The effects of highly active antiretroviral therapy on the serum levels of pro-inflammatory and anti-inflammatory cytokines in HIV infected subjects

Background

Cytokines play an important role in controlling the homeostasis of the immune system and infection with Human Immunodeficiency virus (HIV) leads to deregulated production of both pro- and anti-inflammatory cytokines. This study was designed to determine the effects of HIV and Highly Active Antiretroviral Therapy (HAART) on the levels of pro-and anti-inflammatory cytokines in HIV infected subjects.

Method

A total of 50 HIV infected and 50 HIV seronegative control participants were recruited for the study. The HIV infected subjects were recruited before commencement of antiretroviral therapy and were followed up for 12?months. Blood samples were collected at 3 different points: before initiation of therapy, 6?months into therapy and 12?months into therapy. Serum cytokines were analyzed using ELISA method while CD4+ T cells and viral load counts were measured using standard laboratory methods.

Result

The results showed that pro-inflammatory cytokines: Tumour necrosis factor-alpha (TNF-α), Interleukin-6 (IL-6) and anti-inflammatory cytokines Interleukin-4 (IL-4), Interleukin-10 (IL-10) and Transforming growth factor-beta (TGF-β) were significantly elevated in HIV infected subjects before commencement of therapy compared to 6?months and 12?months into therapy (P?<?0.01) and compared to control participants (P?<?0.01). TNF-α, TGF-beta remained significantly elevated even after 12?months of therapy compared to control participants (P?<?0.01), while IL-4, IL-6, and IL-10 showed no significant difference compared to control participants after 12?months of therapy (P?>?0.05). INF-γ was significantly reduced before commencement of therapy and after 12?months of therapy compared to control participants (P?<?0.05) respectively.

Conclusion

TNF-α and TGF-β remained significantly elevated even after 12?months of therapy, while IFN-γ remained significantly reduced after 12?months of therapy. Regulating these cytokines which were unresponsive to therapy could serve as a potential measure of therapy for HIV infected subjects. The positive effect of 12?months therapy on IL-4, IL-6 and IL-10 levels can be used to monitor disease prognosis during therapy especially in resource poor setting where regular viral load monitoring is unavailable.

     

Infection of Female Primary Lower Genital Tract Epithelial Cells after Natural Pseudotyping of HIV-1: Possible Implications for Sexual Transmission of HIV-1

The global AIDS pandemic continues to expand and in some regions of the world, such as southern Africa, the prevalence of HIV-1 infection exceeds 20%. The devastating spread of the virus in young women in these countries appears disproportional to overall risk of infection. Regions with high prevalence of HIV-1 are often also highly endemic for other pathogenic viruses including HSV, CMV and HTLV. We propose that acquisition by HIV-1 of the envelope glycoproteins of other viruses, in a process we call “natural pseudotyping,” expands the cellular tropism of HIV-1, enabling it to infect female genital epithelial cells directly and thereby dramatically increasing risk of infection during sexual intercourse. In this proof-of-concept study, we demonstrate that when HIV-1 co-infects T cells along with the gammaretrovirus xenotropic murine leukemia virus-related virus (XMRV), progeny HIV-1 particles are produced capable of infecting primary vaginal, ectocervical and endocervical epithelial cells. These cell types are normally resistant to HIV-1 infection. Infection of primary genital cells was neutralized by antisera against the XMRV glycoprotein, confirming that infection was mediated by the XMRV glycoprotein acquired through pseudotyping of HIV. Inhibition by AZT showed that active replication of HIV-1 occurred in these cells and ruled out non-specific endocytic uptake of the virus. These results demonstrate that natural pseudotyping can expand the tropism of HIV-1 to include genital epithelial cells and have potential implications for sexual transmission of the virus.     

Parameterizing the Logistic Model of Tumor Growth by DW-MRI and DCE-MRI Data to Predict Treatment Response and Changes in Breast Cancer Cellularity during Neoadjuvant Chemotherapy

Diffusion-weighted and dynamic contrast-enhanced magnetic resonance imaging (MRI) data of 28 patients were obtained pretreatment, after one cycle, and after completion of all cycles of neoadjuvant chemotherapy (NAC). For each patient at each time point, the tumor cell number was estimated using the apparent diffusion coefficient and the extravascular extracellular (v_e) and plasma volume (v_p) fractions. The proliferation/death rate was obtained using the number of tumor cells from the first two time points in conjunction with the logistic model of tumor growth, which was then used to predict tumor cellularity at the conclusion of NAC. The Pearson correlation coefficient between the predicted and the experimental number of tumor cells measured at the end of NAC was 0.81 (P = .0043). The proliferation rate estimated after the first cycle of therapy was able to separate patients who went on to achieve pathologic complete response from those who did not (P = .021) with a sensitivity and specificity of 82.4% and 72.7%, respectively. These data provide preliminary results indicating that incorporating readily available quantitative MRI data into a simple model of tumor growth can lead to potentially clinically relevant information for predicting an individual patient's response to NAC.     

