The failure of HAART to cure the HIV-1/AIDS complex. Suggestions to add integrase inhibitors as complementary virostatics, and to replace their continuous long combination applications by short sequences differing by drug rotations

Extracellular vesicles expressing a single-chain variable fragment of an HIV-1 specific antibody selectively target Env+ tissues

Rationale: Antiretroviral therapy can effectively suppress HIV-1 replication in the peripheral blood to an undetectable level. However, elimination of the latent virus in reservoirs remains a challenge and is a major obstacle in the treatment of HIV-1-infected patients. Exosomes exhibit huge promise as an endogenous drug delivery nanosystem for delivering drugs to solid tissues given their unique properties, including low immunogenicity, innate stability, high delivery efficiency, and most importantly the ability to penetrate solid tissues due to their lipophilic properties. Methods: We engineered and expressed the scFv of a high affinity HIV-1-specific monoclonal antibody, 10E8, on the exosomal surface (10E8scFv-exos). Subsequently, the 10E8scFv-exos were loaded with curcumin (Cur), a chemical that kills HIV-1-infected cells, or miR-143, an apoptosis-inducing miRNA. We tested the ability of 10E8scFv-exos to deliver cargo to Env+ target cells and tissues, as well as their ability to suppress HIV-1 infection. Results: 10E8scFv-exos efficiently targeted CHO cells expressing a trimeric gp140 on their surface (Env+ cells) in vitro, as demonstrated by confocal imaging and flow cytometry. 10E8scFv-exos loaded with Cur or miR-143 showed specific killing of Env+ cells. In addition, 10E8scFv-exos loaded with Cur or miR-143 could suppress p24 expression in an HIV-1 latency cell line ACH2 and in PBMCs from an ART-treated HIV-1-infected patient. In an NCG mouse model grafted with tumorigenic Env+ CHO cells and which had developed solid tissue tumors, intravenously injected 10E8scFv-exos targeted the Env-expressing tissues and delivered Cur to induce a strong suppression of the Env+ tumor growth with low toxicity. Conclusion: In principle, engineered exosomes can deliver anti-HIV agents to solid tissues by specifically targeting cells expressing viral envelop proteins and inducing cell killing, suggesting that such an approach could be developed for eradicating virus-infected cells in tissue reservoirs.

Discrimination of benign and neoplastic mucosa with a high-resolution microendoscope (HRME) in head and neck cancer

BACKGROUND

The efficacy of ablative surgery for head and neck squamous cell carcinoma (HNSCC) depends critically on obtaining negative margins. Although intraoperative "frozen section" analysis of margins is a valuable adjunct, it is expensive, time-consuming, and highly dependent on pathologist expertise. Optical imaging has potential to improve the accuracy of margins by identifying cancerous tissue in real time. Our goal was to determine the accuracy and inter-rater reliability of head and neck cancer specialists using high-resolution microendoscopic (HRME) images to discriminate between cancerous and benign mucosa.

METHODS

Thirty-eight patients diagnosed with head and neck squamous cell carcinoma (HNSCC) were enrolled in this single-center study. HRME was used to image each specimen after application of proflavine, with concurrent standard histopathologic analysis. Images were evaluated for quality control, and a training set containing representative images of benign and neoplastic tissue was assembled. After viewing training images, seven head and neck cancer specialists with no previous HRME experience reviewed 36 test images and were asked to classify each.

RESULTS

The mean accuracy of all reviewers in correctly diagnosing neoplastic mucosa was 97% (95% confidence interval (CI), 94-99%). The mean sensitivity and specificity were 98% (97-100%) and 92% (87-98%), respectively. The Fleiss kappa statistic for inter-rater reliability was 0.84 (0.77-0.91).

CONCLUSIONS

Medical professionals can be quickly trained to use HRME to discriminate between benign and neoplastic mucosa in the head and neck. With further development, the HRME shows promise as a method of real-time margin determination at the point of care.

High-resolution imaging in Barrett's esophagus: a novel, low-cost endoscopic microscope

BACKGROUND

This report describes the clinical evaluation of a novel, low-cost, high-resolution endoscopic microscope for obtaining fluorescent images of the cellular morphology of the epithelium of regions of the esophagus with Barrett's metaplasia. This noninvasive point imaging system offers a method for obtaining real-time histologic information during endoscopy.

OBJECTIVE

The objective of this study was to compare images taken with the fiberoptic endoscopic microscope with standard histopathologic examination.

DESIGN

Feasibility study.

SETTING

The University of Texas M.D. Anderson Cancer Center Department of Gastroenterology. PATIENTS, INTERVENTIONS, AND MAIN OUTCOME MEASUREMENTS: The tissue samples studied in this report were obtained by endoscopic resection from patients with previous diagnoses of either high-grade dysplasia or esophageal adenocarcinoma.

