Biomedical subjects

A M Levine

Publications and source records attributed to A M Levine.

At least 19 recordsLinked to original sources

PubMed2003

Different localization of dendritic cell reservoirs in human immunodeficiency virus-1 subtype B versus subtype E-infected lymph nodes.

The presence of p24 protein was studied in lymph nodes from human immunodeficiency virus (HIV)-positive patients affected by persistent generalized lymphadenopathy. Paraffin-embedded lymph node sections from 50 HIV-1 subtype E-infected lymph nodes from patients in Thailand and 25 HIV-1 presumably subtype B-infected lymph nodes from patients in the United States were immunostained with p24 HIV major core and capsid monoclonal antibodies using the streptavidin-biotin immunoperoxidase technique. Positivity for HIV p24 protein was detected in 20 of 22 HIV-1 subtype B infected nodes in which lymphoid follicles were present, with p24 staining demonstrating a reticular pattern within the germinal centers. Interestingly, no case from 50 clade E-infected lymph nodes containing lymphoid follicles had such a reticular pattern in the germinal centers. This difference could be explained by differential infection of subsets of dendritic cells by the two HIV-1 clades, or perhaps by different routes of initial HIV-1 transmission.

Biopsy↗

PubMed2002

Transduction of acute myeloid leukemia cells with third generation self-inactivating lentiviral vectors expressing CD80 and GM-CSF: effects on proliferation, differentiation, and stimulation of allogeneic and autologous anti-leukemia immune responses.

Acute myeloid leukemia (AML) patients treated with available therapies achieve remission in approximately 60% of cases, but the long-term event-free survival is less than 30%. Use of immunotherapy during remission is a potential approach to increase survival. We propose to develop cell vaccines by genetic modification of AML cells with CD80, an essential T cell costimulator that is lacking in the majority of AML cases, and GM-CSF, to induce proliferation and activation of professional antigen-presenting cells. Here, we evaluated third generation self inactivating (SIN) lentiviral vectors, which have the potential advantage of improved safety. CD80 and GM-CSF expression by these vectors was higher than that reported with second generation vectors (Stripecke et al, Blood 2000; 96: 1317-1326). In some cases, endogenous GM-CSF expression by transduced AML cells induced phenotypic changes consistent with the maturation of leukemia blasts into antigen-presenting cells. Further, in all cases studied, GM-CSF expression was associated with higher proliferation and cell viability. Allogeneic and autologous mixed lymphocyte reactions performed with transduced irradiated AML cells expressing CD80 and/or GM-CSF demonstrated that expression of either transgene enhanced T cell activation. These pre-clinical data demonstrate the potential feasibility of third generation SIN vectors for use in AML immunotherapy.

Acute Disease↗

PubMed2002

Immunotherapy with acute leukemia cells modified into antigen-presenting cells: ex vivo culture and gene transfer methods.

Adult patients with acute leukemia have, in general, a poor prognosis, with long-term, disease-free survival achieved in only approximately one-third of cases. One of the proposed mechanisms for this poor overall response is the inability of the immune system to detect and eliminate residual malignant leukemia cells, which subsequently serve as a source of leukemic relapse. This review discusses the rationale of immunotherapy for acute leukemia and presents in vitro and in vivo model systems that were devised for pre-B acute lymphocytic leukemia (ALL) and acute myeloid leukemia (AML). New advances in the ex vivo manipulation of acute leukemia cells are presented, which attempt to modify these cells into functional antigen-presenting cells. These cells can then be used as autologous vaccines at the time of minimal residual disease after standard chemotherapy, to stimulate host immune responses against their own leukemia cells. The various approaches toward this aim include incubation of leukemia cells with cytokines or growth factors and gene manipulation of these cells. In particular, ex vivo culture of ALL cells with CD40 ligand, incubation of AML cells with granulocyte-macrophage colony-stimulating factor and interleukin-4 (GM-CSF/IL-4) and lentiviral transduction of ALL and AML cells for expression of immunomodulators (CD80 and GM-CSF) are current approaches under investigation for the development of autologous acute leukemia cell vaccines.

