The relationships of change in work climate with changes in burnout and depression: a 2-year longitudinal study of Chinese mental health care workers.

Mental health care workers face heavy emotional demand and are prone to work burnout. Work burnout has been associated with poor mental health and work climate, which refers to individual perceptions about work setting. The purpose of this study was to examine whether intra-individual changes in work climate were associated with intra-individual changes in burnout and depression over two years. The present sample included Chinese mental health care workers (N = 312; mean age = 38.6, SD = 9.9) working in a psychosocial rehabilitation institution. The participants completed questionnaires on work climate, work burnout and depression at seven time points across two years. Parallel process latent growth modeling was used to analyze the associations of change between work climate and burnout and depression. Work climate displayed a logarithmic decreasing trend while burnout and depression displayed logarithmic increasing trends over two years. Baseline levels of work climate were negatively and moderately associated with baseline levels of burnout and depression (r = -.44 to -.60, p < .01). Changes in work climate were negatively and moderately associated with change in burnout (r = -.43, p < .01) and change in depression (r = -.31, p < .05). Change in burnout was positively and strongly associated (r = .58, p < .01) with change in depression. The current results support temporal relationships among changes in work climate, burnout and depression across time. Practical implications for future preventive work in burnout interventions were discussed within this population.

Incidence of central nervous system metastases in patients with HER2-positive metastatic breast cancer treated with pertuzumab, trastuzumab, and docetaxel: results from the randomized phase III study CLEOPATRA.

BACKGROUND: Results from the phase III trial CLEOPATRA in human epidermal growth factor receptor 2-positive first-line metastatic breast cancer demonstrated significant improvements in progression-free and overall survival with pertuzumab, trastuzumab, and docetaxel over placebo, trastuzumab, and docetaxel. We carried out exploratory analyses of the incidence and time to development of central nervous system (CNS) metastases in patients from CLEOPATRA. PATIENTS AND METHODS: Patients received pertuzumab/placebo: 840 mg in cycle 1, then 420 mg; trastuzumab: 8 mg/kg in cycle 1, then 6 mg/kg; docetaxel: initiated at 75 mg/m(2). Study drugs were administered i.v. every 3 weeks. The log-rank test was used for between-arm comparisons of time to CNS metastases as first site of disease progression and overall survival in patients with CNS metastases as first site of disease progression. The Kaplan-Meier approach was used to estimate median time to CNS metastases as first site of disease progression and median overall survival. RESULTS: The incidence of CNS metastases as first site of disease progression was similar between arms; placebo arm: 51 of 406 (12.6%), pertuzumab arm: 55 of 402 (13.7%). Median time to development of CNS metastases as first site of disease progression was 11.9 months in the placebo arm and 15.0 months in the pertuzumab arm; hazard ratio (HR) = 0.58, 95% confidence interval (CI) 0.39-0.85, P = 0.0049. Overall survival in patients who developed CNS metastases as first site of disease progression showed a trend in favor of pertuzumab, trastuzumab, and docetaxel; HR = 0.66, 95% CI 0.39-1.11. Median overall survival was 26.3 versus 34.4 months in the placebo and pertuzumab arms, respectively. Treatment comparison of the survival curves was not statistically significant for the log-rank test (P = 0.1139), but significant for the Wilcoxon test (P = 0.0449). CONCLUSIONS: While the incidence of CNS metastases was similar between arms, our results suggest that pertuzumab, trastuzumab, and docetaxel delays the onset of CNS disease compared with placebo, trastuzumab, and docetaxel. CLINICALTRIALSGOV: NCT00567190.

A brief structured education programme enhances self-care practices and improves glycaemic control in Malaysians with poorly controlled diabetes.

We assessed the effectiveness of a brief structured diabetes education programme based on the concept of self-efficacy on self-care and glycaemic control using single-blind study design. One hundred and sixty-four participants with poorly controlled diabetes from two settings were randomized using computer-generated list into control (n = 82) and intervention (n = 82) groups, of which 151 completed the study. Monthly interventions over 12 weeks addressed the self-care practices of diet, physical activity, medication adherence and self-monitoring of blood glucose (SMBG). These self-care practices were assessed at Weeks 0 and 12 using pre- and post-questionnaires in both groups together with glycated haemoglobin A1c (HbA1c) and diabetes knowledge. In the intention-to-treat analysis (n = 164), the intervention group improved their SMBG (P = <0.001), physical activity (P = 0.001), HbA1c (P = 0.03), diabetes knowledge (P = <0.001) and medication adherence. At Week 12, HbA1c difference adjusted for SMBG frequency, medication adherence and weight change remained significant (P = 0.03) compared with control group. For within group comparisons, diabetes knowledge (P = <0.001), HbA1c level (P = <0.001), SMBG (P = <0.001) and medication adherence (P = 0.008) improved from baseline in the intervention group. In the control group, only diabetes knowledge improved (P = <0.001). These findings can contribute to the development of self-management diabetes education in Malaysia.

