Serum Selenium,Vitamin E,and Sialic Acids Concentrations in Lambs with White Muscle Disease

The aim of this study was to determine the serum concentrations of selenium, vitamin E, and total- and lipid-bound sialic acid (LBSA) in lambs with white muscle disease (WMD) before and after treatment with a commercial preparation containing selenite and vitamin E. Fifteen lambs with WMD and ten control animals were used as research materials. Blood samples were collected from both groups before- and 1 month after treatment for Se analysis by fluorimetry, whereas vitamin E and sialic acid were measured by HPLC and spectrophotometry, respectively. Compared to controls, in the diseased animals, there was a significant increase of serum total sialic acid (TSA) and LBSA, together with significant decreases of serum Se and vitamin E concentrations (p < 0.001). One month after treatment, a reversal of trend was observed with decreases of TSA and LBSA and increases of Se and vitamin E concentrations. The TSA and LBSA levels, however, remained significantly higher than those of the controls, p < 0.05 and 0.001, respectively. The Se and vitamin E concentrations of the treated animals were the same as those of controls. This is the first study on total and LBSA concentrations in lambs with WMD, showing that these markers can be used in the prognosis of the disease.     

A study of lipid- and protein- bound sialic acids for the diagnosis of bladder cancer and their relationships with the severity of malignancy

Background:

The gold standard for detection of bladder cancer is cystoscopy, which is an invasive and complicated procedure. Our study was conducted to find a tumor marker with high specificity, sensitivity, and accuracy for the diagnosis of bladder cancer.

Methods:

Serum samples were collected from 58 bladder cancer patients and 60 healthy control subjects. Levels of lipid-bound sialic acid (LBSA), and protein-bound sialic acid (PBSA) were measured spectrophotometrically by Aminoff’s method.

Results:

Mean levels of both markers were found to be significantly higher in the patients than the healthy controls. Positive correlations were observed between serum levels of lipid- (r=0.283, p<0.05) and protein- bound (r=0.56, p<0.05) sialic acids and the grade of malignancy. To differentiate patients with bladder tumors from healthy controls, cut-offpoints were determined for each of the two parameters based on Receiver Operating Characteristic (ROC) curve analysis (LBSA=21.25 mg/dL, PBSA=6.15 mg/dL). The data showed good sensitivities (LBSA=89%, PBSA=79%), specificities (LBSA=70%, PBSA=70%) and accuracies (LBSA=83%, PBSA=81%) for both markers.

Conclusion:

Measuring serum LBSA and PBSA by this simple, reproducible, noninvasive, and inexpensive method can accurately discriminate cancer patients from healthy individuals. Key Words: Urinary Bladder Neoplasms, N-Acetylneuraminic Acid, Tumor Markers     

Dichelobacter nodosus, Fusobacterium necrophorum and the epidemiology of footrot

Footrot is a debilitating disease of sheep resulting in lameness, production losses and suffering. To study the basic bacteriology of the disease, a survey was initiated across commercial farms and non-commercial research flocks to compare the bacteriology of symptomatic footrot infected sheep with healthy asymptomatic sheep. Of the 80 farmers initially contacted, 14 collected hoof swabs and returned the swabs by post. Following DNA extraction, species-specific PCR was used to identify if Dichelobacter nodosus (D. nodosus) or Fusobacterium necrophorum (F. necrophorum) species were present on each swab. Of the 42 swabs taken from symptomatic footrot infected sheep, 17 were positive for both F. necrophorum and D. nodosus, two were positive for F. necrophorum only, two for D. nodosus only and 23 swabs were negative for both F. necrophorum and D. nod osus. Of the 50 swabs received from healthy asymptomatic sheep, one was positive for F. necrophorum only and 49 were negative for both D. nodosus and F. necrophorum. This suggests that both F. necrophorum and D. nodosus are linked to footrot in the field in a pastoral farming system. If these bacteria are linked together and collectively cause footrot, this may need to be considered when managing a footrot outbreak, or maintaining a quarantine.     