RESULTS

Three distinct tissue types were observed ex vivo with the endoscopic microscope: normal squamous mucosa, Barrett's metaplasia, and high-grade dysplasia. Squamous tissue was identified by bright nuclei surrounded by dark cytoplasm in an ordered pattern. Barrett's metaplasia could be identified by large glandular structures with intact nuclear polarity. High-grade dysplasia was visualized as plentiful, irregular glandular structures and loss of nuclear polarity. Standard histopathologic examination of study samples confirmed the results obtained by the endoscopic microscope.

LIMITATIONS

The endoscopic microscope probe had to be placed into direct contact with tissue.

CONCLUSIONS

It was feasible to obtain high-resolution histopathologic information using the endoscopic microscope device. Future improvement and integration with widefield endoscopic techniques will aid in improving the sensitivity of detection of dysplasia and early cancer development in the esophagus.

Design, synthesis and biological evaluation of heteroaryl diketohexenoic and diketobutanoic acids as HIV-1 integrase inhibitors endowed with antiretroviral activity

Highly active anti-retroviral therapy (HAART) using reverse transcriptase (RT) and protease (PR) inhibitors and, more recently, inhibitors of the fusion is currently the best clinical approach in combating acquired immunodeficiency syndrome (AIDS), caused by infection from human immunodeficiency virus type 1 (HIV-1). However, this therapy does not completely eradicate the virus, so that resistant strains easily emerge. The above problem calls urgently for research on inhibitors of further viral targets such as integrase (IN), the third enzyme produced by HIV. Recently, our research group was engaged in studies on conformationally restrained cinnamoyl compounds related to curcumin as anti-IN agents. Compounds containing both a 3,4,5-trihydroxyphenyl group and a carboxylic acid function were potent IN inhibitors active against viral replication. More recently, a promising new class of inhibitors synthesized by Merck Company has emerged, which contain aryldiketoacid (ADK) functionality. The ADKs selectively inhibited the stand transfer (ST) step of integration and were proven to be effective IN inhibitors in vivo. Our interest in the field of IN inhibitors led us to design pyrrole and indole derivatives containing both a cinnamoyl moiety and a diketoacid group. A number of the cited derivatives were proven potent IN inhibitors, which selectively inhibited the ST step at submicromolar concentrations and were effective against virus replication in HIV-1 infected cells.

The roles of adoptive and active forms of immunotherapy in the cure of children suffering from acute lymphoid leukemia: a) underestimation of active immunotherapy benefit, b) its immunogenetic indications to select sensitive patients, hence prevent chemotherapy's late effects

Children's acute lymphoid leukemia (ALL) chemotherapy started in 1948 with antimetabolites combined with steroids. It was enriched in 1959 with vincristine and cyclophosphamide and, in 1970, with daunomycin. It induced more and more apparently what were called complete remissions, and prolonged more and more the survivals without reducing however, until 1973, the (100%) mortality. It started to reduce it at the fifth year, to 20 and even 40% between 1973 and 1976, due to progressive and maximal intensification and duration of chemotherapy. It is in the same period that we proposed to apply in ALL remissions after relapses and in the first remissions of the most malignant type, allogeneic bone marrow grafts; we published the first success in human ALL in 1963, and clinically observed the same actions as those described experimentally: cytoablation of both leukemia and hematopoiesis, the latter being restored by the graft, whose reaction versus the residual neoplastic cells (called graft versus leukemia or GvL) appeared to be able to often eradicate them, at the cost however of a graft-versus-host reaction (both reactions sharing the same mechanism). One of us became a member of the Committee of the International Bone Marrow Transplant Registry, whose results showed the improvement in the prognosis of the aggressive form of ALL. The intensity and length established for chemotherapy for the most severe form of children's ALL have often been applied to the intermediary and to the least aggressive ones. The global 5-year survival increased to 60% between 1976 and 1984, and is around 80% today. But the registration of late debilitating or malignant effects of chemotherapy toxicities makes us wonder if some patients have not received an excessively intense and long application of cytostatics (often combined with ionizing radiations on CNS). In fact, the patients belonging to some HLA phenotypes (A33 and B17) have appeared to be especially often cured with active immunotherapy (killed leukemic cells and/or BCG), whose action was shown by specific cytotoxicity amplification, which was applied after short adjuvant chemotherapy, and hence is able to reduce the long chemotherapy incidence of debilitating or malignant late effects. Sakurai's group confirmed our absence of late relapses after ALL active immunotherapy, which contrasts with their risk after maintenance chemotherapy, whose minimal residual disease is a worrisome stumbling block to the cure.