Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A monoclonal antibody-based antigen capture enzyme-linked immunosorbent assay (ELISA) was developed and employed to detect p24 capsid antigen from human T-cell lymphotropic viruses type I and II (HTLV-I, HTLV-II), simian T-cell lymphotropic virus type I (STLV-I)-infected cell lines, and from mononuclear cell cocultures of HTLV-infected humans and STLV-I infected monkeys. A monoclonal antibody specific for HTLV p24 and p53 capsid antigens was coated onto 96-well microtiter plates to capture HTLV/STLV antigen. Captured antigen was then detected by the addition of a polyclonal, biotinylated human anti-HTLV-I antibody, and color developed with tetramethyl benzidine/H2O2 substrate. As little as 15 pg/ml of HTLV-I p24 antigen could be detected in this assay. Culture supernatants from HTLV-I-infected cell lines (HUT-102, MT-2, C5/MJ, HTLV-II-infected cell lines (Mo-T, Mo-B, PanG 12.1, NRA) and STLV-I-infected cell lines (Matsu, NEPC M39) were all positive in the assay. In addition, p24 was detected from peripheral blood mononuclear cell (PBMC) cocultures of 8 of 8 (100%) HTLV-I diseased patients, 14 of 20 (70%) HTLV-I and HTLV-II-infected, asymptomatic persons, and 8 of 8 (100%) STLV-I-infected, asymptomatic monkeys. Culture supernatants of cells infected with human immunodeficiency virus type (HIV-1), simian immunodeficiency virus (SIV), Chlamydia trachomatis, cytomegalovirus (CMV), herpes simplex I and II (HSV), feline leukemia virus (FELV), bovine leukemia virus (BLV), and bovine immunodeficiency virus (BIV) were all negative. Similarly, normal human peripheral blood mononuclear cells and uninfected, transformed human T cells, were also negative in the assay.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Development of a monoclonal antibody-based p24 capsid antigen detection assay for HTLV-I, HTLV-II, and STLV-I infection. 131 63

An African lioness from the Zoo of Zurich had to be euthanized because of an inoperable tumor. The serum tested negative for feline leukemia virus (FeLV) p27 antigen by enzyme-linked immunosorbent assay (ELISA) but was strongly positive for feline immunodeficiency virus (FIV) antibodies by ELISA and Western blot. When her only offspring and mate were tested for FIV, high antibody titers to FIV were also found in their serum. Lymphocytes were prepared from these two lions on different occasions and co-cultivated with specific pathogen free (SPF) cat lymphocytes in the presence of concanavalin A and recombinant human interleukin-2 (IL-2) for 6 weeks. The cell culture supernatants tested negative for Mg(2+)-dependent reverse transcriptase and FIV p24 by a double antibody sandwich ELISA throughout the culture period. Whole blood and buffy coat cells collected from these two lions were transmitted by intraperitoneal injection into two SPF cats. The two cats did not seroconvert for a period of 11 months nor could reverse transcriptase activity and FIV p24 antigen be demonstrated in the supernatant of several lymphocyte cultures. To determine the importance of lentivirus infections in zoo-kept wild felids, 124 serum samples were obtained from African lions, Indian and Siberian tigers, snow leopards, panthers, cheetahs and other wild cats from nine European zoos. In addition, serum samples collected from 12 Asiatic lions originating from Gir forest in the Indian State of Gujarat were included in this study. The sera were tested for antibodies to FIV, FeLV and feline syncytium-forming virus (FeSFV) by ELISA and Western blot using the respective viruses after gradient purification. In addition, some of the sera were also tested for antibodies to equine infectious anemia virus (EIAV) and Visna-Maedi virus (VMV). Antibodies to FIV were found in 30/53 (57%) of African lions, one of 18 tigers and one of four panthers. All other sera including those collected from the 12 Asiatic lions were negative for FIV antibodies. Some of the FIV positive lion sera had high antibody titers producing strong bands on Western blot strips even in dilutions of >> 1:1000. The Western blot pattern of the lion sera differed from that of domestic cats in that primarily p24 and to a lesser degree p17 was recognized. Antibodies to FeSFV were found in 14 animals (seven with strong, seven with intermediate, reaction). No correlation was found between FIV and FeSFV infection. Antibodies to FeLV were found in two cheetahs which later turned out to have been vaccinated with Leukocell, a FeLV vaccine.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Retrovirus infections in non-domestic felids: serological studies and attempts to isolate a lentivirus. 133 98

