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Objective: To determine whether latency can be established and reversed in both proliferating and nonproliferating CD4+ T cells in the same model in vitro., Methods: Activated CD4+ T cells were infected with either a nonreplication competent, luciferase reporter virus or wild-type full-length enhanced green fluorescent protein (EGFP) reporter virus and cultured for 12 days. The cells were then sorted by flow cytometry to obtain two distinct T-cell populations that did not express the T-cell activation markers, CD69, CD25 and human leukocyte antigen (HLA)-DR: CD69CD25HLA-DR small cells (nonblasts) that had not proliferated in vitro following mitogen stimulation and CD69CD25HLA-DR large cells (which we here call transitional blasts) that had proliferated. The cells were then reactivated with latency-reversing agents and either luciferase or EGFP quantified., Results: Inducible luciferase expression, consistent with latent infection, was observed in nonblasts and transitional blasts following stimulation with either phorbol-myristate-acetate/phytohemagglutinin (3.8 ± 1 and 2.9 ± 0.5 fold above dimethyl sulfoxide, respectively) or romidepsin (2.1 ± 0.6 and 1.8 ± 0.2 fold above dimethyl sulfoxide, respectively). Constitutive expression of luciferase was higher in transitional blasts compared with nonblasts. Using wild-type full-length EGFP reporter virus, inducible virus was observed in nonblasts but not in transitional blasts. No significant difference was observed in the response to latency-reversing agents in either nonblasts or transitional blasts., Conclusion: HIV latency can be established in vitro in resting T cells that have not proliferated (nonblasts) and blasts that have proliferated (transitional blasts). This model could potentially be used to assess new strategies to eliminate latency.

Disseminated histoplasmosis (DH), an endemic mycosis caused by the dimorphic fungus Histoplasma capsulatum, is a life-threatening infection in immunocompromised hosts. A patient with newly-diagnosed human immunodeficiency virus (HIV) infection presented with a violaceous, raised, indurated, pruritic rash over the face, arms and trunk on a background of significant weight loss, fevers with sweats, diarrhoea and worsening shortness of breath. His CD4+ T cell count was 14 cells/µl (12%). Histoplasmosis was diagnosed from histology, fungal stain and culture of skin biopsy. In addition to DH, he was found to have Pneumocystis jiroveci pneumonia and multi-resistant Salmonella choleraesuis bacteraemia. He improved with treatment with antibiotics and was commenced on conventional itraconazole, orally. Antiretroviral therapy was commenced soon after. He was unable to achieve therapeutic levels with the conventional formulation due to gastrointestinal side effects and had ongoing fevers. A newer formulation of oral itraconazole with improved bioavailability was commenced. He achieved therapeutic drug levels and had no further intolerance. His fevers settled and the rash improved. He has now completed one year of treatment and is well. To our knowledge this is the first case of moderate DH in an advanced HIV patient treated successfully with oral itraconazole with improved bioavailability. [ABSTRACT FROM AUTHOR]