Antibody and cytokine serum levels in patients subjected to anti-rabies prophylaxis with serum-vaccination

Rabies is considered a fatal disease once clinical symptoms have developed. The aim of this study was to evaluate epidemiological aspects and immune response in patients attacked by domestic and wild animals and subjected to post-exposure rabies treatment with equine serum and associated vaccine. Thirty-three patients were evaluated; they were between 13 and 65 years old, 75.8% were male and 24.2% female, and from the Botucatu neighborhood. Twenty healthy control individuals with the same age range were also studied. Specific antibodies to equine immunoglobulins and IFN-gamma, IL-2, IL-4, and IL-10 production were evaluated by ELISA. IgM, IgE, IgG and subclasses, and rabies virus antibodies serum levels were determined by nephelometry and seroneutralization methods, respectively. No anaphylactic or serum sickness allergic reactions were observed in patients after treatment. Anti-equine IgG levels were significantly higher than those of IgM after 14 and 28 days of treatment. Protective antibodies to rabies virus > 0.5 UI/ml were detected in 84.6% and 75% of patients at days 14 and 28, respectively. IFN-gamma, IL-2 and IL-10 levels in patients before and 48h after treatment were significantly higher than in controls suggesting that both Th1 and Th2 cells were activated in the patients. Serum IgM levels were higher at day 14, and IgG2 and IgE levels were higher at day 28 of treatment. These results suggest that post-exposure rabies treatment in humans induces significant alterations in patient immune response characterized by increased levels of cytokines, serum levels of specific rabies virus antibodies, and the equine serum components employed in the treatment.

Immune reconstitution in HIV-1 infected patients treated for two years with highly active antiretroviral therapy

The aim of this paper was to evaluate the immune reconstitution of HIV-1 patients subjected to highly active antiretroviral therapy (HAART) for two years or more according to CD45RA and CD45RO cell count; determination of IL-2, IFN-gamma, IL-4, IL-10 and TNF-alpha serum levels; CD4+ T and CD8+ T lymphocyte count; and plasma viral load (VL) determination. For this purpose, a cross sectional study was carried out in the Tropical Diseases Area, Botucatu School of Medicine, São Paulo State University, UNESP, Botucatu, São Paulo, Brazil. Between June 2001 and April 2002, 37 HIV-1 infected patients were evaluated, 13 with treatment indication but untreated (G1), 9 subjected to HAART for 5-7 months (G2), and 15 treated for two years or more (G3); both treated groups used medication regularly and without failure. Forty-nine normal individuals were studied as controls (GC-1 and GC-2). There was a tendency (p 0.10) for the predominance of two nucleoside reverse transcriptase inhibitors (NRTI) associated with one non-nucleoside reverse transcriptase inhibitor (NNRTI) regimen in G2; and two NRTI associated with a protease inhibitor (PI) in G3. Statistical differences between groups were seen for CD45RA (G1 [G3=GC-2]; p 0.05) and CD45RO (G1 GC-2 G3; p 0.01) cells, and CD4+ T lymphocyte count (G1 G3; G2-intermediate; p 0.05), VL determination (G1>[G2=G3]; p 0.001), TNF-alpha serum determination ([G1>G3; G2=intermediate]>GC-1; p 0.001), IL-2 (G1 [G2=G3=GC-1]; p 0.01), IFN-gamma ([G1=GC-1] [GC-2=G3]; p 0.001), IL-4 and IL-10 ([G1=G2=G3]>GC-1; p 0.001), serum cytokine profiles, with a higher proportion of subtype 2 in G1 and mature subtype 0 in G2 and G3 (p 0.005). There was no statistical difference for CD8+ T lymphocyte counts (G1=G2=G3; p 0.50). Consistency was seen between positive correlations of profile 1 definer cytokines (IL-2 and IFN-gamma), CD45RA and CD45RO cells, and CD4+ T lymphocyte counts and between positive correlations of profile 2 definer cytokines (IL-4 and IL-10) with TNF-alpha, and VL. The negative correlations were also consistent as they expressed the inverse of the positives. The variables with the highest number of correlations were IL-2, IFN-gamma, and VL, followed by CD45RA and CD45RO cells, and IL-10. The variables with the lowest number of correlations were CD4+ T and CD8+ T lymphocytes. The results express the partial but important immune reconstitution in HIV-1 infected individuals with the interference of HAART and the importance of cytokines especially IL-2 and IFN-gamma, and CD45RA and CD45RO cells as surrogate markers of this reconstitution.