Acute Disease↗

PubMed2001

High-dose cytosine-arabinoside and cisplatin regimens as salvage therapy for refractory or relapsed AIDS-related non-Hodgkin's lymphoma.

No effective salvage regimen has been defined for patients with AIDS-related non-Hodgkin's lymphoma (AIDS-NHL) who do not respond to first-line chemotherapy that contains anthracycline. Combined dexamethasone, cytosine arabinoside, and cisplatin (DHAP) and etoposide, methylprednisolone, cytosine arabinoside, and cisplatin (ESHAP) have shown good response rates in HIV-negative patients with relapsed lymphomas. We retrospectively analyzed patients with refractory or relapsed AIDS-NHL who had been treated with either DHAP or ESHAP to evaluate the feasibility and efficacy of these regimens. Twenty-six patients with refractory or relapsed AIDS-NHL were treated between 1990 and 1999 either with DHAP ( n = 13) or with ESHAP ( n = 13). Only 1 patient from each group (8%) had achieved complete remission with any previous therapy, and most had progressive disease after the regimen immediately preceding DHAP or ESHAP. In the ESHAP group, 4 patients (31%) achieved complete remission (CR) and 3 patients (23%) attained partial remission (PR) for an overall response rate of 54%. The median survival was 7.1 months (range, 1-58.9+ months) from the time ESHAP was begun. Among the 3 patients with primary refractory lymphoma, there was 1 CR, 1 PR, and one patient with stable disease. In contrast, only 1 PR (7%) was observed with DHAP; the median survival was 3 months. Myelosuppression was the most significant toxicity with grade 4 neutropenia occurring in all who received ESHAP and in 54% of patients treated with DHAP. Neutropenic fever occurred in 8 (62%) ESHAP-treated and 6 (46%) DHAP-treated patients. Although hematologic toxicity is profound, ESHAP appears to be an active salvage regimen for patients with relapsed or refractory AIDS-NHL.

Adult↗

PubMed2001

Clinical, immunologic, and pathologic correlates of bone marrow involvement in 291 patients with acquired immunodeficiency syndrome-related lymphoma.

Bone marrow involvement is reported in approximately 25% of patients with newly diagnosed acquired immunodeficiency syndrome-related lymphoma (ARL). Studied were 291 patients with ARL, diagnosed and treated at one medical center between 1984 and 1998. Clinical, immunologic, and pathologic characteristics of patients with bone marrow involvement were compared with those of patients without marrow involvement. Bone marrow involvement was present in 55 patients (19%). Small noncleaved lymphoma was diagnosed in 38% of the entire group and was the most common pathologic subtype in patients with bone marrow involvement (55% versus 34%; P =.008). Analysis of complete blood counts revealed a median hemoglobin level of 10.6 g/dL in both marrow-positive and marrow-negative groups. In contrast, a platelet count lower than 100 000/microL was more common in patients with bone marrow involvement (27% versus 11%; P =.02). Patients with marrow involvement were more likely to have leptomeningeal (cerebrospinal fluid [CSF]) lymphoma than patients whose marrows were uninvolved (24% versus 7%; P <.001) and were also more likely to have high lactate dehydrogenase (LDH) (P =.002), bone involvement (P <.001), and/or systemic B symptoms including fever, night sweats, and/or weight loss (P =.05). Median survival did not differ between marrow-positive and marrow-negative groups. On multivariate analysis, factors associated with decreased survival of marrow-positive patients included greater than 50% involvement (P =.002), systemic B symptoms (P =.008), and high-grade histologic type (P =.035). Marrow involvement in ARL correlates with small noncleaved pathology, thrombocytopenia lower than 100 000 mm(3), high LDH, and lymphomatous involvement of the CSF. Survival is statistically shorter in patients with greater than 50% marrow involvement, high-grade pathology, and/or systemic B symptoms.

Adult↗

PubMed2001

Human herpesvirus 8 infection and Kaposi's sarcoma among human immunodeficiency virus-infected and -uninfected women.

