Prognostic value of single measurements of beta-2-microglobulin, immunoglobulin A in HIV disease after controlling for CD4 lymphocyte counts and plasma HIV RNA levels

High levels of serum β2-microglobulin predict severity of coronary artery disease

BACKGROUND

The identification of new risk factors for coronary artery disease (CAD) is increasingly sought in an effort to tackle this threatening disease. β2-microglobulin (B2M) is reported to associate with peripheral arterial disease and adverse cardiovascular outcomes. However, the association between B2M and cardiovascular disease remains under-researched. This study evaluated the effects of B2M on CAD without renal dysfunction.

METHODS

One thousand seven hundred sixty-two subjects (403 non-CAD subjects and 1,359 CAD subjects) were investigated. Fasting samples were collected to determine B2M level. The Gensini and SYNTAX scores were used to assess the severity of CAD.

RESULTS

CAD subjects were significantly higher in serum B2M level comparing with non-CAD subjects (1.25 ± 0.46 vs 1.14 ± 0.28 mg/L, p < 0.001). Serum B2M level was a risk factor of CAD after adjusting potential confounders (Odds Ratio (OR) = 2.363, 95% confidence interval (CI): 1.467-3.906, p = 0.001). Receiver operating characteristics (ROC) showed B2M level moderately predicted diagnosis of CAD (the area under the ROC curve (AUC) = 0.608, 95% CI: 0.577-0.639, p < 0.001). Furthermore, serum B2M level was positively associated with Gensini score system, SYNTAX score system and the number of disease vessels (NDV ≥ 2).

CONCLUSIONS

The significant association between serum B2M and CAD suggests that B2M could be a biomarker for CAD.

Value of β2-microglobulin in the serum of healthy subjects older than 40 years

The aim of this research was to determine if the age of healthy subjects older than 40 years of age has an influence on the concentration of β(2) -microglobulin in the serum of subjects of different populations. We examined the values of β(2) -microglobulin in the serum of 51 healthy subjects aged 40-86 years using the microparticle enzyme immunoassay AxSYM β(2) -microglobulin test. The reference values of β(2) -microglobulin according to the nonparametric statistical method is 0.95-2.73 mg/L. A correlation was found between β(2) -microglobulin and age: 40-50 years (0.94-1.54 mg/L), 51-65 years (0.96-2.62 mg/L), and >65 years (1.13-2.84 mg/L). There was no significant statistical difference of β(2) -microglobulin between genders (P > 0.05); however, there was a statistically significant difference between the concentration of β(2) -microglobulin and the subjects' age. (Spearman's rank correlation coefficient ρ = 0.66; P < 0.01). A direct correlation between age and the concentration of β(2) -microglobulin was observed. This research is a contribution to determining reference values of β(2) -microglobulin in subjects of different populations.

Residual viraemia in HIV-1-infected patients with plasma viral load <or=20 copies/ml is associated with increased blood levels of soluble immune activation markers

