Negar Shafiei Sabet

HIV-Mycobacterium tuberculosis co-infection: a 'danger-couple model' of disease pathogenesis

Tuberculosis (TB) and human immunodeficiency virus (HIV) infection interfere and impact the pathogenesis phenomena of each other. Owing to atypical clinical presentations and diagnostic complications, HIV/TB co-infection continues to be a menace for healthcare providers. Although the increased access to highly active antiretroviral therapy (HAART) has led to a reduction in HIV-associated opportunistic infections and mortality, the concurrent management of HIV/TB co-infection remains a challenge owing to adverse effects, complex drug interactions, overlapping toxicities and tuberculosis -associated immune reconstitution inflammatory syndrome. Several hypotheses have been put forward for the exacerbation of tuberculosis by HIV and vice versa supported by immunological studies. Discussion on the mechanisms produced by infectious cofactors with impact on disease pathology could shed light on how to design potential interventions that could decelerate disease progression. With no vaccine for HIV and lack of an effective vaccine for tuberculosis, it is essential to design strategies against HIV-TB co-infection.

Recent advances targeting innate immunity-mediated therapies against HIV-1 infection.

Early defence mechanisms of innate immunity respond rapidly to infection against HIV‐1 in the genital mucosa. Additionally, innate immunity optimises effective adaptive immune responses against persistent HIV infection. Recent research has highlighted the intrinsic roles of apolipoprotein B mRNA‐editing, enzyme‐catalytic, polypeptide‐like 3G, tripartite motif‐containing protein 5, tetherin, sterile α‐motif and histidine/aspartic acid domain‐containing protein 1 in restricting HIV‐1 replication. Likewise, certain endogenously secreted antimicrobial peptides, namely α/β/θ‐defensins, lactoferrins, secretory leukocyte protease inhibitor, trappin‐2/elafin and macrophage inflammatory protein‐3α are reportedly protective. Whilst certain factors directly inhibit HIV, others can be permissive. Interferon‐λ3 exerts an anti‐HIV function by activating Janus kinase‐signal transducer and activator of transcription‐mediated innate responses. Morphine has been found to impair intracellular innate immunity, contributing to HIV establishment in macrophages. Interestingly, protegrin‐1 could be used therapeutically to inhibit early HIV‐1 establishment. Moreover, chloroquine inhibits plasmacytoid dendritic cell activation and improves effective T‐cell responses. This minireview summarizes the recently identified targets for innate immunity‐mediated therapies and outlines the challenges that lie ahead in improving treatment of HIV infection.

Concurrent loss of co-stimulatory molecules and functional cytokine secretion attributes leads to proliferative senescence of CD8+ T cells in HIV/TB co-infection

The role of T-cell immunosenescence and functional CD8(+) T-cell responses in HIV/TB co-infection is unclear. We examined and correlated surrogate markers of HIV disease progression with immune activation, immunosenescence and differentiation using T-cell pools of HIV/TB co-infected, HIV-infected and healthy controls. Our investigations showed increased plasma viremia and reduced CD4/CD8 T-cell ratio in HIV/TB co-infected subjects relative to HIV-infected, and also a closer association with changes in the expression of CD38, a cyclic ADP ribose hydrolase and CD57, which were consistently expressed on late-senescent CD8(+) T cells. Up-regulation of CD57 and CD38 were directly proportional to lack of co-stimulatory markers on CD8(+) T cells, besides diminished expression of CD127 (IL-7Rα) on CD57(+)CD4(+) T cells. Notably, intracellular IFN-γ, perforin and granzyme B levels in HIV-specific CD8(+) T cells of HIV/TB co-infected subjects were diminished. Intracellular CD57 levels in HIV gag p24-specific CD8(+) T cells were significantly increased in HIV/TB co-infection. We suggest that HIV-TB co-infection contributes to senescence associated with chronic immune activation, which could be due to functional insufficiency of CD8(+) T cells.

Temporal proteomic profiling of Chlamydia trachomatis–infected HeLa‐229 human cervical epithelial cells

Chlamydia trachomatis is the leading causative agent of bacterial sexually transmitted infections worldwide which can lead to female pelvic inflammatory disease and infertility. A greater understanding of host response during chlamydial infection is essential to design intervention technique to reduce the increasing incidence rate of genital chlamydial infection. In this study, we investigated proteome changes in epithelial cells during C. trachomatis infection by using an isobaric tags for relative and absolute quantitation (iTRAQ) labeling technique coupled with a liquid chromatography‐tandem mass spectrometry (LC‐MS3) analysis. C. trachomatis (serovar D, MOI 1)–infected HeLa‐229 human cervical carcinoma epithelial cells (at 2, 4 and 8 h) showed profound modifications of proteome profile which involved 606 host proteins. MGST1, SUGP2 and ATXN10 were among the top in the list of the differentially upregulated protein. Through pathway analysis, we suggested the involvement of eukaryotic initiation factor 2 (eIF2) and mammalian target of rapamycin (mTOR) in host cells upon C. trachomatis infection. Network analysis underscored the participation of DNA repair mechanism during C. trachomatis infection. In summary, intense modifications of proteome profile in C. trachomatis–infected HeLa‐229 cells indicate complex host‐pathogen interactions at early phase of chlamydial infection.

Differential Expression of Serum Ceruloplasmin and Alpha2-HS Glycoprotein among Nasopharyngeal Carcinoma Patients

The two-dimensional gel electrophoresis (2-DE) approach was used to evaluate the simultaneous expression of serum proteins in patients with nasopharyngeal carcinoma (NPC) and to detect differentially expressed proteins which could be used as specific and sensitive biomarkers for early diagnosis of the disease. We have subjected unfractionated whole sera of ten newly diagnosed Malaysian Chinese patients with World Health Organization (WHO) type III NPC to 2-DE and image analysis. The results obtained were then compared to that generated from sera of ten normal healthy controls of the same ethnic group and range of age. Our data showed higher expression of ceruloplasmin (CPL) and lower expression of α2-HS glycoprotein (AHS) in the serum high abundance 2-DE protein profiles of NPC patients as compared to that of the normal healthy controls. The ceruloplasmin (CPL) and α2-HS glycoprotein (AHS) spots were identified by mass spectrometric analysis and Mascot database search. In conclusions, this information may help in early diagnosis of nasopharyngeal carcinoma.

Protein Map Standardization of Human Saliva Using Two Dimensional Gel Electrophoresis (2-DE)

Over the past decade, the use of saliva as an auxiliary diagnostic tool for biomarker detection has gained considerable acceptance as a non-invasive, inexpensive alternative to conventional serum method. In proteomics, the most promising technique which can be used for detecting salivary biomarker with sufficient resolving power is two-dimensional gel electrophoresis (2-DE) that provides a unique platform for the simultaneous separation of proteins in a complex mixture. However, as a fact most of the new scientists in developing countries are still facing problems with optimization of 2-DE techniques because the performance of optimization techniques in proteomics research using 2-DE has its own limitations. Therefore, the present study was established to generate a reproducible and optimized protocol to display the 2-DE protein map of human saliva. Our results showed the standard optimization of the 2-DE protein mapping was achieved at pH 3-10 with 60 μg proteins loading. This protocol could be used by other scientists along with identification of differentially expressed proteins by mass spectrometry when 2-DE protein map of patients saliva are compared to that of normal healthy individuals. These differentially expressed proteins could be later used as specific and sensitive biomarkers for early diagnosis and prognosis of the disease in question. In conclusion, the procedure used in our study generated a highly reproducible and optimized reference 2-DE protein mapping of human saliva.