Little is known about the epidemiology of human herpesvirus 8 (HHV-8) infections among women. A cross-sectional study was conducted of HHV-8 infection among human immunodeficiency virus (HIV)-infected and high-risk HIV-uninfected women. Serological tests with noninduced (latent) and induced (lytic) HHV-8 antigens were used to detect infection among 2483 participants of a multisite cohort. Reactivity to latent antigen was present in 4.1% and to induced antigens in 12.0% of women. Seven of 8 women who reported Kaposi's sarcoma had HHV-8 antibodies. Among HIV-positive women, HHV-8 infection was associated with use of crack, cocaine, or heroin (76% vs. 65%; P<.001), past syphilis (29% vs. 20%; P<.001), an injection drug-using male sex partner (61% vs. 53%; P=.014), black race (P=.010), and enrollment site (P=.015). In multivariate analysis, HIV infection, older age, past syphilis, black race, and enrollment site were independently associated with HHV-8 infection. In this cohort of North American women, HHV-8 infection was associated with HIV infection, drug use, and risky sexual behavior.

Adult↗

PubMed2001

Reproductive factors and risk of intermediate- or high-grade B-Cell non-Hodgkin's lymphoma in women.

PURPOSE: The incidence rates of non-Hodgkin's lymphoma (NHL) unrelated to human immunodeficiency virus infection are lower for women than for men; yet, few factors have been identified that may account for this difference in risk. NHL is difficult to study epidemiologically because this disorder represents a group of malignancies that differ in terms of morphologic presentation, immunologic features, genetic characteristics, prognosis, and etiology. PATIENTS AND METHODS: We conducted a population-based case-control study in women to determine whether reproductive factors or hormonal exposures might be related to the risk of high- or intermediate-grade B-cell NHL. We interviewed 177 female residents of Los Angeles County who were diagnosed with high- or intermediate-grade B-cell NHL between 1989 and 1992; each case patient was individually matched on age and race to a control subject who lived in her neighborhood. RESULTS: Women who had used oral contraceptives had significantly lower risk of intermediate- or high-grade NHL (multivariate odds ratio [OR] = 0.47; 95% confidence interval [CI], 0.26 to 0.86) than women who had never used these compounds. Among parous women, those who had used lactation suppressants (which contain high levels of estrogen) had significantly lower risk of NHL (multivariate OR = 0.50; 95% CI, 0.29 to 0.85) than unexposed women. Postmenopausal women had a somewhat greater risk of NHL than premenopausal women, whereas those postmenopausal women who had used hormone replacement therapy (HRT) (primarily estrogen) had somewhat lower risk than those who had not used HRT. CONCLUSION: Exogenous estrogens seem to have a protective effect on the risk of high- and intermediate-grade B-cell NHL. Although the mechanisms for such protection are not known, alterations in immune reactivity, cytokine expression, or B-cell modulation may play a role.

Adult↗

PubMed2001

Prevalence and correlates of anemia in a large cohort of HIV-infected women: Women's Interagency HIV Study.

Anemia is a common manifestation of HIV infection, occurring in approximately 30% of patients with asymptomatic infection and in as many as 75% to 80% of those with AIDS. Anemia has been associated with decreased quality of life and decreased survival. We performed a cross-sectional study nested within a multicenter prospective cohort study to describe the prevalence of anemia in 2056 HIV-infected and 569 HIV-negative women as well as to define the demographic, clinical, immunologic, and virologic correlates of anemia among HIV-infected women. A total of 37% of HIV-positive women and 17% of HIV-negative women had hemoglobin levels < 12 g/dl (p < .001). Factors associated with anemia in HIV-positive and HIV-negative women included mean corpuscular volume (MCV) < 80 fl (p < .001) and black race (p < .001). Among HIV-infected women, multivariate logistic analyses revealed that African American race (p < .0001), MCV < 80 fl (p < .0001), CD4 count < 200 per microliter (p <.0001), higher HIV RNA in plasma (p = .02), current use of ZDV (p = .01), and history of clinical AIDS (p = .004) were all independent predictors of anemia. These data indicate that worsening parameters of HIV disease are associated with anemia among HIV-infected women. Black women and women with low MCV values are at increased risk for anemia independent of HIV status.

