T-lymphocyte Transformation Research Articles

INFLUENCE OF MODIFIED PEPTIDES FROM THE FETAL THYMUS ON THE ACTIVITY OF T-LYMPHOCYTES AND NATURAL KILLERS IN EXPERIMENTAL VIRAL HEPATITIS

The results showed that immunomodulin has a moderate regulatory effect on the spontaneous blast transformation of lymphocytes in the in vitro system. The costimulatory effect of immunomodulin in the reaction of PHA-induced blast transformation of T-lymphocytes was revealed. The data we obtained on the rather pronounced interferon-inducing properties of Sanogen developed by us and its combinations with well-known inductors -Cycloferon and Betaleukin, can be of practical use in the treatment of infectious pathology, especially viral hepatitis, when the combination of hepatoprotective, anti-inflammatory, antiviral, immunomodulatory and detoxification mechanisms of action, in the absence of toxicity and side effects, will ensure the development of sanogenetic processes in the patient's body.

Determining mechanisms of T cell leukemogenesis using E2A −/−mice

Abstract T cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy caused by the transformation of T-lymphocytes during their development. 60% of pediatric T-ALLs have ectopic expression of Tal1, a gene that promotes leukemogenesis in part by altering the function of E2A. Consistent with this, mice with germline deletion of E2A develop T-ALL that mirrors human Tal1 +T-ALL. In this study, we used mice that delete E2A at different stages in T cell development to investigate the mechanisms causing T-ALL. Mice carrying a VavCre transgene and floxed alleles of E2A (VcKO) delete E2A early in T cell development, have reduced numbers of thymocytes prior to transformation, and develop T-ALL with an average latency of 18 weeks. Mice with an LckCre transgene (LcKO) delete E2A later than VcKO mice, have replete thymi, and rarely develop T-ALL. From this, we hypothesized that 1) E2A regulates a gene program in early T cell development that is antagonistic to transformation, or 2) Having a replete, competitive thymus suppresses transformation. Pre-leukemic VcKO thymocytes showed significantly more differentially expressed genes than LcKO thymocytes, including Notch1 and Myc, and are enriched for cancer associated pathways. To determine if the lack of competition in the VcKO thymus contributes to leukemogenesis, we reconstituted VcKO thymi by transplanting wild type bone marrow into sublethally irradiated VcKO mice. BM transplant significantly increased the number and frequency of DP thymocytes and increased leukemia latency. Together, these data suggest that intrinsic loss of E2A promotes leukemogenesis by changing the gene program of early developing thymocytes and by creating a non-competitive environment that supports transformation.

The effect of biostimulants from the spleen on the activity of T-lymphocytes and natural killers ..............

The work is devoted to the study of the effect of a biostimulator and its compounds with zinc on spontaneous, PHA-induced blast transformation of T-lymphocytes in patients with chronic viral hepatitis B, as well as on the cytotoxic activity of natural killers in colon cancer, and healthy donors in the in vitro system. The results showed that the biostimulator has a moderate regulatory effect on spontaneous blast transformation of lymphocytes in the in vitro system. The costimulating effect of the biostimulator of the PHA-induced blast transformation of T-lymphocytes was revealed. A significant increase in the membranotoxic function of natural killer cells in relation to K-562 target cells was found under the influence of a biostimulator after preliminary incubation of the drug with effector cells. The biological efficiency of splenic peptides increased after the addition of zinc ions to them.

Oral glutamine inhibits tumor growth of gastric cancer bearing mice by improving immune function and activating apoptosis pathway

