Past and future of HIV infection. A document based on expert opinion

HIV infection is now almost 40 years old. In this time, along with the catastrophe and tragedy that it has entailed, it has also represented the capacity of modern society to take on a challenge of this magnitude and to transform an almost uniformly lethal disease into a chronic illness, compatible with a practically normal personal and relationship life. This anniversary seemed an ideal moment to pause and reflect on the future of HIV infection, the challenges that remain to be addressed and the prospects for the immediate future. This reflection has to go beyond merely technical approaches, by specialized professionals, to also address social and ethical aspects. For this reason, the Health Sciences Foundation convened a group of experts in different aspects of this disease to discuss a series of questions that seemed pertinent to all those present. Each question was presented by one of the participants and discussed by the group. The document we offer is the result of this reflection.

Pathogenesis and treatment of HIV infection: the cellular, the immune system and the neuroendocrine systems perspective

Infections with HIV represent a great challenge for the development of strategies for an effective cure. The spectrum of diseases associated with HIV ranges from opportunistic infections and cancers to systemic physiological disorders like encephalopathy and neurocognitive impairment. A major progress in controlling HIV infection has been achieved by highly active antiretroviral therapy (HAART). However, HAART does neither eliminate the virus reservoirs in form of latently infected cells nor does it completely reconstitute immune reactivity and physiological status. Furthermore, the failure of the STEP vaccine trial and the only marginal efficacies of the RV144 trial together suggest that the causal relationships between the complex sets of viral and immunological processes that contribute to protection or disease pathogenesis are still poorly understood. Here, we provide an up-to-date overview of HIV-host interactions at the cellular, the immune system and the neuroendocrine systems level. Only by integrating this multi-level knowledge one will be able to handle the systems complexity and develop new methodologies of analysis and prediction for a functional restoration of the immune system and the health of the infected host.

A Case of Hyper-reactive Malarial Splenomegaly. The Role of Rapid Antigen-detecting and PCR-based Tests

Hyper-reactive malarial splenomegaly (HMS) - originally referred to as tropical splenomegaly syndrome - is characterized by a massive splenomegaly, high titres of anti-malarial antibodies and polyclonal IgM hypergammaglobulinemia. It is believed to be a consequence of an aberrant immunological response to prolonged exposure to malarial parasites. Although it is a frequent disease in the tropics, it is infrequent in western countries and is only seen in long-term residents from endemic areas. We describe the case of a 67-year-old Spanish man, a missionary in Cameroon for 30 years, who presented with a clinical history that fulfilled the diagnosis of HMS. We discuss the role and importance of PCR-based techniques in demonstrating lowgrade malarial parasitemia and the usefulness of new rapid antigen-detecting dipstick tests.

Definition of the Mamu A*01 peptide binding specificity: application to the identification of wild-type and optimized ligands from simian immunodeficiency virus regulatory proteins

Single amino acid substitution analogs of the known Mamu A*01 binding peptide gag 181-190 and libraries of naturally occurring sequences of viral or bacterial origin were used to rigorously define the peptide binding motif associated with Mamu A*01 molecules. The presence of S or T in position 2, P in position 3, and hydrophobic or aromatic residues at the C terminus is associated with optimal binding capacity. At each of these positions, additional residues are also tolerated but associated with significant decreases in binding capacity. The presence of at least two preferred and one tolerated residues at the three anchor positions is necessary for good Mamu A*01 binding; optimal ligand size is 8-9 residues. This detailed motif has been used to map potential epitopes from SIVmac239 regulatory proteins and to engineer peptides with increased binding capacity. A total of 13 wild type and 17 analog candidate epitopes were identified. Furthermore, our analysis reveals a significantly lower than expected frequency of epitopes in early regulatory proteins, suggesting a possible evolutionary- and/or immunoselection directed against variants of viral products that contain CTL epitopes.