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Biomedical subjects

A Karpas

Publications and source records attributed to A Karpas.

At least 73 records · Page 4Linked to original sources
PubMed1988

Capsular antibodies induce type-specific phagocytosis of capsulated Staphylococcus aureus by human polymorphonuclear leukocytes.

Capsular types 5 and 8, which account for about 70% of Staphylococcus aureus strains isolated from the blood of patients, resisted in vitro phagocytosis by human polymorphonuclear leukocytes (PMN). Antisera and monoclonal antibody to type 5 and 8 capsular polysaccharides (CPS) induced type-specific in vitro phagocytosis of capsulated organisms by PMN. Antibodies directed against the O-acetyl moiety of the type 8 CPS were more effective in inducing phagocytosis of type 8 organisms by PMN. Either type-specific antiserum or monoclonal antibody reactive with the native O-acetylated type 8 CPS was most effective in inducing in vitro phagocytosis of type 8 organisms by PMN. These results provide further evidence that CPS of S. aureus are associated with host immunity to this organism.

Antibodies, Bacterial↗
PubMed1988

Risk factors for the spread of AIDS in rural Africa: evidence from a comparative seroepidemiological survey of AIDS, hepatitis B and syphilis in southwestern Uganda.

Before commencing rational control programmes for AIDS in Africa it is desirable to determine the relative importance of heterosexual and various non-sexual modes of transmission. We investigated this by comparing the seroepidemiologies of AIDS, hepatitis B and syphilis at two rural hospitals in southwest Uganda. During August 1986, 3% of 357 outpatients, reflecting the age and sex composition of the general population, were anti-HIV positive. Anti-HIV seropositivity, both in the outpatients and among 36 suspected prostitutes and 14 suspected AIDS cases, was confined to individuals aged 20 or over. For men, seropositivity was associated with sexual contact with prostitutes (a risk factor for 61% of young men in the study). In the prostitute group, 25% were anti-HIV positive and 46% were positive on the Treponema pallidum haemagglutination (TPHA) test for syphilis. The risk factors for HIV, but not hepatitis B, were the same as for having a history of sexually transmitted disease (STD). However, there was, surprisingly, an association between a history of STD and seropositivity for hepatitis B virus but not for HIV infection. The geographical and age distributions of seropositivity for HIV and hepatitis B virus were also quite different. Finally, blood transfusions, scarification and exposure to mosquitoes (as assessed by a history of malaria) were not evident risk factors for either HIV or hepatitis B virus. AIDS in rural Africa seems to differ in its epidemiology from hepatitis B and appears to be spread predominantly by pre-existing patterns of heterosexual activity responsible for high rates of other sexually transmitted diseases.

AIDS Serodiagnosis↗
PubMed1988

A Ki-1 (CD30)-positive human cell line (Karpas 299) established from a high-grade non-Hodgkin's lymphoma, showing a 2;5 translocation and rearrangement of the T-cell receptor beta-chain gene.

We describe the characterization of a new human cell line, Karpas 299 (K299), established from blast cells in the peripheral blood of a 25-year-old white man. His illness, which began with enlarged occipital and axillary nodes and weight loss, ended after 7 months with generalized lymphadenopathy, pleural effusion, and bone marrow involvement. A lymph node biopsy showed a large cell lymphoma mainly sinusoidal in distribution. The blast cells with pleomorphic nuclei resembled primitive histiocytes. The cells, which expressed the T-cell-associated markers CD4 and CD5, were positive for HLA-DR, epithelial membrane antigen, and CD30 (Ki-1 antigen). The karyotype was aneuploid and included a translocation 2;5. The site of translocation on chromosome 5 (at 5q35.1) is in the region of the locus of the c-fms oncogene (receptor of the monocyte-macrophage colony-stimulating factor MCSF or CSF-1). The cell line Karpas 299 has the same karyotype and pattern of antigen expression as the patient's cells. Northern blot analysis of RNA showed an active rearrangement of the T-cell receptor beta-chain gene. This is to our knowledge the first Ki-1 antigen-positive line to be established from a case of non-Hodgkin's lymphoma.

Adult↗
PubMed1987

Use of Karpas HIV cell test to detect antibodies to HIV-2.

Commercial enzyme-linked immunosorbent assays for HIV-1 infection often fail to detect antibodies to HIV-2. A simplified version of the HIV cell test detects antibodies to this new virus and enables typing of HIV infections. Since sera from 3 macaque monkeys infected with simian immunodeficiency virus gave weakly positive reactions, this test holds promise for discovering any further strains of HIV that may exist or evolve.

Animals↗
PubMed1987

Studies of human retroviruses in relation to adult T-cell leukaemia, acquired immune deficiency syndrome, and multiple sclerosis.