Immune Response to Nocardia brasiliensis Extracellular Antigens in Patients with Mycetoma

The ability of culture-filtrate proteins to induce a cellular immune response in infected mice and humans was investigated. A crude extract culture filtrate of Nocardia brasiliensis (CFA) and five semi-purified CFA fractions (P1, P2, P3, P4, P5) were used to stimulate BALB/c mice spleen-cell cultures. The animals were divided into three groups: the first group was infected with 1 × 10⁷ CFU of N. brasiliensis in the footpad, the second group was immunized with heat-killed bacteria, and the third was injected with sterile saline. IFN-γ, IL-1α, and IL-4 concentrations were determined in culture supernatants. Protein fractions eliciting IFN-γ production in mice, as well as the CFA, were used to stimulate IFN-γ production and in vitro cell proliferation assays with peripheral blood mononuclear cells of patients with actinomycetoma by N. brasiliensis, individuals with pulmonary tuberculosis, and healthy controls. In mice, CFA and three of the protein fractions (P3, P4 and P5) induced significant IFN-γ production in the infected group. In humans, only the CFA-induced IFN-γ production and cell proliferation in the group of patients with actinomycetoma. There was no stimulation in tuberculosis patients nor healthy controls. These results suggest that some culture-filtrate antigens are recognized by patients with active actinomycetoma and do not cross-react with M. tuberculosis antigens, being therefore potential candidates to develop a diagnostic test.     

Chitosan IFN-γ-pDNA Nanoparticle (CIN) Therapy for Allergic Asthma

Background  

Allergic subjects produce relatively low amounts of IFN-γ, a pleiotropic Th-1 cytokine that downregulates Th2-associated airway inflammation and hyperresponsiveness (AHR), the hallmarks of allergic asthma. Adenovirus-mediated IFN-γ gene transfer reduces AHR, Th2 cytokine levels and lung inflammation in mice, but its use would be limited by the frequency of gene delivery required; therefore, we tested chitosan/IFN-γ pDNA nanoparticles (CIN) for in situ production of IFN-γ and its in vivo effects.     

Rapid onset of ICAM-1 expression is a marker of effective macrophages activation during infection of <Emphasis Type="Italic">Francisella tularensis</Emphasis> LVS in vitro

Francisella tularensis is capable to modulate immunobiological activities of the host cells. We focused on the expression of ICAM-1 (CD54) on J774.2 mouse macrophage cell line infected by F. tularensis live vaccine strain (LVS) in vitro as a putative marker of subsequent elimination of infection. J774.2 cell line cells were infected by F. tularensis LVS strain (multiplicity of infection, 1:100). Cell cultures were stimulated either 3 h before infection or 3 h after infection by either lipopolysaccharide (LPS) or interferon γ (IFN-γ). The expression of ICAM-1 was determined by flow cytometry 6 h after infection. The intensity of ICAM-1 expression after 6 h of J774.2 macrophage cells infection by F. tularensis is very sensitive indicator of the effective macrophages stimulation resulting in the elimination of F. tularensis infection. The mean fluorescence intensity MFI = 49.8 is set-up by our experiments as a reliable threshold of the effective elimination of F. tularensis experimental infection with 83.3% sensitivity and 96.7% specificity, respectively. Simultaneous stimulation of J774.2 macrophage cells by LPS and IFN-γ was essential to elicit the elimination of F. tularensis infection. The ICAM-1 expression determined by flow cytometry can be considered to be highly sensitive and specific approach to predict elimination of F. tularensis infection by J774.2 macrophages.     

Genetic Polymorphism of Interferon-γ, Interferon-γ Receptor, and Interferon Regulatory Factor-1 Genes in Patients with Hepatitis B Virus Infection

The natural history of hepatitis B virus (HBV) infection is probably related to host immune factors. Interferon-γ (IFN-γ) plays significant roles in immune defense. This study was undertaken to investigate the association between HBV infection and single nucleotide polymorphisms (SNPs) of IFN-γ, IFN-γ receptor (IFNGR)-1 and 2, and interferon regulatory factor (IRF)-1 genes. Between March 2002 and December 2002, 614 Korean patients were enrolled in two different groups: an HBV clearance group (n = 201), who were hepatitis B surface antigen (HBsAg) negative with antibodies to HBsAg and hepatitis B core antigen, and an HBV persistence group (n = 413), who were repeatedly HBsAg positive. We assessed polymorphisms in the IFN-γ gene at position +874, in the IFNGR-1 gene at positions −56 and +95, in the IFNGR-2 gene at the second position of codon 64 (Gln64Arg), and in the IRF-1 gene promoter (−410, −388), and the genotype distributions of the HBV clearance and persistence groups were compared. On the basis of unconditional logistic regression analysis with adjustment for age and sex, no statistically significant association with susceptibility to persistent HBV infection was observed with the IFN-γ, IFNGR-1 and 2, and IRF-1 gene polymorphisms under the codominant, dominant, and recessive models.     

