ENV-specific cytotoxic T lymphocyte responses in HIV seronegative health care workers occupationally exposed to HIV-contaminated body fluids.

Identification of the components of protective immunity are crucial for the development of effective prophylactic and therapeutic vaccine strategies. Analysis of HIV-specific responses in exposed but uninfected individuals might thus provide a unique resource to elucidate the components and correlates of protective immunity to HIV. In the present study we analyzed HIV-specific cytotoxic and helper T lymphocyte responses in health care workers (HCW) exposed to body fluids from HIV-positive individuals. HCW exposed to blood from HIV-negative individuals as well as healthy donors served as controls. Cytotoxic T lymphocyte (CTL) responses to HIV envelope (env) peptides were detected in 7/20 (35%) HCW exposed to HIV-positive blood and in none of the 20 health care workers exposed to uninfected blood or the seven healthy blood donors studied. HIV-specific CTL responses were detected only after in vitro stimulation, and were MHC class I restricted. No MHC class I restriction elements were uniformly identified among the different responders. 21/28 (75%) HCW exposed to contaminated blood responded to env as measured by IL-2 production to the peptides, in contrast to only 9/38 (24%) HCW exposed to HIV seronegative blood and 3/35 (9%) healthy blood donors. All the HIV exposed individuals were seronegative on repeated ELISA tests, and no evidence of infection was obtained by PCR analysis. These findings indicate that a single exposure to HIV can induce CTL immunity to HIV antigens, in the absence of other evidence of infection.

Regression of oral hairy leukoplakia during zidovudine therapy.

We describe two patients with human immunodeficiency virus infection and oral hairy leukoplakia whose tongue lesions resolved on oral zidovudine therapy. During therapy, each patient had a measurable reduction in human immunodeficiency virus antigen corresponding with clinical regression of oral lesions. The clinical course suggests that zidovudine may have contributed to the resolution of these lesions either indirectly through immunologic improvement or through an antiviral effect.

Erythema nodosum associated with acute cytomegalovirus mononucleosis in an adult.

Acute cytomegalovirus mononucleosis has been associated with maculopapular rashes, petechiae, purpura, urticaria, ulcerative lesions, and vesicular eruptions. Although erythema nodosum has been reported in association with a number of infectious and noninfectious diseases, to our knowledge it has not been associated with cytomegalovirus infections. We report the first case of an adult patient with acute cytomegalovirus mononucleosis who presented with erythema nodosum.

Acute myocardial infarction diagnosed by myoglobinuria.

Myoglobin can be found in excess in the urines of some patients with acute myocardial infarction. To test the specificity of this finding, urine specimens were analyzed from 39 patients with provisional diagnosis of myocardial infarction by means of a hemagglutination-inhibition technique with prepared antisera to monkey myoglobin. Of 24 patients with subsequently documented myocardial infarction, 15 had at least one positive determination. None of the 15 patients without infarction had positive tests. Ten of 13 patients with infarction studied within 24 hours of the initial event had positive reactions. The percentage of positive reactions in the infarct group decreased sharply after the first 24 hours. This technique may be of value in rapid screening of patients with possible acute myocardial infarction during early stage of symptoms.

Successful treatment of acquired immunodeficiency syndrome-related Mycobacterium avium complex disease with a multiple drug regimen including amikacin.

Disease due to Mycobacterium avium complex (MAC) in patients with the acquired immunodeficiency syndrome (AIDS) typically occurs late in the course of AIDS and is usually disseminated with evidence of multiorgan involvement. Most patients are persistently bacteremic. Previously published studies have noted a poor response to antimycobacterial chemotherapy. We describe successful treatment of MAC disease in an AIDS patient with a multiple drug regimen, including amikacin, clofazimine, rifampin, ethambutol, and ciprofloxacin. This patient, whose presentation and MAC disease course distinctly differ from most published experience, remains clinically and microbiologically MAC-disease free 25 months after initiation of therapy. We describe four additional AIDS patients with MAC disease who had a favorable clinical and microbiological response to this regimen without developing serious adverse effects after periods ranging from 4 to 12 months. We suggest a prospective, controlled clinical trial using this regimen for treatment of MAC disease in patients with AIDS may be warranted.

Racial differences in care among hospitalized patients with Pneumocystis carinii pneumonia in Chicago, New York, Los Angeles, Miami, and Raleigh-Durham.

BACKGROUND: While strategies for medical care for human immunodeficiency virus-related Pneumocystis carinii pneumonia (PCP) are well established, racial variations in care have not been evaluated. OBJECTIVE: To determine whether sociodemographic characteristics influence patterns of care and patient outcomes, by analyzing the use of diagnostic tests and anti-PCP medications and in-hospital mortality rates for persons who were hospitalized with human immunodeficiency virus-related PCP. METHODS: Retrospective chart review of a cohort of 627 Veterans Administration (VA) patients and 1547 non-VA patients with empirically treated or cytologically confirmed PCP who were hospitalized from 1987 to 1990. Outcomes included representative aspects of the process of care for PCP and short-term mortality rates. RESULTS: Among VA patients, black and Hispanic patients were not significantly different from white patients with regard to in-hospital mortality rates, use and timing of a bronchoscopy, or receipt of timely anti-PCP medications. Among non-VA patients, black and Hispanic patients were more likely to die in the hospital and less likely to undergo a diagnostic bronchoscopy in the first 2 days of hospitalization. These racial and ethnic group differences in the use of a bronchoscopy and in-hospital mortality among non-VA patients were almost fully accounted for by differences in health insurance status and hospital characteristics. CONCLUSIONS: Racial factors do not appear to be an important determinant of the intensity of diagnostic or therapeutic care among patients who are hospitalized with PCP. Variations in care are largely attributable to differences in health insurance and admitting hospital characteristics.

Guidelines for the treatment of cytomegalovirus diseases in patients with AIDS in the era of potent antiretroviral therapy: recommendations of an international panel. International AIDS Society-USA.

OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included.

2',5'-oligoadenylate synthetase, neopterin and beta 2-microglobulin in asymptomatic HIV-infected individuals.

This study examined 2',5'-oligoadenylate (2,5A) synthetase activity in 26 individuals during the asymptomatic phase of HIV infection and its correlation with neopterin or beta 2-microglobulin. In HIV-antibody-positive (HIV-Ab+) asymptomatic people, both neopterin and beta 2-microglobulin levels in sera were significantly elevated; in contrast, 2,5A-synthetase activity in peripheral blood mononuclear cells was not significantly higher than in HIV-antibody-negative controls. The 2,5A-synthetase levels in symptomatic people (AIDS-related complex and AIDS) were significantly higher than in either asymptomatic or control individuals. However, within the group of HIV-infected asymptomatic individuals, all three markers were positively correlated. In this group, neopterin values were negatively correlated with the number of CD4+ lymphocytes while a positive correlation was found between 2,5A-synthetase and the number of CD8+ lymphocytes. Asymptomatic people with detectable serum HIV p24 antigen had significantly higher 2,5A-synthetase, neopterin, beta 2-microglobulin and number of CD8+ lymphocytes. This study suggests that elevated 2,5A-synthetase activity may reflect a different aspect of host response to HIV infection than do elevated neopterin or beta 2-microglobulin.

Immunologic and virologic evaluation after influenza vaccination of HIV-1-infected patients.

OBJECTIVE: The present study was designed to determine the effect of immune activation, achieved by influenza vaccination, on plasma HIV RNA levels and immunological parameters including CD4 cell levels, antigen-stimulated T-cell function and apoptotic death of peripheral blood mononuclear cells. DESIGN AND METHODS: Thirty-four HIV-infected individuals and nine uninfected controls were immunized with influenza vaccine and blood was collected at weeks 0, 2, 4 and 16. Plasma was isolated and used for HIV RNA and influenza-specific antibody qualifications. CD4 cell counts, activation and maturation markers of T-lymphocyte subsets were determined by flow cytometry. In vitro T-helper responses, spontaneous- and activation-induced cell death assays were also performed. RESULTS: Influenza-specific humoral and cellular immune responses correlated with CD4 count. Only in patients with CD4 counts > 300 x 10(6)/l there was a modest increase in T-cell responses to influenza virus, which was less than control subjects, observed after vaccination. Immunization had no significant effect on CD4 counts or plasma viral levels in the HIV-positive patients. Baseline apoptosis inversely correlated with CD4 counts and directly correlated with viral load. Activation-induced apoptosis did not change appreciably after vaccination and spontaneous apoptosis increased only in the < 300 CD4 group. CONCLUSION: These results indicate that immune stimulation resulting from influenza vaccination did not significantly change the levels of plasma virus, CD4 cell counts, or activation-induced apoptosis in HIV-infected individuals, although an increase in the T-cell response to influenza and spontaneous apoptosis was observed in the > 300 and < 300 CD4 groups, respectively.

ABT-378/ritonavir plus stavudine and lamivudine for the treatment of antiretroviral-naive adults with HIV-1 infection: 48-week results.

OBJECTIVE: To evaluate the safety and antiviral activity of different dose levels of the HIV protease inhibitor ABT-378 combined with low-dose ritonavir, plus stavudine and lamivudine in antiretroviral-naive individuals. DESIGN: Prospective, randomized, double-blind, multicenter. METHODS: Eligible patients with plasma HIV-1 RNA > 5000 copies/ml received ABT-378 200 or 400 mg with ritonavir 100 mg every 12 h; after 3 weeks stavudine 40 mg and lamivudine 150 mg every 12 h were added (group I, n = 32). A second group initiated treatment with ABT-378 400 mg and ritonavir 100 or 200 mg plus stavudine and lamivudine every 12 h (group II, n = 68). RESULTS: Mean baseline HIV-1 RNA was 4.9 log10 copies/ml in both groups and CD4 cell count was 398 x 10(6)/l and 310 x 10(6)/l in Groups I and II respectively. In the intent-to-treat (ITT; missing value = failure) analysis at 48 weeks, HIV-1 RNA was < 400 copies/ml for 91% (< 50 copies/ml, 75%) and 82% (< 50 copies/ml, 79%) of patients in groups I and II respectively. Mean steady-state ABT-378 trough concentrations exceeded the wild-type HIV-1 EC50 (effective concentration to inhibit 50%) by 50-100-fold. The most common adverse events were abnormal stools, diarrhea and nausea. No patient discontinued before 48 weeks because of treatment-related toxicity or virologic rebound. CONCLUSIONS: ABT-378 is a potent, well-tolerated protease inhibitor. The activity and durable suppression of HIV-1 observed in this study is probably attributable to the observed tolerability profile and the achievement of high ABT-378 plasma concentrations.

Antigen-stimulated apoptotic T-cell death in HIV infection is selective for CD4+ T cells, modulated by cytokines and effected by lymphotoxin.

OBJECTIVE: To characterize the mechanism of in vitro antigen-induced apoptotic T-cell death in the peripheral blood mononuclear cells (PBMC) of HIV-1-infected individuals. DESIGN AND METHODS: PBMC from HIV-1 infected and uninfected individuals were unstimulated or stimulated with HIV-1 envelope synthetic peptides (Env) or influenza A virus to determine the extent of antigen-stimulated apoptotic T-cell death, whether this death was limited to the CD4+ subset, and the effects of cytokines on T-cell death. Death was assessed by apoptotic nuclear morphology after 7 days of culture by fluorescence microscopy using a DNA-specific dye. Transwell cultures and supernatant transfers were utilized to test whether a soluble factor produced by HIV-positive PBMC induced death of HIV-negative T cells. Exogenous cytokines [interleukin (IL)-12, interferon (IFN)-gamma, IL-4 and IL-10], as well as antibodies against endogenously produced cytokines (IL-4, IL-10, IL-12, and lymphotoxin) were tested for their ability to modulate death. RESULTS: Antigenic stimulation induced death in PBMC from HIV-positive donors, but not in PBMC from HIV-negative donors. Antigen-stimulated death was seen in CD4+ but not CD8+ T-cell subset from the HIV-positive patients. Apoptotic death was blocked by IL-12, IFN-gamma, anti-IL-4, anti-IL-10, and anti-lymphotoxin, but not by anti-IL-12. Transwell and supernatant transfer experiment indicated that antigen-stimulated HIV-positive PBMC produced a factor that killed T-cell blasts. The factor was inhibited by anti-lymphotoxin, but not by anti-IL-10. CONCLUSIONS: Stimulation of HIV-positive PBMC with CD4-dependent antigens results in selective death of CD4+ T cells that is modulated by cytokines. Our results suggest that apoptotic death is not limited to HIV-infected or HIV-specific T cells, but occurs in bystander cells. Lymphotoxin is a mediator of antigen-stimulated T-cell death in this in vitro model.

Incorporation of zidovudine into leukocyte DNA from HIV-1-positive adults and pregnant women, and cord blood from infants exposed in utero.

OBJECTIVE: The nucleoside analog 3'-azido-3'-deoxythymidine (ZDV) has widespread clinical use but also is carcinogenic in newborn mice exposed to the drug in utero and becomes incorporated into newborn mouse DNA. This pilot study was designed to determine ZDV incorporation into human blood cell DNA from adults and newborn infants. DESIGN: In this prospective cohort study, peripheral blood mononuclear cells (PBMC) were obtained from 28 non-pregnant adults and 12 pregnant women given ZDV therapy, six non-pregnant adults with no exposure to ZDV, and six non-pregnant adults who last received ZDV > or = 6 months previously. In addition, cord blood leukocytes were obtained from 22 infants of HIV-1-positive, ZDV-exposed women and from 12 infants unexposed to ZDV. There were 11 mother-infant pairs involving HIV-1 -positive women. METHODS: DNA was extracted from PBMC obtained from non-pregnant HIV-1-positive adults taking ZDV, pregnant HIV-1-positive women given ZDV during pregnancy, and from adults not taking ZDV. Cord blood leukocytes were examined from infants exposed to ZDV in utero and from unexposed controls. DNA samples were assayed for ZDV incorporation by anti-ZDV radioimmunoassay (RIA). RESULTS: The majority (76%) of samples from ZDV-exposed individuals, pregnant women (8 of 12), non-pregnant adults (24 of 28), or infants at delivery (15 of 22), had detectable ZDV-DNA levels. The range of positive values for ZDV-treated adults and infants was 25-544 and 22-452 molecules ZDV/10(6) nucleotides, respectively. Analysis of 11 mother-infant pairs showed variable ZDV-DNA incorporation in both, with no correlation by pair or by duration of drug treatment during pregnancy. Two of the 24 samples from individuals designated as controls were positive by anti-ZDV RIA. The 20-fold range for ZDV-DNA values in both adults and infants suggested large interindividual differences in ZDV phosphorylation. CONCLUSIONS: Incorporation of ZDV into DNA was detected in most of the samples from ZDV-exposed adults and infants. Therefore, the biologic significance of ZDV-DNA damage and potential subsequent events, such as mutagenicity, should be

Issues in combination antiretroviral therapy: a review.

High viral burden and replication persist during all phases of human immunodeficiency virus (HIV) disease. Although monotherapy has yielded considerable benefits, these benefits are neither absolute nor durable. Combination therapy has multiple goals: to reduce viral replication and burden; to relieve drug toxicity; to attenuate viral mutations leading to resistance and possibly to conversion from non-syncytium-inducing to syncytium-inducing virus; and to broaden the spectrum of specific cells and tissues in which antiretroviral agents are active. At present, zidovudine remains the cornerstone of antiretroviral monotherapy and combination therapy. A partial list of agents tried in combinations with and without zidovudine includes the nucleoside analogues zalcitabine and didanosine; non-nucleoside reverse-transcriptase inhibitors (nevirapine, delavirdine, atevirdine, pyridinones, TIBO derivatives); protease inhibitors; inhibitors of viral regulatory functions (tat inhibitors); cytokine antagonists; acyclovir; and colony-stimulating factors. The rationales, the regimens, and the results all vary. We usually recommend combination therapy for treatment-naive patients who are asymptomatic with < 200 CD4+ cells/mm3 or who are symptomatic, and for patients who have been receiving zidovudine monotherapy and who are stable but whose CD4+ counts have fallen to < 300 cells/mm3, or who are progressing. In the absence of definitive results from clinical trials of combination therapy, the decision to embark on this route remains to be made between each individual patient and the practitioner.

Predictors of outcome in AIDS patients receiving zidovudine.

Fifty-eight AIDS patients who previously had Pneumocystis carinii pneumonia (PCP) were enrolled in an open trial of zidovudine therapy. We analyzed baseline clinical and laboratory parameters to identify predictors of outcome. Fifty-eight patients were followed for a mean of 26.5 weeks. There were 17 deaths; the probability of survival at 24 weeks was 0.81. Forty-one participants had unsuccessful outcomes, which included new opportunistic infections (24), progressive neurologic deterioration (2), and drug toxicity, excluding anemia, necessitating discontinuation of zidovudine (15). Only 24 subjects (41%) were receiving zidovudine at the end of the study period including 17 who had neither opportunistic infection nor toxicity. Low baseline hemoglobin level (p less than 0.001) and poor performance status as measured by the Karnofsky scale (p less than 0.01) independently predicted unsuccessful outcome and early death. Low hemoglobin (p = 0.001), low platelet count (p = 0.016), and increased time since PCP (p = 0.008) predicted development of drug toxicity. Neither CD4 lymphocyte count nor p24 antigenemia correlated with outcome.

Detection of HIV-1 provirus in bronchoalveolar lavage cells by polymerase chain reaction.

This study was undertaken to evaluate whether HIV-seropositive individuals harbor HIV provirus in cells obtained by bronchoalveolar lavage (BAL). BAL cells were obtained from 14 HIV-positive patients undergoing bronchoscopy for evaluation of acute pulmonary symptoms. Cells were fractionated into macrophage-enriched and lymphocyte-enriched populations. The quantity of HIV-1 proviral DNA in the unfractionated BAL cells and in each population of fractionated cells was determined following polymerase chain reaction (PCR) amplification. Detectable quantities (3-90 copies/100,000 cells) of HIV-1 proviral DNA were found in unfractionated BAL cells in 12 of 14 patients. In the other two patients, provirus was detected after a sevenfold enrichment of lymphocytes. Provirus was also detected in BAL macrophages from 8/14 patients although proviral content was significantly higher in the lymphocyte fraction (133 +/- 72 vs. 35 +/- 22 proviral copies, p = 0.03). No correlation was seen with the ability to detect provirus in lymphocyte- or macrophage-enriched fractions and clinical diagnosis (e.g., Pneumocystis carinii pneumonia). The data suggest that lymphocytes are the predominant cells that contain provirus found in the lungs, although macrophages may be infected in some patients.

Pneumocystis carinii choroiditis in patients with AIDS: clinical features, response to therapy, and outcome.

To further characterize the clinical features, response to therapy, and outcome of Pneumocystis carinii choroiditis in patients with AIDS, we retrospectively reviewed the course of choroiditis for eight patients identified from two institutions through April 1991. Seven patients had prior Pneumocystis carinii pneumonia and had received aerosolized pentamidine prophylaxis for a median of 10 months; one patient had no prior history of pneumonia or prophylaxis. The median CD4+ lymphocyte count for six patients was 11 cells/mm3. Choroiditis was a preterminal diagnosis for three patients--two with associated disseminated pneumocystosis. Ocular manifestations improved or resolved with therapy for five of the six treated patients. All five subsequently received prophylaxis with dapsone (n = 2), dapsone/trimethoprim (n = 2), or aerosolized pentamidine (n = 1). Choroiditis recurred at 15 months in the one patient receiving aerosolized pentamidine. The median survival from time of diagnosis was 44 weeks. A literature review including an additional 40 cases support the conclusions that (a) Pneumocystis choroiditis is a rare complication of advanced HIV disease, occurring often in the context of systemic pneumocystosis; (b) ocular signs and symptoms may improve or resolve with specific antipneumocystis therapy; and (c) relapse may occur, particularly in those not receiving systemic prophylaxis.