We describe the use of an immunofluorescence assay and coculture to confirm human T-cell leukemia-lymphoma virus (HTLV) infection. Peripheral blood mononuclear cells from 32 of 32 seropositive donors were positive in the immunofluorescence assay, and 63% of their cocultures produced p24 antigen. Specific antibodies distinguished HTLV type I (HTLV-I) from HTLV-II. HTLV-I or HTLV-II was isolated from donors with indeterminate serologic test results.
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PMID:Primary isolation of human T-cell leukemia-lymphoma virus types I and II: use for confirming infection in seroindeterminate blood donors. 150 May 34

The leukemia-associated antigen CD9 is present on a variety of normal cells, with apparent variable expression on normal human fibroblasts. In this study, we demonstrate by immunoperoxidase staining and direct binding studies that the CD9 antigen is uniformly expressed on normal human fibroblasts grown from first trimester and term placenta, embryonic fetal fibroblasts, and from human adult and fetal skin fibroblasts. Higher CD9 expression was present on fetal cells. CD9 antigen was not present on trophoblast. Over 99% of fibroblasts could be absorbed onto antibody to the CD9 antigen conjugated to magnetic beads. By applying this selective immunoadsorption of fibroblasts to term placental cytotrophoblast preparations, we demonstrated that fibroblast contamination could be nearly completely eliminated. This is a novel technique for purifying primary trophoblast cultures and may have wider applicability in cell culture of other cell types.
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PMID:Preparation of fibroblast-free cytotrophoblast cultures utilizing differential expression of the CD9 antigen. 185 55

Infection due to the human immunodeficiency virus (HIV) has been complicated by the development of acute nonlymphocytic leukemia in five patients whose cases have previously been reported; other manifestations, including preleukemia, myelofibrosis, and myeloid hyperplasia, have also been reported in patients infected with HIV. We report the sixth case of an HIV-infected patient who developed acute myelomonocytic leukemia; HIV infection was documented by tests for serum antibodies (enzyme-linked immunosorbent assay and western blotting), by a markedly elevated p24 antigen level in plasma, and by cultures of CSF and peripheral blood that were positive for HIV. Furthermore, myelomonoblasts that were cultured without the addition of growth factors displayed evidence of HIV replication through the presence of p24 antigen and reverse transcriptase activity, both of which lasted for 4 weeks in the supernatant fluid of the cell cultures. This case report provides the first data indicating that HIV may infect myelomonoblasts in vivo and represents the sixth reported case of an association between HIV infection and pure acute nonlymphocytic leukemia.
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PMID:Relationship between acute myelomonoblastic leukemia and infection due to human immunodeficiency virus. 190 61

The aim of this study is to detect the presence of HTLV-1 in a high-risk population in west Andalusia. We studied 267 samples of serum from 255 patients: 179 of these patients being intravenous drug-users, 14 had ADVP sexual partners, 16 were inhalation drug-users, 4 were hemophiliacs, 9 had other high-risk habits and 25 hematological patients afflicted with leukemia or lymphoma. All of them were tested for antibodies against HTLV-1 by means of an in vitro qualitative ELISA technique (ELISA Du Pont HTLV-1). The positive results were confirmed by the Western blot technique. Additionally, the p24 antigen and the antibodies against VIH-1 and VIH-2 (ENV/CORE) were analysed, except in the 25 hematological patients. We found 20 serum samples positive to HTLV-1 by ELISA (7.4%), but only 1 (0.3%) was confirmed by the Western blot technique. The prevalence of VIH-1 was 46%; 9% had p24 VIH antigen and 26% had false positive ELISA to VIH-2. We found a statistically significant relationship (p = 0.0005) between positive ELISA to HTLV-1 and antibodies against VIH. We conclude that HTLV-1 has penetrated into the high-risk population of west Andalusia , although not yet to a great degree, and point out the need for seric epidemiological surveillance to prevent the spread of the retrovirus in these groups.
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PMID:[HTLV-I infection in a high-risk group]. 210 46

