P5.074 Immune Activation After Stimulation with Cryptococcus Neoformans Antigens Pre and Post ART Initiation in HIV-1 Positive Ugandans. (13th July 2013)

• Record Type: Journal Article
• Authors: Sanya, R N; Chatterjea, D; Akampurrira, A; Naluyima, P; Meya, D B; Rowe, J H; Cham, F; Boulware, D R
• Is Part Of: Sexually transmitted infections. Volume 89(2013)Supplement 1
• Page Start: A357
• Page End: A358
• Publication Date: 2013-07-13
• Subjects: Cryptococcus meningitis -- HIV antiretroviral therapy (ART) -- immune reconstitution inflammatory syndrome (IRIS); Sexually transmitted diseases -- Periodicals; HIV infections -- Periodicals; 616.951005
• DOI: 10.1136/sextrans-2013-051184.1118
• Languages: English
• ISSNs: 1368-4973

Abstract

Abstract : Background: Cryptococcus meningitis immune reconstitution inflammatory syndrome (CM-IRIS) is a medical condition that complicates recovery from immunodeficiency as a result of anti retroviral therapy (ART) in patients living with Human Immunodeficiency Virus type 1 (HIV-1) in the sub Sahara Africa region. Methods: This study investigated CD4 T cell immune activation based on intracellular IFN-γ and Ki-67 expression, after ex-vivo cryptococcal antigen stimulation of whole blood samples taken from HIV-1 positive adult patients infected with or without cryptococcal meningitis, initiated on ART. Results: In the CM positive group at pre-ART visit; stimulation with C.neoformans crude cell wall (CW) induced a significant increase in CD4 IFN-γ production (p < 0.05****), as compared to C.neoformans glucuronoxylomannan (GXM) polysaccharide antigen (p < 0.05*), whilst C.neoformans mannoprotein (MP) stimulation failed to induce greater than baseline IFN-γ expression. The effector memory T cell subset was the major contributor to the IFN-γ elevation exhibited in CW stimulated samples. Interestingly, T cell responses to CW were found to be significantly higher in the CM positive group compared to the CM negative group (p < 0.05*). Furthermore, stimulation with CW and GXM exhibited higher frequency of terminally differentiated effector memory T cells (TDEMS) compared to either negative control or MP stimulation. Conclusion: Immune activation of CD4 T cells can be achieved by C.neoformans CW rather than purified MP antigen, by inducing the effector memory subset to produce IFN-γ.