The ELISPOT assay is considered by many to be a gold standard for monitoring specific cellular immune responses. It can detect single cells secreting molecules of interest (1-3). This assay is highly sensitive, quantitative, easy to use and amenable to high throughput (4). Until recently assays using chromophores to detect the secretion of cytokines from single cells was limited by the difficul...

BACKGROUND Qualitative and quantitative changes in IGRA response offer promise as biomarkers to monitor Tuberculosis (TB) drug therapy, and for the comparison of new interventions. We studied the decay kinetics of TB-specific antigen T-cell responses measured with an in-house ELISPOT assay during the course of therapy. METHODS Newly diagnosed sputum smear positive TB cases with typical TB che...

Identification of individuals infected with Mycobacterium tuberculosis is essential for the control of tuberculosis (TB). The specificity of the currently used tuberculin skin test (TST) is poor because of the broad antigenic cross-reactivity of purified protein derivative (PPD) with BCG vaccine strains and environmental mycobacteria. Both ESAT-6 and CFP-10, two secretory proteins that are high...

Cytomegalovirus (CMV) primary infection or re-activation in solid organ transplant (SOT) recipients is associated with increased morbidity and mortality, with patients with IgG-CMV D+/R- sero-matching at greater risk. The impact of pre-transplant CMV-specific host cellular immunity on the long-term risk of CMV replication in kidney transplants (KT) was prospectively evaluated in eighty patients...

We recently set up a gamma interferon (IFN-gamma) enzyme-linked immunospot assay (ELISPOT), using selected early secreted antigenic target 6 (ESAT-6) peptides, that appears specific for active tuberculosis (A-TB). However, ELISPOT is difficult to automate. Thus, the objective of this study was to determine if the same selected peptides may be used in a technique more suitable for routine work i...

BACKGROUND We previously reported that an enzyme-linked immunospot (ELISPOT) assay for detecting anti-GPIIb/IIIa antibody-secreting B cells is a sensitive method for identifying patients with immune thrombocytopenia (ITP). Here we assessed the clinical significance of measuring circulating B cells producing antibodies to GPIb, another major platelet autoantigen. METHODS Anti-GPIb and anti-GPI...

Interferon (IFN)-gamma ELISPOT can be used to monitor the magnitude of virus-specific cellular immune responses in vaccine trials. Often, IFN-gamma ELISPOT is performed with cryopreserved peripheral blood mononuclear cells (PBMC). However, it has not been well defined yet to what extent diminished cell viability of PBMC following cryopreservation affects IFN-gamma responses in ELISPOT. Therefor...

BACKGROUND Accurate diagnosis of latent tuberculosis infection (LTBI) in recently exposed HIV-infected tuberculosis (TB) contacts is a public health priority because of the high risk of progression to active TB but is hampered by the high background prevalence of LTBI in high-burden populations and poor sensitivity of tuberculin skin testing (TST) in HIV co-infection. METHODS The prevalence o...

BACKGROUND Detection and treatment of latent TB infection (LTBI) in HIV infected individuals is strongly recommended to decrease morbidity and mortality in countries with high levels of HIV. OBJECTIVE To assess the validity of a newly developed in-house ELISPOT interferon-gamma release assay (IGRA) for the detection of LTBI amongst HIV infected individuals, in comparison with the Tuberculin S...

As soon as PBMC are isolated cells start dying. The rate of apoptotic cell death increases when PBMC are shipped, cryopreserved or stored under suboptimal conditions. Apoptotic cells secrete mediators such as Lactoferrin that suppress inflammation while promoting phagocytosis. The presence of apoptotic cells in PBMC may modulate functionality in antigen-specific T cell assays such as ELISPOT or...