Genetics and vaccine efficacy: host genetic variation affecting Marek's disease vaccine efficacy in White Leghorn chickens.

Marek's disease (MD) is a T-cell lymphoma disease of domestic chickens induced by MD virus (MDV), a naturally oncogenic and highly contagious cell-associated α-herpesvirus. Earlier reports have shown that the MHC haplotype as well as non-MHC genes are responsible for genetic resistance to MD. The MHC was also shown to affect efficiency of vaccine response. Using specific-pathogen-free chickens from a series of 19 recombinant congenic strains and their 2 progenitor lines (lines 6(3) and 7(2)), vaccine challenge experiments were conducted to examine the effect of host genetic variation on vaccine efficacy. The 21 inbred lines of White Leghorns share the same B*2 MHC haplotype and the genome of each recombinant congenic strain differs by a random 1/8 sample of the susceptible donor line (7(2)) genome. Chickens from each of the lines were divided into 2 groups. One was vaccinated with turkey herpesvirus strain FC126 at the day of hatch and the other was treated as a nonvaccinated control. Chickens of both groups were inoculated with a very virulent plus strain of MDV on the fifth day posthatch. Analyses of the MD data showed that the genetic line significantly influenced MD incidence and days of survival post-MDV infection after vaccination of chickens (P<0.01). The protective indices against MD varied greatly among the lines with a range of 0 up to 84%. This is the first evidence that non-MHC host genetic variation significantly affects MD vaccine efficacy in chickens in a designed prospective study.

Neuropeptide-induced androgen independence in prostate cancer cells: roles of nonreceptor tyrosine kinases Etk/Bmx, Src, and focal adhesion kinase.

The bombesin/gastrin-releasing peptide (GRP) family of neuropeptides has been implicated in various in vitro and in vivo models of human malignancies including prostate cancers. It was previously shown that bombesin and/or neurotensin (NT) acts as a survival and migratory factor(s) for androgen-independent prostate cancers. However, a role in the transition from an androgen-dependent to -refractory state has not been addressed. In this study, we investigate the biological effects and signal pathways of bombesin and NT on LNCaP, a prostate cancer cell line which requires androgen for growth. We show that both neurotrophic factors can induce LNCaP growth in the absence of androgen. Concurrent transactivation of reporter genes driven by the prostate-specific antigen promoter or a promoter carrying an androgen-responsive element (ARE) indicate that growth stimulation is accompanied by androgen receptor (AR) activation. Furthermore, neurotrophic factor-induced gene activation was also present in PC3 cells transfected with the AR but not in the parental line which lacks the AR. Given that bombesin does not directly bind to the AR and is known to engage a G-protein-coupled receptor, we investigated downstream signaling events that could possibly interact with the AR pathway. We found that three nonreceptor tyrosine kinases, focal adhesion kinase (FAK), Src, and Etk/BMX play important parts in this process. Etk/Bmx activation requires FAK and Src and is critical for neurotrophic factor-induced growth, as LNCaP cells transfected with a dominant-negative Etk/BMX fail to respond to bombesin. Etk's activation requires FAK, Src, but not phosphatidylinositol 3-kinase. Likewise, bombesin-induced AR activation is inhibited by the dominant-negative mutant of either Src or FAK. Thus, in addition to defining a new G-protein pathway, this report makes the following points regarding prostate cancer. (i) Neurotrophic factors can activate the AR, thus circumventing the normal growth inhibition caused by androgen ablation. (ii) Tyrosine kinases are involved in neurotrophic factor-mediated AR activation and, as such, may serve as targets of future therapeutics, to be used in conjunction with current antihormone and antineuropeptide therapies.

Identification of tumor-specific paclitaxel (Taxol)-responsive regulatory elements in the interleukin-8 promoter.

