Zika Virus Infects Human Cortical Neural Progenitors and Attenuates Their Growth

ZIKV Strains' Different Phenotypes in Human Neural Cells Could be a Hint for the Emergence of the New Clinical Neurological Outcomes

Before it emerged as the suspected cause for the increased incidence of microcephaly observed in north-east Brazil in 2015, the vast majority of physicians were not familiar with Zika virus. But, that changed dramatically with the worldwide publicity given to this emerging public health threat. On February 1, 2016, the Director General of the World Health Organization (WHO) declared a Public Health Emergency of International Concern (PHEIC). This followed growing concerns about reports of Guillain-Barré syndrome appearing concomitantly with a Zika virus outbreak in French Polynesia from late 2013 to early 2014. Although Zika virus has not so far been proven to cause microcephaly or Guillain-Barré syndrome, scientific publications have started to emerge that have strengthened the aetiological connection between Zika virus and both maladies. The virus was first isolated in 1947 from a rhesus macaque captured in the Zika forest of Uganda from which it got its name 1. Zika virus is an arbovirus belonging to the Flaviviridae family and is transmitted by mosquitos. Unlike many pathogenic flaviviruses, like yellow fever virus, Japanese encephalitis virus, the four dengue viruses and West Nile virus, Zika virus had previously been considered to cause just a mild disease, with symptoms such as fever, rash, arthralgia, muscle pain and conjunctivitis 1, 2. In fact, more than 80% of those infected with Zika virus are asymptomatic. As Zika virus antibodies cross-react with dengue virus, the specific diagnosis of Zika virus infection relies on the detection of the virus nucleic acid in bodily fluids by reverse-transcriptase polymerase chain reaction or by detecting virus-specific immunoglobulin M antibodies. Until 2007, when an outbreak of the virus affected 70% of the population of the Micronesian islands of the Yap State, Zika virus had only been seen in Africa and South-East Asia. Six years later, a Zika virus epidemic occurred in French Polynesia, and it is estimated that more than 32 000 people were infected 3. The virus was probably introduced to the Americas in 2014, and the first report of autochthonous transmission in Brazil was as late as May 2015 1. Probably, the virus spread from Polynesia to the Americas by competitors from Pacific countries who took part in an international canoeing competition in Rio de Janeiro in August 2014 2. Zika virus has now spread to 31 countries and territories in the Americas, including Puerto Rico 4. The virus that infects human is carried by mosquitoes of the Aedes species, primarily by Aedes aegypti and probably also by Aedes albopictus 1. As the virus has been found in Puerto Rico, it is now considered to be only a matter of time before mosquito-born transmission of Zika virus will also be found in the United States. The virus can be found in urine and sperm and sexual transmission has been reported. Zika virus infections have also been found in patients in Europe and the United States who travelled to infected areas. Autochthonous transmission from such cases has been reported, probably due to sexual contact 4. As mentioned above, the reason for the recent public attention focused on Zika virus, and the PHEIC issued by the WHO, is its connection to Guillain-Barré syndrome and microcephaly. Guillain-Barré syndrome is an autoimmune postinfectious neurological disorder characterised by an ascending weakness starting in the distal legs 5, and in 20–30% of cases, it presents with rapid progressive paralysis and respiratory failure 5. The disease usually reaches its peak in two to 4 weeks, followed by a plateau phase of some months followed by a recovery phase. The mortality rate is 3–7%. It can be classified as an acute motor axonal neuropathy, where complement-fixing autoimmune antiganglioside antibodies attack nerve axon membranes, or an acute inflammatory demyelinating polyneuropathy. The former condition is usually the more serious 5. Guillain-Barré syndrome has been described after infections, particularly with campylobacter jejuni, but also with cytomegalovirus, Epstein–Barr virus, influenza A virus, hepatitis E virus, Mycoplasma pneumonia and Haemophilus influenzae 5. More recently, it has also been associated with arboviruses like chikungunia virus, West Nile virus, Japanese encephalitis virus and dengue virus 3. When the outbreak of Zika virus occurred in French Polynesia in 2013–2014, the diagnosis of Guillain-Barré syndrome increased from three to ten cases per year to 42 cases between November of 2013 and February of 2014 3, a 20-fold higher incidence than the previous four years 4. These 42 patients were affected by the acute motor axonal neuropathy type of the syndrome, with rapid progression but a short plateau phase that only lasted days. In an age- and sex-matched case-controlled study of these 42 patients, the risk of developing Guillain-Barré syndrome was calculated to be 0.24 per 1000 Zika virus infections 3. The study showed that 37 of the 42 patients had a history of viral syndrome for a median of six days prior to the onset of Guillain-Barré syndrome, and all of them (100%) had serological evidence of a recent Zika virus infection. This was compared with 54 (56%) of the 98 patients in the control group, who were recruited to the same hospital, but did not have febrile illness (p < 0.0001) 3. No other infection was diagnosed in the 42 patients, making it highly probable that Zika virus was the cause of Guillain-Barré syndrome in these patients. Although it has not yet been proven to be the causative agent, Zika virus infections have been reported to be linked to an increased incidence of Guillain-Barré syndrome in the state of Bahia in Brazil, Colombia, El Salvador, Suriname and Venezuela. In addition, cases of Guillain-Barré syndrome combined with Zika virus have been reported from Martinique, Puerto Rica and Panama 4. The other neurological disorder that has recently been linked to the Zika virus is microcephaly. During the four months from October 22, 2015 to February 27, 2016, no less than 5909 suspected cases of microcephaly were reported in Brazil, particularly in its northeast region, compared to a national average of 163 cases per year in the previous 15 years 4. Of these cases, 1687 have been investigated further and 641 (38%) were confirmed to fulfil the definition of microcephaly and/or central nervous system malformations associated with congenital infection 4, corresponding to at least a 40-fold increase in incidence. During the outbreak of Zika virus in French Polynesia, described above, 19 cases of congenital central nervous system malformations, including eight cases of microcephaly, were reported, compared to a national average of zero to two cases per year 4. Apart from associations with the timings and geographical locations of Zika virus outbreaks and these congenital central nervous system malformations, three reports published this year have identified Zika virus infection as the probable a cause of microcephaly 6, 7. In the first two reports, Zika virus ribonucleic acid was detected in the brain tissue, but not any other tissue, of a 32-week-old Slovenian foetus with microcephaly 6 and in a Finnish foetus with brain abnormalities terminated at 21 weeks of gestation 7. The two mothers had probably been infected in north-eastern Brazil and Central America, respectively, both at the end of the first trimester. Of note, ultrasonography may not show microcephaly at 20 weeks of gestation 6, 7. The third report was a study by Tang et al. 8 that showed that the Zika virus could infect and propagate in cultured cortical human neural progenitor cells derived from induced pluripotent stem cells, proving that the virus to be neurotropic. Unfortunately, there is probably little that can be done to halt the present Zika virus epidemic in the Americas. There is no antiviral intervention or vaccine available yet, which are both desperately needed, so are specific and easy to perform serological diagnostic tests for the detection of past Zika virus infection. All we can do at the moment is to try to control the mosquitos that carry the virus, discourage pregnant women from travelling to infected areas and raise awareness of the risk of transmission from sexual contact. In the meantime, readers may be interested in the frequently asked questions document on the Zika virus, which can be accessed from the home page of the Global Virus Network's website at: http://gvn.org/zika/.