Measurement of IL-10 serum levels in BALB/c mice treated with beta-1,3 polyglucose or sulfadiazine and acutely infected by Toxoplasma gondii

Acute infection by Toxoplasma gondii leads to suppression of cell-mediated immunity, facilitating chronic infection. One of the causes of immunosuppression is Interleukin-10 (IL-10) production. Glucan is used to stimulate phagocytosis. Our objective was to study IL-10 induction in male BALB/c mice with acute T. gondii BTU-2 strain infection, glucan immunostimulation, and sulfadiazine treatment. Animals were distributed into 7 groups: G1: infected with T. gondii; G2: infected with T. gondii and treated with sulfadiazine; G3: infected with T. gondii and immunostimulated with glucan; G4: infected with T. gondii, immunostimulated with glucan, and treated with sulfadiazine; G5: imunostimulated with glucan; G6: treated with saline; and G7: treated with sulfadiazine. IL-10 levels were determined by ELISA; the highest levels were found in G2, G3 and G4, and the lowest in G1 (p 0.001). Groups G1 to G5 and G7 had substantially higher levels than G6 (p 0.001). In this study, the highest IL-10 levels were found in groups treated with glucan.

Correlation between cytokine serum levels, number of CD4+ T cells/mm³ and viral load in HIV-1 infected individuals with or without antiretroviral therapy

Seventy-nine HIV-1 infected patients were studied in three groups: Group G1 - 11 patients with no antiretroviral therapy; G2 - 40 patients undergoing antiretroviral therapy, 33 with only two nucleoside reverse transcriptase inhibitors (NRTI), and seven with two NRTI and one protease inhibitor (PI), all with viral load (VL) equal or higher than 80 copies of plasma RNA/ml; Group G3 - 28 patients, 23 on highly active antiretroviral therapy (HAART), 18 with two NRTI and one PI, and five with two NRTI and one non-nucleoside reverse transcriptase inhibitor (NNRTI), the remaining five with combination of two NRTI. All G3 patients had undetectable viral load for at least the past six months. The control group (Gc) included 20 normal blood donors without clinical complaints or signs of disease and negative for anti-HIV-1/2 antibodies. Serum cytokine levels pg/ml (TNF-alpha, INF-gamma, IL-2, IL-4, and IL-10) were determined in all patients including controls. CD4+ T and CD8+ T lymphocyte counts were made in the 79 patients by flow cytometry; VL determination was by NASBA technology. Analysis of results showed that the number of CD4+ T and CD8+ T lymphocytes were higher in G2 than G1, while VL was 0.5 log lower. G3 patients had similar lymphocyte values to G2, however they were chosen for G3 because their VL was undetectable, different by 4.0 log to G2. These results show the effect of antiretroviral treatment in G2 and G3 patients with better performance in the latter. Statistical difference was seen between the three groups and controls for serum cytokine behavior: TNF-alpha [H=48.323; p 0.001;(G1=G2=G3)>Gc]; INF-gamma[H=28.992; p 0.001; (G1=G2=G3)>Gc]; IL-4[H=48.323; p 0.001; (G1=G2=G3)>Gc]; IL-10[H=47.256; p 0.001; (G1=G2=G3)>Gc. There was no statistical difference in IL-2 values between all groups (H=6.071; p>0.10; G1=G2=G3=Gc). In absolute values however, G3 showed slightly lower TNF-alpha, IL-4, and IL-10, and higher INF-gamma and IL-2, to G1 and G2. This suggests a better performance in G3 patients, especially in IL-2 behavior. For cytokine profile, the three groups showed mature Th0 subset. In G1 72.73% were mature Th0, and 27.27% Th2; G2, 72.50% mature Th0, and 27.50% Th2; and G3, 89.29% mature Th0, and 10.71% Th2. There was no statistical difference between groups (chi22=3.014; p>0.10; G1=G2=G3). Statistical difference was seen between G2 and G3 for antiretroviral regimes used (chi21=27.932; p 0.001; G3>G2); HAART with PI predominated in G3, suggesting that it was responsible for this better performance. Linear correlation between pairs of variables was made with patient groups only, excluding controls. This was made separately for G1 and G2, 51 patients with detectable VL, and G1, G2, and G3 also including those with undetectable VL. The results showed a strong positive correlation between TNF-alpha and IL-4; TNF-alpha and IL-10; INF-gamma and IL-2; IL-4 and IL-10; IL-2 and CD4+. Weak negative correlation was seen between IL-2 and VL. Considering all correlations together, we found that IL-2 had the most correlations - eleven - strong, weak, positive, and negative; it was the only one that correlated with CD4+ (positively) and LV (negatively). The number of correlations allowed us to evaluate qualitative aspects such as IL-2 correlated positively with INF-gamma and CD4+ and negatively with LV; this somehow expresses the compatible profile with subset Th1, which could signify a tendency towards immune response recovery. Determination of cytokine serum values, especially IL-2, could be useful in follow-up of HIV-1 infected patients under HAART together with CD4+ and VL count.