Paclitaxel (Taxol) is a novel chemotherapeutic drug that is effective against breast and ovarian cancers. Although the primary target of paclitaxel is microtubules, its efficacy exceeds that of conventional microtubule-disrupting agents, suggesting that it may have additional cellular effects. Previously, we demonstrated that paclitaxel can induce interleukin-8 (IL-8) gene expression at the transcriptional level in subsets of human ovarian cancer lines. In this as well as the previous report, we present evidence that this ability is not linked to the lipopolysaccharide pathway of IL-8 gene induction. The present study identifies the cis-acting elements and trans-acting factors involved in this induction by transfecting DNA constructs containing the 5'-flanking region of the IL-8 gene linked to the chloramphenicol acetyltransferase reporter gene into paclitaxel-responsive and nonresponsive ovarian cancer cells (responsiveness refers to the IL-8 response). Paclitaxel only activated the IL-8 promoter in responsive cells. The AP-1 and NF-kappaB binding sites in the IL-8 promoter are required for activation by paclitaxel; in contrast, a C/EBP site required for IL-8 promoter activation in other cell types is not involved. Gel shift assays demonstrate that paclitaxel causes a marked increase in protein binding to the NF-kappaB and AP-1 consensus binding sequences in the paclitaxel-responsive ovarian cells, but not the nonresponsive cells. The induction of NF-kappaB and AP-1 binding is reduced by the addition of protein kinase C inhibitors and cyclic AMP effector, respectively. These results demonstrate a molecular mechanism for cell-specific paclitaxel-induced IL-8 gene expression which may have clinical relevance.

Marek's disease virus-induced skin leukosis in scaleless chickens: tumor development in the absence of feather follicles.

Marek's disease virus (MDV) is an oncogenic cell-associated herpesvirus that causes T-cell lymphoma in chickens. Lymphoproliferative neoplasms in Marek's disease (MD) occur in various organs and tissues, including the viscera, peripheral nerves, skin, gonads, and musculatures. MDV is restrictively produced in the feather follicle epithelial (FFE) cells, and it gains access to the external environment via infected cells or as infectious enveloped cell-free virus particles. The goals of the present study were to 1) determine whether the MDV-induced skin lesions are neoplastic in nature or inflammatory reactions to viral infection, 2) determine whether physical presence of feather follicles (FF) is necessary for skin tumor development, and 3) study the role of skin epithelial cells not associated with feathers or FF in the replication and dissemination of infectious virus particles. Scaleless chickens that produce only a few scattered feathers and no sculate scales along the anterior metatarsi were used as a unique model to study the pathogenesis of dermal lesions. Histologic and immunohistochemical analysis revealed that the cutaneous lesions were tumorous as was manifested by massive accumulation of lymphoblasts and extensive activation of meq oncoprotein, the hallmark of MDV oncogenesis, within the skin lesions. Neoplastic cutaneous lesions in the scaleless chickens indicate that feather follicles are not necessary for skin tumor development. Finally, our preliminary data indicate that inoculation with supernatant fluid from homogenized and sonicated skin samples of MDV-infected scaleless chickens induces MD in susceptible birds, suggesting that skin epithelial cells not associated with FF also harbor infectious viral particles.

Expression of a putative tumor-associated surface antigen on normal versus Marek's disease virus-transformed lymphocytes.

Various avian tumor cell lines and normal spleen cells from 3 genetic strains of specific-pathogen-free (SPF) chickens were examined for expression of Marek's disease (MD) tumor-associated surface antigen (MATSA). Two anti-MATSA monoclonal antibodies (RPH 6 and EB 29) and a rabbit anti-MATSA antiserum were used in indirect fluorescent antibody tests, and cells were examined by fluorescence microscopy and with a fluorescence-activated cell sorter (FACS). Less than 5% MATSA-positive cells were observed in 2 non-MD tumor cell lines (LSCC-RP 9 and RECC-CU 60) with RPH 6, but 7-82% positive cells were observed with EB 29 or the rabbit antiserum. Five MD tumor cell lines (MDCC-CU 2, -CU 14, -CU 25, -CU 32, and -CU 41) had 12-72% positive cells detected with one or both monoclonals and 31-99% positive cells detected with the rabbit antiserum. Over 90% of cells in all MD lines were la and T3 positive, while values for the same parameters in LSCC-RP 9 were 100 and 3% and for RECC-CU 60, 48 and 51%, respectively. Evidence for cell-cycle-dependent expression of MATSA on MDCC-CU 2 was obtained from cell sorting experiments with the FACS and from examination of the MATSA-staining characteristics of 3 clones derived from the parent culture. Less than 5% MATSA-positive cells were observed in uncultured spleen cells from SPF chickens or in spleen cells stimulated for 48 hours with concanavalin A or phytohemagglutinin-M. However, with one exception, 10-53% of normal spleen cells were MATSA positive with RPH 6, after stimulation by mitogen for 24 or 48 hours followed by maintenance in conditioned medium (CM) for various times or after culture directly in CM for 3 days. More limited experiments with rabbit anti-MATSA antiserum yielded 55-85% MATSA-positive cells. From 60 to 97% of these MD virus-free, MATSA-positive cells were la-positive; and, in 2 cases, 89 and 90% were T3 positive.

