RESUMO
Recent studies have demonstrated that genetically modified hematopoietic stem cells (HSCs) can reduce HIV viremia. We have developed an HIV/AIDS-patient model in Simian/human immunodeficiency virus (SHIV)-infected pigtailed macaques that are stably suppressed on antiretroviral therapy (ART: raltegravir, emtricitabine and tenofovir). Following SHIV infection and ART, animals undergo autologous HSC transplantation (HSCT) with lentivirally transduced cluster of differentiation (CD)34(+) cells expressing the mC46 anti-HIV fusion protein. We show that SHIV(+), ART-treated animals had very low gene marking levels after HSCT. Pretransduction CD34(+) cells contained detectable levels of all three ART drugs, likely contributing to the low gene transfer efficiency. Following HSCT recovery and the cessation of ART, plasma viremia rebounded, indicating that myeloablative total body irradiation cannot completely eliminate viral reservoirs after autologous HSCT. The kinetics of recovery following autologous HSCT in SHIV(+), ART-treated macaques paralleled those observed following transplantation of control animals. However, T-cell subset analyses demonstrated a high percentage of C-C chemokine receptor 5 (CCR5)-expressing CD4(+) T-cells after HSCT. These data suggest that an extended ART interruption time may be required for more efficient lentiviral transduction. To avoid complications associated with ART interruption in the context of high percentages of CD4(+)CCR5(+)T-cells after HSCT, the use of vector systems not impaired by the presence of residual ART may also be beneficial.
Assuntos
Terapia Antirretroviral de Alta Atividade , Terapia Genética , Vetores Genéticos/genética , Células-Tronco Hematopoéticas/metabolismo , Lentivirus/genética , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/imunologia , Transdução Genética , Animais , Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Imunofenotipagem , Contagem de Linfócitos , Macaca nemestrina , Síndrome de Imunodeficiência Adquirida dos Símios/terapia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/efeitos da radiação , Subpopulações de Linfócitos T/virologia , Transgenes , Condicionamento Pré-Transplante , Carga ViralRESUMO
Biomarkers are most frequently proteins that are measured in the blood. Their development largely relies on antibody creation to test the protein candidate performance in blood samples of diseased versus nondiseased patients. The creation of such antibody assays has been a bottleneck in biomarker progress due to the cost, extensive time, and effort required to complete the task. Targeted proteomics is an emerging technology that is playing an increasingly important role to facilitate disease biomarker development. In this study, we applied a SRM-based targeted proteomics platform to directly detect candidate biomarker proteins in plasma to evaluate their clinical utility for pancreatic cancer detection. The characterization of these protein candidates used a clinically well-characterized cohort that included plasma samples from patients with pancreatic cancer, chronic pancreatitis, and healthy age-matched controls. Three of the five candidate proteins, including gelsolin, lumican, and tissue inhibitor of metalloproteinase 1, demonstrated an AUC value greater than 0.75 in distinguishing pancreatic cancer from the controls. In addition, we provide an analysis of the reproducibility, accuracy, and robustness of the SRM-based proteomics platform. This information addresses important technical issues that could aid in the adoption of the targeted proteomics platform for practical clinical utility.