Studies of adult T-cell leukaemia virus/human T-cell leukaemia/lymphotropic viruses (ATLV/HTLV-I) in Japan indicate that the virus is involved only with the development of ATL. By contrast, reports from the U.S.A. about HTLV have from time to time claimed that related HTLV are concerned not only with ATL of black persons, but also with a wide range of diseases, such as mycosis fungoides/Sezary's syndrome, T-cell hairy cell leukaemia, acquired immune deficiency syndrome (AIDS) and also multiple sclerosis. Using morphological, biological, serological and molecular hybridisation studies, we were able to confirm that the viruses implicated in the development of ATL and AIDS are distinct and that ATLV/HTLV-I is involved only in ATL, and HIV/LAV/HTLV-III only in AIDS. In vitro, ATLV/HTLV-I transformed and immortalised T-cells, while HIV/LAV/HTLV-III killed our T-cells. Failure to detect any serological cross-reaction indicates that all the structural proteins are different. Likewise, Southern blot studies failed to reveal any cross-hybridisation. Sixty patients with multiple sclerosis failed to reveal any association with ATLV/HTLV-I or with HIV/LAV/HTLV-III. Our conclusion is that ATLV/HTLV-I is involved only in ATL of Japanese and of some black persons of African origin, and that HIV/LAV/HTLV-III is associated only in AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Quantitative and qualitative analyses of serum antibodies elicited in adults by Haemophilus influenzae type b and pneumococcus type 6A capsular polysaccharide-tetanus toxoid conjugates.

Covalent binding to immunogenic proteins increases the immunogenicity of the capsular polysaccharides of Haemophilus influenzae type b (Hib) and pneumococcus type 6A (Pn6A). Conjugates composed of Hib, Pn6A, or the cross-reacting Escherichia coli K100 covalently bound to tetanus toxoid (TT) were injected into young adult volunteers. Local reactions were common and were probably due to Arthus reactivity mediated by the preexisting antibodies reacting with the TT component of the conjugates. Fever occurred in about 10% of the volunteers after the first injection; no volunteers had fever after the second injection. Similar levels of Hib or Pn6A antibodies were elicited by either 50- or 100-micrograms doses or by concurrent injection of two different conjugates (Hib-TT and Pn6A-TT or Hib-TT and K100-TT). The Hib-TT elicited about a 180-fold increase in Hib antibodies, and the Pn6A-TT conjugate elicited about an 8-fold increase in Pn6A antibodies after one injection. Booster reactions were not elicited in adults; similar levels of antibodies in the five experimental groups suggested that the responses elicited by the conjugates were maximal. A one-way cross-reaction was noted as Pn6A conjugates elicited rises of Hib antibodies in 13 of 20 volunteers; only 4 of 59 volunteers immunized with Hib-TT had increases in Pn6A antibodies. The preimmunization Hib antibodies were composed of immunoglobulin M (IgM), IgA, and IgG. The postimmunization sera showed an increase in all three isotypes; the elevation of the IgG was the highest of the three isotypes. Conjugate-induced antibodies to both the polysaccharide and TT exerted biological activities that have been correlated with immunity. Adsorption of the Hib-TT onto aluminium hydroxide resulted in higher levels and an earlier Hib antibody response in infant rhesus. These results encourage the evaluation of Hib and Pn6A conjugates in human children and infants.

Adjuvants, Immunologic↗
PubMed1985

Heterogeneity of T-cell beta-chain gene rearrangements in human leukaemias and lymphomas.

The state of T-cell receptor beta-chain gene rearrangement in human T-cell leukaemias has been analysed. All forms of leukaemia tested (T-CLL, ALL, PLL, Sezary syndrome and ATL) exhibit rearrangements of C beta genes confirming the clonality of these neoplasias. However we find no evidence for common gene rearrangements nor for restricted rearrangement patterns within this type of neoplasia. We find evidence of T-cells with C beta 1 and C beta 2 rearrangements, sometimes associated with Igh JH rearrangements, but several cases of T-cell leukaemia with a marker inversion of chromosome 14 (q11;q32) do not have Igh JH rearrangements. The results suggest that TCR beta gene rearrangement occurs early in T-cell ontogeny but that this rearrangement is most often irrelevant to leukaemogenesis.

Cell Line↗
PubMed1983

Hormone therapy for sexual dysfunction. The only "true aphrodisiac".

Human sexual behavior is extremely complex indeed. It has been described as the sum total of an individual's makeup, which includes chromosomal sex, gender identification, gonadal adequacy, rearing, environmental influences, hormonal factors, and possible hypothalamic sensitization. In recent years, much has been written about the importance of the psyche in matters of sex and about the mechanics of coitus, as well as the proper amatory prelude. The authors think the time is ripe for an assessment of how hormones modify sexual responsiveness. In particular, they hope this article will help to dispel the notion current in many circles that hormonal therapy is of little value.

Androgens↗
PubMed1983

Unusual virus produced by cultured cells from a patient with AIDS.

Cultured haemic cells from an AIDS patient were found to produce a morphologically new virus, not adult T-cell leukaemia virus (ATLV). Sera from 35 promiscuous homosexuals, 10 with and 25 without AIDS, did not have antibodies to ATLV (HTLV), but the sera of 6 of those patients reacted with cultured cells from the AIDS patient.