Adolescent↗

PubMed2001

Clinical aspects and management of AIDS-related Kaposi's sarcoma.

AIDS-related Kaposi's sarcoma (KS) is a tumour of vascular endothelium, which is seen predominantly in men who have sex with men. The majority of affected individuals have advanced immunosuppression at the time of the initial KS diagnosis. The disease may present with cutaneous lesions, or with involvement of visceral organs, of which the gastrointestinal tract is most common. KS may also present with lymphoadenopathy or with isolated lymphoedema, even in the absence of cutaneous lesions. Affected individuals are uniformly co-infected with HIV and with Human Herpesvirus type 8 (HHV8). HHV8 is present within KS tissues, and is aetiological in the pathogenesis of disease, along with aberrant cytokine expression, production of multiple angiogenic peptides, and immune dysregulation. While not presently curable, multiple treatment options exist and must be evaluated in terms of the specific needs of the individual patient. Various local therapies are aimed at eradicating small lesions, while acknowledging that the KS in general, or its likelihood of recurring will be unaffected. Systemic chemotherapy is used to treat extensive visceral involvement. Knowledge of the pathogenesis of disease has led to the development of novel treatment strategies, aimed at HHV8 as the target of therapy, or at the inflammatory cytokine or angiogenic milieu necessary for KS growth. Use of highly active anti-retroviral therapy, aimed at controlling the underlying HIV infection, has been associated with a dramatic decrease in the incidence of KS, and may also be useful in the treatment of existing KS disease.

Angiogenesis Inhibitors↗

PubMed2001

Liposomal daunorubicin in the treatment of relapsed or refractory non-Hodgkin's lymphoma.

PURPOSE: To assess the efficacy and toxicity of liposomal daunorubicin administered as a two-hour intravenous infusion to patients with relapsed or refractory non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Eligible patients had relapsed or refractory NHL with measurable or evaluable disease, and low grade, select intermediate grade, or mantle cell pathologic types. Prior exposure to an anthracycline or anthracenedione was allowed. Liposomal daunorubicin at a dose of 100 mg/m2 was given intravenously over a minimum of 120 minutes every 3 weeks. as a single agent. RESULTS: Thirty-three patients were accrued: twenty-three (70%) had low-grade histologies; six (18%) had intermediate-grade histologies (follicular large-cell and diffuse small cleaved); and four (12%) patients had mantle-cell lymphoma. Eighteen (55%) had received two or more prior regimens; fourteen (42%) received a prior anthracycline. A median of six cycles of liposomal daunorubicin were administered (range 1-15). Of 31 patients evaluable for response, 2 complete and 10 partial remissions were documented for a major response rate of 39% (95% confidence interval (CI): 22%-58%). The median duration of response was 19.5 months (range 4.3-41.1+). Six responders (50%) had received a prior anthracycline; one responder had mantle-cell histology. The major toxicities were grade 3 or 4 neutropenia in 26 patients (79%), mild to moderate nausea in 22 (67%), and fatigue in 16 (48%). CONCLUSIONS: Liposomal daunorubicin at 100 mg/m2 every three weeks has activity in patients with relapsed or refractory NHL, including patients with prior exposure to an anthracycline. Further studies of liposomal daunorubicin in combination with other agents are warranted.

Adult↗

PubMed2001

Hematologic Aspects of HIV/AIDS.

