Selection of cytotoxic T lymphocytes against autologous human melanoma from lymph nodes with metastatic melanoma using repeatedin vitro sensitization

Our goal was to determine the cytotoxic activity of effector cells in lymph nodes with metastatic melanoma. Lymphocytes contained within tumor cells from metastatic lymph nodes of two patients were allowed to proliferate in recombinant IL-2 (rIL-2, 100-1,000 units/ml) after 14–21 days of culture. Each set of lymphocytes showed cytotoxicity against autologous melanoma (AM, mean 72%) at effector to target ratio of 201 and K562 cells (mean 60%) using 4-h chromium-51 release assay. Using unlabeled AM and K562, each AM could partially block the activity against K562, but K562 could not block the activity against AM. These activated lymphocytes underwentin vitro sensitization (IVS) with irradiated AM cells and rIL-2 at 2-week intervals. After repeated IVS over about 50 days, each patient's lymphocytes showed cytotoxicity against AM (mean 54%) but not K562 (mean 5%,P < 0.001). These results indicate that different cytotoxic effector cells were present in the early and late phase of lymphocyte tumor culture. Repeated IVS resulted in the selection of specific cytotoxic T lymphocytes. Cold target inhibition assay demonstrated that melanoma cells contained common and individual AM-associated antigen in addition to K562-associated antigens.This work was supported by Biomedical Research Support Grant of the University of Arizona (no. 2S07 RR05675-20), the Elsa U. Pardee Foundation Grant, partly by the Arizona Chronic Disease Research Commission and partly by CA23074 from the National Institutes of Health, Bethesda, 20892, U.S.A.Recipient of the American Cancer Society Clinical Oncology Career Award, 1987–90.     

Viewer-centred and object-centred coding of heads in the macaque temporal cortex

Summary An investigation was made into the sensitivity of cells in the macaque superior temporal sulcus (STS) to the sight of different perspective views of the head. This allowed assessment of (a) whether coding was viewer-centred (view specific) or object-centred (view invariant) and (b) whether viewer-centred cells were preferentially tuned to characteristic views of the head. The majority of cells (110) were found to be viewer-centred and exhibited unimodal tuning to one view. 5 cells displayed object-centred coding responding equally to all views of the head. A further 5 cells showed mixed properties, responding to all views of the head but also discriminating between views. 6 out of 56 viewer and object-centred cells exhibited selectivity for face identity or species. Tuning to view varied in sharpness. For most (54/73) cells the angle of perspective rotation reducing response to half maximal was 45–70° but for 19/73 it was >90°. More cells were optimally tuned to characteristic views of the head (the full face or profile) than to other views. Some cells were, however, found tuned to intermediate views throughout the full 360 degree range. This coding of many distinct head views may have a role in the analysis of social signals based on the interpretation of the direction of other individuals' attention.     

Postextrasystolic potentiation does not distinguish ischaemic from stunned myocardium

Myocardial function is impaired by ischaemia, and it remains depressed during reperfusion following short periods of ischaemia (stunned myocardium). We tested whether ischaemic and reperfusion dysfunction, in particular the time course of its recovery, can be distinguished by postextrasystolic potentiation (PESP). In eight open-chest dogs, posterior systolic wall thickening (sonomicrometry) was reduced by graded occlusion of the left circumflex coronary artery (LCX) from 17.4±6.8% (SD) during control conditions to 10.7±1.3% (mild ischaemic dysfunction), 7.2±2.3% (moderate ischaemic dysfunction), 3.6±1.4% (severe ischaemic dysfunction), and -4.4±3.6% (complete coronary occlusion). Extrasystoles with constant prematurity and a fully compensated postextrasystolic interval were induced after at least 4 min steady-state ischaemia. After each ischaemic period full recovery of posterior systolic wall thickening was assured. During 8 h of reperfusion following a 15-min LCX occlusion, extrasystoles were induced when posterior systolic wall thickening was comparable to one degree of the preceding ischaemic dysfunction. The increases in posterior systolic wall thickening induced by PESP were 10.5±5.8% during control conditions, during ischaemia they were 11.5±3.5% (mild dysfunction), 12.3±4.6% (moderate dysfunction), 12.6±4.1% (severe dysfunction) and 10.4±4.4% (complete coronary occlusion), and during reperfusion they were 12.8±8.2% (severe dysfunction), 13.0±9.7% (moderate dysfunction) and 10.7±2.2% (mild dysfunction). These increments in systolic wall thickening as well as those in ejection thickening were not significantly different. PESP can thus not distinguish between ischaemic and reperfusion dysfunction nor between different degrees of myocardial dysfunction.This study was supported by the Deutsche Forschungsge-meinschaft (He 1320/3-2). cand. med. S. Schäfer was involved in some of these experiments and presented part of the data at the 56th Annual Meeting of the Deutsche Gesellschaft für Herz- und Kreislaufforschung in Mannheim (Z Kardiol 79 [Suppl 1]: 24,1990). Part of the data were also presented at the 11th Congress of the European Society of Cardiology in Nice (Eur Heart J 10 [Suppl]: 242, 1989) and at the 73rd Annual Meeting of the Federation of American Societies for Experimental Biology in New Orleans (FASEB J 3: A841, 1989)     

Differences in extent of genetic introgression between sympatric Culex pipiens and Culex quinquefasciatus (Diptera: Culicidae) in California and South Africa

