Biomedical subjects

K D Beaman

Publications and source records attributed to K D Beaman.

At least 37 records · Page 2Linked to original sources

PubMed1996

Intravenous immunoglobulin inhibits natural killer cell activity in vivo in women with recurrent spontaneous abortion.

We previously reported elevation of natural killer (NK) cells in women with recurrent spontaneous abortion (RSA) of immune etiology. In this study, we investigated the effect of intravenous immunoglobulin G (IVIg) on peripheral blood NK activity in vivo in women with RSA. Blood was drawn prior to and 7-11 days after IVIg therapy in eight women with RSA. NK activity was measured using K562 as target cells for 51Cr-release assays. Serum IgG concentrations were also measured. All received 400 mg/kg/day of IVIg for 3 consecutive days. 1) Seven of eight women became pregnant. Five delivered a live born infant. Three out of five women (60%) who delivered a live born infant showed a significant inhibition of NK cytotoxicity post IVIg and the rest did not show any changes; 2) NK cytotoxicity was significantly increased in a woman who miscarried again; 3) A woman who miscarried a chromosomally abnormal fetus showed a significant inhibition of NK cytotoxicity after IVIg; and 4) Serum IgG concentration increased significantly from 9.3 +/- 3.0 mg/ml to 23.5 +/- 5.1 mg/ml post IVIg therapy. IVIg effectively inhibits peripheral blood NK activity in vivo. These results are consistent with our previous finding showing that IVIg inhibits NK cell activity in vitro. Women with RSA and elevated NK cells may benefit from IVIg treatment.

Abortion, Habitual↗

PubMed1995

Intravenous immunoglobulin infusion therapy in women with recurrent spontaneous abortions of immune etiologies.

We have investigated clinical effectiveness of intravenous immunoglobulin G infusion (IVIg) on antiphospholipid antibody titers in five women with evidence of antiphospholipid antibody-associated recurrent spontaneous abortions and one with antinuclear antibody who became refractory to conventional autoimmune treatment during pregnancy and experienced pregnancy complications. Three women developed intrauterine growth retardation and three had complicated twin pregnancies with rising autoantibody titers. Antiphospholipid antibody and antinuclear antibody titers were tested pre and 2 weeks after each IVIg infusion. We report that: (i) IgG antiphospholipid antibody titers were significantly suppressed after each IVIg infusion (P < 0.05); (ii) IgM antiphospholipid antibody titers were also significantly suppressed after each IVIg infusion (P < 0.0001); (iii) decreased titers of autoantibodies paralleled increased levels of maternal IgG which lasted for at least 30 days; the autoantibodies showed a definite rise again prior to the next infusion; (iv) antinuclear antibody titers were effectively suppressed; and (v) rising autoantibody titers combined clinical manifestation of intrauterine growth retardation and women with complicated twin pregnancies. We conclude that IVIg infusion effectively suppresses IgM and IgG autoantibodies to phospholipids and antinuclear antibody in autoimmune women with a history of recurrent spontaneous abortions and refractory to conventional anticoagulation or immunosuppressive treatment.

Abortion, Habitual↗

PubMed1995

Up-regulated expression of CD56+, CD56+/CD16+, and CD19+ cells in peripheral blood lymphocytes in pregnant women with recurrent pregnancy losses.

PROBLEM: To analyze immunophenotypic profiles of peripheral blood and humoral autoimmune responses in women with a history of recurrent spontaneous abortions (RSA). METHOD: Peripheral blood lymphocyte subsets by flow cytometry and autoantibodies to phospholipids and nuclear components by ELISA were measured in nonpregnant and pregnant women with RSA of unknown etiology. Thirty-five pregnant and eighty-one nonpregnant women with RSA were studied. Seventeen nonpregnant and twenty-two pregnant normal controls were included. RESULTS: Natural killer (NK) cells (CD56+) were significantly elevated in nonpregnant women with RSA as compared with nonpregnant controls. Pregnant women with RSA demonstrated significantly increased NK (CD56+, CD56+/CD16+) and B cells (CD19+) as compared with pregnant controls. Women who miscarried the index pregnancy demonstrated significantly lower CD3+ cells in comparison with normal controls. Women with RSA and antiphospholipid antibodies showed significantly elevated NK cells when compared with women without antiphospholipid antibodies. Women with autoantibodies to nuclear components demonstrated significantly elevated CD19+/CD5+ cells when compared to women without autoantibodies to nuclear components. CONCLUSIONS: Women with RSA demonstrate an abnormal cellular immune response by increasing peripheral natural killer cells and B cells as compared with normal controls.

