Simian immunodeficiency virus (SIV)-specific CTL in cerebrospinal fluid and brains of SIV-infected rhesus macaques

Simian immunodeficiency virus (SIV)-specific CD8+ CTL were isolated from blood, cerebrospinal fluid, and brains of rhesus macaques infected i.v. with SIV. CTL were found as early as 1 wk postinfection and their appearance correlated with a decrease of viral Ag (p27) found in the blood. CTL isolated from cerebrospinal fluid and/or brain often recognized different viral proteins than CTL isolated from blood, suggesting either a unique migratory pattern to the central nervous system or a difference in activation/retention of lymphocytes in these compartments.     

CD28-induced cytokine production and proliferation by thymocytes are differentially regulated by the p59fyn tyrosine kinase

CD28 is a 44-kDa homodimeric receptor that is expressed on the majority of T cells. Engagement of the CD28 receptor by soluble anti-CD28 mAb in conjunction with phorbol ester (PMA) induces the production of cytokines and the proliferation of resting T cells via signal transduction pathways independent of the TCR. Evidence is provided herein that CD28 signals leading to cytokine production do not require the p59fyn (Fyn) tyrosine kinase, whereas CD28-mediated proliferation is dependent on the presence of the Fyn kinase in thymic, but not lymph node, cells. The defect in proliferation is not due to failure of IL-2R signaling, since addition of high concentrations of exogenous IL-2 can overcome the proliferative defect. Analysis of CD28-directed induction of the IL-2R alpha (CD25)-chain, which confers high affinity binding to IL-2, showed that Fyn-deficient thymocytes, but not lymph node cells, failed to up-regulate CD25 expression following anti-CD28 and PMA stimulation. Thus, the Fyn tyrosine kinase is critically required for thymic CD28-mediated CD25 expression and proliferation but not for CD28-mediated cytokine production.     

Stage T1-2 prostate cancer: a multivariate analysis of factors affecting biochemical and clinical failures after radical prostatectomy

PURPOSE: Prostate-specific antigen (PSA) is extensively used in case selection and outcome evaluation after treatment of clinically localized prostate cancer. Careful case selection can have a profound impact on pathologic findings and ultimate outcome. In addition, salvage treatment is frequently initiated at the time of biochemical relapse rather than clinical recurrence. Consequently, patterns of failure can be significantly altered compared to previous times when PSA was not available. To better understand the impact of PSA on pathologic findings, outcome, and salvage treatment, we reviewed our experience in the PSA era with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. METHODS AND MATERIALS: Between 1987 and 1993, 423 cases could be identified with clinical Stage T1-2 prostate cancer treated with radical prostatectomy. The distribution of cases by pretreatment PSA levels was as follows: < or = 4 ng/ml (18%), 4-10 ng/ml (42%), 10-20 ng/ml (21%), > 20 ng/ml (14%), and unknown (5%). The median pretreatment PSA level for the entire group was 8.0 ng/ml. Sixteen patients received adjuvant or neoadjuvant androgen suppression and 13 received postoperative radiotherapy. Only 31 patients (7%) had pathologically positive pelvic lymph nodes. The overall margin involvement rate was 46%. Fifty-three percent of patients had surgical Gleason scores > or = 7, and 65% had extracapsular extension. The median follow-up time was 41 months. RESULTS: The projected overall survival at 7 years after surgery was 90%. The 5-year clinical relapse-free survival rate was 84%. At 5 years, the local control and distant failure rates were 92% and 91%, respectively. Biochemical relapse was defined as a detectable or rising PSA level after prostatectomy. The 5-year biochemical relapse-free survival (bRFS) rate was 59%. The 5-year RFS was 88% in patients with preoperative PSA levels < or = 4, 62% for 4-10, 48% for 10-20, and 31% for > 20. Combining the two independent preoperative variables, iPSA and biopsy GS (bGS), two risks groups were defined: low risk [initial PSA (iPSA) levels < or = 10.0 and bGS < or = 6] and high risk (iPSA levels > 10.0 ng/ml or bGS > or = 7). The 5-year bRFS rate for the low-risk cases was 81% vs. 40% for high-risk cases (p < 0.001). On multivariate analysis, three factors independently predicted biochemical relapse: iPSA levels (p = 0.005), Gleason score from the surgical specimen (sGS) (p = 0.002), and positive surgical margins (p < or = 0.001). The 5-year bRFS rates for margin positive vs. margin negative patients were 37% vs. 78%, respectively. The 5-year bRFS rates for GS > or = 7 vs. GS > or = 6 were 42% vs. 80%, respectively. All clinical relapses were accompanied by a rise in PSA. In patients who manifested biochemical failure followed by a clinical failure, the median interval between the PSA rise and clinical failure was 19 months (range 7-71). Margin involvement was the only independent predictor of local failure (p = 0.019). The 5-year local failure-free survival for negative margin cases was 96% vs. 87% for positive margin cases (p = 0.012). Lymph node (LN) involvement and high-risk group were the two independent predictors of distant failure. The 5-year distant failure-free survival for negative LN cases was 94% vs. 67% for positive LN cases (p < 0.001). The 5-year distant failure-free survival for low-risk cases was 97% vs. 85% for high-risk cases (p = 0.005). For the 124 patients failing biochemically, 85 were observed and 39 were treated either with radiation or androgen deprivation. With a median follow-up of 32 months, the clinical disease relapse-free survival was 79% for the treated patients vs. only 32% for the patients observed (p < 0.001). CONCLUSION: Pretreatment PSA is the most potent clinical factor independently predicting biochemical relapse, thereby allowing markedly better case selection. Achieving negative margins, even in relatively advanced disease, provides excellent lon     

Detection of serum interferon-alpha by dissociation-enhanced lanthanide fluoroimmunoassay. Studies of patients with acute viral and bacterial infections

