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Biomedical subjects

R T Mitsuyasu

Publications and source records attributed to R T Mitsuyasu.

At least 55 records · Page 3Linked to original sources
PubMed1990

The use of myeloid hematopoietic growth factors in patients with HIV infection.

Hematologic abnormalities are frequent occurrences in patients with HIV infection. Myelosuppression in AIDS may be due to multiple factors and has significant impact on the treatment of HIV-infected individuals, as it is the major dose-limiting toxicity of a number of antimicrobial compounds and chemotherapy. Both granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) are hematopoietic hormones which effect myeloid progenitor cells and enhance the function of mature neutrophils. Clinical studies of the effects of these agents in patients with AIDS indicate that GM-CSF and G-CSF can increase the production of leukocytes in a dose-dependent fashion. This increase in leukocyte production may allow the continued administration of full doses of antiviral or other myelosuppressive medications in previously hematologically intolerant patients with AIDS. Investigations of the hematopoietic, virologic, and immunologic effects of these agents alone and in combination with other hematopoietins, cytokines, and chemotherapeutic agents will ultimately define their clinical utility in patients with HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1990

AIDS Kaposi sarcoma-derived cells produce and respond to interleukin 6.

Cell lines derived from Kaposi sarcoma lesions of patients with AIDS (AIDS-KS cells) produce several cytokines, including an endothelial cell growth factor, interleukin 1 beta, and basic fibroblast growth factor. Since exposure to human immunodeficiency virus increases interleukin 6 (IL-6) production in monocytes and endothelial cells produce IL-6, we examined IL-6 expression and response in AIDS-KS cell lines and IL-6 expression in AIDS Kaposi sarcoma tissue. The AIDS-KS cell lines (N521J and EKS3) secreted large amounts of immunoreactive and biologically active IL-6. We found both IL-6 and IL-6 receptor (IL-6-R) RNA by slot blot hybridization analysis of AIDS-KS cells. The IL-6-R was functional, as [3H]thymidine incorporation by AIDS-KS cells increased significantly after exposure to human recombinant IL-6 (hrIL-6) at greater than 10 units/ml. When AIDS-KS cells (EKS3) were exposed to IL-6 antisense oligonucleotide, cellular proliferation decreased by nearly two-thirds, with a corresponding decrease in the production of IL-6. The decrease from IL-6 antisense in AIDS-KS cell proliferation was reversed by the addition of hrIL-6. We confirmed that AIDS-KS cells produced IL-6 in vivo by preparing RNA and tissue sections from involved and uninvolved skin from a patient with AIDS Kaposi sarcoma. We detected immunoreactive IL-6 in the involved tumor areas and to a lesser extent in the surrounding normal epidermis. Slot blot hybridization showed a great excess of IL-6 and IL-6-R RNA in involved skin compared to uninvolved skin. These results show that both IL-6 and IL-6-R are produced by AIDS-KS cells and that IL-6 is required for optimal AIDS-KS cell proliferation, and they suggest that IL-6 is an autocrine growth factor for AIDS-KS cells.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Gamma-interferon-induced monocyte major histocompatibility complex class II antigen expression individuals with acquired immune deficiency syndrome.

Twelve patients with the acquired immune deficiency syndrome (AIDS) and Kaposi's sarcoma were treated with recombinant human gamma-interferon (rIFN-gamma). A rapid, substantial increase in the fraction of HLA-DQ-positive monocytes was noted after treatment with rIFN-gamma. The rIFN-gamma-induced increase in monocyte HLA-DQ was seen throughout the course of treatment, with the percentage of HLA-DQ-positive monocytes dropping slightly following each week's treatment with rIFN-gamma and then rapidly increasing following the next course of treatment. Although the percentage of HLA-DR-positive monocytes was unchanged (HLA-DR was expressed on greater than 80% of monocytes prior to treatment), the density of HLA-DR on monocytes also increased following rIFN-gamma treatment. Following rIFN-gamma treatment, no changes were seen in CD3, CD4, CD8 T cell numbers, in T cell subset ratio (CD4/CD8), in Leu 7 or CD16 (Leu 11) cell number, in spontaneous Ig secretion, in PHA-induced in vitro proliferation, or in NK activity. These results indicate that exposure to rIFN-gamma in vivo led to the increased expression of class II antigens on monocytes in patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Cross-sectional study of reverse transcriptase-inhibiting antibody as a marker of acquired immune deficiency syndrome.