Abortion, Habitual↗

PubMed1995

Reciprocal alteration in circulating TJ6+ CD19+ and TJ6+ CD56+ leukocytes in early pregnancy predicts success or miscarriage.

PROBLEM: TJ6 is a cytokine whose membrane form is regularly expressed on the B lymphocytes of women during pregnancy. In a previous study we have shown that pregnancies that end in a spontaneous abortion are characterized by an increase in natural killer (NK) cells and that NK cells in these pregnancies also expressed TJ6, whereas NK cells from pregnancies that terminate normally neither increase in number nor do they express significant amounts of the cytokine. METHODS: To evaluate the ability of TJ6 to predict pregnancy outcome, 61 blood samples from pregnant women were studied. Blood samples were drawn between 5 and 12 weeks of gestation and analyzed for lymphocyte expression of TJ6 using Cytoron Absolute flow cytometry and two-color fluorescence. The percentage of CD19+ (B) cells and CD56+ (NK) cells that expressed TJ6 was calculated, and this percentage was correlated with subsequent pregnancy outcome classified as successful (viable birth) or unsuccessful (abortion, stillbirth). TJ6 CD19 and TJ6 CD56 was determined in 32 blood samples from women with successful pregnancy outcomes and 29 samples from women with unsuccessful pregnancy outcome. RESULTS: The mean TJ6 CD19 expression for successful pregnancies was 10.6% and for unsuccessful pregnancies was 5.1% (P < 0.03). The mean TJ6 CD56+ percentage of circulating cells that express TJ6 expression for successful pregnancies was 3.3% and for unsuccessful pregnancies was 10.4% (P = 0.02). All unsuccessful pregnancies had less than 90% of circulating CD19 cells express TJ6 and/or greater than 50% of circulating CD56 cells express TJ6. Use of the expression of TJ6 on CD19 and CD56 cells during the first trimester predicts viable pregnancy with a sensitivity of 100%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 100%. CONCLUSIONS: The work now being reported validates the hypothesis that expression of TJ6 on NK cells obtained from pregnant women predicts the outcome of pregnancy. In addition we show that this prognosticator can be reliably demonstrated early in the first trimester.

Abortion, Spontaneous↗

PubMed1995

Systemic CD56+ cells can predict pregnancy outcome.

PROBLEM: To evaluate differences in circulating CD56+ cells between successful and unsuccessful pregnancies, 114 pregnant women were studied prospectively. METHOD: Seventy women had a history of infertility (INF) and 44 had two or more previous spontaneous abortions (RSA). Among the infertile women, 12 were donor egg recipients (DER) and 15 underwent intracytoplasmic sperm injection (ICSI) for treatment of male factor infertility. Nineteen women were carrying multiple gestations (MG) and 55 had singleton gestations (SG). Thirteen additional women were receiving intravenous immunoglobulin (IVIg). RESULTS: The percentage of CD56+ cells was determined in 310 blood samples from 114 pregnant women by flow cytometry. The prevalence of women with persistent elevation of percent of 56+ cells (> 12%) was 58% among DER, 73% among ICSI, 37% among MG, 22% among SG, 18% among RSA, and 39% among INF. Thirteen women with SG received IVIG, 10 had CD56+ cells greater than 12% and all 13 experienced live births. Women with percentage CD56+ cells persistently greater than 12% who were not DER, not ICSI, not receiving IVIg, and not carrying MG had a live birth rate of 11%. Women with greater than 12% CD56+ cells had normal karyotype in 78% of concepti studied in contrast to women less than 12% CD56+ cells who had 68% abnormal karyotypes (P = 0.04). CONCLUSION: Elevated CD56+ cells in pregnant women who are not DER, not ICSI, not receiving IVIg, and not carrying MG predicts loss of a karyotypically normal conceptus with a specificity of 87% and positive predictive value of 78%. While the specificity value of this test is high in both infertile and RSA populations, the sensitivity is 86% in RSA and only 54% in INF suggesting this test does not identify all losses among INF. It may identify a subset of pregnancies at risk for loss of a karyotypically normal embryo that may respond to treatment with IVIg.