This review addresses various aspects of HIV infection pertinent to hematology, including the consequences of HIV infection on specific aspects of hematopoiesis and an update on the current biologic, epidemiologic and therapeutic aspects of AIDS-related lymphoma and Hodgkin's disease. The results of the expanding use of progenitor cell transplantation in HIV infected patients are also reviewed. In Section I, Dr. Scadden reviews the basis for HIV dysregulation of blood cell production, focusing on the role of the stem cell in HIV disease. T cell production and thymic function are discussed, with emphasis placed upon the mechanisms of immune restoration in HIV infected individuals. Results of clinical and correlative laboratory studies are presented. In Section II, Dr. Levine reviews the recent epidemiologic trends in the incidence of lymphoma, since the widespread availability of highly active anti-retroviral therapy (HAART). The biologic aspects of AIDS-lymphoma and Hodgkin's disease are discussed in terms of pathogenesis of disease. Various treatment options for these disorders and the role of concomitant anti-retroviral and chemotherapeutic intervention are addressed. Drs. Zaia and Krishnan will review the area of stem cell transplantation in patients with AIDS related lymphoma, presenting updated information on clinical results of this procedure. Additionally, they report on the use of gene therapy, with peripheral blood CD34+ cells genetically modified using a murine retrovirus, as a means to treat underlying HIV infection. Results of gene transfer experiments and subsequent gene marking in HIV infected patients are reviewed.

Acquired Immunodeficiency Syndrome↗

PubMed2001

Sea urchin goosecoid function links fate specification along the animal-vegetal and oral-aboral embryonic axes.

We have identified a single homolog of goosecoid, SpGsc, that regulates cell fates along both the animal-vegetal and oral-aboral axes of sea urchin embryos. SpGsc mRNA is expressed briefly in presumptive mesenchyme cells of the approximately 200-cell blastula and, beginning at about the same time, accumulates in the presumptive oral ectoderm through pluteus stage. Loss-of-function assays with morpholine-substituted antisense oligonucleotides show that SpGsc is required for endoderm and pigment cell differentiation and for gastrulation. These experiments and gain-of-function tests by mRNA injection show that SpGsc is a repressor that antagonizes aboral ectoderm fate specification and promotes oral ectoderm differentiation. We show that SpGsc competes for binding to specific cis elements with SpOtx, a ubiquitous transcription activator that promotes aboral ectoderm differentiation. Moreover, SpGsc represses transcription in vivo from an artificial promoter driven by SpOtx. As SpOtx appears long before SpGsc transcription is activated, we propose that SpGsc diverts ectoderm towards oral fate by repressing SpOtx target genes. Based on the SpGsc-SpOtx example and other available data, we propose that ectoderm is first specified as aboral by broadly expressed activators, including SpOtx, and that the oral region is subsequently respecified by the action of negative regulators, including SpGsc. Accumulation of SpGsc in oral ectoderm depends on cell-cell interactions initiated by nuclear beta-catenin function, which is known to be required for specification of vegetal tissues, because transcripts are undetectable in dissociated or in cadherin mRNA-injected embryos. This is the first identified molecular mechanism underlying the known dependence of oral-aboral ectoderm polarity on intercellular signaling.

Amino Acid Sequence↗

PubMed2001

Incidence and management of AIDS-related lymphoma.

Over time, the spectrum of the acquired immune deficiency syndrome (AIDS) epidemic has changed, especially with the advent of highly active antiretroviral therapy (HAART). The goal of this article is to delineate changes occurring in the incidence and management of lymphoma over the course of the AIDS epidemic. Lymphoma usually occurs rather late in the course of human immunodeficiency virus (HIV) infection and is the cause of death in up to 20% of HIV-infected individuals. It is seen in all population groups at risk for HIV and is more common in men than in women. It is usually diagnosed in patients with markedly decreased CD4 cell counts, consistent with prolonged periods of HIV infection and subsequent immunosuppression. Recent data from several large series have demonstrated a substantial decline in the median CD4 cell count among patients with newly diagnosed AIDS-related lymphoma despite the recent widespread use of HAART. While still somewhat controversial, use of HAART has generally not produced a significant decline in the incidence of AIDS-related lymphoma. Patients treated with low-dose vs standard-dose chemotherapy for AIDS-related lymphoma have achieved similar response and survival rates, although standard-dose therapy is associated with greater toxicity. Adapting therapy to prognostic factors has not produced a significant improvement in survival. Use of antiretroviral therapy along with chemotherapy appears safe, and may be associated with longer survival. An infusional regimen called EPOCH (etoposide, prednisone, vincristine [Oncovin], cyclophosphamide, doxorubicin HCl) shows promise in the future management of AIDS-related lymphoma. No regimen is currently considered the standard of therapy for patients with relapsed AIDS-related lymphoma, and survival is short in this setting.

