A B7-1-transfected human melanoma line stimulates proliferation and cytotoxicity of autologous and allogeneic lymphocytes

B7 co-stimulation is necessary to activate resting T cells upon antigen recognition by the T cell receptor. To see whether expression of B7 may render human melanoma cells able to stimulate T cells, a cloned melanoma line (Me1B6), which did not express B7-1, was transfected with the human B7-1 gene. In proliferation assays, B7-1 transfected cells (Me1B6/B7) showed greater stimulatory activity of allogeneic and autologous peripheral blood lymphocytes (PBL) compared to parental, non-transfected tumor cells. This effect was also seen when allogeneic CD8⁺ and CD4⁺ subpopulations were used as effectors. In these studies, activation of lymphocytes was B7-1-dependent and HLA classes I and II mediated. The higher proliferation correlated with an increased lytic activity by PBL stimulated with B7-1⁺ tumor cells against the untransfected Me1B6. Furthermore, PBL from a metastatic melanoma patient stimulated by Me1B6/B7 developed an higher lytic activity not only against Me1B6 but also against their autologous, B7-1^? tumor. Finally, after Me1B6/B7 stimulation, PBL released interleukin (IL)-2 and interferon-γ, but not IL-4, suggesting a Th1-mediated response. These data support the use of B7-1 transfected melanoma cells in the therapeutic vaccination of melanoma patients.     

The frequency of chromosome anomalies in human preimplantation embryos after in-vitro fertilization

Previous studies have reported chromosome aberrations in humanpre-embryos after in-vitro fertilization (IVF). Although thereason for these abnormalities is not clear, there is evidencethat they can arise during gametogenesis, fertilization or cleavage.The present study has examined further the incidence of chromosomeabnormalities in human pre-embryos after IVF, using oocytesrecovered from normal volunteer women and from women undergoinginfertility treatment in an embryo-replacement programme. Chromosomepreparations were performed for 75 pre-embryos. Of these 35(47%) gave at least one metaphase in which analysis was possible.The overall incidence of abnormal pre-embryos was 40% (14/35).The absolute frequency of aberrations was 9% for trisomies,3% for polyploidies, 26% for structural anomalies and 3% forhypodiploidies. Five pre-embryos were found to be mosaics, threeof which had each one trisomic metaphase. In five of the pre-embryosmultiple anomalies were found. In 13 of the 14 abnormal pre-embryosthe aberrations were found in only one metaphase. The presentstudy demonstrates that trisomic mosaicism may not be a rareevent in human pre-embryos. Further evidence is provided thatmitotic non-disjunction is important for the production of aberrationsin human pre-embryos     

Possible pathways of circulation of human endogenous retrovirus similar to mouse mammary tumor virus

It is shown that polypeptides which are immunologically related to gp52 mammary tumor virus are found in T and B peripheral blood lymphocytes in all breast cancer patients, in children with B-cell lymphosarcomas, and in B lymphocytes of some healthy donors. These proteins are not found in patients with tumors of other sites. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 11, pp.554–556, November, 1995 Presented by Yu. N. Solov'ev, Member of the Russian Academy of Medical Sciences     

Primary choriocarcinoma and human chorionic gonadotrophin‐producing giant cell carcinoma of the lung: are they independent entities?

AIMS: Human chorionic gonadotrophin (hCG) is a useful marker for chorionic proliferative disorders, such as choriocarcinoma. Although hCG synthesis in lung cancers is frequent, primary pulmonary choriocarcinoma (PCC) is rare. To clarify the differences between primary choriocarcinoma and hCG-producing giant cell carcinoma (GCC) of the lung, we compared the clinicopathological and immunohistochemical findings of these tumours. METHODS AND RESULTS: Three patients, one with PCC and two with hCG-producing GCC, were included in this study. They were all middle-aged men and habitual smokers. The growth of these tumours and the progression of the clinical courses were extremely rapid, and the patients all died within 8 months after the pulmonary tumours were found. Haemorrhagic appearance was a common macroscopic feature of the specimens obtained. Microscopically, both types of tumours mainly consisted of atypical polygonal cells. While PCC contained many syncytial trophoblast-like multinucleated cells that had strong immunoreactivity for anti-hCG, such cells were relatively few in hCG-producing GCC. These histological and immunohistochemical findings reflected the serum test result for hCG, which was higher in the case of PCC. CONCLUSIONS: There are a few differences between PCC and hCG-producing GCC, as described above. Reliable distinction between them seems to be difficult for pathologists and worthless for clinicians.     