Abortion, Habitual↗

PubMed1995

Purification and characterization of a pregnancy-associated protein: TJ6s.

PROBLEM: Characterization of the soluble form of a novel protein, TJ6 (TJ6s) with immune suppressive activity from murine fetoplacental units. METHOD: Preferential ammonium sulfate precipitation, gel filtration and ion-exchange chromatography were employed to purify the protein TJ6s from murine fetoplacental units using an anti-peptide antibody as a detection tool. Biological activity of the purified protein was studied in lymphocyte proliferation assays. RESULTS: Purified TJ6s has a M(r) of approximately 18 kDa as evidenced by SDS-PAGE in both reducing and non reducing conditions. It exerted a strong anti-proliferative activity in both anti-CD3 and Con A proliferation lymphocyte proliferation assays but not in a PHA assay, suggesting that the anti-proliferative effects on T cells are exerted only on cells specifically activated directly through T cell receptor complex. CONCLUSION: The results indicate that TJ6s is a novel anti-proliferative protein that has many of the characteristics that are considered necessary for survival of the fetal allograft.

Amino Acid Sequence↗

PubMed1995

Presence of multiple anti-phospholipid antibody specificities in a pediatric population.

Thrombotic related events are thought to be associated with the presence of anti-phospholipid antibodies (APA). However, the association of anti-cardiolipin antibody is much weaker than the association with antibodies to other phospholipids. Much of the literature equates antiphospholipid antibodies and anticardiolipin antibodies because of the relationship of APA and false positive tests for syphilis. However, recently the presence of antibodies to naturally occurring phospholipids other than cardiolipin have been reported. In fact, some investigators report that antibodies to phosphatidylserine appear to correlate more closely to disease processes than anti-cardiolipin antibodies. We describe here the presence of non-anti-cardiolipin antiphospholipid antibodies in a pediatric population that lack anti-cardiolipin antibodies and demonstrate the association of these antibodies with thrombotic disease. Antibodies to phosphatidic acid were the most prevalent and correlated (p < .001) with thrombotic disease and idiopathic thrombocytopenia purpura. The rank order of prevalence of antibodies to phospholipids was phosphatidic acid, phosphatidylglycerol, phosphatidylinosital, phosphatidylserine, cardiolipin and phosphatidylethanolamine. Antiphospholipid antibodies of the three major sera isotypes were present in the positive sera examined. These descriptive findings suggest that the significance of APA other than anti-cardiolipin antibodies in pediatric patients should be further investigated.

Antibodies, Anticardiolipin↗

PubMed1994

Expression of a membrane form of the pregnancy-associated protein TJ6 on lymphocytes.

TJ6 is a novel protein which has immunosuppressive activity and may have a functional role in fetal allograft survival during pregnancy. Initial studies indicated that when mice were treated with an anti-TJ6 binding mAb early in pregnancy, the pregnancies were completely ablated and that TJ6 expression is enhanced dramatically during pregnancy. In addition we have cloned the cDNA for TJ6 which encodes a possible transmembrane domain that may include six to seven transmembrane regions. Therefore, we examined TJ6 expression on PBL of pregnant and non-pregnant women and found that TJ6 is expressed primarily on CD19+ B cells from pregnant but not nonpregnant women. TJ6 was not expressed on CD3+ lymphocytes from either group but was expressed on CD56+ cells from a small population of pregnant women which preliminary data indicate may correlate with the occurrence of spontaneous abortion in these women. Here we also show that TJ6 transcripts are highly expressed in the developing fetoplacental unit as well as in the developing thymus. We also begin to characterize the expression of TJ6 isoforms in an acute lymphocytic leukemia cell line (SB), murine thymus, and the developing murine fetoplacental unit, as well as the expression of a membrane form of TJ6 present on human lymphocytes during pregnancy. All of these cells and tissues expressed TJ6 proteins which were smaller than predicted based on either the cDNA sequence or the in vitro translation even though they expressed mRNA similar in size. The TJ6 isoforms varied in size from the 45-kDa isoform in SB cells to the 52-kDa isoform of the fetoplacental unit to a 70-kDa isoform in murine thymus. Flow cytometric analysis also demonstrated that similar to the CD19+ B cells from pregnant women, TJ6 is expressed on the surface of SB cells.