A cross-sectional study of 128 individuals infected with human immunodeficiency virus type 1 (HIV-1) was conducted to determine the correlation of reverse transcriptase-inhibiting (RTI) antibody to clinical disease. Thirty-two individuals were studied in each of four clinical groups: asymptomatic individuals, those with persistent generalized lymphadenopathy, those with acquired immune deficiency syndrome (AIDS)-related complex, and those with AIDS. Our study showed that 78% of asymptomatic individuals, 53% of those with persistent generalized lymphadenopathy, 50% of those with AIDS-related complex, and only 25% of those with AIDS have RTI antibody. Concurrent measurement of measles antibody level was used as an indicator of the immune status of these individuals. Measles antibody did not decline in persons with clinical disease, but asymptomatic individuals had lower antibody titers, possibly due to hypergammaglobulinemia associated with advanced HIV infection. These results indicate that more HIV-infected asymptomatic individuals than symptomatic individuals have RTI antibody. This suggests either that the RTI antibody level decreases with the progression of disease in HIV infection or that symptomatic individuals do not produce RTI antibody. The presence or absence of RTI antibody can thus be used as a marker of advanced disease.

AIDS-Related Complex↗
PubMed1989

Clinical role of granulocyte-macrophage colony-stimulating factor.

The activity of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) for increasing leukocyte production and enhancing mature neutrophil function has been clearly demonstrated in phase I clinical trials in patients with a variety of hematologic and malignant diseases. The focus of current studies includes determination of optimal administration schedules and its use in combination with myelosuppressive chemotherapy, radiation therapy or antimicrobial agents. The utility of GM-CSF as a stimulant of host defense against infections and tumors is also under study.

Acquired Immunodeficiency Syndrome↗
PubMed1989

The relationship between medical and psychological status in newly diagnosed gay men with AIDS.

We assessed current medical and psychological status in 50 homosexual/bisexual males who were within 3 months of the diagnosis of AIDS. Subjects had typically impaired cellular immunity, relatively well-maintained physical performance capacity, and reported surprisingly good current health status, in spite of significant numbers of medical symptoms. While as a group they reported moderate levels of psychological distress, intact self-esteem, and a high quality of life, a significant minority reported high psychological distress, low self-esteem, and low quality of life. Psychological distress was correlated with subjective, but not objective, measures of current health status.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Intravenous recombinant tumor necrosis factor in the treatment of AIDS-related Kaposi's sarcoma.

Tumor necrosis factor (TNF) has demonstrated antitumor activity against a variety of tumors and is particularly cytotoxic to capillary endothelial cells, which are the presumed cell of origin of Kaposi's sarcoma. We evaluated the toxicity and clinical antitumor and antiretroviral effects of recombinant TNF administered at a once weekly dose of 100 micrograms/m2 intravenously for 8 weeks in five men with AIDS-related Kaposi's sarcoma and without prior opportunistic infection. One patient was removed from study at week 4 due to rapid progression of Kaposi's sarcoma, another patient with stage IV disease and a pretreatment CD4 count of 11 developed fever, hypotension, and pneumonia at week 7 and died 8 days after discontinuing recombinant TNF. No pathogenic organisms were isolated. He had marked eschar formation of his Kaposi's sarcoma lesions, particularly in areas previously exposed to radiation therapy. Uniform toxicities included fevers, rigors, and headaches during drug infusion that were ameliorated by prophylactic meperidine hydrochloride and acetaminophen. All experienced fatigue and three had arthralgias. One patient had transient hypotension which corrected with i.v. fluids. No significant hematologic, hepatic, or renal toxicities were seen. All patients had some progression of their Kaposi's sarcoma on study. There was no change in CD4 or CD8 count or in CD4:CD8 ratios. Serum human immunodeficiency virus (HIV) p24 antigen levels increased greater than 50% in three patients. We conclude that, as a single agent, at a dose of 100 micrograms/m2 recombinant TNF by i.v. infusion has no obvious antitumor or antiretroviral effects in patients with AIDS-related Kaposi's sarcoma.