Gastric cancer is one of the most common cancers in the world. It has been shown that exogenous glutamine (GLN) can inhibit the growth of tumor in vivo, but the relationship between GLN and gastric cancer has not been studied. The gastric cancer bearing mouse model was constructed and taken GLN orally at the same time, and the results found that oral GLN (1 or 2 g/kg/d) significantly inhibited the growth rate of tumor and reduce the weight of tumor tissues. Immunohistochemistry showed that oral GLN significantly reduced the PCNA index, which further proved that GLN could inhibit the growth of tumor cells. At the same time, TUNEL assay showed that oral GLN significantly enhanced the apoptosis levels of tumor cells. In addition, GLN reduced GSH levels in tumor tissues, but increased the levels of GSH in plasma, improved the T-lymphocyte transformation rate and NK cell activity, significantly inhibited the secretion of TNF-α and promoted the secretion of IL-2, thus regulating the immune function in vivo. Further detection of apoptosis pathway showed that oral GLN significantly enhanced the expression of pro-apoptotic factor Bad and inhibited the expression of Bcl-2. Meanwhile, GLN significantly increased the activities of Caspase-3, Caspase-8, caspase-9 and PARP. GSH activator NAC had a similar effect to GLN, which could improve the immune function and activate apoptosis pathway, while GSH inhibitor BSO significantly blocked the regulation of GLN, destroyed the immune balance and inhibited apoptosis, but IL-2 significantly blocked the anti-apoptotic effect of BSO. Therefore, oral GLN can improve immune function and activate apoptosis pathway through GSH, and then inhibit the growth of tumor in vivo.

T‐cell blast crisis of chronic myelogenous leukemia presented with coexisting p210 and p190 BCR‐ABL transcripts and t(10;11)(q11;p15)

BackgroundBlast transformation of chronic myelogenous leukemia (CML) to T lymphoblastic lymphoma/acute lymphoblastic leukemia (T‐LBL/ALL) is rare, and the molecular mechanism is still unclear.Case reportA 28‐year‐old woman who developed T‐ALL with coexpressing both p210 and p190 BCR‐ABL transcripts five years after the initial diagnosis of CML in chronic phase. The proliferation of bone marrow was extremely active with blast cells over 20%. Chromosome analysis revealed t(9;22)(q34;q11) and t(10;11)(q25;p15). Flow immunophenotyping showed that blasts expressed CD4, CD7, CD11b, CD38, CD34, CD33, and cCD3.ConclusionIt is the first T‐cell blast of CML case with coexisting p210 and p190 as well as additional chromosome translocations. Through review this case and previous reports, we will reveal that CML patients with T‐lymphocyte transformation depend on potential molecular and pathological mechanism.

HTLV-1 CTCF-binding site is dispensable for in vitro immortalization and persistent infection in vivo

BackgroundHuman T-cell leukemia virus type 1 (HTLV-1) is the etiologic agent of adult T-cell leukemia/lymphoma (ATL) and the neurological disorder HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The exact mechanism(s) through which latency and disease progression are regulated are not fully understood. CCCTC-binding factor (CTCF) is an 11-zinc finger, sequence-specific, DNA-binding protein with thousands of binding sites throughout mammalian genomes. CTCF has been shown to play a role in organization of higher-order chromatin structure, gene expression, genomic imprinting, and serve as a barrier to epigenetic modification. A viral CTCF-binding site (vCTCF-BS) was previously identified within the overlapping p12 (sense) and Hbz (antisense) genes of the HTLV-1 genome. Thus, upon integration, HTLV-1 randomly inserts a vCTCF-BS into the host genome. vCTCF-BS studies to date have focused primarily on HTLV-1 chronically infected or tumor-derived cell lines. In these studies, HTLV-1 was shown to alter the structure and transcription of the surrounding host chromatin through the newly inserted vCTCF-BS. However, the effects of CTCF binding in the early stages of HTLV-1 infection remains unexplored. This study examines the effects of the vCTCF-BS on HTLV-1-induced in vitro immortalization and in vivo viral persistence in infected rabbits.ResultsHTLV-1 and HTLV-1∆CTCF LTR-transactivation, viral particle production, and immortalization capacity were comparable in vitro. The total lymphocyte count, proviral load, and Hbz gene expression were not significantly different between HTLV-1 and HTLV-1∆CTCF-infected rabbits throughout a 12 week study. However, HTLV-1∆CTCF-infected rabbits displayed a significantly decreased HTLV-1-specific antibody response compared to HTLV-1-infected rabbits.ConclusionsMutation of the HTLV-1 vCTCF-BS does not significantly alter T-lymphocyte transformation capacity or early in vivo virus persistence, but results in a decreased HTLV-1-specific antibody response during early infection in rabbits. Ultimately, understanding epigenetic regulation of HTLV-1 gene expression and pathogenesis could provide meaningful insights into mechanisms of immune evasion and novel therapeutic targets.