Antigens, CD↗

PubMed1994

Down-regulation of maternal antiphospholipid antibodies during early pregnancy and pregnancy outcome.

OBJECTIVE: We investigated the hypothesis that maternal autoimmune responses to phospholipid antigens measured before and during pregnancy are not related to successful pregnancy outcome. STUDY DESIGN: One hundred twenty-three women with recurrent spontaneous abortions were serially tested for antiphospholipid antibodies during their pregnancies. RESULTS: In 72 women with recurrent spontaneous abortions and without antiphospholipid antibodies before the pregnancy, the incidence of antiphospholipid antibody production at the time of pregnancy termination was significantly higher in those who miscarried the index pregnancy than those who were delivered of a live-born infant. In 51 antiphospholipid antibody-positive women with recurrent spontaneous abortions there were dramatic increases in titers of anticardiolipin antibody and antiphosphatidylserine antibody in those who miscarried the index pregnancy (p < 0.005). In women who were delivered of a live-born infant, the titers remained stable or decreased during pregnancy. CONCLUSIONS: Down-regulation of antiphospholipid antibody production during early pregnancy is associated with favorable pregnancy outcome.

Abortion, Habitual↗

PubMed1993

Characterization of antibodies induced by paternal lymphocyte immunization in couples with recurrent spontaneous abortion.

This study was designed to identify and characterize the allo- and autoantibodies induced following successful paternal lymphocyte immunization to prevent recurrent spontaneous abortion. Firstly the titers of maternal anti-paternal antibodies in women with successful pregnancies as determined by the flow cytometry crossmatch (FCXM) were highly variable; however, in all cases, the initial pre-immunization titers were negative and the post-immunization titers were positive by the FCXM in successfully treated women. Secondly, the specificities of maternal alloantibodies to paternal HLA antigens (immunogen) were evaluated. No all predicted antibodies to mismatched paternal HLA antigens were found by microlymphocytotoxicity (MCX) assays and the specificities varied. Thirdly, antibodies in post- but not preimmunization sera reacted with two lymphoid cell lines, SupT1 and SB; in addition, the rise and fall of the titers of these sera with paternal cells seemed to be reflected with the cell lines by the FCXM. Fourthly, autoantibodies to activated lymphocytes were detected and seemed to correlate with successful immunization since women who had another abortion following immunotherapy lacked these autoantibodies. These findings suggest that the antibody response following successful immunotherapy is complex and needs to be studied further to understand the mechanism of this treatment.

Abortion, Habitual↗

PubMed1993

Antibodies to phospholipids and nuclear antigens in non-pregnant women with unexplained spontaneous recurrent abortions.

In a collaborative study of 73 non-pregnant Kuwaiti women with unexplained spontaneous recurrent abortion (RSA), 30 control healthy non-pregnant multiparous Kuwaiti women and 20 North American women who received elective abortion(s), autoantibodies to 6 phospholipids and 9 nuclear antigens were measured. Women with recurrent spontaneous abortions demonstrated 3 times higher incidence of antibodies to phospholipids (30.1%) than controls (10% each) (P = 0.029). The incidence of both IgM and IgA class antiphospholipid antibodies were significantly higher than those of controls. The incidence of antibodies to cardiolipin in women with recurrent spontaneous abortions (12.3%) was significantly higher than those of controls (P = 0.035) and incidence of IgM but not IgG anticardiolipin antibody was significantly higher in women with RSAs than in controls (P = 0.053). The incidences of anti-polyinosinic acid (P = 0.035) and anti-histone 1 antibody (P = 0.052) were significantly higher in women with recurrent spontaneous abortions than controls. There was no significant difference in the incidence of autoantibodies between primary and secondary aborters. However, women with a history of second trimester abortions showed a higher incidence of antiphospholipid antibodies than women with first trimester abortions only. Recurrent spontaneous abortion is associated with autoantibodies to phospholipid epitopes including IgA antiphospholipid antibodies.