Interferon-γ- and lipopolysaccharide-induced tumor necrosis factor-α is required for nitric oxide production: Tumor necrosis factor-α and nitric oxide are independently involved in the killing ofMycobacterium microti in interferon-γ-and lipopolysaccharide-treated J774A.1 cells

A comparative study was done using J774A.1 and J774A. 1-derived transfected cells (J774A.1 C.1) containing antisense tumor necrosis factor α (TNF-α) plasmid to determine the role of endogenous TNF-α on nitric oxide production as well as on the growth ofMycobacterium microti in interferon γ (IFN-γ)- and lipopolysaccharide (LPS)-treated cells. On stimulation with IFN-γ and LPS a higher level of NO was observed in J774A.1 cells compared to J774A.1 C.1 which indicated that endogenous TNF-α is required for the production of NO. Comparing the effect of IFN-γ and LPS on the intracellular growth ofM. microti, the growth-reducing activity was higher in J774A.1 cells than in J774A.1 C.1 cells and was not completely abrogated in the presence of the nitric oxide inhibitorN ^G-methyl-l-arginine (l-NMA). J774A.1 C.1 cells infected withM. microti produced a significant amount of NO when exogenous TNF-α was added along with IFN-γ and LPS and the concentration of intracellular bacteria decreased almost to that in IFN-γ and LPS treated parental J774A.1 cells. Addition of exogenous TNF-α even in the presence ofl-NMA in J774.1 C.1 cells could also partially restore intracellular growth inhibition ofM. microti caused by IFN-γ and LPS. TNF-α is probably required for the production of NO in J774A.1 cells by IFN-γ and LPS but TNF-α and NO are independently involved in the killing of intracellularM. microti with IFN-γ and LPS.     

Recognition of lameness and decisions to catch for inspection among sheep farmers and specialists in GB

Background

Epidemiological studies have used farmer estimates of the prevalence of lameness in their flocks. This assumes that farmers can identify lame sheep. Eight movie clips of sheep with locomotion from sound to moderately lame were used to investigate the ability of farmers and sheep specialists to recognise lame sheep. Each participant was asked to complete a form and indicate, for each movie clip, whether they thought the sheep was lame and whether they would catch it if it was the only lame sheep or if 2 – 5, 6 – 10 or > 10 sheep were equally lame. The farmers' responses were compared with their estimates of flock lameness prevalence and the interval between observing a lame sheep and catching it.

Results

178 farmers and 54 sheep specialists participated. Participants could identify even mildly lame sheep but made a separate decision on whether to catch them. This decision was dependent on the severity of lameness and the number of sheep lame in a group. Those who said they would catch the first lame sheep in a group were significantly more likely to catch mildly lame sheep (farmer-reported median prevalence of lameness 5% (IQR: 2%–6%)). In contrast, farmers who waited for several sheep to be lame indicated that they would only catch more severely lame sheep (farmer reported median flock lameness 11% (IQR: 9%–15%)). Approximately 15% of farmers did not catch individual lame sheep (farmer reported median flock lameness 15% (IQR: 10%–15%)). The flock prevalence of lameness increased as time to treatment increased and time to treatment was positively correlated with only catching more severely lame sheep.

Conclusion

If movie-clips are similar to the flock situation, farmers and specialists can recognise even mildly lame sheep but vary in their management from prompt treatment of the first lame sheep in a group to no individual sheep treatments. The former practices would be appropriate to minimise transmission of footrot, a common, infectious cause of lameness and so reduce its incidence. The analysis also suggests that farmers estimate lameness prevalence relatively accurately because farmers who treated the first mildly lame sheep in a group also reported the lowest prevalence of lameness in their flock.

     

Production of interferons and change of the lymphocyte subpopulation phenotype in peripheral blood at cervical papillomavirus infection

IFN-γ and IFN-α productionin vitro by peripheral blood cells activated by phytohemagglutinin or the Newcastle disease virus was impaired in patients with a benign process, cervical intraepithelial neoplasm and cancerin situ associated with human papillomavirus infection. In case of IFN-γ and IFN-α production impairment following cervical papillomavirus infection, the increased severity of disease was accompanied by remarkable IFN system suppression. The lower synthesis of both IFN correlated with changes of some lymphocyte-subpopulation phenotype in peripheral blood. Lower CD4⁺ and CD3⁺ DR⁺ T cell concentrations were observed in papillomavirus-infected patients with impaired IFN production; impaired IFN-γ production was accompanied by lower CD4/CD8 index.     