Hepatic steatosis, inflammation, and ER stress in mice maintained long term on a very low-carbohydrate ketogenic diet

Nanotechnology is providing new and innovative means to detect, diagnose, and treat disease. In this regard, numerous nanoparticle-based approaches have been taken in an effort to develop an effective oral insulin therapy for the treatment of diabetes. This review summarizes efficacy data from studies that have evaluated oral insulin therapies in experimental models. Also provided here is an overview of the limited safety data that have been reported in these studies. To date, the most promising approaches for nanoparticle-based oral insulin therapy appear to involve the incorporation of insulin into complex multilayered nanoparticles that are mucoadhesive, biodegradable, biocompatible, and acid protected and into nanoparticles that are designed to take advantage of the vitamin B(12) uptake pathway. It is anticipated that the continued investigation and optimization of nanoparticle-based formulations for oral delivery of insulin will lead to a much sought-after noninvasive treatment for diabetes. Such investigations also may provide insight into the use of nanoparticle-based formulations for peptide- and protein-based oral treatment of other diseases and for various food-related purposes.     

Overexpression of cardiac connexin45 increases susceptibility to ventricular tachyarrhythmias in vivo

Electrophysiological remodeling involving gap junctions has been demonstrated in failing hearts and may contribute to intercellular uncoupling, delayed conduction, enhanced arrhythmias, and vulnerability to sudden death in patients with heart failure. Recently, we showed that failing human hearts exhibit marked increases in connexin45 (Cx45) expression in addition to previously documented decreases in connexin43 (Cx43) expression. Each of these changes results in reduced gap junction coupling. The objective of the present study was to examine functional consequences of increased Cx45 in cardiac gap junctions. Transgenic mice with cardiac-selective overexpression of the developmentally downregulated cardiac connexin, connexin45 (Cx45OE mice) were subjected to in vivo electrophysiology studies in which an intracardiac catheter was used to induce ventricular arrhythmias in anesthetized mice, and in which ambulatory ECG monitoring was used to detect spontaneous arrhythmias in unanesthetized mice. Hearts were analyzed by TaqMan RT-PCR, immunostaining, immunoblotting, and echocardiography. Lucifer yellow and neurobiotin dye transfer was used to assess coupling in transgenic and control myocyte cultures. Cx45 mRNA was two orders of magnitude greater in Cx45OE mice. Cx45-immunoreactive signal at gap junctions increased twofold and total Cx45 protein by immunoblotting increased 25% in Cx45OE mice compared with nontransgenic littermate controls. Functionally, Cx45OE mice exhibited more inducible ventricular tachycardia than controls but did not exhibit any other functional or structural derangements as assessed by echocardiography. Ventricular myocytes isolated from Cx45OE mice exhibited diminished intercellular transfer of Lucifer yellow dye and increased transfer of neurobiotin, consistent with altered cell-to-cell communication. Thus increased myocardial expression of Cx45 results in remodeling of intercellular coupling and greater susceptibility to ventricular arrhythmias in vivo.     

Identification and characterization of microsporidia from fecal samples of HIV-positive patients from Lagos, Nigeria

Background

Microsporidia are obligate intracellular parasites that infect a broad range of vertebrates and invertebrates. They have been increasingly recognized as human pathogens in AIDS patients, mainly associated with a life-threatening chronic diarrhea and systemic disease. However, to date the global epidemiology of human microsporidiosis is poorly understood, and recent data suggest that the incidence of these pathogens is much higher than previously reported and may represent a neglected etiological agent of more common diseases indeed in immunocompetent individuals. To contribute to the knowledge of microsporidia molecular epidemiology in HIV-positive patients in Nigeria, the authors tested stool samples proceeding from patients with and without diarrhea.

Methodology/Principal Findings

Stool samples from 193 HIV-positive patients with and without diarrhea (67 and 126 respectively) from Lagos (Nigeria) were investigated for the presence of microsporidia and Cryptosporidium using Weber’s Chromotrope-based stain, Kinyoun stain, IFAT and PCR. The Weber stain showed 45 fecal samples (23.3%) with characteristic microsporidia spores, and a significant association of microsporidia with diarrhea was observed (O.R.  = 18.2; CI: 95%). A similar result was obtained using Kinyoun stain, showing 44 (31,8%) positive samples with structures morphologically compatible with Cryptosporidium sp, 14 (31.8%) of them with infection mixed with microsporidia. The characterization of microsporidia species by IFAT and PCR allowed identification of Enterocytozoon bieneusi, Encephalitozoon intestinalis and E. cuniculi in 5, 2 and 1 samples respectively. The partial sequencing of the ITS region of the rRNA genes showed that the three isolates of E.bieneusi studied are included in Group I, one of which bears the genotype B.

Conclusions/Significance

To our knowledge, this is the first report of microsporidia characterization in fecal samples from HIV-positive patients from Lagos, Nigeria. These results focus attention on the need to include microsporidial diagnosis in the management of HIV/AIDS infection in Nigeria, at the very least when other more common pathogens have not been detected.