Abortion, Habitual↗

PubMed1992

Reproductive outcome in women with recurrent spontaneous abortions of alloimmune and autoimmune causes: preconception versus postconception treatment.

OBJECTIVES: The null hypothesis is that treatment of women with recurrent spontaneous abortions with anticoagulation and immunosuppression will not increase the reproductive outcome if it is started preconceptionally. STUDY DESIGN: Ninety-four women with recurrent spontaneous abortion with autoimmune abnormalities comprised the study group. Group I began autoimmune therapy 48 hours after ovulation: heparin 5000 U twice daily, aspirin 80 mg daily, and prednisone 5 mg twice daily, with an increase to 10 mg twice daily when pregnant. Group II started the same medication after a positive pregnancy test. Group III received no medication. Controls were 19 women with no autoimmune abnormalities. The frequency of reproductive outcome was subject to multiple comparison by the Duncan test. RESULTS: The percentages of live-born children in groups I, II, and III were 74%, 44%, and 11%, respectively. CONCLUSIONS: Preconception diagnostic work-up and treatment of autoimmune abnormalities in women with histories of recurrent spontaneous abortion is advocated.

Abortion, Habitual↗

PubMed1992

Autoantibodies in women with primary recurrent spontaneous abortion of unknown etiology.

A group of 153 women with 3 or more recurrent spontaneous abortions (RSAs) with unknown etiology and 90 normal multigravida controls were evaluated for antibodies to phospholipids and nuclear antigens. We demonstrate that women with recurrent spontaneous abortions showed significantly higher incidence of antibodies to phospholipids than normal multigravida controls. In contrast, the incidence of antibodies to polynucleotides and histones was not different between these two groups. These findings suggest that antiphospholipid antibodies are either epiphenomena or causally related to recurrent spontaneous abortions.

Abortion, Habitual↗

PubMed1991

Extrahepatic transcription of human C-reactive protein.

We synthesized and cloned cDNA from human peripheral blood mononuclear cell (PBMC) transcripts that were hybrid selected by pCRP5, a liver C-reactive protein (CRP)-specific cDNA (Woo, P.,J.R. Korenberg, and A.S. Whitehead. 1985. J.Biol. Chem. 260:13384). Three hybrid-selected cDNA clones, HScDNA1, HScDNA3, and HScDNA8, were isolated and characterized. Nucleotide sequence analysis of the 5' end of the smaller clones, HScDNA1 and HScDNA8, demonstrated that these two PBMC clones are homologous to the 3' and 5' ends, respectively, of pCRP5. Our largest clone, HScDNA3, is larger than pCRP5, extending beyond both the 5' and 3' limits of pCRP5. Therefore, HScDNA3 was coded by human PBMC and not by the hybrid selection vehicle, pCRP5. HScDNA3 lacks the intervening sequence verifying that this clone is DNA made from a PBMC mRNA and not genomic DNA. The complete nucleotide sequence revealed that HScDNA3 is greater than 99% homologous to the CRP gene. These results demonstrate that PBMC express the CRP gene. Based on our previous report, which shows that peripheral blood cells synthesize a peptide recognized by anti-CRP (Kuta, A.E., and L.L. Baum. 1986. J. Exp. Med. 164:321), in conjunction with the data presented here, we conclude that human PBMC can synthesize CRP.

Base Sequence↗

PubMed1991

Sequence analysis of porcine immunoglobulin light chain cDNAs.