Comparisons of five morphological characters, 12 enzyme electrophoresis profiles, and Wolbachia pipientis infection rates were used to characterize populations of members of the Culex pipiens L. complex in California and South Africa. In South Africa, male phallosome DV/D ratio, male maxillary palp index, branching of siphonal seta 1a, the enzyme locus Mdhp-1, and W. pipientis infection rates proved highly diagnostic for separating Culex quinquefasciatus from Cx. pipiens phenotypes. In Johannesburg, where sympatric members of the Cx. pipiens complex were analyzed as one population, a significant Wahlund Effect was observed in the enzyme loci such as Ao, 6-Pgdh, Mdh-2, and Pgm. In California, all populations of the Cx. pipiens complex were in Hardy Weinberg equilibrium at all polymorphic enzyme loci examined. Additionally, in California, all populations had similar W. pipientis infection rates and appeared morphologically identical (except for DV/D ratio, in extreme north and south). These findings indicate that in South Africa, Cx. pipiens and Cx. quinquefasciatus remain as genetically distinct populations and behave as separate species. Conversely, in California, there is considerable genetic introgression between Cx. pipiens and Cx. quinquefasciatus, and they behave as a single species.     

A sensitive bioassay for chicken interleukin-18 based on the inducible release of preformed interferon-gamma

Conventional tests for measuring the biological activity of chicken interleukin (IL)-18 require primary chicken spleen cells. We now describe a sensitive bioassay that is based on interleukin-18-induced release of interferon (IFN)-gamma by a permanent chicken cell line. In B19-2D8 cells, cytoplasmically stored interferon-gamma is quickly secreted in response to interleukin-18 exposure.     

Cytogenetic,spectral karyotyping,fluorescence in situ hybridization,and comparative genomic hybridization characterization of two new secondary leukemia cell lines with 5q deletions,and MYC and MLL amplification

Cytogenetic studies of patients with therapy-induced acute myeloid leukemia (t-AML) have demonstrated whole chromosome loss or q-arm deletion of chromosomes 5 and/or 7 in a majority of cases. We have established two cell lines, SAML-1 and SAML-2, from two patients who developed t-AML after radiation and chemotherapy for Hodgkin disease. In both cases, the leukemia cells contained 5q deletions. SAML-1 has 58 chromosomes and numerous abnormalities, including der(1)(1qter-->1p22::5q31-->5qter), der(5)(5pter-->5q22::1p22-->1pter), +8, der(13)i(13)(q10)del(13)(q11q14.1), and t(10;11). Fluorescence in situ hybridization (FISH) with unique sequence probes for the 5q31 region showed loss of IL4, IL5, IRF1, and IL3, and translocation of IL9, DS5S89, EGR1, and CSFIR to 1p. SAML-2 has 45 chromosomes, del(5)(q11.2q31) with a t(12;13)ins(12;5), leading to the proximity of IRF1 and RB1, and complex translocations of chromosomes 8 and 11, resulting in amplification of MYC and MLL. Comparative genomic hybridization and spectral karyotyping were consistent with the G-banding karyotype and FISH analyses. Because a potential tumor suppressor(s) in the 5q31 region has yet to be identified, these cell lines should prove useful in the study of the mechanisms leading to the development of t-AML.     

High genetic diversity of HIV-1 strains in Chad,West Central Africa

The genetic diversity of HIV-1 strains in Chad was documented with a total of 107 samples from patients attending the general hospital in N'Djamena, the capital city of Chad. The genetic subtypes were identified in the V3-V5 env and p24 gag regions by sequence and phylogenetic tree analyses. Of the 107 strains, 78 had the same subtype/CRF designation between env and gag. Four subtypes and three CRFs were found to cocirculate: subtype A, 20.5%; subtype D, 18.7%; CRF02_AG, 13.1%; CRF11_cpx, 13.1%; subtype G, 3.7%; CRF01_AE, 2.8%; and subtype F1, 0.9%. The remaining 29 strains (27%) had discordant subtypes or CRF designations between env and gag; in 15 of these 29 strains, a CRF was involved in the recombination event, and 10 were subtype G in gag and subtype A in env, forming a separate subcluster within subtypes G and A. Subtype D strains represent almost 20% of the HIV-1 strains circulating in Chad and form a separate subcluster in gag and env. Nearly full-length genome sequencing for two such strains (99TCD-MN011 and 99TCD-MN012) revealed that they represent nonrecombinant subtype D variants. Compared with neighboring countries, the genetic subtype distribution of HIV-1 strains in Chad is unique for several reasons: lower prevalence of CRF02, high prevalence of CRF11 and subtype D, and absence of CRF06. These data clearly show that subtype distribution is very heterogeneous in Africa, probably the result of different founder effects.     

Treatment plan modification using voxel-based weighting factors/dose prescription

Under various clinical situations, it is desirable to modify the original treatment plan to better suit the clinical goals. In this work, a method to help physicians modify treatment plans based on their clinical preferences is proposed. The method uses a weighted quadratic dose objective function. The commonly used organ-/ROI-based weighting factors are expanded to a set of voxel-based weighting factors in order to obtain greater flexibility in treatment plan modification. Two different but equivalent modification schemes based on Rustem's quadratic programming algorithms--modification of a weighting matrix and modification of prescribed doses--are presented. Case studies demonstrated the effectiveness of the two methods with regard to their capability to fine-tune treatment plans.     

Comparative genomic hybridization analysis of hepatoblastoma reveals high frequency of X-chromosome gains and similarities between epithelial and stromal components

Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm.