Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The biological markers for determining as early as possible the progression in the infection by the human immunodeficiency virus (HIV) are very important for the health care of patients, and to adapt their anti-retroviral treatment. Among those, four independent biological markers for predicting a pejorative evolution in the following 36 months are used in medical practice: two specific for HIV, p24 antigenemia and serum titre of antibodies to the p24 core antigen, and two non-HIV specific surrogate markers, the beta 2-microglobulinemia and the absolute number of CD4 T cell in blood. P24 antigenemia corresponds to an active retroviral in vivo replication. The cut off for detection is about 10 pg/ml. It is difficult to detect in black people, and in the asymptomatic or pauci-symptomatic stages of the disease. The apparition or the increase of the serum p24 antigen levels suggest the occurrence of opportunistic infections. P24 antigenemia decreases or disappears during the treatment by zidovudine. The diminution or the disappearance of serum antibodies directed to the p24 core protein are secondary to the deficiency of the humoral immunity, and to an increase of the viral replication, which occur at the late stage of the disease. The diminution or the disappearance of serum antibodies to p24 precede the occurrence of AIDS by several months. The increase of the serum beta 2-microglobulin level is associated with the severity of the disease. In the San Francisco prospective cohort, the progression to AIDS in 36 months was 69% when beta 2-microglobulinemia was more than 5 mg/l, 33% when it was between 3.1 to 5 mg/l, and 12% when it was less than 3 mg/l. The beta 2-microglobulin intra-thecal synthesis level could serve as a marker for the specific HIV encephalitis. The CD4 lymphocyte count constitutes an independent provisional marker for progression to AIDS, probably the most important, but mainly of statistical value. A lymphocyte count of 200 CD4/mm3 is considered as the threshold of full blown AIDS. Beside these classic biological markers, numerous other parameters have been evaluated, without knowing their practical interest. Although the predictive markers for AIDS have a real statistical significance, their interpretation could be difficult or hazardous when applied to a sole individual. In a relatively short delay, the actual biological markers will probably be completed or changed, in the routine medical practice, by the use of direct virological markers evaluating the viral load (plasmatic or cellular viremia).
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PMID:[Estimated biological markers of progression in human immunodeficiency virus infection]. 129 68

Sixty-one subjects with mildly symptomatic human immunodeficiency virus (HIV) infection were included in a double-blind, randomized, placebo-controlled trial of zidovudine (part of AIDS Clinical Trials Group protocol 016, ACTG 016) to evaluate changes in the serum immune activation markers neopterin and beta 2-microglobulin (beta 2M) as early markers of the antiviral effect of zidovudine on HIV type 1 (HIV-1) infection. The mean values of serum neopterin and beta 2M levels in 27 placebo-treated subjects tended to increase with time. The mean value of neopterin in 34 subjects receiving zidovudine decreased at 4 weeks (15.76 nmol/L before treatment to 12.73 nmol/L, p = 0.001). The maximum reduction was seen at 8 weeks of treatment (10.78 nmol/L, p less than 0.0001). Subsequently, the mean value of serum neopterin increased but remained below the pretreatment value for more than a year. Serum beta 2M levels decreased (from 3.01 to 2.69 mg/L at 4 weeks, p = 0.01) and reached the lowest level at 8 weeks (2.45 mg/L, p = 0.0002) in zidovudine recipients. The mean beta 2M level returned to pretreatment value at approximately 24 weeks of the treatment. There was a close correlation between changes from baseline in serum neopterin and beta 2M during the first 16 weeks of the zidovudine therapy, but not later. Subjects with greater reductions of serum neopterin or beta 2M tended to maintain lower levels of these markers with continued zidovudine administration.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effect of zidovudine treatment on serum neopterin and beta 2-microglobulin levels in mildly symptomatic, HIV type 1 seropositive individuals. 134 7

We examined the association of three serum immune markers with CD4 cell counts in a large cohort of i.v. drug users with and without human immunodeficiency virus (HIV) infection. Levels of beta 2-microglobulin and neopterin were significantly elevated in HIV-infected subjects and increased in association with decline in CD4 cell counts (all p less than 0.001). Serum IgA levels in HIV-seropositive individuals were significantly elevated only when the CD4 cell count was less than 200/microliters (p less than 0.001). After controlling for HIV status and CD4 count, recent history of hepatitis was associated with significantly higher beta 2-microglobulin (p = 0.028) and marginally higher neopterin (p = 0.052) levels. There was no association of race, gender, or drug use patterns with levels of serum immune markers after controlling for HIV status and CD4 count. These data indicate that immune activation is coupled with immunosuppression in HIV-infected i.v. drug users. In addition, beta 2-microglobulin and neopterin levels are elevated in persons with a recent history of hepatitis but not in those with recent non-AIDS-defining bacterial infections. Markers of immune activation do not vary by race, gender, or drug use patterns among i.v. drug users.
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PMID:Immune serum markers and CD4 cell counts in HIV-infected intravenous drug users. 136 May 38