Evaluation of optimum conditions for Achyranthes bidentata polysaccharides encapsulated in cubosomes and immunological activity in vitro

Cubosomes, as biocompatible carriers in drug delivery systems, consist of curved bicontinuous lipid bilayers. With a honeycombed structure divided into two internal aqueous channels, cubosomes could be used for many bioactive ingredients. Achyranthes bidentata polysaccharides (ABPs) are isolated from the roots of Achyranthes bidentata, used in Chinese herbal medicine, and present a noticeable effect as an immunomodulator. This study investigates the optimal preparation of combined cubosome-ABP (Cub-ABP) nanoparticles using response surface methodology and explores their characteristics and stability. The encapsulation efficiency of optimized Cub-ABPs was 72.59%. In-vitro stability studies demonstrated the stability of Cub-ABPs and cubosome nanoparticles without ABPs; both were stable for up to 25days. Safe concentrations of Cub-ABPs and cubosome nanoparticles without ABPs are 104.06μg/mL and 208.13μg/mL with comparatively low cytotoxicity against lymphocytes. Moreover, the feasible immunomodulatory effects of Cub-ABPs were determined by evaluating their proliferation and change of CD4+/CD8+ ratio on splenic lymphocytes in vitro. Proliferation and flow cytometry studies revealed that, compared with free ABPs and blank cubosomes, Cub-ABPs proved more effective in promoting lymphocyte proliferation and in triggering the transformation of T-lymphocytes into Th-cells.

Effects of Microbial Aerosol in Poultry House on Meat Ducks' Immune Function.

The aim of this study was to evaluate effects of microbial aerosols on immune function of ducks and shed light on the establishment of microbial aerosol concentration standards for poultry. A total of 1800 1-d-old cherry valley ducks were randomly divided into five groups (A, B, C, D, and E) with 360 ducks in each. To obtain objective data, each group had three replications. Concentrations of airborne bacteria, fungi, endotoxin in different groups were created by controlling ventilation and bedding cleaning frequency. Group A was the control group and hygienic conditions deteriorated progressively from group B to E. A 6-stage Andersen impactor was used to detect the aerosol concentration of aerobes, gram-negative bacteria, fungi, and AGI-30 microbial air sampler detect the endotoxin, and Composite Gas Detector detect the noxious gas. In order to assess the immune function of meat ducks, immune indicators including H5 AIV antibody titer, IgG, IL-2, T-lymphocyte transformation rate, lysozyme and immune organ indexes were evaluated. Correlation coefficients were also calculated to evaluate the relationships among airborne bacteria, fungi, endotoxin, and immune indicators. The results showed that the concentration of airborne aerobe, gram-negative bacteria, fungi, endotoxin have a strong correlation to H5 AIV antibody titer, IgG, IL-2, T-lymphocyte transformation rate, lysozyme, and immune organ indexes, respectively. In addition, when the concentration of microbial aerosol reach the level of group D, serum IgG (6–8 weeks), lysozyme (4 week) were significantly higher than in group A (P < 0.05); serum IL-2 (7 and 8 weeks), T-lymphocyte transformation rate, lysozyme (7 and 8 weeks), spleen index (6 and 8 weeks), and bursa index (8 week) were significantly lower than in group A (P < 0.05 or P < 0.01). The results indicated that a high level of microbial aerosol adversely affected the immune level of meat ducks. The microbial aerosol values in group D provide a basis for recommending upper limit concentrations of microbial aerosols for healthy meat ducks.

Effect of oral administration of probiotics on growth performance, apparent nutrient digestibility and stress-related indicators in Holstein calves.

