Advanced HIV infection was associated with impaired MAC responses. Restoration of monocyte responses and expansion of polyfunctional MAC-specific T-betlow CD4+ T cells with cytotoxic potential after ART initiation may overwhelm existing regulatory and inhibitory mechanisms, leading to MAC-IRIS.

NCT02147405.

Canonical inflammasome activation is a tightly regulated process that has been implicated in a broad spectrum of inflammatory disorders. Inflammasome formation requires assembly of a cytosolic sensor protein with the adapter, ASC (apoptosis-associated speck-like protein containing a caspase activating and recruitment domain). Once formed, this multimeric protein structure allows for the activation of caspase-1, responsible for IL-1ß/IL-18 release. During this process, cytoplasmic dispersed ASC molecules cluster in one condensed micrometric-sized complex named ASC “speck,” which is traditionally assessed by fluorescence microscopy and widely accepted as a readout for canonical inflammasome activation. However, equally reliable but less time-consuming quantitative methods have emerged as a significant need in order to improve clinical assessment of inflammasome-related conditions. Multispectral imaging flow cytometry (MIFC) combines the qualitative power of fluorescence microscopy with high throughput capabilities and multiplexing potential of flow cytometry into one single system. Here we explored the optimal imaging-based tools to measure ASC speck formation via imaging flow cytometry by using peripheral blood mononuclear cells (PBMCs) stimulated with the NLRP3 agonist Nigericin, as a positive control. We demonstrate that this technique is also able to detect the distribution of active caspase-1 within the ASC aggregates by incubating cells with FAM-FLICA TM , a fluorochrome inhibitor of caspase-1. By applying these tools in PBMCs from patients with distinct inflammatory disorders we demonstrate that MIFC is able to assess canonical inflammasome activation in a quantitative and statistically robust manner in clinically relevant samples. Therefore, we propose that accurate assessment of specks by MIFC could help guide preventive or therapeutic strategies in an array of human inflammatory diseases in which inflammasomes play an important role.

METHODS.We hybridized 34 and 51 ICL patients' sera to a 9,000-human-proteome array and to a 128-known-autoantigen array, respectively. Using a flow-based method, we characterized the presence of anti-lymphocyte Abs in the whole cohort of 72 patients, as well as the Ab functional capability of inducing Ab-dependent cell-mediated cytotoxicity (ADCC), complement deposition, and complement-dependent cytotoxicity (CDC). We tested ex vivo the activation of the classical complement pathway on ICL CD4 + T cells. RESULTS.All ICL patients had a multitude of autoantibodies mostly directed against private (not shared) targets and unrelated quantitatively or qualitatively to the patients' autoimmune disease status. The targets included lymphocyte intracellular and membrane antigens, confirmed by the detection by flow of IgM and IgG (mostly IgG 1 and IgG 4 ) anti-CD4 + cell Abs in 50% of the patients, with half of these cases triggering lysis of CD4 + T cells. We also detected in vivo classical complement activation on CD4 + T cells in 14% of the whole cohort. CONCLUSION.Our data demonstrate that a high prevalence of autoantibodies in ICL, some of which are specific for CD4 + T cells, may contribute to pathogenesis, and may represent a potentially novel therapeutic target. TRIAL REGISTRATION. ClinicalTrials.gov NCT00867269.

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CD4 expression identifies a subset of mature T-cells primarily assisting the germinal center reaction and contributing to CD8 +-T-cell and B-cell activation, functions and longevity. Herein, we present a family in which a novel variant disrupting the translation-initiation-codon of the CD4 gene resulted in complete loss of membrane and plasma soluble-CD4 in peripheral blood, lymph node, bone marrow, skin and ileum of a homozygous proband. This inherited CD4-knock-out disease illustrates the clinical and immunological features of a complete deficiency of any functional component of CD4 and its similarities and differences with other clinical models of primary or acquired loss of CD4 +-T-cells.

A child is described who had the signs of autoimmune lymphoproliferative syndrome from an early age and later developed a blistering dermatosis that was shown to be childhood linear IgA disease.

In this review we will describe the immunopathogies of immune reconstitution inflammatory syndrome, IRIS. IRIS occurs in a small subset of HIV patient, initiating combination antiretroviral therapy (ART), where immune reconstitution becomes dyregulated, resulting in an overly robust antigen-specific inflammatory reaction. We will discuss IRIS in terms of the associated coinfections: mycobacteria, cryptococci, and viruses.