Acquired Immunodeficiency Syndrome↗
PubMed1988

AIDS-related Kaposi's sarcoma: a review of its pathogenesis and treatment.

One of the most unusual manifestations of the acquired immunodeficiency syndrome is the cutaneous tumor, Kaposi's sarcoma. This rare and indolent tumor was once thought of as an interesting curiosity in Europe and Africa prior to the recognition of AIDS. Currently, however, this tumor accounts for approximately one quarter of all cases of AIDS recognized in the United States, and while not the proximate cause of death in most cases, Kaposi's sarcoma may cause severe physical and psychological morbidity in many patients. Treatment approaches must incorporate an understanding of the severe immunologic impairment in these individuals as well as their relatively poor tolerance to the myelosuppressive effects of many therapeutic agents. Treatment for Kaposi's sarcoma includes chemotherapy and radiation therapy, and more recently antiretroviral agents and immunomodulators in patients with indolent disease. Prophylactic treatment for Pneumocystis carinii pneumonia as well as nutritional and psychological support, and pain control are also important aspects of the care of these patients. This review will focus on the pathogenesis and natural history of Kaposi's sarcoma and review the treatment approaches and limitations of therapy for this tumor.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Granulocyte-macrophage colony-stimulating factor enhances neutrophil function in acquired immunodeficiency syndrome patients.

We conducted a clinical trial of human recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) in leukopenic patients with acquired immunodeficiency syndrome (AIDS) and analyzed neutrophil function before, during, and after in vivo administration of rGM-CSF. Prior to GM-CSF infusion, AIDS patients' neutrophil superoxide generation and neutrophil antibody-dependent cell-mediated cytotoxicity were enhanced normally by in vitro exposure to GM-CSF. Neutrophil phagocytosis and intracellular killing of Staphylococcus aureus were also normal in the majority of these patients. Two patients, however, had discrete neutrophil functional defects: one in phagocytosis and one in intracellular killing. During the period of GM-CSF infusion, these abnormalities were corrected. The number of circulating neutrophils increased in all patients treated with GM-CSF in a dose-dependent manner. Neutrophils produced in vivo in response to GM-CSF administration functioned normally and there was evidence for neutrophil priming and activation in vivo. We conclude that GM-CSF treatment of AIDS patients leads to the production of functionally active neutrophils, suggesting therapeutic potential for GM-CSF in the treatment of patients with impaired host defense.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Immunomodulating effects in vitro of interleukin-2 and interferon-gamma on human blood and bone marrow mononuclear cells.