A porcine cDNA library was constructed using poly(A)+ RNA isolated from the spleen of an adult Minnesota miniature swine. Screening the library with antisera specific for porcine immunoglobulin light chains resulted in the selection and isolation of two recombinant clones, PLC18 and PLC3, which encode for kappa and lambda light chains, respectively. These cDNAs contain sequence information for a portion of the variable region and all of the constant region. The lengths of the constant regions are 105 amino acids for lambda and 108 amino acids for kappa. The deduced amino acid sequences of porcine immunoglobulin light chains share a high degree of homology with similar sequences from other species in both the fourth framework region and the constant region.

Amino Acid Sequence↗

PubMed1991

The lack of direct effects of a monoclonal antibody against murine T-cell suppressor factor on murine embryo development in vitro.

In previous studies, we reported that the injection of monoclonal antibody 14-30, specific for a T-cell suppressor factor (TSF), into mice during early stages of pregnancy could decrease the percentage of females that maintained pregnancy. In addition, further work has demonstrated the presence of an immunoreactive protein in fetal and maternal tissues with physiochemical properties similar to TSF. However, one alternate explanation for the antipregnancy effects of the injections of monoclonal antibody, not related to a specific role for TSF in early pregnancy, is the possibility of direct effects upon the embryo or embryonic antigens that prevent continued embryonic development. In the present studies, early preimplantation embryos were incubated with the monoclonal antibody 14-30 specific for TSF and the subsequent development of the embryos examined. The results of these studies demonstrate that monoclonal antibody, which has been shown to bind T-cell suppressor factor and has antipregnancy effects when injected in vivo, does not interfere with development of preimplantation or implantation stage mouse embryos in vitro.

Animals↗

PubMed1991

Patterns of anti-phospholipid antibody specificities.

To determine the importance of assaying for anti-phospholipid (PL) antibodies other than anti-cardiolipin antibodies in patients with putative anti-phospholipid antibody syndrome (APA), 1,513 serum samples from over 399 patients with the potential for thromboembolic disease were tested for IgM, IgG or IgA class antibodies to the following phospholipids: cardiolipin, phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidic acid. Non-specific binding was subtracted from total binding of antibodies to each PL to eliminate false positive ELISA results. Only patients whose sera contained antibody levels which were greater than three standard deviations above the means were considered positive. Patients who were positive for anti-PL antibody had antibodies to at least one of six phospholipids tested. Approximately 60% of the positive samples contained antibodies to a phospholipid other than cardiolipin. For IgG class, antibodies to phosphatidylserine were the most prevalent followed by antibodies to phosphatidylethanolamine and cardiolipin. These findings indicate that anti-phospholipid antibody analysis should be performed for more than anti-cardiolipin antibody to detect patients with APA.

Abortion, Habitual↗

PubMed1990

Cloning of a cDNA for a T cell produced molecule with a putative immune regulatory role.

An expression cDNA library was constructed from the helper T cell hybridoma, A.1.1, which has been shown to produce constitutively proteins involved in the down regulation of the immune response. From this library we identified and characterized a cDNA clone, J6B7, by screening with a polyclonal antibody specific for secreted immune regulatory proteins. The mRNA for J6B7 is expressed specifically in some T cells, but not in the thymoma BW5147 or liver cells. J6B7 is 2937 nucleotides in length and contains one open reading frame encoding for a peptide of predicted Mr of 98,042. The nucleotide and deduced amino acid sequences of J6B7 did not reveal significant homology to any published sequences. Hybridization and translation experiments reveal that the J6B7 can hybrid select mRNA from total RNA isolated from either A.1.1 cells or thymic tissue which can be translated in vitro to a peptide which is bound by a monoclonal antibody (mAb) specific for antigenic determinant(s) shared by immune regulatory proteins. Furthermore, the in vitro translated proteins obtained from A.1.1 cells and thymus showed significant suppression of a mixed lymphocyte reaction (MLR) in a dose dependent manner, reaching maximum suppression of 71% and 89%, respectively. These results suggest that the cDNA, J6B7, codes for an immune regulatory protein.

Amino Acid Sequence↗