served as the negative control received sterile phosphate buffer saline (PBS). While rats in group 5 and group 6 were treated orally with the herbal remedy “Bio-Clean II” for 7 days and 14 days, respectively. After which, the rats were sacrificed and a cardiac blood specimen was taken from each rat by terminal bleeding from the heart. CD4 and CD8 Cell counts were evaluated using Fluorescence photomicroscopy and ELISA techniques, respectively. Results: The outcome of this investigation shows that treatment with Bio-Clean II resulted in a significant (P<0.05) increase in CD4 cell count in duration-dependent manner, 7 days (8.40±1.44 Cells/ul) and 14 days (18.40±2.66 Cells/ul), respectively, when compared to the inflammation control (4.80±1.16 Cells/ul). There was also a significant (P<0.05) decrease in CD8 cell count of the Bio-Clean II treated groups: 7 days (27.67±1.32ng/ml) and 14 days (17.44±1.00ng/ml) when compared to the inflammation control (32.93±2.52ng/ml). Conclusion: Bio-Clean Il caused significant alterations in the CD4 and CD8 counts of rats exposed to purified lipopolysaccharide. The outcome of this study, underscores the potential role of Bio-Clean Il in the treatment of bacterial inflammatory diseases, however, the molecular mechanism behind this action warrants for further investigation.

Immunomodulation of tahneeq method in IL-12 and CD8+T-Lymphocyte, an in-vivo study in neonatal rats.

Stimulation of the neonatal immune system is quite important for the proliferation and differentiation of antigen-presenting cells (APCs) and T cells. Tahneeq is a traditional method to manually rub the palatal mucosa of newborn babies with premasticated Ajwa palm dates. The present study was to investigate the tahneeq effects on IL-12 expression of dendritic cells (DCs) and blood T lymphocytes expressing CD8+ in neonatal Wistar rats. The number of 90 healthy neonatal Wistar rats have randomly divided into three groups: control group received breastmilk only, treatment group (T1) receiving breast milk + mild-scratched intensity of tahneeq, and T2 group received breastmilk + strong-scratched intensity of tahneeq on the palatal and gingival mucosa immediately after birth. Seven neonatal Wistar rats in all groups were then sacrificed in three hours after birth and days 1, 5, 7, 13, and 30 treatment. IL-12 expression in the palatal and gingival mucosa was determined using immunohistochemical staining, and blood CD8+ T-lymphocytes were quantified using a flow cytometer. One way ANOVA was used to analyze the percentage of IL-12 and CD8+ T-lymphocytes among neonatal Wistar rat groups. The T1 and T2 newborn rat groups had significantly higher IL-12 expression than the control group (p<0.001). The increased IL-12 expression in T2 groups significantly increased (p<0.001) compared to the IL-12 expression in the T1 and control groups. The percentage of CD8+ T lymphocytes in all neonatal rat groups increased on three hours after birth and day 30 treatment but remained constant on days 5 and 7 treatment and decreased on day 13 treatment. At 5, 13, and 30th days treatment, the percentage of CD8+ T lymphocytes in T1 and T2 neonatal rat groups was significantly higher (p<0.05) than that in the control group. In conclusion, the impact on systemic CD8+ T cells did not influence by the depth of the scratch. Both mild and strong tahneeq increased the systemic CD8+ T-lymphocytes in neonatal Wistar rats. The roles of anti-inflammatory cytokines and Treg cells should be further investigated to unravel those different results for the development of mucosal immunity in neonates.

Noninvasive Imaging of Acute Renal Allograft Rejection by Ultrasound Detection of Microbubbles Targeted to T-lymphocytes in Rats.

