Human immunodeficiency virus (HIV) is a causative agent of acquired immune deficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) can slow down the replication of HIV-1, leading to an improvement in the survival of HIV-1-infected patients. However, drug toxicities and poor drug administration has led to the emergence of a drug-resistant strain. HIV-1 immunotherapy has been continuously developed, but antibody therapy and HIV vaccines take time to improve its efficiency and have limitations. HIV-1-specific chimeric antigen receptor (CAR)-based immunotherapy founded on neutralizing antibodies is now being developed. In HIV-1 therapy, anti-HIV chimeric antigen receptors showed promising data in the suppression of HIV-1 replication; however, autologous transfusion is still a problem. This has led to the development of effective peptides and proteins for an alternative HIV-1 treatment. In this paper, we provide a comprehensive review of potent anti-HIV-1 peptides and proteins that reveal promising therapeutic activities. The inhibitory mechanisms of each therapeutic molecule in the different stages of the HIV-1 life cycle will be discussed herein.
AnkGAG1D4 is an artificial ankyrin repeat protein which recognizes the capsid protein (CA) of the human immunodeficiency virus type 1 (HIV-1) and exhibits the intracellular antiviral activity on the viral assembly process. Improving the binding affinity of AnkGAG1D4 would potentially enhance the AnkGAG1D4-mediated antiviral activity. To augment the affinity of AnkGAG1D4 scaffold towards its CA target, through computational predictions and experimental designs. Three dimensional structure of the binary complex formed by AnkGAG1D4 docked to the CA was used as a model for van der Waals (vdW) binding energy calculation. The results generated a simple guideline to select the amino acids for modifications. Following the predictions, modified AnkGAG1D4 proteins were produced and further evaluated for their CA-binding activity, using ELISA-modified method and bio-layer interferometry (BLI). Tyrosine at position 56 (Y56) in AnkGAG1D4 was experimentally identified as the most critical residue for CA binding. Rational substitutions of this residue diminished the binding affinity. However, vdW calculation preconized to substitute serine for tyrosine at position 45. Remarkably, the affinity for the viral CA was significantly enhanced in AnkGAG1D4-S45Y mutant, with no alteration of the target specificity. The S-to-Y mutation at position 45, based on the prediction of interacting amino acids and on vdW binding energy calculation, resulted in a significant enhancement of the affinity of AnkGAG1D4 ankyrin for its CA target. AnkGAG1D4-S45Y mutant represented the starting point for further construction of variants with even higher affinity towards the viral CA, and higher therapeutic potential in the future.
A new generation of artificial proteins, derived from alpha-helicoidal HEAT-like repeat protein scaffolds (αRep), was previously characterized as an effective source of intracellular interfering proteins. In this work, a phage-displayed library of αRep was screened on a region of HIV-1 Gag polyprotein encompassing the C-terminal domain of the capsid, the SP1 linker and the nucleocapsid. This region is known to be essential for the late steps of HIV-1 life cycle, Gag oligomerization, viral genome packaging and the last cleavage step of Gag, leading to mature, infectious virions. Two strong αRep binders were isolated from the screen, αRep4E3 (32 kDa; 7 internal repeats) and αRep9A8 (28 kDa; 6 internal repeats). Their antiviral activity against HIV-1 was evaluated in VLP-producer cells and in human SupT1 cells challenged with HIV-1. Both αRep4E3 and αRep9A8 showed a modest but significant antiviral effects in all bioassays and cell systems tested. They did not prevent the proviral integration reaction, but negatively interfered with late steps of the HIV-1 life cycle: αRep4E3 blocked the viral genome packaging, whereas αRep9A8 altered both virus maturation and genome packaging. Interestingly, SupT1 cells stably expressing αRep9A8 acquired long-term resistance to HIV-1, implying that αRep proteins can act as antiviral restriction-like factors.
Coronavirus disease 2019 (COVID-19) caused by an infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been recognized as one of the biggest problems to human health worldwide. The potential strategy to control the spreading of the virus is awareness of infection status, especially among non-patient under investigation (non-PUI). Additionally, implementing gathering control and suspending “social distancing” are key to a decrease in the chance of infection. This study aimed to conduct and implement the pilot management system for COVID-19 testing and to perform proactive screening test among non-PUI people in Phayao Province, the rural area of Thailand. This was a cross-sectional study. People who could access websites- or mobile applications were eligible to be recruited into the study. An online questionnaire was developed to collect information on socio-demographics, medical conditions and symptoms related to COVID-19 from participants who were living in Phayao Province from July to August 2020. 200 participants performed self-evaluation but only 143 (71.5%) participants booked an appointment and visited the collecting site to get the test. There were 25 (9%) participants being at high risk of infection. The nasopharyngeal/throat swabs were collected and proceeded to determine a presence of SARS-CoV-2 using RT-PCR. Of all, none was found to be positive for SARS-CoV-2. In conclusion, this developed management system would be an important tool for managing laboratory testing during the COVID-19 outbreak by means of reducing the chance of infection in the epidemic situation. This proactive screening system can also be applied for other medical testing and services.
Early diagnosis is key to achieving the goal of eliminating transmission of HIV and hepatitis B and C. We assessed the uptake, acceptability and interpretability of self-testing using a 3-in-1 rapid diagnostic test (RDT) in facility-based services. Stand-alone testing services were provided free of charge to consenting individuals aged ≥15 years in five facilities in northern Thailand. Clients were invited to choose between self-testing by fingerprick or venepuncture by a healthcare worker (HCW). In each facility, several clients could simultaneously self-test in separate private areas using TriQuik™ (Genlantis, San Diego, CA, USA), a single immunochromatographic cassette detecting HIV-1/2 antibody, hepatitis B surface antigen (HBsAg) and hepatitis C antibody (HCAb). An interactive program on a tablet computer was developed to collect socio-demographic, behavioural and satisfaction data and provide information to guide the self-test process, including video instructions, results interpretation and a picture of the cassette for immediate remote review by the HCW. When the HCW interpreted an HIV self-test as positive, the HCW collected blood by venepuncture for immediate confirmation. Between October 2020 and April 2022, 4119 clients presented for testing for the first time as part of the project. Of them, 3462 (84.0%) opted for self-testing. Among self-testers, 1801 (52.0%) were born female, the median age was 27 years (interquartile range, 22-36), 661 (19.1%) belonged to at least one key population and 2124 (61.4%) had never been tested for HIV; 3329 (99.8% of those who answered) reported being "very satisfied" or "satisfied" with the testing process. The proportions of test results interpreted as positive by self-testers among those interpreted as positive by HCWs were 95% for HIV-1/2 antibody, 95% for HBsAg and 78% for HCAb. These proportions were higher than those observed in a previous study evaluating another 3-in-1 RDT for HIV, HBsAg and HCAb, possibly due to the use of video instructions instead of paper-based instructions, lower prevalence and co-infection rates, or lower percentages of clients with low education level. Multiplex self-testing simplified and streamlined the service delivery process and was well accepted. HCW assistance proved to be essential in a limited number of cases.