A kinetic study of gamma interferon production in herpes simplex virus-1 DNA prime-protein boost regimen comparing to DNA or subunit vaccination

The vast majority of the world’s population is infected with Herpes simplex virus (HSV). Although antiviral therapy can reduce the incidence of reactivation and asymptomatic viral shedding and limits morbidity and mortality from active disease, it cannot cure infection. Therefore, the development of an effective vaccine is an important global health priority. In this study, the induction of IFN-γ production was compared in different herpes simplex virus 1 (HSV-1) vaccines. Glycoprotein D (gD1) as a major immunogenic HSV-1 glycoprotein was chosen to our study. Balb/c mice were administered with DNA vaccine encoding gD1, subunit glycoprotein vaccine including insect cells infected by a gD1 recombinant Baculovirus, prime DNA vaccine boosted by subunit glycoprotein vaccine, inactivated KOS strain as a positive control, pcDNA3 plasmid and Sf9 cells as negative controls. Evaluation tests showed that the amount of IFN-γ mRNA at 8, 16 and 32 hours after restimulation sharply decreased whereas, the IFN-γ protein level is significantly increased. Our results revealed that at 14 days after immunization IFN-γ secretion of stimulated cells in all of the vaccinated groups dramatically raised rather than secreted IFN-γ levels in mice that were analyzed at 7 days after vaccination. In comparison to other groups; Prime-Boost immunization dramatically caused vigorous and prompt IFN-γ production at 7 days after immunization and 8 hours after restimulation. The article is published in the original.     

Resistance to the proapoptotic effects of interferon-gamma on melanoma cells used in patient-specific dendritic cell immunotherapy is associated with improved overall survival

The use of whole cell tumor vaccines and various means of loading antigen onto dendritic cells have been under investigation for over a decade. Induction of apoptosis and the exposure of immune-stimulating proteins are thought to be beneficial for the use in immunotherapy protocols, but conclusive evidence in the clinical setting has been lacking. Incubation of melanoma cell lines with interferon-gamma (IFN-γ) increased phosphatidylserine and calreticulin exposure, but not in the IFN-γ-resistant cell line Lu-1205. Short-term autologous melanoma cell lines used for loading dendritic cells for immunotherapy showed differential response to the pro-apoptotic effects of IFN-γ. These IFN-γ-treated tumor cells (TCs) were irradiated and used for loading antigen for dendritic cell therapy. A log-rank comparison of survival for patients whose TCs were found to be either sensitive (upregulated phosphatidylserine and calreticulin) or insensitive to IFN-γ revealed a strongly significant correlation to progression-free (p = 0.003) and overall survival (p = 0.002) favorably in those patients whose cell lines were resistant to the proapoptotic effect of IFN-γ. These results suggest that the use of IFN-γ in anti-melanoma dendritic cell-based immunotherapy may only be beneficial when the cells do not undergo apoptosis in response to IFN-γ and support the contention that the use of some apoptotic cells in vaccines may be detrimental.     

Rheumatoid synovial CD4+ T cells exhibit a reduced capacity to differentiate into IL-4-producing T-helper-2 effector cells

CD4⁺ memory T cells (Tm) from rheumatoid arthritis peripheral blood (RAPB) or peripheral blood from normal donors produced IL-2, whereas fewer cells secreted IFN-γ or IL-4 after a brief stimulation. RAPB Tm contained significantly more IFN-γ producers than normal cells. Many rheumatoid arthritis (RA) synovial Tm produced IFN-γ alone (40%) and fewer cells produced IL-2 or IL-4. An in vitro model was employed to generate polarized T-helper (Th) effectors. Normal and RAPB Tm differentiated into both IFN-γ- and IL-4-producing effectors. RA synovial fluid (RASF) Tm demonstrated defective responsiveness, exhibiting diminished differentiation of IL-4 effectors, whereas RA synovial tissue (RAST) Tm exhibited defective generation of IFN-γ and IL-4 producers.     