We propose CD3-antibody-mediated contrast-enhanced ultrasonography using human T-lymphocytes for image-based diagnosis of acute allograft rejection (AR) established in a rat renal transplantation model. 15 minutes after tail vein injection of 30 × 10(6) human T-lymphocytes, contrast media/microbubbles conjugated with an anti-human CD3 antibody was applied to uni-nephrectomized 10-week-old allogeneically transplanted male rats (Lewis-Brown Norway (LBN) to Lewis, aTX) and ultrasound was performed to investigate the transplanted kidney as well as the native kidney. In vivo results were confirmed via immunohistochemical stainings of CD3 after post mortem dissection. Syngeneically transplanted rats (LBN to LBN, sTX), rats with ischemia/reperfusion injury (IRI, 45 min. warm ischemia), and rats subjected to acute cyclosporin A toxicity (CSA) (cyclosporine 50 mg/kg BW for 2 days i. p.) served as controls. Accumulation of human T-lymphocytes was clearly detected by antibody-mediated sonography und was significantly increased in allografts undergoing AR (5.41 ± 1.32 A. U.) when compared to native control kidneys (0.70 ± 0.08A. U.). CD3 signal intensity was low in native kidneys, sTX (0.99 ± 0.30 A. U.), CSA (0.10 ± 0.02 A. U.) and kidneys with IRI (0.46 ± 0.29 A. U.). Quantification of the ultrasound signal correlated significantly with the T-cell numbers obtained by immunohistochemical analysis (R2 = 0.57). Contrast-enhanced sonography using CD3-antibodies is an option for quick and highly specific assessment of AR in a rat model of renal transplantation.

Erratum to: TH1/TH2 Functional Imbalance After Acute Myocardial Infarction: Coronary Arterial Inflammation or Myocardial Inflammation

The study clarified whether the T-helper (Th)1/Th2 imbalance existed only in coronary arterial inflammation or in both coronary arterial inflammation and myocardial inflammation and explored the significance of the imbalance of Th1/Th2 function after acute myocardial infarction (AMI).There are two different inflammatory processes in patients with AMI: the coronary arterial inflammation that leads to the pathogenesis of AMI and the myocardial inflammation after AMI that leads to ventricular remodeling, which are positively and negatively regulated by Th1 and Th2 lymphocytes, respectively.Peripheral blood mononuclear cells from 33 AMI patients, 22 unstable angina (UA) patients and splenocytes from 35 AMI Wistar rats were collected. Cytokine-producing Th cells were ambulatorily monitored by 3-color flow cytometry. Interferon (IFN)-gamma and interleukin (IL)-4 mRNA in the rat myocardium and chemokine receptors CCR3,CCR5 and CXCR3 mRNA on the surface of rat T-lymphocytes after AMI were measured by RT-PCR.IFN-gamma-producing T-cells significantly increased in patients with AMI and UA within 24 hours after the onset of symptom. The high ratio of IFN-gamma-producing T-cells recovered 1 week after the onset in UA patients, while it could be examined 1 week and even 1 month after the onset in AMI patients. The up-regulation of Th1 cell function is consistent with bad heart function. There was no significant difference on the frequencies of IL-4-producing T-cells between each group. 1 week, 2 weeks and 1 month after AMI, IFN-gamma mRNA increased in the myocardium of rats, but there was no significant change on global Th cell functions.Th1/Th2 functional imbalance exists in both coronary arterial inflammation and myocardial inflammation processes. The up-regulation of Th1 cell-functions may participate in the immune-mediated ventricular remodeling after AMI.

8-Bromo-cyclic inosine diphosphoribose: towards a selective cyclic ADP-ribose agonist

cADPR (cyclic ADP-ribose) is a universal Ca2+ mobilizing second messenger. In T-cells cADPR is involved in sustained Ca2+ release and also in Ca2+ entry. Potential mechanisms for the latter include either capacitative Ca2+ entry, secondary to store depletion by cADPR, or direct activation of the non-selective cation channel TRPM2 (transient receptor potential cation channel, subfamily melastatin, member 2). Here we characterize the molecular target of the newly-described membrane-permeant cADPR agonist 8-Br-N1-cIDPR (8-bromo-cyclic IDP-ribose). 8-Br-N1-cIDPR evoked Ca2+ signalling in the human T-lymphoma cell line Jurkat and in primary rat T-lymphocytes. Ca2+ signalling induced by 8-Br-N1-cIDPR consisted of Ca2+ release and Ca2+ entry. Whereas Ca2+ release was sensitive to both the RyR (ryanodine receptor) blocker RuRed (Ruthenium Red) and the cADPR antagonist 8-Br-cADPR (8-bromo-cyclic ADP-ribose), Ca2+ entry was inhibited by the Ca2+ entry blockers Gd3+ (gadolinium ion) and SKF-96365, as well as by 8-Br-cADPR. To unravel a potential role for TRPM2 in sustained Ca2+ entry evoked by 8-Br-N1-cIDPR, TRPM2 was overexpressed in HEK (human embryonic kidney)-293 cells. However, though activation by H2O2 was enhanced dramatically in those cells, Ca2+ signalling induced by 8-Br-N1-cIDPR was almost unaffected. Similarly, direct analysis of TRPM2 currents did not reveal activation or co-activation of TRPM2 by 8-Br-N1-cIDPR. In summary, the sensitivity to the Ca2+ entry blockers Gd3+ and SKF-96365 is in favour of the concept of capacitative Ca2+ entry, secondary to store depletion by 8-Br-N1-cIDPR. Taken together, 8-Br-N1-cIDPR appears to be the first cADPR agonist affecting Ca2+ release and secondary Ca2+ entry, but without effect on TRPM2.

