Publication of clinical trials: accountability and accessibility.

Publication of findings from clinical trials is a necessary step in the research continuum, to provide a record of the work done, convey information to the community, and support translation of research into clinical practice. Systematic reviews of randomized controlled trials are now widely regarded as the highest level of evidence in determining the effect of an intervention on an outcome. They largely depend on internationally accessible, published reports of all trials undertaken. Investigators and their institutions or organizations have responsibility for reporting their clinical trials accurately and completely, including disclosure of potential conflicts of interest. To ensure evidence-based health care, issues relating to accessibility and accountability of clinical trial results require immediate action.

Second-trimester maternal serum progesterone levels in Turner syndrome with and without hydrops and in trisomy 18.

Placental proteins, such as inhibin A and hCG and its subunits, as well as the placental steroid progesterone, are elevated in second-trimester maternal serum from cases of fetal Down syndrome. Since different cellular mechanisms are required for protein versus steroid synthesis and secretion, these data suggest that a generalized placental hypersecretory phenomenon is associated with Down syndrome. Inhibin A and hCG are also elevated in cases of Turner syndrome with hydrops, and are reduced in cases of Turner syndrome without hydrops and in trisomy 18. The objective of the present study was to determine maternal serum levels of the placental steroid progesterone in cases of Turner syndrome and trisomy 18. Twenty-one cases of trisomy 18, 10 cases of Turner syndrome without hydrops and 12 cases of Turner syndrome with hydrops were identified and each matched to five control samples. Maternal serum progesterone levels were significantly elevated in Turner syndrome with hydrops (2.11 MoM), slightly reduced in Turner syndrome without hydrops (0.90 MoM) and modestly, though significantly, reduced in trisomy 18 (0.73 MoM). These data are similar to the patterns seen for inhibin A and hCG, suggesting that the overall synthetic and/or secretory activity of the placenta is increased in Turner syndrome with hydrops and decreased in Turner syndrome without hydrops and in trisomy 18. These data may be helpful in understanding the pathophysiological basis of serum marker patterns in these aneuploidies.

Second-trimester maternal serum inhibin A levels in fetal trisomy 18 and Turner syndrome with and without hydrops.

The objective was to investigate whether cases of fetal trisomy 18 and Turner syndrome with and without hydrops were associated with alterations in the second-trimester levels of maternal serum inhibin A. Twenty-one cases of trisomy 18, 10 cases of Turner syndrome without hydrops and 12 cases of Turner syndrome with hydrops were identified. Five control samples were matched to each case for date of sample collection and completed week of gestation. Inhibin A levels were modestly, but significantly reduced in cases of trisomy 18 (median = 0.88 MoM) and Turner syndrome without hydrops (median = 0.64 MoM). In contrast, inhibin A levels were markedly increased in cases of Turner syndrome with hydrops (median = 3.91 MoM). These data for Turner syndrome are similar to those for human chorionic gonadotropin (hCG). The addition of inhibin A to multiple marker screening (alpha-fetoprotein, unconjugated oestriol and hCG) resulted in a median increase in the Down syndrome risk of 2.6-fold in cases of Turner syndrome with hydrops. The addition of inhibin A to multiple marker Down syndrome screening programmes will be likely to enhance the detection of fetal Turner syndrome with hydrops, but will not contribute substantially to the detection of fetal trisomy 18.

The relationship between second-trimester amniotic fluid insulin and glucose levels and subsequent gestational diabetes.

Associations between elevated amniotic fluid glucose and insulin levels in the second trimester and the subsequent development of gestational diabetes have been reported. We conducted a case-control study to determine which analyte best predicts future maternal glucose intolerance. Thirty-nine women diagnosed with gestational diabetes (criteria of Carpenter and Coustan, Am. J. Obstet. Gynecol., 144, 768, 1982) who had undergone genetic amniocentesis for advanced maternal age were matched with euglycaemic controls. Glucose and insulin concentrations were determined by analysis of stored amniotic fluid samples. No significant difference was detected between cases and controls for amniotic fluid glucose concentrations. Amniotic fluid insulin concentrations were significantly higher in cases (mean rank 4.44, P < 0.01, using matched rank analysis of variance, where 1 is the lowest and 6 is the highest rank). After conversion to multiples of the median, 20 per cent of women with subsequent gestational diabetes were found to have amniotic fluid glucose levels at or above the 90th centile, while 35 per cent of cases had similarly elevated amniotic fluid insulin levels. We conclude that second-trimester amniotic fluid insulin is a more sensitive predictor of impending glucose intolerance than amniotic fluid glucose, although neither is sufficiently powerful to use alone as a screening test.

Second-trimester diurnal variation of maternal serum alpha-fetoprotein, human chorionic gonadotropin, and unconjugated oestriol: is it present and does it affect the prediction of a patient's risk for fetal Down syndrome?

Both a cross-sectional and a longitudinal study were performed to investigate whether or not the collection time should be taken into consideration when generating a patient's risk for fetal Down syndrome with multiple marker screening. Diurnal variations of third-trimester alpha-fetoprotein (AFP) levels and first-trimester human chorionic gonadotropin (hCG) levels have been previously reported. In addition, large episodic fluctuations of conjugated and unconjugated oestriol (uE3) as well as a diurnal variation have also been reported in the third trimester. If the levels of these analytes routinely fluctuate during the day, they could affect a patient's risk calculation for fetal Down syndrome. The longitudinal study evaluated ten non-diabetic women who underwent sequential sampling for AFP, hCG, and uE3. The cross-sectional study evaluated 1953 patients for these three markers whose time of sampling was recorded between 8.00 a.m. and 5.59 p.m. Using either study design, no significant effect was seen in the median MOM levels of the screening analytes as a function of the time of day.