Antineoplastic Agents↗

PubMed2000

Evolving characteristics of AIDS-related lymphoma.

Over time, the epidemiologic and demographic characteristics of AIDS have changed in the United States, while the use of highly active antiretroviral therapy has changed the natural history of the disease. The goal of the study was to ascertain any changes in the epidemiologic, immunologic, pathologic, or clinical characteristics of AIDS-related lymphoma (ARL) over the course of the AIDS epidemic. Records of 369 patients with ARL diagnosed or treated at a single institution from 1982 through 1998 were reviewed. Single institutional data were compared to population-based data from the County of Los Angeles. Significant changes in the demographic profile of patients with newly diagnosed ARL have occurred, with the later time intervals associated with a higher prevalence in women (P =.25), in Latino/Hispanic individuals (P <.0001), and in those who acquired human immunodeficiency virus (HIV) heterosexually (P =.01). These changes were similar in both countywide, population-based analyses and in those from the single institution. The median CD4(+) lymphocyte count at lymphoma diagnosis has decreased significantly over the years, from 177/dL in the earliest time period (1982-1986), to 53/dL in the last time period from 1995 to 1998 (P =.0006). The pathologic spectrum of disease has also changed, with a decrease in the prevalence of small noncleaved lymphoma (P =.0005) and an increase in diffuse large cell lymphoma (P <.0001). Despite changes in the use of antiretroviral or chemotherapy regimens, the median survival has not significantly changed.

AIDS-Related Opportunistic Infections↗

PubMed2000

Chemotherapy consisting of doxorubicin, bleomycin, vinblastine, and dacarbazine with granulocyte-colony-stimulating factor in HIV-infected patients with newly diagnosed Hodgkin's disease: a prospective, multi-institutional AIDS clinical trials group study (ACTG 149).

To ascertain the results of standard ABVD chemotherapy (doxorubicin, bleomycin, vinblastine, dacarbazine) in HIV-infected patients with newly diagnosed Hodgkin's disease (HD), a nonrandomized, prospective, multiinstitutional clinical trial was conducted by the AIDS Clinical Trials Group (ACTG), in HIV-infected patients with Hodgkin's disease. All patients received the standard ABVD regimen, with granulocyte-colony-stimulating factor (G-CSF). Antiretroviral therapy was not used. Between May, 1992 and August, 1996, 21 patients were added to the study and treated. The median CD4 count was 113 cells/mm3, and 29% had a history of a clinical AIDS-defining condition before diagnosis of HD. Systemic "B" symptoms were present in 90% at diagnosis. Stage IV HD was present in 67%, with bone marrow involvement in 12 (57%). Nodular sclerosis HD was present in 38%, with mixed cellular disease in 31%. Among all patients entered and treated, complete remission (CR) was attained in 9 (43%; 90% confidence interval [CI], 24%-63%), whereas partial response occurred in 4 (19%), leading to an overall objective response rate of 62% (90% CI, 42%-79%). Despite routine use of G-CSF, 10 patients (47.6%) experienced life-threatening neutropenia, with absolute neutrophil counts <500 cells/mm3. In all, nine opportunistic infections occurred in 6 patients (29%) during the study or shortly thereafter. Median survival was 1.5 years. Results of this study suggest that alternative treatment strategies should be explored, including use of chemotherapy together with antiretroviral therapy.

Adult↗

PubMed2000

Factors associated with incident self-reported AIDS among women enrolled in the women's interagency HIV study (WIHS). WIHS Collaboratorive Study Group.