Study of reduction rat T-lymphocytes activation and proliferation by inhibition inducible co-stimulator gene expression

To observe the change of activation and proliferation ability of rat T-lymphocytes after suppress ICOS gene expression by RNA interference. Four interference sites targeting at rat ICOS gene were designed and four pairs of oligonucleotide fragments were cloned into the pSilencer 4.1-CMV neo plasmid vectors then transfected into rat lymphocytes with cationic liposome. The expression of mRNA and protein of ICOS was detected by RT-PCR and flow cytometry. The alteration of lymphocyte proliferation ability was evaluated by mix lymphocyte reaction, and the secretion levels of IFN-gamma and IL-4 were measured by ELISA procedure. After transfection, the expression of mRNA and protein of ICOS in test groups were lower than that in control groups (P < 0.05). The ability of T-lymphocytes in proliferation was poor and the levels of IFN-gamma and IL-4 were reduced with ICOS gene shut down. RNA interference plasmid vector can suppress ICOS expression in rat T-lymphocytes significantly, and it may be useful for further study on transplantation immunity tolerance.

Physical Training Attenuates the Stress-Induced Changes in Rat T-Lymphocyte Function

Backgorund/Aims: Modulations in the immune function by stress are a well-known phenomenon. Acute restraint stress may induce impaired T-lymphocyte responses. Moderate physical training is associated with beneficial effects on immunological functions. We investigated the effects of a moderate physical training on T-lymphocyte function in rats submitted to acute restraint stress. Methods: Thirty male Wistar rats weighing 210–226 g were randomly divided into four groups: non-trained rats (NT, n = 7), and non-trained rats submitted to stress (NT + S, n = 8); trained rats (T, n = 7), and trained rats submitted to stress (T + S, n = 8). Trained rats were submitted to a program of moderate running over a period of 8 weeks. Rats subjected to restraint stress were kept immobilized in glass cylinders (8 cm in diameter and 24 cm long) during 60 min. Plasma corticosterone concentration, peripheral blood leukocyte number, indicators of apoptosis of T lymphocytes in blood and lymphoid organs, and mitogen-induced proliferation of T lymphocytes in lymphoid organs were evaluated. Results: Acute stress exposure raised plasma corticosterone concentration (p < 0.001), but not in previously trained animals. Restraint stress induced an increase in the percentage of lymphocytes in apoptosis, and a decrease in the concanavalin-A-induced proliferation of lymphocytes from the thymus and lymph nodes, and an increase in lymphocytes of the spleen. Neither of these alterations was observed in trained animals submitted to acute restraint stress. Conclusions: Our data confirm that acute restraint stress is associated with changes in T-lymphocyte function. Moreover, moderate physical training attenuates the effects of acute stress by a mechanism that involves the hypothalamic-pituitary-adrenal axis and an increase in tolerance of leukocytes.

Th1/Th2 Functional Imbalance After Acute Myocardial Infarction: Coronary Arterial Inflammation or Myocardial Inflammation