To investigate its use as a marker of disease severity, serum soluble CD4 (sCD4) was measured by ELISA in patients with human immunodeficiency virus (HIV) infection. Levels of sCD4 were higher in patients than in controls (P less than .001) but did not increase with disease severity. sCD4 release per CD4 lymphocyte showed a linear increase with disease severity and performed as well as beta 2-microglobulin, a widely used marker. To study the role of sCD4 in the pathogenesis of HIV infection, an ELISA to detect sCD4 complexed with glycoprotein 120 (gp120) HIV envelope protein was developed. Preformed sCD4-gp120 complexes were not detectable in patient serum, but addition of recombinant gp120 showed that circulating sCD4 is capable of binding HIV envelope proteins. This study indicates that the sCD4-to-CD4 lymphocyte ratio increases linearly with disease severity and may be a useful marker of CD4 lymphocyte damage. In addition, serum sCD4 can bind viral particles, which may have implications for the use of recombinant sCD4 as a therapy in HIV infection.
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PMID:Naturally occurring soluble CD4 in patients with human immunodeficiency virus infection. 134 32

Identification of laboratory tests that can help predict progression to acquired immunodeficiency syndrome (AIDS) in people infected with human immunodeficiency virus (HIV) is important for clinical management and counselling. We have assessed the usefulness of CD4 lymphocyte count, serum beta 2-microglobulin concentration, and the presence of p24 antigen as predictors of AIDS. We studied 214 homosexual and bisexual men with well-defined dates of HIV seroconversion. For each participant, we defined the baseline date as the earliest date before the development of AIDS on which the three laboratory tests were done. beta 2-microglobulin concentration at baseline was in all analyses an independent predictor of AIDS, even after stratification by baseline CD4 count, duration of HIV infection, or use of zidovudine before or at baseline. For example, among men with at least 0.5 x 10(9)/l CD4 cells who were negative for p24 antigen, the risks of AIDS at 12 months and 24 months were 1% and 5%, respectively, for those whose beta 2-microglobulin concentrations were below 4.0 mg/l, compared with 17% and 27%, respectively for those with beta 2-microglobulin concentrations above that cut-off point (p less than 0.001). Among men with an estimated duration of infection of 5 years or less, beta 2-microglobulin concentration was the strongest independent predictor of AIDS. Measurement of serum beta 2-microglobulin adds important prognostic information to CD4 count in determining the risk of progression to AIDS in HIV-infected subjects, including those whose CD4 cell count has not yet fallen.
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PMID:Serum beta 2-microglobulin and prediction of progression to AIDS in HIV infection. 137 63

One hundred forty-nine patients of private physicians in Toronto, Canada, who were positive for human immunodeficiency virus (HIV), medically stable, and had CD4 cell counts of < 700 cells/mm3 participated in a randomized, double-blind trial of placebo versus low-dose (50 U) versus high-dose (100 U) oral interferon-alpha. Treatment allocation was balanced according to baseline CD4 cell count and history of prior antiviral therapy. Patients were observed at 4 and 8 weeks for assessment of adverse events and several measures of disease status, including CD4 cell count, beta 2-microglobulin, weight, and Karnofsky score. We detected neither short-term benefits nor adverse effects from oral interferon-alpha therapy.
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PMID:Randomized, placebo-controlled, double-blind study of low-dose oral interferon-alpha in HIV-1 antibody positive patients. 135 52

Since prevalent cohorts may be biased by the duration of human immunodeficiency virus (HIV) infection (onset bias), it is useful to assess the potential predictive value of markers in incident cohorts of HIV-positive subjects for whom the date of seroconversion is known or can reliably be estimated. Of 131 homosexual men with HIV-1 seroconversion from New York City and Washington, DC, who were evaluated annually beginning in 1982, 60 developed acquired immunodeficiency syndrome (AIDS) by the end of 1989. The prognostic significance of immunologic markers (proportion of CD4+ T-lymphocytes, neopterin, beta 2-microglobulin, serum interferon, and anti-p24 antibody) and of a virologic marker (HIV p24 antigen) was determined using measurements made at defined time intervals after the known or estimated date of HIV seroconversion. When measurements made 3 years after seroconversion were used, all markers except anti-p24 antibody were found to be significant estimators of AIDS risk in univariate analyses. In multivariate Cox regression modeling, the maximum information was obtained by including neopterin, interferon, and the CD4+ T-lymphocyte proportion. The predictive value of markers after HIV seroconversion could change considerably from one interval to another. Elevated levels of beta 2-microglobulin and neopterin significantly predicted the development of Kaposi's sarcoma. These two markers were highly correlated (r = 0.74). The authors conclude that immunologic markers can be important for an HIV staging system for estimating prognosis and facilitating early therapeutic intervention in HIV-positive patients.
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PMID:Immunologic markers of progression to acquired immunodeficiency syndrome are time-dependent and illness-specific. 138 11