Mononuclear cells (MNC) derived from peripheral blood (PBMNC) of 23 normal donors and 4 AIDS patients, and from bone marrow (BMMNC) of 15 normal donors were incubated at 37 degrees C in culture medium alone or in the presence of either natural or recombinant human interleukin-2 (IL-2) or recombinant human interferon-gamma (IFN-gamma; 1-1,000 U/ml). The cultured cells were washed on days 1, 4 or 7 and tested for various immune functions in vitro and for cell surface phenotype. IL-2, but not IFN-gamma, was found mitogenic for both PBMNC and BMMNC. The natural killer (NK) activity of both PBMNC and BMMNC was the only function tested that was markedly augmented (over 100-fold compared to medium control) by both lymphokines. Pretreatment of PBMNC with IL-2 at greater than or equal to 10 U/ml profoundly suppressed (up to 90%) various functions, such as mitogenic responses (phytohemmagglutinin, concanavalin A, pokeweed mitogen), allogeneic mixed leukocyte reaction, antibody production and T cell colony formation in agar. In contrast, some BMMNC functions were elevated at low doses of IL-2 and IFN-gamma, and significant suppression of BMMNC was seen only with high doses of IL-2 (greater than or equal to 100 U/ml) and IFN-gamma (1,000 U/ml). IL-2 was by far more effective than IFN-gamma in both the amplification of NK activity and the suppression of most of the other functions. IL-2, but not IFN-gamma, was found to activate/induce suppressor cells and increased the proportion of Leu-2+ (CD8) cells in PBMNC; the suppressive effect was time- and dose-dependent. The IL-2-induced suppression could be diminished by inclusion of anti-IL-2 antibody during the pretreatment phase. Similar suppressive effects were noted in PBMNC from AIDS patients. These findings suggest that: (a) high-dose IL-2 may elicit immunosuppression which can be mediated by nondiscriminative highly cytotoxic cells (i.e. lymphokine-activated killer cells) and/or by noncytotoxic, nonspecific suppressor cells, and (b) that PBMNC respond differently to the lymphokines than do BMMNC.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Kaposi's sarcoma in the acquired immunodeficiency syndrome.

Kaposi's sarcoma is the most common malignancy seen in association with AIDS. Although the pathogenesis of AIDS-KS has not been clearly established, the clinical course and prognosis are closely related to the patient's immune status, prior history of opportunistic infection, and hematologic status. Treatment methods include local or regional radiation therapy, cytotoxic chemotherapy, and interferon therapy. Evaluation of the results of clinical therapeutic studies in this tumor should consider its natural history and peculiar biologic behavior and associated complications of AIDS. Effective treatment strategy would take into account the immune status of the patient, the rate of progression of tumor, the presence or risk of developing life-threatening opportunistic infections, associated hematologic or neurologic abnormalities, the toxicities of treatment, and the desire of the patient for treatment. Investigations of antiviral, antiproliferative, and immunomodulating agents singly or in combination currently are in progress. Additionally innovative approaches with biologic response modifies, adjunctive hematopoietins, and growth factor modulators may lead to newer approaches to the control of this malignancy.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Potential role of granulocyte-macrophage colony stimulating factor in patients with HIV infection.

Abnormalities in leukocyte number and function contribute to the high incidence of infection in patients with HIV infection. Leukopenia is a frequent occurrence in patients with AIDS and AIDS-related diseases and is a major dose limiting factor in the treatment of HIV infected individuals with antiviral compounds and chemotherapy. Granulocyte-macrophage colony stimulating factor (GM-CSF) is a hematopoietic hormone that stimulates the growth and differentiation of myeloid progenitor cells in vitro and enhances the function of mature monocytes and neutrophils. Studies on the effects of this agent in patients with AIDS, indicate that GM-CSF causes increased production of neutrophils, monocytes, and eosinophils in a dose dependent fashion. Leukocytes produced in response to GM-CSF function normally as judged by in vitro tests. The effects of GM-CSF on HIV replication and expression in vivo are uncertain. Studies of the use of GM-CSF alone and in combination with antiretroviral, antimicrobial, antineoplastic agents or other hematopoietins and cytokines will help define its ultimate clinical utility in patients with HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Effect of recombinant human granulocyte-macrophage colony-stimulating factor on myelopoiesis in the acquired immunodeficiency syndrome.