The study clarified whether the T-helper (Th)1/Th2 imbalance existed only in coronary arterial inflammation or in both coronary arterial inflammation and myocardial inflammation and explored the significance of the imbalance of Th1/Th2 function after acute myocardial infarction (AMI). There are two different inflammatory processes in patients with AMI: the coronary arterial inflammation that leads to the pathogenesis of AMI and the myocardial inflammation after AMI that leads to ventricular remodeling, which are positively and negatively regulated by Th1 and Th2 lymphocytes, respectively. Peripheral blood mononuclear cells from 33 AMI patients, 22 unstable angina (UA) patients and splenocytes from 35 AMI Wistar rats were collected. Cytokine-producing Th cells were ambulatorily monitored by 3-color flow cytometry. Interferon (IFN)-gamma and interleukin (IL)-4 mRNA in the rat myocardium and chemokine receptors CCR3,CCR5 and CXCR3 mRNA on the surface of rat T-lymphocytes after AMI were measured by RT-PCR. IFN-gamma-producing T-cells significantly increased in patients with AMI and UA within 24 hours after the onset of symptom. The high ratio of IFN-gamma-producing T-cells recovered 1 week after the onset in UA patients, while it could be examined 1 week and even 1 month after the onset in AMI patients. The up-regulation of Th1 cell function is consistent with bad heart function. There was no significant difference on the frequencies of IL-4-producing T-cells between each group. 1 week, 2 weeks and 1 month after AMI, IFN-gamma mRNA increased in the myocardium of rats, but there was no significant change on global Th cell functions. Th1/Th2 functional imbalance exists in both coronary arterial inflammation and myocardial inflammation processes. The up-regulation of Th1 cell-functions may participate in the immune-mediated ventricular remodeling after AMI.

CD28 activation does not down-regulate Cbl-b expression in aged rat T-lymphocytes

It is well known that T-lymphocyte proliferation declines ex vivo with age, and is associated with decreased expression and/or activity of stimulatory intracellular signaling proteins. However, the role of inhibitory intracellular signaling molecules like the ubiquitin ligase Cbl-b in regulating T-lymphocyte function in aging is largely unknown. Therefore, we tested the hypothesis that T-lymphocyte proliferation declines with age, in part, due to increased expression of Cbl-b. We show that young splenic T-lymphocytes reduced Cbl-b expression when stimulated with anti-CD3 and anti-CD28 antibodies, while in aged T-lymphocytes the CD28-dependent Cbl-b down-regulation did not occur. This effect did not appear to be due to reduced CD28 receptor expression on aged T-lymphocytes. The mechanism for lack of Cbl-b down-regulation may involve the proteasome since blocking proteasomal activity in young T-lymphocytes prevented Cbl-b down regulation while there was no effect in aged T-lymphocytes on Cbl-b expression. These data provide evidence for a novel mechanism by which aging reduces T-lymphocyte function.

Albumin stimulates lysophosphatidic acid acyltransferase activity in T-lymphocyte membranes.

Phosphatidic acid (PtdOH) and lysophosphatidic acid (lysoPtdOH) have been shown to enhance T-lymphocyte function. However, the FA preference and influence of acyl-CoA binding proteins on lysoPtdOH and PtdOH biosynthesis are not known. Therefore, we determined glycerol-3-phosphate acyltransferase (GPAT) and lysophosphatidic acid acyltransferase (LAT) activity in rat T-lymphocyte and liver membrane preparations in the presence of palmitoyl-CoA and oleoyl-CoA with or without BSA. We found two different properties of GPAT and LAT in whole T-lymphocyte membrane preparations relative to liver. First, T-lymphocyte basal GPAT and LAT activities were similar, whereas in liver membranes LAT activity was 10-fold higher than GPAT. Second, T-lymphocyte LAT, but not GPAT, activity was inducible (fivefold) by the addition of albumin in the presence of palmitoyl-CoA but not oleoyl-CoA. In contrast, albumin stimulated GPAT, but not LAT, activity in liver membranes in the presence of palmitoyl-CoA. These results show, for the first time, that T-lymphocyte LAT activity can be increased by the presence of an acyl-CoA binding protein, which may indicate a new important control mechanism for regulating intracellular lysoPtdOH and PtdOH levels in T-lymphocytes.