Zika virus (ZIKV) infection attenuates the growth of human neural progenitor cells (hNPCs). As these hNPCs generate the cortical neurons during early brain development, the ZIKV-mediated growth retardation potentially contributes to the neurodevelopmental defects of the congenital Zika syndrome. Here, we investigate the mechanism by which ZIKV manipulates the cell cycle in hNPCs and the functional consequence of cell cycle perturbation on the replication of ZIKV and related flaviviruses. We demonstrate that ZIKV, but not dengue virus (DENV), induces DNA double-strand breaks (DSBs), triggering the DNA damage response through the ATM/Chk2 signaling pathway while suppressing the ATR/Chk1 signaling pathway. Furthermore, ZIKV infection impedes the progression of cells through S phase, thereby preventing the completion of host DNA replication. Recapitulation of the S-phase arrest state with inhibitors led to an increase in ZIKV replication, but not of West Nile virus or DENV. Our data identify ZIKV's ability to induce DSBs and suppress host DNA replication, which results in a cellular environment favorable for its replication.IMPORTANCE Clinically, Zika virus (ZIKV) infection can lead to developmental defects in the cortex of the fetal brain. How ZIKV triggers this event in developing neural cells is not well understood at a molecular level and likely requires many contributing factors. ZIKV efficiently infects human neural progenitor cells (hNPCs) and leads to growth arrest of these cells, which are critical for brain development. Here, we demonstrate that infection with ZIKV, but not dengue virus, disrupts the cell cycle of hNPCs by halting DNA replication during S phase and inducing DNA damage. We further show that ZIKV infection activates the ATM/Chk2 checkpoint but prevents the activation of another checkpoint, the ATR/Chk1 pathway. These results unravel an intriguing mechanism by which an RNA virus interrupts host DNA replication. Finally, by mimicking virus-induced S-phase arrest, we show that ZIKV manipulates the cell cycle to benefit viral replication.