Effect of interferon-γ on the susceptibility to Fas (CD95/APO-1)-mediated cell death in human hepatoma cells

Many tumors, including hepatocellular carcinomas (HCCs), resist Fas-mediated cell death, which is one of the effector mechanisms in the host's anti-tumor response; however, this resistance can be abolished by interferon-γ (IFN-γ). IFN-γ may sensitize Fas-mediated cell death in several ways, but the exact mechanism in HCCs is uncertain. In this study, we thoroughly investigated the effect of IFN-γ on the susceptibility of one human normal liver cell line and 12 HCC cell lines to Fas-mediated cell death. We also investigated the effect of IFN-γ on the expression of various apoptosis-related genes such as the Fas/TNF-related genes, the bcl-2 family, and the caspase family of genes. Although most cell lines showed considerable constitutive expression of Fas, all tested cell lines resisted Fas-mediated cell death without IFN-γ. When cells were pretreated with IFN-γ, only three cell lines were made significantly susceptible to Fas-mediated cell death (SNU-354, SNU-387 and SNU-423); the other 10 cell lines were not affected. IFN-γ increased the mRNA expression of Fas, TRAIL and caspase-1, and surface Fas was also increased. The strongly sensitized cell lines (SNU-354, SNU-387 and SNU-423) showed a particularly potent increment in surface Fas after IFN-γ treatment (increase in surface Fas >1.7-fold). This result enabled us to conclude that a potent increment of surface Fas expression is a major sensitizing mechanism of IFN-γ. We conclude that IFN-γ cannot play a sensitizing role in most HCC cell lines and that IFN-γ makes HCC cells susceptible to Fas-mediated cell death through a marked up-regulation of surface Fas in some HCC cells. Received: 3 August 2000 / Accepted: 24 November 2000     

Role of IFN-γ +874 T/A single nucleotide polymorphism in the tuberculosis outcome among Brazilians subjects

Several genetic cytokine gene variants have been associated with host susceptibility to infectious diseases, including tuberculosis. Based upon the importance of IFN-γ in protective immunity against Mycobacterium tuberculosis, and the functional role of the IFN-γ + 874T/A single nucleotide polymorphism in IFN-γ production, we genotyped 93 Brazilian tuberculosis patients and 266 asymptomatic health care workers, including 150 individuals with a positive tuberculin skin test, and analyzed the possible association of the +874A low IFN-γ producer allele with tuberculosis occurrence. Using multivariable logistic regression models, genotype and allele frequencies of the mutant + 874A (low IFN-γ producer) allele were significantly associated with tuberculosis disease. Heterozygous carriers had a 25% increased chance, while individuals presenting the A/A homozygous genotype had an over two-fold risk of having active tuberculosis (95% CI, 1.16–5.91, P = 0.03). Despite the mixed ethnicity observed in Brazilian populations, the present data agree with observations reported in other populations and thus demonstrate that the functional +874T/A IFN-γ gene polymorphism is associated with tuberculosis in different populations.     

Effector mechanisms of interleukin-17 in collagen-induced arthritis in the absence of interferon-γ and counteraction by interferon-γ

Introduction  

Interleukin (IL)-17 is a pro-inflammatory cytokine in rheumatoid arthritis (RA) and collagen-induced arthritis (CIA). Since interferon (IFN)-γ inhibits Th17 cell development, IFN-γ receptor knockout (IFN-γR KO) mice develop CIA more readily. We took advantage of this model to analyse the mechanisms of action of IL-17 in arthritis. The role of IFN-γ on the effector mechanisms of IL-17 in an in vitro system was also investigated.     

Syndrome of arachnomelia in Simmental cattle

Background  

Epidemiological studies have used farmer estimates of the prevalence of lameness in their flocks. This assumes that farmers can identify lame sheep. Eight movie clips of sheep with locomotion from sound to moderately lame were used to investigate the ability of farmers and sheep specialists to recognise lame sheep. Each participant was asked to complete a form and indicate, for each movie clip, whether they thought the sheep was lame and whether they would catch it if it was the only lame sheep or if 2 – 5, 6 – 10 or > 10 sheep were equally lame. The farmers' responses were compared with their estimates of flock lameness prevalence and the interval between observing a lame sheep and catching it.     