This study aimed to investigate the effect of dietary supplementation with Lactobacillus plantarum and Bacillus subtilis on growth performance, apparent nutrient digestibility and stress-related indicators in dairy calves. Twenty-four neonatal Holstein calves were randomly allocated to three treatments: a basal diet with no supplementation (control), the basal diet supplemented with 1.7 × 10(10) CFU per head per day (CFU/h.d) of L. plantarum GF103 (LB group) or the basal diet supplemented with a mixture of L. plantarum GF103 (1.7 × 10(10) CFU/h.d) and B. subtilis B27 (1.7 × 10(8) CFU/h.d) (LBS group). Dry matter intake (DMI), average daily gain (ADG), feed conversation ratio (FCR), apparent digestibility of nutrients and stress-related indicators were measured in this trail. The result indicated that no significant differences were observed in DMI or ADG (p > 0.05), but the FCR was improved in the LB group over the first 12 weeks (p > 0.05). The apparent digestibility of nutrients was not altered by probiotics in week 6 (p > 0.05), but the apparent digestibility of total phosphorus was significantly greater in the LB and LBS groups in week 8 (p > 0.05); additionally, an increase in the apparent digestibility of crude protein was detected in the LBS group (p > 0.05). Oral administration of L. plantarum alone improved the T-lymphocyte transformation rate on days 58 and 62 (p > 0.05), while adding the mixture of L. plantarum and B. subtilis increased the T-lymphocyte transformation rate (p > 0.05) but decreased the content of cortisol on day 58 (p > 0.05). No significant differences were detected between the LB and LBS groups in growth performance, apparent digestibility of nutrients and stress-related indicators (p > 0.05). The results suggested that oral administration of L. plantarum improved growth performance, nutrient digestibility and relieved weaning stress in calves, but no additional effect was obtained by supplementation with B. subtilis.

HTLV-1 Tax deregulates autophagy by recruiting autophagic molecules into lipid raft microdomains.

The retroviral oncoprotein Tax from Human T cell leukemia virus type 1 (HTLV-1), an etiological factor that causes adult T cell leukemia and lymphoma, plays a crucial role in initiating T lymphocyte transformation by inducing oncogenic signaling activation. We here report that Tax is a determining factor for dysregulation of autophagy in HTLV-1-transformed T cells and Tax-immortalized CD4 memory T cells. Tax facilitated autophagic process by activating IκB kinase complex, which subsequently recruited an autophagy molecular complex containing Beclin1 and Bif-1 to the lipid raft microdomains. Tax engaged a crosstalk between IκB kinase complex and autophagic molecule complex by directly interacting with both complexes, promoting assembly of LC3+ autophagosomes. Moreover, expression of lipid raft-targeted Bif-1 or Beclin1 was sufficient to induce formation of LC3+ autophagosomes, suggesting that Tax recruitment of autophagic molecules to lipid rafts is a dominant strategy to deregulate autophagy in the context of HTLV-1 transformation of T cells. Furthermore, depletion of autophagy molecules such as Beclin1 and PI3 kinase class III resulted in impaired growth of HTLV-1-transformed T cells, indicating a critical role of Tax-deregulated autophagy in promoting survival and transformation of virally infected T cells.

The safety and efficacy of a new anticoagulation strategy using selective in-circuit blood cooling during haemofiltration--an experimental study

Selective in-circuit blood cooling was recently shown to be an effective anticoagulation strategy during short-term haemofiltration. The aim of this study was to examine the safety of this novel method and circuit life. Fourteen pigs were randomly assigned to receive continuous haemofiltration with anticoagulation achieved either by selective cooling of an extracorporeal circuit (ECC) (COOL; n = 8) or through systemic heparinization (HEPARIN; n = 6). Before (T0) as well as 1 (TP1) and 6 h (TP6) after starting the procedure the following parameters were assessed: animal status, variables reflecting haemostasis, oxidative stress, inflammation and function of blood elements. All animals remained haemodynamically stable with unchanged body core temperature and routine biochemistry. Regional ECC blood cooling did not alter clinically relevant markers of haemostasis, namely activated partial thromboplastin and prothrombin times, thrombin-antithrombin complexes, von Willebrand factor and plasminogen activator inhibitor-1. Platelet aggregability, serum levels of free haemoglobin, leukocyte count, oxidative burst and blastic transformation of T-lymphocytes were all found to be stable over the treatment period in both groups. ECC blood cooling affected neither plasma malondialdehyde concentrations (a surrogate marker of oxidative stress) nor plasma levels of cytokines (tumour necrosis factor-α, interleukin-6 and -10). While the patency of all circuits treated with systemic heparin was well maintained within the pre-selected period of 24 h, the median filter lifespan in the COOL group was 17 h. Utilizing clinically relevant markers, selective in-circuit blood cooling was demonstrated to be a safe and feasible means of achieving regional anticoagulation in healthy pigs. The long-term safety issues warrant further evaluation.