The re-emergence of Zika virus (ZIKV) in the Western Hemisphere has resulted in global public health crisis since 2015. ZIKV preferentially infects and targets human neural progenitor cells (hNPCs) and causes fetal microcephaly upon maternal infection. hNPCs not only play critical roles during fetal brain development, but also persist in adult brain throughout life. Yet the mechanism of innate antiviral immunity in hNPCs remains largely unknown. Here, we show that ZIKV infection triggers the abundant production of virus-derived small interfering RNAs in hNPCs, but not in the more differentiated progenies or somatic cells. Ablation of key RNAi machinery components significantly enhances ZIKV replication in hNPCs. Furthermore, enoxacin, a broad-spectrum antibiotic that is known as an RNAi enhancer, exerts potent anti-ZIKV activity in hNPCs and other RNAi-competent cells. Strikingly, enoxacin treatment completely prevents ZIKV infection and circumvents ZIKV-induced microcephalic phenotypes in brain organoid models that recapitulate human fetal brain development. Our findings highlight the physiological importance of RNAi-mediated antiviral immunity during the early stage of human brain development, uncovering a novel strategy to combat human congenital viral infections through enhancing RNAi.

Zika virus (ZIKV) is spread by mosquito bites and is unique among known flaviviruses for being able to cause microcephaly. Entry factors for ZIKV are incompletely understood, but phosphatidylserine (PS) receptors, including the TAM (Tyro3, AXL, and Mer) and TIM (T-cell Ig mucin) families, can serve as cofactors for flavivirus entry in a cell type-specific manner. We identify AXL as the top hit in a CRISPR/Cas9 genome-wide screen in human glioblastoma cells and establish a definitive role of AXL, but not TYRO3 or MerTK, for ZIKV infection. Additionally, Spondweni virus also shows AXL dependency, while dengue virus infection is not affected by AXL knockout. Passage of ZIKV in AXL knockout (KO) cells generated a mutant virus capable of infection via AXL-independent mechanisms, and multiple independent selections identified a common mutation, H83R, in the prM coding region of the ZIKV genome. The mutant virus exhibits an increased infectivity rate in AXL KO cells as compared to wild-type ZIKV and is dependent upon the single H83R mutation. The mutant virus' ability to infect cells in an AXL-independent manner is unrelated to interferon signaling antagonism but likely pertains to a change in virus maturation that leads to a structural disturbance of the ZIKV virion. Our study provides evidence for a potential mechanism linking the viral structural proteins and host PS receptor usage during flavivirus infection.IMPORTANCEA major challenge in elucidating the mechanism of Zika virus (ZIKV) pathogenesis is the multitude of cell types it infects with distinct requirements. The role of phosphatidylserine (PS) receptors in ZIKV infection is cell type-specific, and the controversy surrounds their function in flavivirus entry. Here, we establish a definitive requirement of AXL for infection of human glioblastoma cells by both Zika and Spondweni virus. We then identified a single amino acid mutation (H83R) in the prM protein of ZIKV that allowed AXL-independent infection of these cells. The H83R-mediated escape of AXL requirement is independent of interferon (IFN) signaling suppression by AXL; instead, the mutation has the potential to disrupt the virus assembly and virion structure. This study reveals a previously unknown connection between the PS receptor usage and the flavivirus prM gene, which can guide detailed molecular mechanism studies of the interplay between virion assembly and virus entry.