Characteristics of JMV Marek's disease tumor: a nonproductively infected transplantable cell lacking in rescuable Virus.

Cells of the JMV Marek's disease (MD) tumor, originally produced by rapid serial passage of MD lymphoma cells in chickens, were characterized to determine whether they were of host or donor origin and to ascertain certain virus-host cell interrelationships. Differences noted in blood group B surface alloantigens between tumor cells and host lymphocytes indicated a probable nonhost origin (i.e., transplantability) of the tumor. JMV spleen tumors contained predominantly large lymphoblasts bearing MD tumor-associated surface antigen. DNA from JMV tumor cell suspensions hybridized significantly with MD virus cRNA, which indicated that JMV cells contained at least a portion of the MD virus genome. No MD virus was rescued from JMV tumors by techniques suitable for rescue of virus from MD lymphomas. The JMV tumor cells were also devoid of MD virus-specific antigens. These properties differed markedly from those of MD lymphoma cells and make the JMV tumor cell a unique, potentially valuable, tool for further study of oncogenic herpesvirus infection and tumor immunity in the chicken.

A phosphonoacetate-resistant mutant of herpesvirus of turkeys.

A phosphonoacetate (PA)-resistant mutant of the herpesvirus of turkeys (HVT) was isolated and characterized. The mutant of HVT resistant to PA (HVTpa) replicated in duck embryo fibroblast (DEF) culture in media containing 300 microgram PA/ml, whereas the replication of the wild type of HVT (HVTwt) was completely inhibited in DEF culture in media containing 100 microgram PA/ml. The HVTpa was distinct from the HVTwt in plaque morphology, but was indistinguishable antigenically and showed in vitro temperature sensitivity at 41 degrees C (3741 degrees C efficiency of replication was about 5). It replicated poorly in chickens and failed to provide complete protection against challenge with Marek's disease virus (MDV). The HVTpa-induced DNA polymerase had an apparent inhibition constant for PA, an apparent inhibition constant for pyrophosphate, and an apparent Michaells constant for dCTP about 10, 2, and 2.5 times, respectively, greater than the constants for the HVTwt-induced enzyme and was also more thermolabile.

Oncogenesis by Marek's disease herpesvirus in chickens lacking expression of endogenous (gs, chick helper factor, Rous-associated virus-O) and exogenous avian RNA tumor viruses.

Chickens free of exogenous avian leukosis virus (ALV) infection, replicating endogenous ALV (Rous-associated virus-O), gs antigen, and chick helper factor were fully susceptible to induction of Marek's disease (MD) by ALV-free MD viruses. Dual infection with Rous-associated virus-2 and MD virus did not significantly alter the character of the MD lesions. Thus exogenous ALV infection was not requisite for MD virus-induced oncogenesis. Although participation of endogenous RNA tumor virus genes in MD lesion induction could not be excluded, expression of such genes in MD tumors as gs antigen was not established.

Effect of phosphonoacetate on Marek's disease virus replication.

Phosphonoacetate (PA), but not any of its analogues tested, effectively inhibited avian herpesvirus replication and viral DNA synthesis in cell cultures. At 100 mug/ml culture medium, PA completely inhibited the replication of Marek's disease virus (MDV), herpesvirus of turkeys, and owl herpesvirus, but had no measurable effect on normal cell growth. PA also inhibited DNA polymerases induced by these avian viruses. Enzyme inhibition was 50% at a PA concentration of 0.2 mug/ml. At a concentration of 3-6 mug/ml, the compound also effected a 50% inhibition of alpha (maxi) enzyme of the host DNA polymerase. It had no effect on the host beta (mini) enzyme. When administered to chickens, PA did not inhibit the replication of MDV, nor did it prevent the development of lymphoma.

Nature of genetic resistance to Marek's disease in chickens.