Viral isolates were recovered by cocultivation on macrophage colony-stimulatingfactor (MCSF)-treated monocyte target cells from peripheral blood mononuclear cells (PBMCs) in 25 out of 27 patients seropositive or at risk for HIV infection. Frequency of virus recovery was independent of the patient's age, sex, numbers of CD4+ T cells, clinical stage or zidovudine (azidothymidine) therapy. Sixteen out of 19 HIV isolates were serially passaged in MCSF- treated monocytes. Five out of five virus isolates were also passaged in phytohemagglutinin/interleukin-2 (PHA/IL-2)-treated lymphoblasts. In lymphoblasts, no qualitative or quantitative differences were observed between these isolates and human T-cell leukemia virus IIIB (HTLV-IIIB) for (1) release of p24 antigen reverse transcriptase, and infectious virus, (2) induction of typical cytopathic effects (cell syncytia in 3-10% of cells) and cell lysis, (3) frequency of infected cells (5-20% of PBMC) as detected by in situ hybridization for HIV RNA, (4) down-modulation of T cell plasma membrane CD4, and (5) site of progeny virion assembly and budding (plasma membrane only with no intracytoplasmic accumulation of virus). Progeny virus recovered from infected lymphoblasts was fully infectious for other lymphoblasts, but failed to infect MCSF-treated monocytes. Detailed analysis of target cell tropism among HIV isolates showed that HIV isolated in monocytes infected both monocytes and lymphoblasts; progeny virus isolated in lymphoblasts infected only T cells. HIV interacts differently with monocytes and T cells. Understanding this interaction may more clearly define both the pathogenesis of HIV disease and strategies for therapeutic intervention.
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PMID:Macrophage-HIV interaction: viral isolation and target cell tropism. 211 97

An ELISA for detecting antibody to the bovine leukaemia virus (BLV) core protein p24 is described. The test uses p24 antigen purified from concentrated cell culture supernate by lectin-affinity chromatography and gel filtration. The sensitivity and specificity of the p24-ELISA for diagnosing BLV infection relative to the gp51 agar gel immunodiffusion test, were 98.1 and 96.7%, respectively. In the event of widespread use of gp51 based vaccines, the p24-ELISA should differentiate effectively between naturally infected and vaccinated animals.
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PMID:An enzyme-linked immunosorbent assay for detection of bovine leukaemia virus p24 antibody in cattle. 216 19

The prevalence of retroviral infection in renal transplantation remains poorly defined. We tested retrospectively sera from 224 of 331 patients undergoing renal transplantation between 1979 and 1985. Viral antigen based EIA was used for screening IgG antibodies to human immunodeficiency virus (HIV-I) and human T-cell leukemia virus type I (HTLV-I). Positive EIAs were confirmed by Western blot. Six patients (2.7%) were found to have retroviral infection, four with HIV-1 and two with HTLV-I. The four patients with HIV-1 infection were negative before and became EIA and Western blot positive following transplantation. All patients had transient HIV-1 antigenemia documented before antibody was detected. One patient died of Kaposi's sarcoma 2 years posttransplantion with a functioning graft. One is alive and asymptomatic 4 years posttransplant, and two rejected their grafts and are asymptomatic on maintenance hemodialysis. Six patients tested positive for HTLV-I by EIA. Only two patients, however, were also positive for HTLV-I by Western blot, RIPA, and p24 antigen RIA, one prior to and one after transplantation. Both had HTLV-I-positive lymphocyte cultures and remain asymptomatic of retroviral infection 3 years after renal transplantation. A third patient, positive for HTLV-I by EIA, had indeterminate Western blot and negative RIPA, RIA, and lymphocyte culture. Intravenous drug use was not a risk factor for retroviral infection in this patient population. It is likely that patients became infected peritransplantation from blood transfusions. Contamination by donor kidneys, however, cannot be excluded.
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PMID:HIV-1 and HTLV-I infection in renal transplant recipients. 240 36

We report the development of a unique enzyme-linked immunosorbent assay (ELISA) which makes possible the detection of leukemia-associated P24 antigen, utilizing its ability to bind the Ricinus communis agglutinin (RCA1) and a monoclonal antibody, SJ-9A4 simultaneously. Using the RCA1/SJ-9A4-ELISA, P24 antigen, as few as 50 X 10(3) cells from a common acute lymphoblastic leukemia (C-ALL) cell line could be detected. The presence of D-galactose gave complete and specific inhibition of P24 antigen binding to RCA1. Matched concentrations of D-glucose and D-sucrose had no effect on binding. The release of the P24 antigen into the culture medium by a C-ALL cell line maintained at 37 degrees C could be detected; however, no P24 antigen was present in the culture medium when the cells were maintained at 4 degrees C. Sequential analysis of the culture medium for soluble P24 antigen revealed that release of the P24 antigen associated with cell growth. Molecular sieve chromatography of concentrated culture medium indicated that shed P24 antigen was eluted in the macromolecule fraction. P24 antigen was detected in the cerebrospinal fluid (CSF) of four patients with P24 positive ALL at the time of relapse of the central nervous system (CNS) and was undetectable while in complete remission. The CSF from three patients with P24 negative ALL and three patients with aseptic meningitis had no detectable activity.
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PMID:Shedding of leukemia-associated P24 antigen by lymphoblastoid cell lines. 244 10


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