Zika virus (ZIKV) and Dengue virus (DENV) are mosquito-borne viruses of the Flavivirus genus that could cause congenital microcephaly and hemorrhage, respectively, in humans, and thus present a risk to global public health. A preventive vaccine against ZIKV remains unavailable, and no specific antiviral drugs against ZIKV and DENV are licensed. Medicinal plants may be a source of natural antiviral drugs which mostly target viral entry. In this study, we evaluate the antiviral activity of Doratoxylum apetalum, an indigenous medicinal plant from the Mascarene Islands, against ZIKV and DENV infection. Our data indicated that D. apetalum exhibited potent antiviral activity against a contemporary epidemic strain of ZIKV and clinical isolates of four DENV serotypes at non-cytotoxic concentrations in human cells. Time-of-drug-addition assays revealed that D. apetalum extract acts on ZIKV entry by preventing the internalisation of virus particles into the host cells. Our data suggest that D. apetalum-mediated ZIKV inhibition relates to virus particle inactivation. We suggest that D. apetalum could be a promising natural source for the development of potential antivirals against medically important flaviviruses.

Zika virus (ZIKV) infection can lead to severe congenital outcomes, yet the mechanisms governing its entry into host cells remain understood. ZIKV is a flavivirus known to exploit multiple cellular receptors and cofactors, particularly in neural cells, where infection can result in congenital Zika syndrome (CZS). Here we show that plasminogen activator inhibitor-1 (PAI-1), a serine protease inhibitor involved in hemostasis, directly interacts with ZIKV particles and critically enhances viral replication in diverse cell types, including human neural progenitor cells and three-dimensional neural organoids. Our findings reveal that PAI-1 may contribute to ZIKV infection through distinct or complementary pathways, underscoring the virus’s versatile entry mechanisms. Inhibition of PAI-1 via tiplaxtinin (TPX) dramatically reduces viral load and impedes infectious particle release, demonstrating a dose-dependent effect that is especially potent in neural models relevant to CZS. These results highlight PAI-1 as an essential mediator of ZIKV pathogenesis and suggest that targeting PAI-1 function could represent a novel therapeutic avenue. Given the risk of future ZIKV outbreaks and the devastating impact of CZS, interventions aimed at PAI-1 may hold promise for reducing the global burden of ZIKV infection.