We administered recombinant (biosynthetic) human granulocyte-macrophage colony-stimulating factor (GM-CSF) to 16 patients with the acquired immunodeficiency syndrome (AIDS) and leukopenia (2225 +/- 614 cells per microliter [mean +/- SD]). Each patient first received a single intravenous dose; 48 hours later a 14-day continuous intravenous infusion of the agent was begun. The doses used were 1.3 X 10(3) (n = 4), 2.6 X 10(3) (n = 4), 5.2 X 10(3) (n = 4), 1.0 X 10(4) (n = 3), or 2.0 X 10(4) (n = 1) U per kilogram of body weight per day. Administration of recombinant GM-CSF resulted in dose-dependent increases in circulating leukocytes and in increases in circulating neutrophils, eosinophils, and monocytes. The peak leukocyte count ranged from 4575 +/- 2397 cells per microliter at the lowest dose, to 48,700 in the patient receiving the highest dose. Mild side effects--low-grade fever, myalgia, phlebitis, and flushing--were observed in some patients; there were no life-threatening toxic reactions. Our data demonstrate that recombinant human GM-CSF is well tolerated and biologically active in leukopenic patients with AIDS. Strategies to increase the number and function of circulating leukocytes may reduce the morbidity and mortality of infections in these and other patients with leukopenia.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Infection with the human immunodeficiency virus (HIV) is associated with an in vivo increase in B lymphocyte activation and immaturity.

The expression of phenotypic markers on B lymphocytes in patients with the acquired immune deficiency syndrome (AIDS), in human immunodeficiency virus (HIV) seropositive individuals, and in healthy seronegative donors was examined by two-color flow cytometry. Patients with AIDS and HIV-seropositive individuals showed an elevated percentage of B cells bearing an activation marker, the transferrin receptor, when compared with donors not infected with HIV. A decrease in the percentage of resting (Leu-8 positive) B cells was also seen in AIDS patients and HIV-seropositive individuals. An increased percentage of circulating, immature (CALLA-positive, CD10) B cells was seen in AIDS patients. These phenotypic changes were accompanied by an increased level of spontaneous IgG and IgM secretion, and increased cell size within the total B cell population and in some B cell subpopulations, in patients with AIDS and in HIV-seropositive people. These results demonstrate that phenotypic changes indicative of in vivo B cell activation and immaturity accompany the polyclonal production of Ig seen in HIV-infected individuals.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Early effects of HIV on CD4 lymphocytes in vivo.

Low circulating CD4 cell numbers and CD4 cell dysfunction are distinguishing features of HIV-mediated disease. The current study delineates the in vivo effects of HIV on distinct functional subsets of CD4 cells in homosexually active men who have been infected with HIV for different lengths of time, and examines the capacity of lymphocytes from these men to proliferate in vitro in response to soluble antigen. Although peripherial blood mononuclear cells from most acquired immune deficiency syndrome (AIDS) patients did not proliferate in response to either tetanus toxoid or Candida albicans, cells from most HIV seropositive men without AIDS, many of whom had been infected for more than 18 mo, responded normally to both. Non-responsiveness in HIV-infected men without AIDS was a late event and was associated with longer duration of infection, lower CD4 cell numbers, and subsequent development of AIDS. A defect in this response was observed in only one of 19 HIV seropositive men whose CD4 levels were greater than 300/mm3, but in eight of 10 with levels less than 300/mm3. The defect could not be attributed to a selective depletion of defined CD4 subpopulations that respond to soluble antigen. Dual-color immunofluorescent flow cytometry indicated that 4B4+, 2H4-, and HB-11- CD4 cells were not lost at a faster rate than other CD4 subsets.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Dual infection of the central nervous system by AIDS viruses with distinct cellular tropisms.

Human immunodeficiency virus (HIV) is the causative agent of the acquired immune deficiency syndrome (AIDS). A large number of AIDS patients show evidence of neurologic involvement, known as AIDS-related subacute encephalopathy, which has been correlated with the presence of HIV in the brain. In this study, two genetically distinct but related viruses were isolated from one patient from two different sources in the central nervous system: brain tissue and cerebrospinal fluid. Both viruses were found to replicate in peripheral blood lymphocytes, but only virus from brain tissue will efficiently infect macrophage/monocytes. The viruses also differ in their ability to infect a brain glioma explant culture. This infection of the brain-derived cells in vitro is generally nonproductive, and appears to be some form of persistent or latent infection. These results indicate that genetic variation of HIV in vivo may result in altered cell tropisms and possibly implicate strains of HIV with glial cell tropism in the pathogenesis of some neurologic disorders of AIDS.

Acquired Immunodeficiency Syndrome↗