Marek’s disease virus-encoded microRNAs: genomics, expression and function

MicroRNAs (miRNAs) are the recently discovered small non-coding RNA molecules that have post-transcriptional regulatory functions in many important biological processes. A large number of miRNAs have been found to be encoded by viral genomes, especially in herpesviruses. Previous research regarding miRNAs encoded by herpesviruses, including Marek's disease virus (MDV), has demonstrated their involvement in lytic replication, latent infection, T-lymphocyte transformation and tumorigenesis. MDV is an oncogenic alphaherpesvirus, with the ability to induce tumors in natural hosts; however, formation of these tumors can be prevented by immunization with attenuated or nonpathogenic forms of the virus. Marek's disease is considered to be a good biomedical model for investigating the biology, genetics, and immunology of tumorigenesis. In this paper, we review the discovery and identification of MDV-encoded miRNAs, along with their genomics, expression profiles, and currently known functions. We also discuss the prospects and techniques possibly applicable to the further investigation of the biological roles of MDV-encoded miRNAs.

Abstract 5347: Disruption of PDZ protein-protein interactions inhibits Tax transformation and HTLV-1 infection capacities

Abstract Approximately 15 to 25 million people worldwide are infected with human T-cell leukaemia virus type 1 (HTLV-1) or type 2 (HTLV-2). One of the viral regulatory proteins, Tax, is critical for viral transcription and replication and has been clearly implicated in T-lymphocyte transformation in vitro and oncogenesis in vivo. Elucidation of the metabolic processes involved in Tax activity is thus of prime importance for understanding the pathogenesis induce by HTLV. Interactions between Tax and a selected group of PDZ containing proteins are associated with the transforming activities of Tax1 as well as persistent HTLV-1 infection. We demonstrate that the PDZ-containing protein syntenin-1 and −2, known to interact with Heparan sulfate proteoglycan receptor syndecan-1 and to connect cytoskeletal proteins, interact with HTLV-1 Tax and with the HTLV-1 receptor GLUT-1 but not with HTLV-2 Tax. Both PDZ1 and 2 domains of syntenins are required for Tax binding. We also show that syntenin-2 co-localizes with Tax in nuclear speckles. Furthermore, we demonstrate that an antagonist for PDZ protein- protein interaction suppresses Tax-induced transformation and prevents T cell infection by HTLV-1. Thus, disruption of PDZ protein-protein interaction may provide new therapeutic opportunities for HTLV-1 induced diseases. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5347.

Video time-lapse microscopy of human laryngeal carcinomas in vitro

Video time-lapse microscopy of human laryngeal carcinomas in vitro Twelve human laryngeal carcinomas and 14 normal vocal cord epithelia were studied in vitro by the method of tissue culture incorporating video time-lapse microscopy. Different events were photographed by taking ‘stills’ from the television monitor during play-back. Outgrowths from both tumour and normal explants formed only as monolayers. Mitoses were mainly found to be localized approximately mid-way between explant and the edge of the outgrowth. Some cells were seen to become suddenly active producing oscillating blebs and sometimes they detached themselves from the monolayer culture and changed appearance. This was more prevalent in the tumour cultures. In both tumour and normal cell cultures lymphocytes were observed and their normal chemokinetic movement was changed into a rapid chemotactic attraction by the presence of a mitotic epithelial cell. These lymphocytes appear to represent T-suppressor cells. The present study has shown that primary tissue culture can be a valuable tool in the study of laryngeal carcinoma. The interaction between mitotic tumour cells and lymphocytes may represent a transformation of T-lymphocytes into LAK cells.

Inhibition of ALK enzymatic activity in T-cell lymphoma cells induces apoptosis and suppresses proliferation and STAT3 phosphorylation independently of Jak3