NMR Based Metabonomics Study of DAG Treatment in a C2C12 Mouse Skeletal Muscle Cell Line Myotube Model of Burn-Injury

After severe burn injury, proinflammatory cytokine levels are elevated in serum and skeletal muscle, which in turn increases protein breakdown and decreases protein synthesis. In this study, C2C12 mouse skeletal muscle cell line myotubes were exposed to proinflammatory cytokines tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) as an in vitro cell-line model of catabolic response to burn injury and then treated with des-acyl ghrelin (DAG), a 28 amino acid polypeptide hormone thought to inhibit protein breakdown and increase protein synthesis, to assess its therapeutic potential. Nuclear magnetic resonance-based metabonomics was used to monitor metabolic activity of C2C12 myotubes under four treatment conditions: (1) control, (2) TNF-α/IFN-γ (TI), (3) DAG (DA), and (4) TNF-α/IFN-γ followed by DAG (TIDA) to assess the effect of DAG treatment on cellular metabolic response during basal or catabolic conditions. Twelve metabolites showed significant changes in concentrations following treatments in the hydrophilic cell extracts. Lactate (P < 10⁻⁴) and citrulline (P < 10⁻⁹) increased with TNF-α/IFN-γ treatment, indicating increased protein degradation, and returned to control levels in the TIDA group. Adenosine nucleotide levels had decreased trends in TI myotubes that returned to baseline levels after DAG treatment (P < 10⁻⁴). Guanidinoacetate and pantothenate, metabolites involved in protein synthesis and cell proliferation, had increased concentration trends following DAG treatment in both the DA and TIDA groups. Our metabonomics analysis provides further evidence that DAG counteracts the catabolic response caused by elevated muscle TNF-α/IFN-γ cytokine levels following severe burns and can play a potential therapeutic role in treatment of burn injury.     

Treatment with TNF-α and IFN-γ alters the activation of SER/THR protein kinases and the metabolic response to IGF-I in mouse c2c12 myogenic cells

The aim of this study was to compare the effects of TNF-α, IL-1β and IFN-γ on the activation of protein kinase B (PKB), p70^S6k, mitogen-activated protein kinase (MAPK) and p90 ^rsk , and on IGF-I-stimulated glucose uptake and protein synthesis in mouse C2C12 myotubes. 100 nmol/l IGF-I stimulated glucose uptake in C2C12 myotubes by 198.1% and 10 ng/ml TNF-α abolished this effect. Glucose uptake in cells differentiated in the presence of 10 ng/ml IFN-γ increased by 167.2% but did not undergo significant further modification upon the addition of IGF-I. IGF-I increased the rate of protein synthesis by 249.8%. Neither TNF-α nor IFN-γ influenced basal protein synthesis, but both cytokines prevented the IGF-I effect. 10 ng/ml IL-1β did not modify either the basal or IGF-I-dependent glucose uptake and protein synthesis. With the exception of TNF-α causing an 18% decrease in the level of PKB protein, the cellular levels of PKB, p70^S6k, p42^MAPK, p44^MAPK and p90 ^rsk were not affected by the cytokines. IGF-I caused the phosphorylation of PKB (an approximate 8-fold increase above the basal value after 40 min of IGF-I treatment), p42^MAPK (a 2.81-fold increase after 50 min), and the activation of p70^S6k and p90 ^rsk , manifesting as gel mobility retardation. In cells differentiated in the presence of TNF-α or IFN-γ, this IGF-I-mediated PKB and p70^S6k phosphorylation was significantly diminished, and the increase in p42^MAPK and p90 ^rsk phosphorylation was prevented. The basal p42^MAPK phosphorylation in C2C12 cells treated with IFN-γ was high and comparable with the activation of this kinase by IGF-I. Pretreatment of myogenic cells with IL-1β did not modify the IGF-I-stimulated phosphorylation of PKB, p70^S6k, p42^MAPK and p90 ^rsk . In conclusion: i) TNF-α and IFN-γ, but not IL-1β, if present in the extracellular environment during C2C12 myoblast differentiation, prevent the stimulatory action of IGF-I on protein synthesis. ii) TNF-α- and IFN-γ-induced IGF-I resistance of protein synthesis could be associated with the decreased phosphorylation of PKB and p70^S6k. iii) The activation of glucose uptake in C2C12 myogenic cells treated with IFN-γ is PKB independent. iv) The similar effects of TNF-α and IFN-γ on the signalling and action of IGF-I on protein synthesis in myogenic cells could suggest the involvement of both of these cytokines in protein loss in skeletal muscle.