Binding, pharmacological and immunological profiles of the δ-selective opioid receptor antagonist HS 378

HS 378 is a recently developed indolomorphinan with high selectivity and antagonist potency at the δ-opioid receptor. The present study was performed to characterize the opioid binding properties and pharmacological and immunological activity of HS 378 and to compare them with those of two well-known δ-opioid receptor antagonists, naltrindole (NTI) and naltriben (NTB). In vitro opioid receptor binding profiles were determined in rat brain homogenates. HS 378 showed 4.7- and 2.4- fold higher μ/δ selectivity compared to NTI and NTB, respectively. In the [ 35S]GTPγS functional assay carried out in cell lines expressing cloned human opioid receptors, HS 378 was found to be a pure δ-opioid receptor antagonist. In vitro, exposure of HS 378 resulted in an apparent dose-related suppression of concanavalin A induced rat T-lymphocyte proliferation with an IC 50 value of 0.54 μM. NTI showed also immunosuppression with an IC 50 value of 6.93 μM, whereas NTB had no effect. The IC 50 of HS 378 was 13 times lower than that of NTI and 8 times higher than that of cyclosporin A. Taken together, our findings indicate that the small molecule HS 378 has properties that may be of therapeutic value in the setting of human inflammatory diseases.

Whole-cell patch-clamp: true perforated or spontaneous conventional recordings?

Perforated whole-cell patch-clamp recordings obtained with nystatin are frequently used to preserve intracellular integrity. However, the perforated-patch configuration may sometimes undergo a spontaneous change into the conventional whole-cell configuration, especially when lymphocytes are investigated. The electrophysiological criteria-- previously described--for establishing the existence of the perforated whole-cell configuration have been shown to be insufficient. Thus, the dye eosin, applied to the pipette solution, was tested as a tool for discriminating between the perforated and the conventional whole-cell configurations on rat T-lymphocytes. The dye never entered the cell from the pipette during the entire measurement in the perforated whole-cell configuration. In contrast, all cells in the conventional whole-cell configuration became red immediately after membrane rupture. Eosin barely changed the currents studied. The results suggest that eosin is a dye of choice for verifying a true perforated-patch configuration.

Role of central nervous system microvascular pericytes in activation of antigen-primed splenic T-lymphocytes.

The cellular constituents of the blood-brain barrier (BBB) must make finely tuned, regulatory responses to maintain microvascular homeostasis. The mechanisms by which this task is accomplished are largely unknown. However, it is thought they involve a series of cross-talk mechanisms among endothelial cells (EC), pericytes (PC), and astrocytes. During inflammation, the BBB is exposed to a number of biological response modifiers including cytokines released by infiltrating leukocytes. The response to inflammatory cytokines may alter the normal regulatory function of EC and PC. These changes may account for some of the pathological findings in central nervous system (CNS) inflammatory disease. Previous studies have shown that PC and EC may have immune potential. We have investigated the response of the PC to a variety of inflammatory cytokines. Primary rat PC constitutively express low levels of intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex (MHC) class I molecule, which can be upregulated in response to the cytokine interferon-gamma (IFNgamma). IFNgamma also induced the expression of MHC class II molecule. After induction of MHC class II molecule, CNS PC acquired the capacity to present antigen to primed syngeneic rat T-lymphocytes. Antigen presentation by PC was comparable to that seen with classic antigen-presenting cells. A small number of primary PC constitutively express low levels of vascular cell adhesion molecule-1 (VCAM-1), which was increased on exposure to tumor necrosis factor-alpha (TNFalpha). Results suggest that CNS PC respond to inflammatory cytokines, are involved in T-lymphocyte activation, and express cell surface adhesion molecules (VCAM-1, ICAM-1) that may provide costimulatory activity. It is likely that CNS PC are important in neuroimmune networks at the BBB.

H208 1-ブロモプロパンに曝露した雄ラットにおける末梢血中CD4+CD45RC+T細胞分画数の減少

H208 1-ブロモプロパンに曝露した雄ラットにおける末梢血中CD4+CD45RC+T細胞分画数の減少

Role of central opioid receptor subtypes in morphine-induced alterations in peripheral lymphocyte activity