Aberrant expression of the ALK tyrosine kinase as a chimeric protein with nucleophosmin (NPM) and other partners plays a key role in malignant cell transformation of T-lymphocytes and other cells. Here we report that two small-molecule, structurally related, quinazoline-type compounds, WHI-131 and WHI-154, directly inhibit enzymatic activity of NPM/ALK as demonstrated by in vitro kinase assays using a synthetic tyrosine-rich oligopeptide and the kinase itself as the substrates. The inhibition of NPM/ALK activity resulted in malignant T cells in suppression of their growth, induction of apoptosis and inhibition of tyrosine phosphorylation of STAT3, the key effector of the NPM/ALK-induced oncogenesis. We also show that the STAT3 tyrosine phosphorylation is mediated in the malignant T cells by NPM/ALK independently of Jak3 kinase as evidenced by the presence of STAT3 phosphorylation in the NPM/ALK-transfected BaF3 cells that do not express detectable Jak3 and in the NPM/ALK-positive malignant T cells with either Jak3 activity impaired by a pan-Jak or Jak3-selective inhibitor or Jak3 expression abrogated by Jak3 siRNA. The above results represent the ‘proof-of-principle' experiments with regard to the ALK enzymatic activity as an attractive therapeutic target in T-cell lymphomas and other malignancies that express the kinase in an active form.

Characterization of Lck-Binding Elements in the Herpesviral Regulatory Tip Protein

Herpesvirus saimiri encodes a tyrosine kinase interacting protein (Tip) that binds to T-cell-specific tyrosine kinase Lck via multiple sequence motifs and controls its activity. The regulation of Lck by Tip represents a key mechanism in the transformation of human T-lymphocytes during herpesviral infection. In this study, the interaction of Tip with the regulatory SH3 and SH2 domains of Lck was investigated by biophysical and computational techniques. NMR spectroscopy of isotopically labeled Tip(140-191) revealed that the interaction with the LckSH3 domain is not restricted to the classical proline-rich motif, but also involves the C-terminally adjacent residues which pack into a hydrophobic pocket on the surface of the SH3 domain, thus playing a likely role in mediating binding specificity. Fluorescence binding studies of Tip further demonstrate that Tyr127 in its phosphorylated form represents a strong ligand of the LckSH2 domain, indicating the presence of an additional Lck interaction motif. In contrast, Tyr114, known to be essential for STAT-3 binding, does not interact with the LckSH2 domain, showing that the tyrosines in Tip exhibit distinct binding specificity. The existence of numerous interaction sites between Tip and the regulatory domains of Lck implies a complex regulatory mechanism and may have evolved to allow a gradual regulation of Lck activity in different pathogenic states.

Structural investigation of the binding of a herpesviral protein to the SH3 domain of tyrosine kinase Lck.

Herpesvirus saimiri codes for a tyrosine kinase interacting protein (Tip) that interacts with both the SH3 domain and the kinase domain of the T-cell-specific tyrosine kinase Lck via two separate motifs. The activation of Lck by Tip is considered as a key event in the transformation of human T-lymphocytes during herpesviral infection. We investigated the interaction of proline-rich Tip peptides with the LckSH3 domain starting with the structural characterization of the unbound interaction partners. The solution structure of the LckSH3 was determined by heteronuclear multidimensional nuclear magnetic resonance (NMR) spectroscopy using 44 residual dipolar couplings in addition to the conventional experimental restraints. Circular dichroism spectroscopy proved that the polyproline helix of Tip is already formed prior to SH3 binding and is conformationally stable. NMR titration experiments point out three major regions of the Tip-Lck interaction comprising the RT loop, the n-src loop, and a helical turn preceding the last strand of the beta-sheet. Further changes of the chemical shifts were observed for the N- and C-terminal beta-strands of the SH3 domain, indicating additional contacts outside the proline-rich segment or subtle structural rearrangements transmitted from the binding site of the proline helix. Fluorescence spectroscopy shows that Tip binds to the SH3 domains of several Src kinases (Lck, Hck, Lyn, Src, Fyn, Yes), exhibiting the highest affinities for Lyn, Hck, and Lck.

Effects of Daidzein on Body Weight Gain, Serum IGF-I Level and Cellular Immune Function in Intact Male Piglets