Despite undetectable viral load in conventional assays, probably all human immunodeficiency virus (HIV)-1 infected patients have residual viraemia (RV) detectable by ultra-sensitive assays. To study this issue, this study investigated virologic and immunologic consequences of RV in highly active antiretroviral therapy (HAART)-treated HIV-1-infected patients with plasma HIV-1 RNA <or=20 copies/ml. The study included 32 HAART-treated HIV-1-infected patients with HIV-1 RNA <or=20 copies/ml followed prospectively 6-monthly for 24 months. RV was detected by transcription-mediated amplification (TMA-RV) technique (Procleix HIV-1 Discriminatory Assay; Chiron) and by PCR (PCR-RV, Amplicor HIV-1 Monitor Assay; Roche Diagnostics). The association between RV and proviral-HIV-1-DNA, CD4-count, CD8-count, soluble [soluble tumour necrosis factor receptor (TNFr)-II, beta(2)-microglobulin, immunoglobulins] and cellular (HLA-DR, CD38, CD45RO, CD45RA, CD62L) T-cell markers of immune activation was investigated. In the 24-months study-period, 23 patients had >or=1 episode with TMA-RV whereas 9 patients had undetectable TMA-RV throughout the study-period. Time-points with TMA-RV and PCR-RV were associated with higher circulating sTNFrII (+0.234 ng/ml, P = 0.030) and beta(2)-microglobulin (+22 nmol/l, P = 0.016) and time-points with PCR-RV were also associated with higher IgA (+0.82 micromol/l, P = 0.035) and CD8-count (+1.18-fold, P = 0.001). Patients with TMA-RV in the study-period had higher HIV-1 RNA pre-HAART (P = 0.032). RV was not associated with proviral-HIV-1-DNA, CD4-count, CD4+HLA-DR+, CD8+HLA-DR+CD38+, CD4+CD45RA-CD45RO+, CD8+CD45RA-CD45RO+, CD4+CD45RA+CD62L+, CD8+CD45RA+CD62L+ T cells, IgG or IgM. In conclusion, RV was associated with increased blood levels of soluble immune activation markers in HAART-treated HIV-1-infected patients. The finding that RV was associated with higher pre-HAART plasma viral load suggests that RV is linked to pre-HAART disease progression.

Plasma levels of soluble urokinase-type plasminogen activator receptor (suPAR) and early mortality risk among patients enrolling for antiretroviral treatment in South Africa

Background

Serum concentrations of soluble urokinase-type plasminogen activator receptor (suPAR) have a strong independent association with HIV-1-related mortality. The practical utility of plasma suPAR in assessing short-term all-cause mortality risk was evaluated in patients with advanced immunodeficiency enrolling in an antiretroviral treatment (ART) programme in South Africa.

Methods

An enzyme-linked immunosorbent assay (ELISA) was used to measure plasma concentrations of suPAR in patients at the time of enrolment to the ART programme. The association between plasma suPAR concentrations, baseline patient characteristics and cohort outcomes after 4 months of ART were determined.

Results

Patients (n = 293, 70% female) had a median age of 33 years and were followed up for a median of 5 months from enrolment. The median CD4 cell count was 47 cells/μl (IQR = 22–72) and 38% of patients had WHO stage 4 disease. 218 (74%) patients remained alive after 4 months of ART; 39 (13%) died and 36 (12%) were lost to the programme for other reasons. Patients who died had significantly higher plasma suPAR concentrations compared to those who either survived (P < 0.01) or left the programme for other reasons (P < 0.043). In multivariate analysis, higher log₁₀ suPAR concentrations were significantly associated with lower CD4 cell counts, WHO clinical stage 4 disease and male sex. In multivariate analysis to identify factors associated with death, log₁₀ suPAR concentration was the most strongly associated variable (P < 0.001). However, examination of sensitivity and specificity characteristics using receiver operating characteristic (ROC) analysis revealed that results from this assay did not have a discriminatory cut-point to provide clinically useful information.

Conclusion

Plasma suPAR concentration was the strongest independent predictor of short-term mortality risk among patients with advanced immunodeficiency enrolling in this ART programme. However, lack of a discriminatory threshold did not permit this marker to be used to triage patients according to short-term mortality risk.

Persistent anti-gag, -Nef, and -Rev IgM levels as markers of the impaired functions of CD4+ T-helper lymphocytes during SIVmac251 infection of cynomolgus macaques

This study analyzed the antigen-specific (Gag, Nef, Rev, and Tat) IgM, IgG, and IgA humoral responses during the first 200 days of SIVmac251 infection in cynomolgus macaques. These responses were tested for correlation with the CD4(+) T-cell-related hematologic parameters and viral load throughout the course of the study (acute and chronic infection, during and after antiretroviral therapy). Strong inverse correlations were observed between the percentage of CD4(+) T cells at almost every timepoint of the study and the levels of IgM (but not IgG and IgA) against Gag, Nef, and Rev (but not Tat) measured after, but not during, the primary peak of IgM response. Significant levels of persistent antigen-specific IgMs may reflect the prevalence of mature plasma cells that have not undergone immunoglobulin class switching, possibly due to defects in helper T-cell function. Strong correlations were observed between the preinfection CD4(+) T-cell count or CD4/CD8 ratio and the same parameters measured throughout the study, suggesting the importance of preinfection immune status as a determinant of disease progression. The negative correlations between the post-acute-phase IgM levels and the percentage of CD4(+) T cells at later times during the study suggest the potential prognostic value of this measurement.