Morphine has been shown to decrease proliferative responses of rat T-lymphocytes via central opioid receptors, however, the specific receptor subtype(s) mediating this effect have not been established. To determine the potential role of central μ opioid receptors in morphine-mediated suppression of T-lymphocyte proliferation, 20 nmol/2 μl of either morphine sulfate or DAMGO ( μ-selective agonist) were administered into the lateral ventricle of freely moving Sprague–Dawley rats. Lymphocyte proliferative response to the polyclonal T cell mitogen concanavalin A (ConA), changes in splenic natural killer cell (NK) cytolytic activity, activation of the hypothalamic–pituitary–adrenal (HPA) axis and antinociception (tail-flick latency) were examined. Results indicated that like morphine, DAMGO decreased blood lymphocyte proliferative responses by 80% and elevated both tail-flick latency and plasma corticosterone when compared to saline-treated animals. The proliferation response of lymphocytes from the spleen or thymus and splenic NK cell activity were not significantly altered by either morphine or DAMGO treatment. The effects of DAMGO were determined to be dose-dependent and completely antagonized by naltrexone pretreatment. Central administration of DPDPE ( δ-selective agonist) and U-50488 ( κ-selective agonist) produced between 40–50% suppression of blood lymphocyte proliferation responses only at a dose five times greater (100 nmol) than DAMGO treatment, without altering antinociception or activation of the HPA axis. To determine the central opioid receptor subtype(s) involved in the effects of morphine, selective opioid antagonists were microinjected into the lateral ventricle prior to morphine treatment (6 mg/kg, s.c.). CTOP ( μ-selective antagonist, 5 μg/2 μl) completely blocked the effects of morphine on all parameters measured, however, naltrindole ( δ-selective antagonist, 2 μg/2 μl) or nor-binaltorphimine ( κ-selective antagonist, 73.5 μg/2 μl) failed to block the effects of morphine. Collectively, these results provide evidence that morphine acts primarily through central μ receptors to modulate peripheral blood lymphocyte proliferation responses. Further, the antinociception and blood lymphocyte effects show greater sensitivity to opioids than either natural killer cell cytolytic activity or activation of the HPA axis.

All forms of TGF-β are co-stimulatory to rat T-lymphocytes by increasing viability and preventing apoptosis

All forms of TGF-β are co-stimulatory to rat T-lymphocytes by increasing viability and preventing apoptosis

All forms of TGF-β are co-stimulatory to rat T-lymphocytes by increasing viability and preventing apoptosis

All forms of TGF-β are co-stimulatory to rat T-lymphocytes by increasing viability and preventing apoptosis

Induction of selective cell death targeting on mature T-lymphocytes in rats by a novel immunosuppressant, FTY720

A novel immunosuppressant, FTY720, induces a rapid and marked decrease of peripheral lymphocytes, and prolong allograft survival in rats. Its mechanism of action is mediated by apoptotic cell death. In this study, we determined the time-related changes in the numbers of total lymphocytes, and the ratios of lymphocyte subpopulations in peripheral blood and lymphomyeloid organs in rats after the single oral administration of FTY720 (10 mg/kg), comparing with the effects of cyclophosphamide (80 mg/kg, ip). Total number of peripheral lymphocytes decreased significantly 3 h after the administration of the drug, while that of polymorphonuclear cells increased. T-cells were markedly decreased in number and reached a minimum of 2.3% of the control 3 days after the treatment, while B-cells reached 19.7%. T-cells decreased in spleen and liver but there was no notable change in thymus, lymph nodes, and bone marrow. The susceptibility of the cells against the drug was variant based on the type and the source of cells in vitro. Polymorphonuclear cells were the most resistant and lymph node cells the most sensitive to FTY720 after 3 h incubation with different concentration of the drug (1, 10, 100 μmol/1). When incubated with 10 μmol/1 of FTY720, B-cells were significantly higher in viability than the whole T- or CD4-cells. These results demonstrated that FTY720 induces cell death selectively in mature T-lymphocytes, especially CD4-1ymphocytes, in peripheral blood without the depression of bone marrow.

Expression of ceruloplasmin gene in human and rat lymphocytes

The acute phase plasma protein ceruloplasmin (Cp) appears to play some role in host defense. The possibility that production of Cp in extrahepatic sites may also be essential for the activation, effector functions and cytoprotection of immune cells in localized environments has received minimal attention. Here, we have surveyed various types of human and rat immune cells for the presence of Cp mRNA using RT-PCR with primers that span exons 17–19 as an initial step in addressing this possibility. Validated Cp Rt-PCR bands were obtained from RNA samples isolated from resting and activated human lymphocytes, CD4 and CD8 T-cells and B-cells. Semiquantitative RT-PCR indicated that Cp mRNA in immune cells is present at about 0.2% the level of Cp mRNA in HepG-2 human liver cell line. Various human cell lines derived from the immune system, rat splenic MNC and purified rat T-lymphocytes also constitutively express Cp gene.