male piglets at 5-6 weeks old with similar body weight (BW) were randomly assigned into the experimental (EXP) and control (CON) groups. The animals in EXP received intro-muscular injection with daidzein (DA) at the dose of 0.5 mg DA per kg start BW on day 1. The same procedures were repeated once every 3 days for eight times. The animals in CON received the injection only with same volume of control peanut oil. The animals were weighted on day 14 and 28 and the blood samples were obtained at different stages of the treatment for determining IGF-I levels and blood parameters. At the end of the experiment, the thymus and spleen from all the animals were surgically taken out and weighted. The results showed that BW and average daily gain (ADG) were not significantly different between the groups in term of the whole period, but ADG between days 14-28 was higher in EXP than in CON (p 0.05) and 23.46% (p<0.05), respectively, higher than those in CON. The weights of thymus and spleen, the ratios of their weights to BW and red blood count (RBC) did not significantly differ between the groups at all stages. White blood count (WBC) in EXP steadily increased from day 22, reached its apex on day 24, which was higher than in CON (p<0.05) and its own levels on day 20 and 22 (p<0.01 or p<0.05), and remained higher on the later time (p=0.058). The results of percentage of T-Lymphocytes also demonstrated similar trend to WBC, but T- Lymphocyte transformation rate (%) appeared no significant change between the groups. In conclusion, Daidzein could stimulate male piglet growth and elevate serum IGF-I levels at certain stages of the treatment. It could also increase WBC and T-Lymphocyte rates, but had no significant impacts on RBC and T-Lymphocyte transformation rate. (Asian-Aust. J. Anim. Sci. 2002. Vol 15, No. 7 : 1066-1070)

Synthesis of [ARG14 17 19 20jdeacetyl-thymosin a1 and its immunological effect on the impaired T­ lymphocytes of uremic patients

Abstract: A deacetyl-thymosin cx1analogue containing four arginines at positions 14, 17, 19, and 20, instead of four lysines was synthesized by the manual solid-phase method. The synthetic [Arg14 17 19 20 deacetyl-thymosin cx1 and deacetyl-thymosin cx1 were tested for the effect on impaired T-lymphocyte transformation by phytohemagglutinin in uremic patients suffering from recurrent infectious diseases. The restoring activity on the impaired phytohemagglutinin stimulation of T-lymphocytes was obtained after incubation of peripheral lymphocytes isolated from uremic patients with the synthetic [Arg14•17•19•20] deacetyl-thymosin cx1. This analogue exhibited a far stronger restoring effect than that of our synthetic deacetyl-thymosin ex1. Abbreviations used: Obzl, benzyl estrer; Bzl, benzyl; Boe, tert-butoxycarbonyl; Mts, mesitylene-2-sulfonyl; DCC, N, N' -dicyclohexylcarbodiimide; HOBT, 1-hydro-xybenzotriazole; DMF, dimethylformamide; Et3N, triethylamine; AcOH, acetic acid; TFA, trifluoroacetic acid; TLC, thin-layer chromatography; HPLC, high­ performance liquid chromatography; PHA, phytohemagglutinin; SDS, sodium dodecyl sulfate; PBS, phosphate­ buffered saline; RPMI, Rosewell Park Memorial Institute; FCS, fetal calf serum; E-rosette, a rosette with sheep erythrocytes.

Human T-cell leukemia virus type 2 tax mutants that selectively abrogate NFkappaB or CREB/ATF activation fail to transform primary human T cells.

Human T-cell leukemia virus (HTLV) Tax protein has been implicated in the HTLV oncogenic process, primarily due to its pleiotropic effects on cellular genes involved in growth regulation and cell cycle control. To date, several approaches attempting to correlate Tax activation of the CREB/activating transcription factor (ATF) or NFkappaB/Rel transcriptional activation pathway to cellular transformation have yielded conflicting results. In this study, we use a unique HTLV-2 provirus (HTLV(c-enh)) that replicates by a Tax-independent mechanism to directly assess the role of Tax transactivation in HTLV-mediated T-lymphocyte transformation. A panel of well-characterized tax-2 mutations is utilized to correlate the respective roles of the CREB/ATF or NFkappaB/Rel signaling pathway. Our results demonstrate that viruses expressing tax-2 mutations that selectively abrogate NFkappaB/Rel or CREB/ATF activation display distinct phenotypes but ultimately fail to transform primary human T lymphocytes. One conclusion consistent with our results is that the activation of NFkappaB/Rel provides a critical proliferative signal early in the cellular transformation process, whereas CREB/ATF activation is required to promote the fully transformed state. However, complete understanding will require correlation of Tax domains important in cellular transformation to those Tax domains important in the modulation of gene transcription, cell cycle control, induction of DNA damage, and other undefined activities.