Immunological predictors of survival in HIV type 2-infected rural villagers in Guinea-Bissau

We investigated the association between beta2-microglobulin, neopterin, serum levels of soluble urokinase-type plasminogen activator receptor (suPAR), CD4 count, and plasma viremia with survival in 133 HIV-2-infected villagers and 160 controls living in rural Guinea-Bissau. Subjects were recruited in 1991 and visited at home every 3-6 months until 1998. Median beta2-microglobulin, neopterin, and suPAR were significantly higher and CD4% significantly lower among HIV-2-infected individuals than controls. Thirty-one HIV-2-infected individuals died and 7 were lost to follow-up. beta2-Microglobulin, CD4%, and plasma viral load were associated independently with survival in multivariate analyses. Neopterin and suPAR did not reach statistical significance. These findings suggest that immune activation is central to the pathogenesis of HIV. They also have important implications for resource-poor settings where CD4 count and plasma viral load are unaffordable.

Relationship of .BETA.2-Microglobulin to Arterial Stiffness in Japanese Subjects

Beta2-Microglobulin (beta2m) is related to inflammatory diseases, but there have been few reports of a relationship between beta2m and atherosclerosis. We have examined the influence of beta2m on brachial-ankle pulse wave velocity (baPWV) to clarify whether it is related to arterial stiffness. baPWV, beta2m, C-reactive protein (CRP), and conventional risk factors were measured in 614 males and 158 females. The adjusted means of baPWV were compared with the quartiles of beta2m, and significant differences in baPWV were observed across the quartiles of beta2m (p = 0.037). After being adjusted for potential confounders, quartile 4 of beta2m, quartile 4 of CRP, and the combination of high beta2m plus high CRP were significantly associated with a high value of PWV (quartile 4 of beta2m: odds ratio [OR] 2.53, 95% confidence interval [CI], 1.31-4.89; quartile 4 of CRP: OR 2.27, 95% CI, 1.18-4.34; high beta2m plus high CRP: OR 5.60, 95% CI, 2.38-13.2). These results suggest that beta2m is associated with an increase of arterial stiffness. Further studies are needed to clarify whether beta2m is related to atherosclerotic diseases, and whether the combination of beta2m and CRP measurement is a useful predictor for the development of atherosclerosis.

HIV-infected children with moderate/severe immune-suppression: changes in the immune system after highly active antiretroviral therapy

The objective of this study was to monitor the changes in the immune system of HIV-infected children with moderate or severe immunodeficiency after highly active antiretroviral therapy (HAART), comprising a follow-up study in 14 HIV-infected children on HAART at two time points separated approximately by 11.8 +/- 0.4 (9.9; 15.4) months. HIV-infected children had significantly lower TREC levels than the control group, but 1 year after HAART the levels increased significantly (P < 0.05). In contrast, viral load (VL) did not change significantly. A positive correlation between T cell receptor excision circle (TREC) levels and both CD4(+) T cell absolute counts (r = 0.558; P = 0.05) and percentages (r = 0.625; P = 0.030) was found. During follow-up on HAART, the percentages and absolute counts of naive CD4(+) and CD8(+) T cell subsets were increased significantly (P < 0.05). CD4(+) CD45RA(hi+) CD62L(+), CD4(+) CD45RA(+) and CD4(+) CD38(+) percentages, and the CD8(+) CD45RA(hi+) CD62L(+) counts reached similar values to the control group. Also, CD8(+) CD45RO(+) CD38(+) and CD8(+) CD45RO(+) percentages, and CD8(+) CD45RO(+) CD38(+) absolute counts (P < 0.05) decreased with respect to the baseline. Lymphoproliferative responses to pokeweed mitogen (PWM) before HAART were lower in HIV-infected children than the control group, but they recovered to normal levels after a year on HAART. Tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma production by PHA-activated peripheral blood mononuclear cells (PBMC) was lower before HAART (P < 0.001), but reached similar levels to the control group 1 year after HAART. In HIV-infected children IgG, IgG(1) and IgG(3) plasma levels decreased significantly after HAART. The immune system reconstitution induced by HAART in HIV-infected children seems to be the consequence of decreased immune system activation and naive T cell reconstitution, mainly of thymic origin.