A sensitive dissociation-enhanced lanthanide fluoroimmunoassay (DELFIA) was evaluated for ability to detect interferon-alpha (IFN-alpha) in serum of patients with acute infectious disease of less than one week's duration and a fever of > 38 degrees C. None of 36 patients with confirmed or probable bacterial disease was IFN-alpha positive. In contrast, 13/26 patients with viral infections had detectable levels of IFN-alpha in serum, all clearly positive (> or = 10 U/ml). The IFN-alpha positive serum samples were obtained early after onset of clinical disease, after a mean of 2.4 days. The IFN-alpha positive samples were obtained from 10 of the 12 patients with influenza or flu-like infection, and 3 of the 5 patients with varicella or herpes zoster. The IFN-alpha negative patients with viral disease (n = 9) included five patients with mononucleosis. The DELFIA should be useful in further studies of the value of IFN-alpha determinations in the identification of acute viral infections.     

Heat shock cognate protein 71-associated peptides function as an epitope for Toxoplasma gondii-specific CD4+ CTL

HLA-DR-restricted CD4+ cytotoxic T-lymphocyte (CTL) lines specific for Toxoplasma gondii (T. gondii)-infected melanoma cells have been established from peripheral blood lymphocytes (PBLs) of a patient with chronic toxoplasmosis. The role of heat shock cognate protein (HSC) 71 in antigen (Ag) processing and presentation of T. gondii-infected melanoma cells to these CD4+ CTL lines was investigated. A human melanoma cell line (P36) pulsed with T. gondii-infected P36 cell-derived HSC71 was lysed by a T. gondii-specific CD4+ CTL line (Tx-HSC-1). The Tx-HSC-1 also killed T. gondii-infected P36 cells. The lytic activity of Tx-HSC-1 against P36 cells pulsed with T. gondii-infected P36 cell-derived HSC71 was inhibited by monoclonal antibodies (mAbs) against HSC71. Anti-human leukocyte antigen (HLA)-DR mAb also partially blocked the lytic activity, whereas anti-HLA-A,B,C mAb did not block the lytic activity. In addition, a flow cytometric analysis with these specific mAbs against HSC71 showed HSC71 to be expressed on the cell surface of T. gondii-infected P36 cells as well as uninfected P36 cells. These data indicate that HSC71 molecules are expressed on human melanoma cell line P36, and that HSC71 may play a potential role in Ag presentation and processing of T. gondii-infected P36 cells to CD4+ CTL.     

The safety and efficacy of transcatheter arterial chemoembolization in the treatment of patients with hepatocellular carcinoma and main portal vein obstruction. A prospective controlled study

BACKGROUND: Transcatheter arterial chemoembolization (TACE) has been contra-indicated for the treatment of patients with hepatocellular carcinoma (HCC) and main portal vein (MPV) obstruction because of the potential risk of hepatic insufficiency resulting from ischemia after TACE. The current controlled study was undertaken to assess the safety, efficacy, and predictive factors of favorable response to TACE in patients with HCC and MPV obstruction with good hepatic function and adequate collateral circulation around the MPV. METHODS: Of a total of 47 patients, 31 were treated with TACE, and 16 who declined the procedures were untreated controls. Thirty-six patients (77%) had diffuse-type HCC and 11 (23%) had nodular-type HCC. During the first week after TACE immediate postprocedural complications were evaluated, and the development of hepatic insufficiency as a late complication was assessed at the end of the fourth week. The cumulative survival rate was estimated by the Kaplan-Meier method, and predictors of better prognosis were obtained by univariate and multivariate analyses. RESULTS: Although no patients showed clinical evidence of hepatic insufficiency as an immediate complication, transient fever and abdominal pain were common. Progressive hepatic insufficiency developed at the fourth week; however, there was no difference between the treated and untreated groups. The survival time of treated patients was statistically no longer than that of untreated patients. In the univariate analysis, tumor type and size, the pattern of iodized oil uptake in the tumor, and the presence of iodized oil uptake in the tumor thrombi at the MPV significantly influenced the prognosis. Tumor type, whether treated or not, was the most important prognostic factor patients with nodular-type HCC had significantly longer survival time (median, 11 months) than those with diffuse-type HCC (median, 4 months). Regarding the efficacy of TACE, there was no statistical difference in survival between treated and untreated diffuse-type HCC patients. In comparison, with nodular-type HCC it seemed that survival time was longer for TACE-treated patients (median, 30 months) than for untreated patients (median, 7 months). CONCLUSIONS: TACE may be a safe modality for the treatment of patients with HCC and MPV obstruction, provided that the patients have good hepatic function and collateral circulation around the MPV. However, TACE was not efficacious in the treatment of diffuse-type HCC. The authors recommend TACE for treating nodular-type HCC because of the potential benefit of prolonged survival.     

Random shuttle mutagenesis: gonococcal mutants deficient in pilin antigenic variation

Shuttle mutagenesis has been adapted to randomly mutate the genome of Neisseria gonorrhoeae (gonococcus; Gc). A size-restricted plasmid library of Gc strain FA1090 was mutated with the mini-transposon mTnEGNS. Radomness was tested by checking for transposon insertion bias between vector and insert DNA, Gc transformation efficiency of individual mutated clones, and representation of unique clones before and after Gc transformation with a mutated pool of DNA. Mutants created by random shuttle mutagenesis were screened, using a colony-based polymerase chain reaction assay, for the ability to undergo pilin antigenic variation. Out of 8,064 mutants screened, 22 unique transposon insertion mutants were found to be antigenic variation deficient (Avd). The Avd mutants were separated into five types according to recombination defect-associated phenotypes, including colony growth, natural DNA transformation competence, and repair of DNA damage caused by ultraviolet radiation.