Background The molecular mechanisms underpinning the neurologic and congenital pathologies caused by Zika virus (ZIKV) infection remain poorly understood. It is also unclear why congenital ZIKV disease was not reported prior to the recent epidemics in French Polynesia and the Americas, despite evidence that Zika virus has actively circulated in parts of Africa and Asia since 1947 and 1966, respectively. Methods Due to advances in the stem cell-based technologies, we can now model ZIKV infections of the central nervous system in human stem cell-derived neural progenitor cells and cerebral organoids, which recapitulate complex 3-dimensional neural architecture. We apply Seq-Well — a simple, portable platform for massively parallel single-cell RNA sequencing — to characterize these neural models infected with ZIKV. We detect and quantify host mRNA transcripts and viral RNA with single-cell resolution, thereby defining transcriptional features of both uninfected and infected cells. Results Although flavivirus RNAs lack a poly(A) tail, we present evidence that viral RNAs are specifically primed for reverse transcription at internal runs of adenosines, and that sequencing reads cover the entire non-polyadenylated viral genome. In neural progenitor cells, single cell sequencing reveals that while uninfected bystander cells strongly upregulate interferon pathway genes, these pathways are largely suppressed in cells infected with ZIKV within the same culture dish. Single cell sequencing identifies multiple cell types in our cerebral organoids including neural progenitor cells, intermediate progenitor cells, and neurons of varied maturity. Using this model, we find that neurons, not typically considered targets of ZIKV in the developing brain, contain high copy numbers of ZIKV genomes. It remains uncertain whether neurons are directly infected, or if infected neural progenitor cells differentiate into neurons, carrying virus with them. Notably, the neuronal bystander cell population shows limited interferon gene pathway upregulation compared to neural progenitors. Conclusions Overall, our work provides insight into the pathogenesis of ZIKV associated microcephaly, identifies potential new tropisms of ZIKV in the human brain, and suggests that both virus replication and host response mechanisms underlie the neuropathology of ZIKV infection.

The Zika virus (ZIKV) is teratogenic and considered a TORCH pathogen (toxoplasmosis [Toxoplasma gondii], rubella, cytomegalovirus, herpes simplex virus [HSV], and other microorganisms capable of crossing the blood-placenta barrier). In contrast, the related flavivirus dengue virus (DENV) and the attenuated yellow fever virus vaccine strain (YFV-17D) are not. Understanding the mechanisms used by ZIKV to cross the placenta is necessary. In this work, parallel infections with ZIKV of African and Asian lineages, DENV, and YFV-17D were compared for kinetics and growth efficiency, activation of mTOR pathways, and cytokine secretion profile using cytotrophoblast-derived HTR8 cells and monocytic U937 cells differentiated to M2 macrophages. In HTR8 cells, ZIKV replication, especially the African strain, was significantly more efficient and faster than DENV or YFV-17D. In macrophages, ZIKV replication was also more efficient, although differences between strains were reduced. Greater activation of the mTORC1 and mTORC2 pathways in HTR8 cells infected with ZIKV than with DENV or YFV-17D was observed. HTR8 cells treated with mTOR inhibitors showed a 20-fold reduction in ZIKV yield, versus 5- and 3.5-fold reductions for DENV and YFV-17D, respectively. Finally, infection with ZIKV, but not DENV or YFV-17D, efficiently inhibited the interferon (IFN) and chemoattractant responses in both cell lines. These results suggest a gating role for the cytotrophoblast cells in favoring entry of ZIKV, but not DENV and YFV-17D, into the placental stroma. IMPORTANCE Zika virus acquisition during pregnancy is associated with severe fetal damage. The Zika virus is related to dengue virus and yellow fever virus, yet fetal damage has not been related to dengue or inadvertent vaccination for yellow fever during pregnancy. Mechanisms used by the Zika virus to cross the placenta need to be deciphered. By comparing parallel infections of Zika virus strains belonging to the African and Asian lineages, dengue virus, and the yellow fever vaccine virus strain YFV-17D in placenta-derived cytotrophoblast cells and differentiated macrophages, evidence was found that Zika virus infections, especially by the African strains, were more efficient in cytotrophoblast cells than dengue virus or yellow fever vaccine virus strain infections. Meanwhile, no significant differences were observed in macrophages. Robust activation of the mTOR signaling pathways and inhibition of the IFN and chemoattractant response appear to be related to the better growth capacity of the Zika viruses in the cytotrophoblast-derived cells.