Acquired Immunodeficiency Syndrome↗
PubMed1982

Human myeloma cell line carrying a Philadelphia chromosome.

A new human plasmacytoma cell line (Karpas 707) has been established from a myeloma patient. The cultured cells are negative for Epstein-Barr viral nuclear antigen and free of mycoplasma. They are similar to plasma cells and secrete only lambda light chains. The cells are hypodiploid and contain the Philadelphia chromosome and other abnormalities. This cell line may be suitable for the production of human monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1982

Human plasmacytoma with an unusual karyotype growing in vitro and producing light-chain immunoglobulin.

A new human plasmacytoma line (Karpas 707) was established from the cells of the bone-marrow and peripheral blood of a patient with Bence-Jones-positive multiple myeloma. The cells of this line resembled the patient's malignant cells and fresh myeloma cells from nine other patients in being Epstein-Barr viral nuclear antigen negative. They looked like plasma cells and they secreted only lambda light chains. Both these cells and the patient's fresh cells were hypodiploid and contained the Philadelphia chromosome and several other markers. This line seems to be the first human plasmacytoma line since the IgE lambda-producing line (U266) established in 1968, and it may be suitable for the production of human monoclonal antibodies.

Antibodies, Monoclonal↗
PubMed1982

The differential ultrastructural localization of immunoglobulin heavy and light chains in human haematopoietic cell lines.

The ultrastructural localization of immunoglobulin heavy and light chains has been investigated in nine haematopoietic cell lines, using a technique which involves the treatment of lightly prefixed cells with saponin to allow penetration of the antibody-peroxidase conjugate. The synthesis and secretion of immunoglobulin was also studied in these cell lines. Immunoglobulin was found to be localized in the cisternae and on the membranes of the rough endoplasmic reticulum, perinuclear space and/or Golgi apparatus. In each case staining for heavy chains was weak or absent in the perinuclear space while staining for light chains was usually strong. Additionally in three cell lines immunoperoxidase staining indicated that heavy chains were absent from the Golgi apparatus despite the observed presence of light chains in the Golgi apparatus and the secretion of combined immunoglobulin into the supernatant. The results obtained suggest compartmentalization of the synthesis of light and heavy chains and indicate that the technique of immunoelectron microscopy may significantly contribute to an understanding of the mechanisms involved in immunoglobulin synthesis, intracellular transport and secretion.

Cell Compartmentation↗
PubMed1981

Purification and physicochemical characterization of a human cytotoxic factor produced by a human haemic cell line.

A cytotoxic factor, produced by a human lymphoblastoid cell line [Karpas (1977) Br. J. Cancer 35, 152--160; Karpas (1977) Br. J. Cancer 36, 437--445], was purified both from the cell extracts and from the culture medium containing the cell lysate, by using ammonium sulphate precipitation, DEAE-cellulose chromatography, gel filtration and affinity chromatography on concanavalin A--Sepharose and on [3H]amino-ethanol--glass beads. Two factors, Factor I and Factor II, were separated by DEAE-cellulose chromatography. Factor I was eluted from this column at 30 mM-aminoethanol/HCl buffer, pH 8.0, whereas Factor II was bound strongly to DEAE-cellulose and was eluted only at 325 mM-aminoethanol/HCl buffer, pH 8.0. The purified Factor I migrated as a single band on polyacrylamide-gel electrophoresis. Its isoelectric point, pI, was 8.0 +/- 0.3. Its sedimentation coefficient, S20,w, was 3.5 +/- 0.1 S and its apparent molecular weight, Mr, was 65 000 +/- 1000 as determined by sedimentation-velocity and sedimentation-equilibrium measurements. A linear relationship between molecular weight and concentration was found in equilibrium runs, suggesting a non-spherical shape of the molecule. Factor I is not a glycoprotein, inasmuch as it does not bind to concanavalin A--Sepharose. It consists of two subunits (Mr 32 000 +/- 4000), migrating on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis as a single band. Factor II had pI 6.0 +/- 0.4 and Mr 75 000 +/- 3000. Factors I and II are thus different proteins.

Cell Line↗
PubMed1981

In vitro radiosensitivity of human leukemia cell lines.

The in vitro radiobiologic survival values (n, D0) of four tumor lines derived from human hematopoietic tumors were studied. These cell lines were HL50 (n = 1.3, D0 = 117 rad[1.17 Gy]), promyelocytic leukemia; K562 (n = 1.4, D0 = 165 rad[1.65 Gy]), erythroleukemia; 45 (n = 1.1, D0 = 147 rad[1.47 Gy]), acute lymphocyte leukemia; and 176 (n = 4.0, D0 = 76 rad[0.76 Gy]), acute monomyelogenous leukemia. More cell lines must be examined before the exact relationship between in vitro radiosensitivity and clinical radiocurability is firmly established.

Cell Line↗