14 Perspectives of Aptamers for Medical Applications
415
Viral diagnosis assay is pivotal to detect viral agents as early as possible to guide
the treatment and take precautions. A range of virus-specific aptamers were generated
against many viruses.
For example, aptamers that diagnose HIV proteins such as Tat, Rev, CD4 have
been primarily used in several biosensor systems and hold great significance as
diagnostic tool development for HIV. Tat is an immediate early gene of HIV and its
expression is suppressed by antiretrovirals. Its protein transduction domain allows
secretion by infected cells and uptake by bystander cells where it mediates pleiotropic
effects, leading to several HIV-associated comorbidities in the cART era. Hence
determining amounts of Tatas a biomarker in the serum for subclinical HIV-associated
comorbidities before the manifestation of clinical disease can be useful. Several
aptamer-based biosensors have been designed for the detection of HIV-1 Tat protein,
accompany with different detection methods SPR [39], quartz crystal microbalance
(QCM) [39], and Diamond field-effect transistor (FET) [40]. Anti-Rev aptamers
have also been used in several biosensor systems using methods such as based in
SPR, QCM, and GHz impedance biosensor system [41]. HIV specifically targets
CD4 cells, Blocking CD4 using monoclonal antibodies results in inhibition of viral
entry [42]. Davis et al. [43] used modified RNA aptamers for flow cytometry of cellsurface human CD4. Fluorophore conjugated aptamers were developed for diagnostic
applications as well. Zhou et al. [44] generated thiolated anti-CD4 RNA aptamers
to capture the cells expressing CD4 antigen, which is comparable to the capture
efficiency for the CD4 antibody. These aptamers hold promise in progression in
diagnosis and the generation of aptamer-based monitoring and diagnostic kits for
HIV/AIDS.
Human papillomavirus (HPV) is another common group of viruses that infect
humans. Most humans feel nothing after infection, but some types of HPV can cause
genital warts or cancer which will arouse panic in infected persons. The HPV vaccine
protects against HPV. A reliable well-designed potency assay can be used to ensure
efficacy, monitor product stability, and confirm batch-to-batch consistency of the
HPV vaccine. To test the feasibility of using aptamers as an alternative to traditional
antibody reagents in a vaccine potency assay, Trausch et al. [45] selected an aptamer
against the HPV Type 16 virus-like-particle, named HPV-07. Compared to a traditional ELISA the aptamer-based ELISA displays a higher precision (intermediate
precision of 6.3%) and a large linear range spanning from 25 to 200%. This assay
format significantly reduces time and resource consumptions.
To date no viral pathogen diagnosis is developed rapidly in POCTs, as exemplified
by the case in the detection of Tuberculosis (TB). Tuberculosis is a life-threatening
disease caused by Mycobacterium tuberculosis (Mtb), which is mainly transmitted
by aerosols released from the upper respiratory tract of an infected person to a healthy
one. According to the WHO 2019 global TB report [46], About 7 million people were
reported to have been furnished with quality TB care in 2018. Besides, TB-related
deaths dropped from 1.6 million in 2017 to 1.5 million in 2018. However, TB remains
the top infectious killer worldwide, with 10 million people falling ill with TB in 2018.
415
Viral diagnosis assay is pivotal to detect viral agents as early as possible to guide
the treatment and take precautions. A range of virus-specific aptamers were generated
against many viruses.
For example, aptamers that diagnose HIV proteins such as Tat, Rev, CD4 have
been primarily used in several biosensor systems and hold great significance as
diagnostic tool development for HIV. Tat is an immediate early gene of HIV and its
expression is suppressed by antiretrovirals. Its protein transduction domain allows
secretion by infected cells and uptake by bystander cells where it mediates pleiotropic
effects, leading to several HIV-associated comorbidities in the cART era. Hence
determining amounts of Tatas a biomarker in the serum for subclinical HIV-associated
comorbidities before the manifestation of clinical disease can be useful. Several
aptamer-based biosensors have been designed for the detection of HIV-1 Tat protein,
accompany with different detection methods SPR [39], quartz crystal microbalance
(QCM) [39], and Diamond field-effect transistor (FET) [40]. Anti-Rev aptamers
have also been used in several biosensor systems using methods such as based in
SPR, QCM, and GHz impedance biosensor system [41]. HIV specifically targets
CD4 cells, Blocking CD4 using monoclonal antibodies results in inhibition of viral
entry [42]. Davis et al. [43] used modified RNA aptamers for flow cytometry of cellsurface human CD4. Fluorophore conjugated aptamers were developed for diagnostic
applications as well. Zhou et al. [44] generated thiolated anti-CD4 RNA aptamers
to capture the cells expressing CD4 antigen, which is comparable to the capture
efficiency for the CD4 antibody. These aptamers hold promise in progression in
diagnosis and the generation of aptamer-based monitoring and diagnostic kits for
HIV/AIDS.
Human papillomavirus (HPV) is another common group of viruses that infect
humans. Most humans feel nothing after infection, but some types of HPV can cause
genital warts or cancer which will arouse panic in infected persons. The HPV vaccine
protects against HPV. A reliable well-designed potency assay can be used to ensure
efficacy, monitor product stability, and confirm batch-to-batch consistency of the
HPV vaccine. To test the feasibility of using aptamers as an alternative to traditional
antibody reagents in a vaccine potency assay, Trausch et al. [45] selected an aptamer
against the HPV Type 16 virus-like-particle, named HPV-07. Compared to a traditional ELISA the aptamer-based ELISA displays a higher precision (intermediate
precision of 6.3%) and a large linear range spanning from 25 to 200%. This assay
format significantly reduces time and resource consumptions.
To date no viral pathogen diagnosis is developed rapidly in POCTs, as exemplified
by the case in the detection of Tuberculosis (TB). Tuberculosis is a life-threatening
disease caused by Mycobacterium tuberculosis (Mtb), which is mainly transmitted
by aerosols released from the upper respiratory tract of an infected person to a healthy
one. According to the WHO 2019 global TB report [46], About 7 million people were
reported to have been furnished with quality TB care in 2018. Besides, TB-related
deaths dropped from 1.6 million in 2017 to 1.5 million in 2018. However, TB remains
the top infectious killer worldwide, with 10 million people falling ill with TB in 2018.