Immunoglobulin levels amongst persons with and without human immunodeficiency virus type 1 infection in Uganda and Norway

CD4+-cell count and viral load monitoring are expensive and unavailable to most human immunodeficiency virus (HIV)-infected people in Africa. In an attempt to evaluate alternative methods for monitoring antiretroviral (ARV) therapy, we measured concentrations of immunoglobulin (Ig)A, IgM, IgG and IgG1 amongst adults with and without HIV in Uganda and Norway. We adjusted for disease severity by stratifying HIV-positive subjects on CD4+-cell counts above and below 200 cells/ micro l. Median serum levels of IgG, IgG1 and IgA were significantly higher in HIV-positive persons compared with HIV-negative persons in both countries (P < 0.001 and P = 0.018 for IgA in Ugandan patients). Levels of IgA in Ugandan HIV-negative subjects were significantly lower than those in HIV-positive subjects with low CD4+ compared with those with high CD4+-cell counts (P < 0.001 and P = 0.069, respectively). IgM levels were different between the HIV-negative and the two HIV-positive groups in Norway (P < 0.001). The mean levels of IgM, IgG and IgG1 in HIV-negative and -positive African subjects were generally higher than those in comparable groups of Western subjects. Our results verify that levels of IgA, IgG and IgG1 vary between HIV-negative and -positive individuals in both study populations. Their determination may be useful in monitoring both disease progression and response to ARV therapy.

Cervico-mediastinal lymphadenopathy as a paradoxical response to chemotherapy in pulmonary tuberculosis. A case report

We report a case of pulmonary tuberculosis who developed tuberculous mediastinal and later cervical lymphadenopathy while on antituberculous chemotherapy. She responded to the addition of oral corticosteroids to her regimen. The relevant literature regarding the pathogenesis, varied manifestations and the clinical importance of recognising a paradoxical response is discussed.

Serum level of soluble urokinase-type plasminogen activator receptor is a strong and independent predictor of survival in human immunodeficiency virus infection

Human immunodeficiency virus-1 (HIV-1) infection has been shown to result in up-regulation of the urokinase-type plasminogen activator receptor (uPAR/CD87) on leukocytes in vitro and in vivo. The objective of this study was to investigate whether this up-regulation is paralleled by higher serum levels of soluble uPAR (suPAR) in patients with advanced HIV-1 disease and whether the serum level of suPAR is predictive of clinical outcome. Using an enzyme-linked immunosorbent assay, the level of suPAR was measured retrospectively in serum samples from 314 patients with HIV-1 infection. By Kaplan-Meier and Cox regression analyses, the serum suPAR levels were correlated to survival with AIDS-related death as the end point. High levels of serum suPAR (greater than median) were associated with poor overall survival, and Kaplan-Meier analysis on patients stratified by suPAR level demonstrated a continuous increase in mortality rates with higher suPAR levels. After adjustment for accepted prognostic markers—including Centers for Disease Control and Prevention–defined clinical stages, CD4 counts, viral load, β2-microglobulin, and age—the prognostic strength of suPAR remained highly significant, indicating that the serum suPAR level is a novel, strong, and independent predictor of survival in HIV-1 infection. This report is the first to demonstrate an important association between the plasminogen activator system and disease progression in HIV-1 infection.