Infection of line 6 resistant and line 7 susceptible chickens with Marek's disease virus (MDV) resulted in a depressed phytohemagglutinin (PHA) response and the presence of Marek's disease (MD) tumor-associated surface antigen (MATSA) in the spleens. At 6-10 weeks after infection, recovery in PHA response, diminution in the number of MATSA cells, and the presence of significant anti-MATSA immunity were observed in line 6 but not in line 7 chickens. Both lines had antibody-dependent cell-mediated antiviral immunity, but T-cell-mediated antiviral immunity was detected only in line 6 and the surviving line 7 chickens. Lymphoproliferative lesions were found only in line 7 chickens, an virus titers were significantly higher in line 7 than in line 6 chickens and embryos. Lymphoid organ weights and the number of lymphocytes of line 6 were significantly lower than those of line 7. These data suggests that resistance to MD in line 6 chickens was due to a) a deficiency in the aggregate number of target lymphocytes, b) a restriction in the ability to lymphocytes to nonproductively replicate MDV, and c) the involvement of cellular antiviral and antitumor immune responses.

Taxol-dependent transcriptional activation of IL-8 expression in a subset of human ovarian cancer.

Taxol is important in the treatment of both primary and drug-resistant ovarian cancer. Although Taxol is known to stabilize microtubules and block cell mitosis, the effectiveness of this drug exceeds that of other antimitotic agents, suggesting it may have an additional mode of action. Stimulated by murine macrophage studies indicating cytokine induction by Taxol, we have investigated proinflammatory cytokine expression in a series of cell lines and recent explants of human ovarian cancer. Taxol induced secretion of interleukin (IL) 8 but not IL-6, IL-1alpha, or IL-1beta in 4 of 10 samples. Induction was dependent on transcriptional activation, and, in contrast to murine macrophage studies, was apparently independent of an active lipopolysaccharide signaling pathway. Confluent cultures secreted as much IL-8 as proliferating cells. Taxol did not induce IL-8 in breast carcinoma, endometrial stromal, or T-lymphocyte or monocyte cultures. We propose that the local expression of this chemokine in vivo may elicit a host response similar in effectiveness to that of cytokine gene therapy. These data are the first to suggest that a chemotherapeutic agent may have a direct effect on transcription of cytokine and/or growth factor genes in ovarian cancer, and that this effect may not be restricted to proliferating tumor cells.

Mutational analysis of the proteolytic cleavage site of glycoprotein B (gB) of Marek's disease virus.

The Marek's disease virus (MDV) glycoprotein B (gB) precursor, gp100, is proteolytically cleaved into two disulfide-linked subunits, gp60 and gp49. In the gB homologs of most other herpesviruses, a tetrapeptide, Arg-Xaa-Arg-Arg, is immediately upstream from the predicted cleavage site. We have investigated the specificity of the proteolytic cleavage in gp100 by introducing mutations within its predicted cleavage site (Arg-Leu-Arg-Arg) and expressed these mutants in recombinant fowlpox virus (FPV). The results show that all three Arg residues at the predicted cleavage site play an important role in the specific proteolytic cleavage of gp100. Furthermore, we demonstrated that the cleavage of gp100 is not necessary for transport of gB to the cell surface.

Synthesis and biological evaluation of the 1,5-diarylpyrazole class of cyclooxygenase-2 inhibitors: identification of 4-[5-(4-methylphenyl)-3-(trifluoromethyl)-1H-pyrazol-1-yl]benze nesulfonamide (SC-58635, celecoxib).

A series of sulfonamide-containing 1,5-diarylpyrazole derivatives were prepared and evaluated for their ability to block cyclooxygenase-2 (COX-2) in vitro and in vivo. Extensive structure-activity relationship (SAR) work was carried out within this series, and a number of potent and selective inhibitors of COX-2 were identified. Since an early structural lead (1f, SC-236) exhibited an unacceptably long plasma half-life, a number of pyrazole analogs containing potential metabolic sites were evaluated further in vivo in an effort to identify compounds with acceptable pharmacokinetic profiles. This work led to the identification of 1i (4-[5-(4-methylphenyl)-3-(trifluoromethyl)- H-pyrazol-1-yl]benzenesulfonamide, SC-58635, celecoxib), which is currently in phase III clinical trials for the treatment of rheumatoid arthritis and osteoarthritis.

Identification and characterization of a Marek's disease virus gene encoding DNA polymerase.

