Trehalose Inhibits Human Immunodeficiency Virus Type 1 Infection in Primary Human Macrophages and CD4+ T Lymphocytes through Two Distinct Mechanisms.

Autophagy is a highly conserved recycling pathway that promotes cell survival during periods of stress. We previously reported that induction of autophagy through the inhibition of the mechanistic target of rapamycin (MTOR) inhibits HIV replication in human macrophages and CD4+ T lymphocytes (T cells). However, the inhibition of MTOR has modulatory effects beyond autophagy that might affect viral replication. Here, we examined the effect on HIV replication of trehalose, a nontoxic, nonreducing disaccharide that induces autophagy through an MTOR-independent mechanism. Treatment of HIV-infected macrophages and T cells with trehalose inhibited infection in a dose-dependent manner. Uninfected and HIV-infected macrophages and T cells treated with trehalose exhibited increased markers of autophagy, including LC3B lipidation with further accumulation following bafilomycin A1 treatment, and increased levels of LAMP1, LAMP2, and RAB7 proteins required for lysosomal biogenesis and fusion. Moreover, the inhibition of HIV by trehalose was significantly reduced by knockdown of ATG5 Additionally, trehalose downregulated the expression of C-C motif chemokine receptor 5 (CCR5) in T cells and CD4 in both T cells and macrophages, which reduced HIV entry in these cells. Our data demonstrate that the naturally occurring sugar trehalose at doses safely achieved in humans inhibits HIV through two mechanisms: (i) decreased entry through the downregulation of CCR5 in T cells and decreased CD4 expression in both T cells and macrophages and (ii) degradation of intracellular HIV through the induction of MTOR-independent autophagy. These findings demonstrate that cellular mechanisms can be modulated to inhibit HIV entry and intracellular replication using a naturally occurring, nontoxic sugar.IMPORTANCE Induction of autophagy through inhibition of MTOR has been shown to inhibit HIV replication. However, inhibition of the mechanistic target of rapamycin (MTOR) has cellular effects that may alter HIV infection through other mechanisms. Here, we examined the HIV-inhibitory effects of the MTOR-independent inducer of autophagy, trehalose. Of note, we identified that in addition to the inhibition of the intracellular replication of HIV by autophagy, trehalose decreased viral entry in human primary macrophages and CD4+ T cells through the downregulation of C-C motif chemokine receptor 5 (CCR5) in T cells and CD4 in both T cells and macrophages. Thus, we showed that trehalose uniquely inhibits HIV replication through inhibition of viral entry and intracellular degradation in the two most important target cells for HIV infection.

How Well Do EMS Providers Predict Intracranial Hemorrhage in Head-Injured Older Adults?

Objective: To evaluate the accuracy of emergency medical services (EMS) provider judgment for traumatic intracranial hemorrhage (tICH) in older patients following head trauma in the field. We also compared EMS provider judgment with other sets of field triage criteria. Methods: This was a prospective observational cohort study conducted with five EMS agencies and 11 hospitals in Northern California. Patients 55 years and older who experienced blunt head trauma were transported by EMS between August 1, 2015 and September 30, 2016, and received an initial cranial computed tomography (CT) imaging, were eligible. EMS providers were asked, "What is your suspicion for the patient having intracranial hemorrhage (bleeding in the brain)?" Responses were recorded as ordinal categories (<1%, 1-5%, >5-10%, >10-50%, or >50%) and the incidences of tICH were recorded for each category. The accuracy of EMS provider judgment was compared to other sets of triage criteria, including current field triage criteria, current field triage criteria plus multivariate logistical regression risk factors, and actual transport. Results: Among the 673 patients enrolled, 319 (47.0%) were male and the median age was 75 years (interquartile range 64-85). Seventy-six (11.3%) patients had tICH on initial cranial CT imaging. The increase in EMS provider judgment correlated with an increase in the incidence of tICH. EMS provider judgment had a sensitivity of 77.6% (95% CI 67.1-85.5%) and a specificity of 41.5% (37.7-45.5%) when using a threshold of 1% or higher suspicion for tICH. Current field triage criteria (Steps 1-3) was poorly sensitive (26.3%, 95% CI 17.7-37.2%) in identifying tICH and current field trial criteria plus multivariate logistical regression risk factors was sensitive (97.4%, 95% CI 90.9-99.3%) but poorly specific (12.9%, 95% CI 10.4-15.8%). Actual transport was comparable to EMS provider judgment (sensitivity 71.1%, 95% CI 60.0-80.0%; specificity 35.3%, 95% CI 31.6-38.3%). Conclusions: As EMS provider judgment for tICH increased, the incidence for tICH also increased. EMS provider judgment, using a threshold of 1% or higher suspicion for tICH, was more accurate than current field triage criteria, with and without additional risk factors included.

Rapid Multiplex Testing for Upper Respiratory Pathogens in the Emergency Department: A Randomized Controlled Trial.

BACKGROUND: Acute upper respiratory tract infections are a common cause of emergency department (ED) visits and often result in unnecessary antibiotic treatment. METHODS: We conducted a randomized clinical trial to evaluate the impact of a rapid, multipathogen respiratory panel (RP) test vs usual care (control). Patients were eligible if they were ≥12 months old, had symptoms of upper respiratory infection or influenza-like illness, and were not on antibiotics. The primary outcome was antibiotic prescription; secondary outcomes included antiviral prescription, disposition, and length of stay (ClinicalTrials.gov# NCT02957136). RESULTS: Of 191 patients enrolled, 93 (49%) received RP testing; 98 (51%) received usual care. Fifty-three (57%) RP and 7 (7%) control patients had a virus detected and reported during the ED visit (P = .0001). Twenty (22%) RP patients and 33 (34%) usual care patients received antibiotics during the ED visit (-12%; 95% confidence interval, -25% to 0.4%; P = .06/0.08); 9 RP patients received antibiotics despite having a virus detected. The magnitude of antibiotic reduction was greater in children (-19%) vs adults (-9%, post hoc analysis). There was no difference in antiviral use, length of stay, or disposition. CONCLUSIONS: Rapid RP testing was associated with a trend toward decreased antibiotic use, suggesting a potential benefit from more rapid viral tests in the ED. Future studies should determine if specific groups are more likely to benefit from testing and evaluate the relative cost and effectiveness of broad testing, focused testing, and a combined diagnostic and antimicrobial stewardship approach.