First trimester bleeding and pregnancy outcome in gravidas with normal and low folate levels.

The purpose of this study was to examine whether women with first trimester uterine bleeding and low serum folate have a higher incidence of spontaneous abortions and adverse perinatal outcome compared with women whose folate levels are normal. Serum folate and vitamin B12 levels were obtained on 225 women who presented with first trimester vaginal bleeding; pregnancy outcomes of those whose folate or vitamin B12 levels were low were compared with those with normal levels using the chi-square test. Of the 151 women included, 52 had low folate levels (less than 4.0 ng/ml). Their spontaneous abortion rate and perinatal outcomes were similar to those whose folate levels were normal. We concluded that in pregnancies complicated by first trimester vaginal bleeding, low folate levels do not appear to be associated with an increased risk of pregnancy loss and adverse outcome.

An IgG human monoclonal antibody reactive with a surface membrane antigen expressed on malignant breast cancer cells.

A human IgG3 monoclonal antibody (HMab), F86, that reacts with breast cancer cells was obtained by fusion of antibody-secreting Epstein-Barr virus (EBV)-transformed cells from a draining lymph node with the human fusion partner HMMA2.11TG/O. F86 reacts with an antigen expressed on the surface of five malignant human breast cancer cell lines and several human malignant myelomonocytic cell lines but is not detected on normal peripheral blood mononuclear cells. Studies with tissue sections of a human breast cancer line xenografted in nude mice have demonstrated that the F86 antigen is expressed both on the cell surface and in the cytoplasm of tumor cells. The F86 antigen is also expressed by the tumor cells in the original tumor specimen of a patient from whom one of the test cell lines and the xenografts were derived. Functionally, the F86 antibody does not mediate complement lysis or antibody-dependent cellular cytotoxicity in vitro. The F86 antigen could not be labeled by [35S] methionine or 125I and immunoprecipitated. The nature and expression of antigens such as that detected by the HMab F86 and how they became immunogenic and/or suppress an active immune response can be addressed through the use of HMab.

Human monoclonal antibodies reactive with cell surface antigens on human leukemia cell lines: many antibodies are (auto)antibodies.

Primary Epstein Barr Virus (EBV) transformants from peripheral blood mononuclear cells (PBM) established in macrocultures were screened for the secretion of antibodies reactive with cell surface antigens on one or another of two indicator human leukemic cell lines and fused with the HMMA2.11TG/O human fusion partner. Human monoclonal antibodies (HuMAbs) were readily obtained. Relative oligoclonality of the primary EBV macrocultures was documented by the number of antibody secreting hybridomas (1-100%). The method permitted preselection for fusion of transformants producing antibodies of certain specificities and/or class. Fourteen HuMAbs, primarily of the IgM class, have been obtained. Those IgM HuMAbs obtained from patients with active diseases, e.g. Acute Lymphoblastic Leukemia (3 HuMAbs), and HIV infection (4 HuMAbs), were found to have a relatively broad spectrum of reactivity with cell lines of various hematopoietic lineages and normal cells, although several show selective reactivity with T cell lineage tumors or a selected population of cells. HuMAbs from normal donors of both the IgG and IgM class were obtained. The IgM HuMAbs from one volunteer reacted primarily with autologous and allogeneic macrophages (autologous PBM from the other patients were not available) as well as a diverse number of hematopoietic cell lines. From others, the IgG HuMAbs demonstrated a more restricted spectrum of reactivity, while the IgM HuMAbs reacted with both autologous and allogeneic normal cells. Thus, the B cell repertoire contains cells capable of secreting cell surface reactive antibodies and many of these antibodies express characteristics of autoantibodies. Those that did not react with autologous or allogeneic PBM may react with other autoantigens which have been expressed on the malignant cells used as screening targets or may represent true antitumor antibodies.

Epstein Barr virus transformation of peripheral blood B cells secreting antibodies reactive with cell surface antigens.

EBV transformable peripheral blood B cells secreting antibodies reactive with cell surface antigens present on two indicator human leukemia cell lines, NALM1 and U937, were studied. Oligoclonal EBV transformants from patients with a variety of diseases were frequently found to produce cell surface reactive antibodies. Antibody secreting transformants could also, although less frequently, be readily cultured from the PBM of normal volunteers, and represented, by limiting dilution, 1 out of 113 transformable B cells. CD8 antibody had no effect on the frequency of antibody producing B cells, but depletion of CD8+ cells by immunomagnetic methods prior to transformation significantly (P less than 0.05) increased the recovery of antibody secreting B cells to 1/33. Readdition of magnetically depleted cells did not significantly inhibit the transformation of these B cells. During the acute and recovery phases of some infections increasing numbers of these transformable antibody producing B cells appear in the circulation. The majority of antibodies produced were of the IgM class, although IgG antibodies were also detected. IgM antibody producing transformants were tested and some were found to react with autologous and allogeneic normal lymphocytes. These results lend support to the notion that B cells capable of secreting cell surface reactive antibodies, a proportion of which are autoreactive, are present in the normal repertoire of healthy adults, and that these cells are under active regulation by CD8+ cells.

Human monoclonal antibodies reactive with human myelomonocytic leukemia cells.

Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.