Genomic characterization of KIR2DL4 in families and unrelated individuals reveals extensive diversity in exon and intron sequences including a common frameshift variation occurring in several alleles

The KIR2DL4 gene including a portion of exon 1 through exon 9 was sequenced from two families and eight cell lines from the International Histocompatibility Workshop (IHWS). Two known alleles and eight variants were detected. Overall, there were five synonymous and three non-synonymous changes when the variants were compared to the coding sequences of the most closely related known alleles plus a common frameshift change in five of the variant alleles. Alignment of the new variants with all known alleles showed that the regions encoding the extracellular region and the cytoplasmic tail were the most polymorphic. Two non-synonymous changes, P146H and L161V, occurred in an extracellular immunoglobulin-like domain. Five of the eight variants had a single adenine deletion in the exon encoding the transmembrane region, potentially resulting in a truncated protein lacking the cytoplasmic tail. The distribution of the deletion variant among many KIR2DL4 alleles may explain the high frequency of this variation in the population. Four of the eight consanguineous IHWS cell lines were found to be heterozygous for KIR2DL4 carrying two alleles that differed from one another by a few nucleotide substitutions. Analysis of intron sequences in the families revealed the nature and distribution of interspersed repeat elements which comprise 46% of the KIR2DL4 nucleotide sequence and consist of 12 elements including six SINEs (13.73% of the total length), one LINE (12.41%), and five LTR elements (19.51%). The results revealed the presence of extensive diversity in the KIR2DL4 gene. This is the first extensive report providing both exon and intron data in related individuals.     

Cloned cellular reagents to define antigens encoded between HLA-DR and glyoxylase

Primed lymphocyte typing reagents have been used to define antigens encoded by genes of a locus (loci) mapping between HLA-DR and glyoxalase I. This locus, which we shall refer to as the third locus of the HLA-D region, has been variously referred to as D beta, PL beta, PL3, and SB. Generating discriminatory primed lymphocyte typing reagents which can be used to define these antigens, however, has been extremely difficult. Donors of responding and stimulating cells for the priming combinations have usually been matched not only for the DR, D, and MB/MT antigens but also for the HLA-A, -B, and -C antigens. Even under these very restricted conditions, not all bulk primed lymphocyte typing reagents that are generated are discriminatory enough to be useful for antigen definition. We have derived "clones" from bulk priming combinations in which stimulator and responder differed for known antigens of this third locus. Even though the bulk reagents that were prepared did not provide discriminatory results, approximately 7-12% of the clones derived from the bulk priming combination proved to be highly discriminatory. We have been able to obtain these results with regard to all three antigens of the third locus so far evaluated. The very ease of screening clones and deriving discriminatory reagents, as compared with screening responder-stimulator combinations, allows the ready derivation of cellular reagents that define the antigens of this third locus.     

Morphine-6beta-glucuronide modulates the expression of inducible nitric oxide synthase

The immunomodulatory effects of morphine are well established; however, suprisingly little is known about the immunomodulatory properties of the major metabolites of morphine. The present study tests the hypothesis that expression of inducible nitric oxide synthase (iNOS) is modulated by the administration of the morphine metabolite, morphine-6-glucuronide. The initial study using rats shows that morphine-6-glucuronide administration (0, 1.0, 3.163, 10 mg/kg s.c.) results in a pronounced reduction in lipopolysaccharide (LPS)-induced expression of iNOS (inducible nitricoxide synthease) in spleen, lung, and liver tissue as measured by western blotting. Morphine-6-glucuronide also produces a reduction in the level of plasma nitrite/nitrate, the more stable end-product of nitric oxide degradation. In a subsequent study, administration of the opioid receptor antagonist, naltrexone (0.1 mg/kg) prior to the injection of morphine-6-glucuronide (10 mg/kg) blocks the morphine-6-glucuronide induced reduction of iNOS expression and plasma nitrite/nitrite levels indicating that the effect is mediated via the opioid-receptor. This study provides the first evidence that morphine-6-glucuronide alters the expression of iNOS.     

Effects of suramin on metastatic ability,proliferation, and production of urokinase-type plasminogen activator and plasminogen activator inhibitor type 2 in human renal cell carcinoma cell line SN12C-PM6

Effects of suramin, a polysulfonated naphthylurea compound, on metastatic ability, proliferation, and production of plasminogen activators and plasminogen activator inhibitors were studied using the highly metastatic human renal cell carcinoma cell line, SN12C-PM6. After renal subscapular implantation of tumor cells in nude mice, suramin significantly inhibited metastasis of tumor cells to the lungs and liver. In vitro growth of tumour cells was inhibited by suramin in a dose-dependent manner, at relatively low doses (ID₅₀ = 105 µg/ml). Plasminogen activator inhibitor type 2 (PAI-2) production by tumor cells was enhanced by suramin (100 µg/ml), whereas urokinase-type plasminogen activator (uPA) production was suppressed. Thus, the increase in PAI-2 and the decrease in uPA production correlated with the inhibitory effects on tumour growth and metastasis by suramin. Therefore suramin may be beneficial for the treatment of patients with an early stage of renal cancer with potential risk of metastasis.     

The thymus as primary site for antigen-specific T suppressor cells in neonatally induced tolerance to bovine serum albumin

The ontogeny of antigen-specific T suppressor cells in thymus and spleen was analyzed in CBA/Ca mice which were rendered tolerant as neonates by subimmunogenic doses of bovine serum albumin (low-zone tolerance). Activity of T suppressor cells from those mice was assessed by an assay in which spleen cells from animals primed with fluorescein-conjugated human gamma globulin can be stimulated in vitro to produce IgG anti-fluorescein antibodies when cultured in the presence of fluorescein-conjugated bovine serum albumin. Carrier-specific T suppressor cells appear first in the thymus (day 10), and much later (day 30) in the spleen. The data are discussed in connection with the possible role of T suppressor cells during induction of tolerance in newborn mice.