Quinolinic acid (QUIN) is an neurotoxic N-methyl-D-aspartate receptor agonist and an L-tryptophan metabolite of the kynurenine pathway. Increased concentrations of QUIN occur in both cerebrospinal fluid (CSF) and blood of patients infected with human immunodeficiency virus (HIV)-1, particularly those with neurologic disturbances. In the present study of HIV-1 infected patients in Walter Reed stages 4, 5 and 6, reductions in L-tryptophan accompanied proportional increases in L-kynurenine and QUIN in both serum and CSF. Further, close inter-correlations exist between QUIN kynurenic acid and L-kynurenine with both beta 2-microglobulin and neopterin in CSF and serum. These correlations support the hypotheses that the kynurenine pathway is activated in association with inflammation and induction of indoleamine-2,3-dioxygenase. There were no relationships between CSF QUIN, L-kynurenine or kynurenic acid with the ratio of serum:CSF albumin concentrations, which indicates that the increases in CSF QUIN, L-kynurenine or kynurenic acid were not dependent on a breakdown of the blood-brain barrier. Kynurenic acid is also a kynurenine pathway metabolite that can attenuate the excitotoxic effects of QUIN when present in higher molar concentrations. While CSF kynurenic acid levels were increased in HIV-1-infected patients, the magnitude of the increases were smaller than those of QUIN and the molar concentrations of kynurenic acid were consistently lower than QUIN by at least one order of magnitude. We conclude that immune activation increases the levels of neuroactive kynurenines within the central nervous system of HIV-1-infected patients secondary to activation of indoleamine-2,3-dioxygenase.
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PMID:Inter-relationships between quinolinic acid, neuroactive kynurenines, neopterin and beta 2-microglobulin in cerebrospinal fluid and serum of HIV-1-infected patients. 138 55

Peripheral blood mononuclear cells from 12 asymptomatic patients infected with immunodeficiency virus (HIV) and 4 patients with AIDS were analyzed before and during therapy with zidovudine for T helper cell (Th) function. Th function improved by more than fourfold to one or more of three stimuli tested in 9 (75%) of 12 asymptomatic patients on zidovudine therapy and in 3 of 4 patients with AIDS. Only 6 (7.4%) of 80 untreated HIV-infected control patients showed spontaneous improvement in Th function (P less than 10(-6)). Improved Th function was detected as early as 5 weeks into therapy in 6 patients and continued to be evident for greater than 1 year after start of therapy in 6 patients and for greater than 2 years in 2 patients. No correlation was observed between improved Th function and changes in CD4+ or CD8+ cell numbers or in levels of serum HIV p24 antigen or beta 2-microglobulin. These results suggest inclusion of in vitro Th function as a useful marker in determining the efficacy of antiretroviral drug therapy of HIV-infected patients.
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PMID:Reconstitution of long-term T helper cell function after zidovudine therapy in human immunodeficiency virus-infected patients. 138 95

Elevated cerebrospinal fluid (CSF) levels of neopterin and beta 2-microglobulin (beta 2MG) reflect activation of the cellular immune response in the central nervous system (CNS). In 118 consecutive subjects [15 controls and 103 patients with human immunodeficiency virus (HIV) infection classified according to the Walter Reed staging system (WR)], neopterin and beta 2MG were determined in paired samples of CSF and serum. The permeability of the blood-CSF barrier and local release of neopterin and beta 2MG were taken into account: The molecular weight and diameter were used to determine filtration at the blood-CSF barrier. CSF neopterin levels were increased in all stages of HIV infection. beta 2MG levels were elevated in WR2 and later stages. Neopterin, beta 2MG, and cell counts similarly showed peaks in WR2, as did neopterin and beta 2MG also in the later stages WR5 and WR6. Neurologically asymptomatic patients exhibited higher neopterin CSF levels than did controls (12.67 +/- 11.6 vs. 2.34 +/- 1.05 nmol/l, P less than 0.001) and higher CSF beta 2MG (2.12 +/- 1.25 vs. 1.3 +/- 0.37 mg/l, P = 0.001). Patients with HIV encephalopathy had higher levels of beta 2MG (3.75 +/- 1.83 mg/l) than asymptomatic patients (P less than 0.01). CSF levels of neopterin were markedly different in patients with HIV encephalopathy and toxoplasmosis (P less than 0.01). A high quantity of local release of the markers neopterin and beta 2MG may reflect HIV infection of the CNS in early and late stages and additional release upon opportunistic infections.
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PMID:Expansion of neopterin and beta 2-microglobulin in cerebrospinal fluid reaches maximum levels early and late in the course of human immunodeficiency virus infection. 139 42


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