We evaluated factors associated with incident self-reported AIDS diagnoses among HIV-infected women in the Women's Interagency HIV Study (WIHS). Baseline information included age, race/ethnicity, HIV risk category, site of enrollment, years of education, cigarette smoking, CD4 cell count, and HIV viral load. Baseline and follow-up data on self-reported AIDS were analyzed using chi-square, Kaplan-Meier, and Cox proportional hazard models. Among the 1397 HIV-infected women who reported being free of clinical AIDS at baseline, 335 women (24%) reported an incident AIDS diagnosis during follow-up. In stratified Kaplan-Meier analyses, the development of self-reported AIDS was significantly associated with baseline CD4 cell count and viral load (p<0.01). In multivariate Cox proportional hazard analyses, women were statistically more likely to report AIDS if they had CD4 cell counts below 195 cells/mm3 (p<0.01), HIV RNA >4000 copies/ml (p<0.01), were current smokers (p<0.01), and had "no identifiable risk" for acquisition of HIV (p = 0.03). Self-reports of a clinical AIDS diagnosis may not always be accurate, but laboratory markers of HIV disease indicate that those women who self-report such diagnoses have greater immunodeficiency and a higher viral load when compared with those who report no AIDS-defining diagnoses.

Acquired Immunodeficiency Syndrome↗

PubMed2000

All-trans-retinoic acid effects the growth, differentiation and apoptosis of normal human myeloid progenitors derived from purified CD34+ bone marrow cells.

We have previously shown that all-trans retinoic acid (ATRA) increases the number of CFU-GM colonies grown from unseparated human bone marrow cells with crude sources of colony stimulating factors. In this study, we further characterized the effect of ATRA on the growth of CFU-GM stimulated by individual cytokines from multiple samples of CD34+ enriched or purified human bone marrow cells. The number of IL-3- or GM-CSF-induced CFU-GM with 3 x 10(-7) M ATRA was 3.25+/-1.13, and 2.17+/-0.8-fold greater respectively, compared to controls without ATRA, while G-CSF had no effect and the ratio of colony-induced with or without ATRA was 1.06+/-0.17 (P = 0.00012). No colonies grew with ATRA + IL-6 or ATRA without a cytokine. Maximum enhancing effect on IL-3-induced CFU-GM occurred when ATRA was added on day 2, gradually diminished when delaying ATRA, and in cultures of day 9 or older adding ATRA had no effect. In 14 days liquid cultures of purified CD34+ cells with IL-3, ATRA increased the number of myeloid differentiated cells to 91-95%, compared to 37-70% with IL-3 alone. In addition, the number of apoptotic cells using the annexin V method increased after 14 days from 5.1% with IL-3 to 17.1% with IL-3 + ATRA and by the TUNEL in situ method from 10-26% to 60-95%, respectively. This study demonstrates that ATRA consistently enhances the growth of myeloid progenitors from CD34+ cells. This effect is dependent on the stimulating cytokine, suggesting the myeloid cells responding to ATRA are the less mature CFU-GMs that are targets of IL-3 and GM-CSF and not the G-CSF-responding mature progenitors. The growth stimulation by ATRA and IL-3 is also associated with granulocyte differentiation and increased apoptosis. These studies further suggest a potential role of pharmacological doses of ATRA on the development of normal human hematopoietic cells.

Antigens, CD34↗

PubMed2000

Acquired immunodeficiency syndrome-related lymphoma: clinical aspects.

While the widespread use of highly active antiretroviral therapy (HAART) has led to substantial decreases in the incidence of opportunistic infections and Kaposi's sarcoma, a major decrease in lymphoma has not yet occurred. Patients with acquired immunodeficiency syndrome (AIDS)-related lymphoma present with widespread, extranodal disease, often in the presence of systemic "B" symptoms. Factors associated with decreased survival include age greater than 35 years, history of injection drug use, poor performance status, CD4 cell count less than 100/dL, a history of AIDS prior to the diagnosis of lymphoma, stage III or IV disease, and/or elevated lactate dehydrogenase (LDH) levels. Low-dose combination chemotherapy has been associated with complete remission (CR) rates of 41% to 46%, with an overall median survival time of 8.7 months, similar to results achieved with standard-dose therapy, which is associated with greater toxicity. Infusional regimens have been associated with CR rates as high as 94%, and further evaluation is justified. Combination chemotherapy may be given safely with HAART. Treatment of relapsed AIDS-related lymphoma remains problematic.

Acquired Immunodeficiency Syndrome↗