DNA sequence analysis revealed a gene encoding the Marek's disease virus (MDV) DNA polymerase (pol) within the BamHI-E fragment of the long unique region of the virus genome. Identification is based on an extensive amino acid homology between the MDV open reading frame and the DNA pol (UL30) of the herpes simplex virus. We describe here a 3540-base-pair fragment of the MDV DNA encoding 1180 amino acids with a M(r) of 133,920 daltons as the viral DNA pol gene, with the analysis of transcription and translation. In Northern blot hybridization, a transcript of 4.0 kb was detected in GA-MDV-infected duck embryo fibroblast (DEF) cells. An antiserum was generated in rabbit using TryE-pol fusion protein expressed in E. coli. This antiserum specifically immunoprecipitated a protein of 135 kD from lysates of MDV-GA-infected DEF cells. MDV DNA pol showed extensive homology to five distantly related herpesviruses: equine herpesvirus (EHV), varicella-zoster virus (VZV), herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV), and human cytomegalovirus (HCMV). Comparison of amino acid sequences among the herpesviruses highlights nine highly conserved regions. Three of the conserved regions are in the N-terminus in the 3'-5' exonuclease domains and the remaining six are in the C-terminus in the catalytic domains. The predicted structural characters are in good agreement with the published data on a number of human herpesvirus DNA pol. The identification of MDV DNA pol gene may lead to a better understanding of MDV replication.

Clinical panel assessment of photodamaged skin treated with isotretinoin using photographs.

BACKGROUND AND DESIGN: Evaluation of the treatment of photodamaged skin requires adequate efficacy criteria. This study tested the ability of five independent dermatologists to distinguish the effect of topical treatment with isotretinoin cream (0.05% for 3 months, then 0.1% for 6 months) in 326 patients compared with vehicle for 9 months in 325 patients using high-quality, reproducible photographic slides. Panelists were blinded to the patient's identity, treatment group, and time of the photograph (baseline or end of treatment). A computer randomly projected the baseline photograph to one side of a split screen and the end-of-treatment photograph to the other. OBSERVATIONS: Isotretinoin was significantly better than vehicle for overall appearance, fine wrinkles, and discrete pigmentation by multivariate analysis of the combined results for all panelists. Univariate analysis for each panelist also indicated statistically significant superiority of isotretinoin over vehicle for overall appearance (four panelists), fine wrinkles (five panelists), and discrete pigmentation (three panelists). CONCLUSION: The clinical panel detected significantly better improvement in photodamaged-skin treated with isotretinoin than in such skin treated with vehicle. The panel provided an independent assessment of the effects of treatment uninfluenced by physical findings during treatment or information provided by the patients treated.

Cytotoxic T lymphocyte response in chickens immunized with a recombinant fowlpox virus expressing Marek's disease herpesvirus glycoprotein B.

Previously, we demonstrated that cytotoxic T lymphocytes (CTLs) from MHC: B19B19 and MHC: B21B21 chickens inoculated with a non-oncogenic Marek's disease virus (MDV) vaccine strain, SB-1/12 can lyse syngeneic reticuloendotheliosis virus (REV)-transformed cell lines expressing MDV pp38 or gB genes. In this study, we report the characterization of MDV gB-specific CTLs in chickens immunized with recombinant fowlpox virus expressing MDV gB gene (rFPV-gB). Spleen cells from rFPV-gB inoculated chickens (MHC: B19B19), depleted for CD4+, CD8+, TCR gamma delta+, TCR alpha beta 1+ or TCR alpha beta 2+ cells were used as effector cells in chromium release assays. Effector cells depleted of CD8+ or TCR alpha beta 1+, but not CD4+, TCR gamma delta+ or TCR alpha beta 2+ markedly reduced the percentage of specific release (%SR). Compared to the %SR caused by the SB-1/12-sensitized CTLs, the %SR caused by rFPV-gB-sensitized CTLs was low, but statistically significant. This is a first report on the induction of MDV gB-specific CD8+ CTLs in chickens immunized with rFPV-gB vaccine.

Chicken lymphocyte stimulation by mitogens: a microassay with whole-blood cultures.

A micromethod is described that uses whole blood for studying mitogen stimulation of chicken lymphocytes. Procedures critical for obtaining a stimulatory response up to 200 times that of unstimulated control cultures include: 1) use of no more than 10 microliter of whole blood per culture; 2) incubation at 41 C for 72 hours in 0.2 ml of medium RPMI 1640 containing 100 microgram of stock phytohemagglutinin-P and 3) pulse labeling for 8 hours with 5-[125I] iodo-2'-deoxyruidine. The method is easy, rapid, and suitable for sequential studies of pathogenesis of disease in poultry.