Andrea Brambilla

Efficacy of Low-Dose Intermittent Subcutaneous Interleukin (IL)–2 in Antiviral Drug–Experienced Human Immunodeficiency Virus–Infected Persons with Detectable Virus Load: A Controlled Study of 3 IL-2 Regimens with Antiviral Drug Therapy

To evaluate the safety and efficacy of 3 regimens of intermittent subcutaneous (sc) interleukin (IL)--2 in a phase 2 study, 61 antiviral drug-experienced human immunodeficiency virus (HIV)--positive patients were randomly assigned to one of the following study arms: antiretroviral therapy (ART) plus IL-2 (12 million IU [MIU] by continuous intravenous infusion, followed by 7.5 MIU twice a day, sc, every 8 weeks); ART plus IL-2 (7.5 MIU twice a day, sc, every 8 weeks); ART plus IL-2 (3 MIU twice a day, sc, every 4 weeks); or ART alone. A significant increase of circulating CD4 cells was observed in IL-2--treated subjects, compared with those given ART alone. Low doses of IL-2 were better tolerated. Despite the incomplete suppression of viral replication, IL-2 with ART did not increase either plasma viremia or cell-associated HIV DNA levels. Low doses of intermittent sc IL-2 induced a stable increase of peripheral CD4 cells that was indistinguishable from those associated with higher, less well-tolerated doses of IL-2.

CCR2-64I Polymorphism, Syncytium-Inducing Human Immunodeficiency Virus Strains, and Disease Progression

NOTE. Numerical values are numbers of individuals. NSI, non–syncytium inducing; SFMHS, San Francisco Men’s Health Study; SI, syncytium inducing. a Fisher’s exact P value. does not predict the ability of an assay to detect C. pneumoniae in tissues. We agree with Valassina et al. [1] that the presence of C. pneumoniae DNA alone in arterial specimens is insufficient proof of the presence of viable organisms in vascular tissue; however, cultural isolation of the bacterium from atherosclerotic plaques has been reported repeatedly [5, 6]. Furthermore, culture-derived data are in accordance with the results of our study on C. pneumoniae RNA in carotid plaques. Regarding the suggestion that inflammatory mechanisms such as molecular mimicry or induction of metabolic mechanisms are responsible for atheroma formation, rather than the presence of viable bacteria, we believe this to be partially true. However, the results of studies in animal models indicate that the presence of viable bacteria in vascular tissues is an essential element in the association between C. pneumoniae and development of atherosclerotic lesions [7].

Transmission of HIV-1 and HCV by head-butting

Two men who had never met before had a fight as a consequence of a motor car accident. One, who was HIV-1 positive, head-butted the other who was wearing metal-framed spectacles on his forehead. The spectacles left imprints on the foreheads of both men, and there was copious bleeding. The man who was head-butted tested negative for HIV-1 3 days after the fight. 14 days later, however, he developed symptoms consistent with primary HIV-1 infection. About 3 months after the assault, he also had acute type B hepatitis; at which time he was found positive for antibodies against all the major HIV-1 structural proteins, although HIV-1 EIA was negative, and with CD4 T-cell counts of 606 10/L. The assailant had a history of intravenous-drug use. In May, 1990, he reported syringe exchange and sexual intercourse with an HIV-seropositive woman. At the time, he tested negative for antibodies against HIV-1 p24 antigen. Positive tests for HIV-1, hepatitis C virus (HCV), and hepatitis B virus (HBV) were found in May, 1991, when his CD4 T-cell count was 720 10/L. His CD4 cell counts were 124 10/L at the time of the fight. Sequencing of a 183 base pair of the gp120 V3 env region of DNA from both men’s peripheral blood mononuclear cells was done 126 days after the fight. Nucleotide sequence distances of the men and four Italian HIV-1 infected mother/infant pairs living in the same region were calculated with the DNADIST program of the 3.572c Phylogeny Inference Package. The average distance of the men (2·80 [SD 0·26]) was similar to those calculated for the mother/infant pairs, which ranged from 1·91 (0·36) to 7·05 (0·66). By contrast, distances between either of the men and mothers and infants were those typical of epidemiologically unlinked infections (variability range from 9·37% to 18·44%). The men’s pairwise distances were significantly different (p<0·0025) from the distances between either of them and the less divergent control, suggesting that the similarity between the men’s HIV-1 DNA was not random. The skin injuries in the man likely provided HIV-1 and HBV with a direct access to the bloodstream. Although the assailant was also infected with HCV, the other man tested negative for HCV 4 months after the accident. Parenteral exposure via blood or blood products leads to HCV infection in most cases, particularly at high levels of viraemia. The head-butter’s HCV viral burden was less than 1000 copies/mL plasma, which may explain the lack of HCV transmission.

Exosomes From Human Cardiac Progenitor Cells for Therapeutic Applications: Development of a GMP-Grade Manufacturing Method

Exosomes, nanosized membrane vesicles secreted by cardiac progenitor cells (Exo-CPC), inhibit cardiomyocyte apoptosis under stress conditions, promote angiogenesis in vitro, and prevent the early decline in cardiac function after myocardial infarction in vivo in preclinical rat models. The recognition of exosome-mediated effects has moved attempts at developing cell-free approaches for cardiac repair. Such approaches offer major advantages including the fact that exosomes can be stored as ready-to-use agents and delivered to patients with acute coronary syndromes. The aim of the present work was the development of a good manufacturing practice (GMP)-grade method for the large-scale preparation of Exo-CPC as a medicinal product, for a future clinical translation. A GMP-compliant manufacturing method was set up, based on large-scale cell culture in xeno-free conditions, collection of up to 8 l of exosome-containing conditioned medium and isolation of Exo-CPC through tangential flow filtration. Quality control tests were developed and carried out to evaluate safety, identity, and potency of both cardiac progenitor cells (CPC) as cell source and Exo-CPC as final product (GMP-Exo-CPC). CPC, cultured in xeno-free conditions, showed a lower doubling-time than observed in research-grade condition, while producing exosomes with similar features. Cells showed the typical phenotype of mesenchymal progenitor cells (CD73/CD90/CD105 positive, CD14/CD20/CD34/CD45/HLA-DR negative), and expressed mesodermal (TBX5/TBX18) and cardiac-specific (GATA4/MESP1) transcription factors. Purified GMP-Exo-CPC showed the typical nanoparticle tracking analysis profile and expressed main exosome markers (CD9/CD63/CD81/TSG101). The GMP manufacturing method guaranteed high exosome yield (>1013 particles) and consistent removal (≥97%) of contaminating proteins. The resulting GMP-Exo-CPC were tested for safety, purity, identity, and potency in vitro, showing functional anti-apoptotic and pro-angiogenic activity. The therapeutic efficacy was validated in vivo in rats, where GMP-Exo-CPC ameliorated heart function after myocardial infarction. Our standardized production method and testing strategy for large-scale manufacturing of GMP-Exo-CPC open new perspectives for reliable human therapeutic applications for acute myocardial infarction syndrome and can be easily applied to other cell sources for different therapeutic areas.