Immune response to human immunodeficiency virus (HIV) in healthcare workers occupationally exposed to HIV-contaminated blood.

Exposure to human immunodeficiency virus (HIV) does not necessarily induce infection or seroconversion defined by standard criteria based on enzyme-linked immunosorbent assay (ELISA), Western Blot, or polymerase chain reaction (PCR) techniques, but it can induce HIV-specific cell-mediated immune responses. Healthcare workers (HCWs) occupationally exposed to HIV represent a unique population with low-level exposure to HIV for whom time and type of exposure are specifically recorded. Although the frequency of seroconversion in HCWs occupationally exposed to HIV contaminated body fluids is relatively low, a higher proportion of HIV-exposed HCWs seem to exhibit in vitro cellular responses to HIV envelope peptides. Our findings indicate that parenteral exposure to HIV can induce cell-mediated immune responses in the absence of seroconversion. The significance of these responses is not known, but it is possible that the low incidence of HIV infection after exposure might be due, in part, to a protective cellular immune response to low HIV inocula.

Anti-CCR5 antibodies in sera of HIV-positive individuals.

One of the proposed mechanisms for resistance to human immunodeficiency virus-1 (HIV-1) infection is the presence of antibodies against receptor for CC-chemokines (CCR5). These antibodies, detected in sera of uninfected individuals exposed to HIV, have been shown to downmodulate surface CCR5 in vivo and are able to neutralize the infectivity of CCR5 strains in vitro. To address the potential role of anti-CCR5 antibodies in HIV infection, we analyzed anti-CCR5 antibody levels in plasma from HIV-infected patients who present a wide range of CD4(+) T-cell counts and viral load. Increased levels of anti-CCR5 antibodies were found in plasma from 13/46 HIV-positive donors compared with healthy controls (0/36). However, antibody levels were not associated with disease stage evaluated by CD4(+) T-cell counts and viral load.

T cell responses to recall antigens, alloantigen, and mitogen of HIV-infected patients receiving long-term combined antiretroviral therapy.

The effect of highly active antiretroviral therapy (HAART) on T cell responses in 30 HIV-infected patients was studied. Lymphocyte proliferation in response to influenza A virus, HIV-1 p24, gp160, allogeneic leukocytes, and mitogen, as well as influenza-specific cytotoxic T lymphocyte (CTL) responses, were measured. AIDS patients had decreased T cell-proliferative responses to influenza and alloantigen compared with asymptomatic patients. Absence of positive proliferative responses of HIV-infected patients to HIV-1 antigens was not associated with increased interleukin 10 production. Correlation was observed between influenza-specific CTL response and T cell proliferation, as well as CD4+ T lymphocyte counts, indicating the importance of CD4+ helper T cells for generating antiviral CTL responses. Finally, these results show that HAART-treated asymptomatic patients, but not AIDS patients, have T cell responses comparable to those of control individuals. It remains to be determined whether immune-based therapy will contribute any additional benefit to patients who received HAART.

Effect of zidovudine postexposure prophylaxis on the development of HIV-specific cytotoxic T-lymphocyte responses in HIV-exposed healthcare workers.

We evaluated the effects of zidovudine postexposure prophylaxis (PEP) on the development of human immunodeficiency virus (HIV) envelope-specific cytotoxic T-lymphocyte responses in 20 healthcare workers with occupational exposures to HIV. Seven healthcare workers were treated with zidovudine PEP. Only 1 of 7 treated, versus 6 of 13 not treated, developed an HIV envelope-specific cytotoxic T-lymphocyte response. These data suggest that zidovudine abrogated HIV-specific cytotoxic T-lymphocyte responses. HIV-specific cytotoxic T-lymphocyte responses may be useful as a surrogate marker of HIV replication in the evaluation of new regimens for PEP of occupational HIV exposures.