Since the emergence of Zika virus (ZIKV), reports of microcephaly have increased considerably in Brazil; however, causality between the viral epidemic and malformations in fetal brains needs further confirmation. We examined the effects of ZIKV infection in human neural stem cells growing as neurospheres and brain organoids. Using immunocytochemistry and electron microscopy, we showed that ZIKV targets human brain cells, reducing their viability and growth as neurospheres and brain organoids. These results suggest that ZIKV abrogates neurogenesis during human brain development.

Since the emergence of Zika virus (ZIKV), reports of microcephaly have increased dramatically in Brazil; however, causality between the widespread epidemic and malformations in fetal brains has not been confirmed. Here, we examine the effects of ZIKV infection in human neural stem cells growing as neurospheres and cerebral organoids. Using immunocytochemistry and electron microscopy, we show that ZIKV targets human brain cells, reducing their viability and growth as neurospheres and cerebral organoids. These results suggest that ZIKV abrogates neurogenesis during human brain development.

The Zika Virus (ZIKV) is an emerging RNA virus that cause congenital birth defects and neurological compilations among infected individuals. Since the 2015 ZIKV outbreak in Brazil, the Centers for Disease Control, and Prevention (CDC) reports over 35,000 cases ZIKV disease cases within the United States (US) and US territories. Although ZIKV is primarily transmitted through an infected Aedes mosquito, recent studies demonstrate this pathogenic virus can be transmitted via sexual contact with an infected partner. CDC confirmed multiple clinical cases of infected patients acquired ZIKV through sexual transmission within the US. Additionally, mounting evidence from animal and cell studies demonstrate that the female reproductive tract supports ZIKV replication following intravaginal exposure. Despite the growing evidence associating ZIKV to sexual transmission, the underlying molecular mechanism involving vaginal transmission remains elusive. The overarching goal is to examine the role of the vaginal tract in ZIKV sexual transmission on a molecular level. The vaginal tract has multiple layers of epithelial cells that constitutes as the first line of defense against foreign pathogens. Given the capacity of sexual intercourse, we hypothesize that the initial event for ZIKV vaginal transmission is most likely through direct viral uptake at the outermost epithelial layer of the vaginal tract. We aim to test our hypothesis by (1) characterizing the replication kinetics of ZIKV in human vaginal epithelial cells (hVECs) in vitro and (2) determining the functional role of the putative ZIKV entry receptor, AXL, in hVECs. Our recent findings indicate hVECs is a permissive cell target for local ZIKV replication and production. Vaginal infection resulted in de novo replication of the ZIKV RNA genome, active production of the viral envelope protein, and steady release of infectious viral particles. Cell viability studies further indicate that hVECs do not exhibit significant cytopathic effect following ZIKV exposure. Additional studies show that the flaviviral entry receptor AXL is endogenously expressed in hVECs on a protein, mRNA level, and surface level. When expression patterns were compared between Vero and 293T cell lines, our results show similar protein levels of endogenous AXL in both Vero and VK2E6E7 cell lines, which may suggest that ZIKV entry via AXL‐mediated pathway and the dynamics of viral growth act independently of one another during sexual transmission. Our AXL knockdown and overexpression studies validate that this tyrosine receptor kinase is involved in ZIKV vaginal entry. In the future, kinase inhibitory studies will be performed to further validate whether downstream signaling contributes to ZIKV replication and production in hVECs. The outcome of this research will provide further insight into host‐virus interactions on a molecular level, which can lead to devising therapeutic agents aimed at interfering with the pathology caused by the virus.Support or Funding Information• T32 Grant: NIH National Heart, Lung, and Blood Institute, Research Training in Cardiovascular Biology at Meharry

The latest outbreak of Zika virus (ZIKV) in the Americas was associated with significant neurologic complications, including microcephaly of newborns. We evaluated mechanisms that regulate ZIKV entry into human fetal astrocytes (HFAs). Astrocytes are key players in maintaining brain homeostasis. We show that the central mediator of canonical Wnt signaling, β-catenin, regulates Axl, a receptor for ZIKV infection of HFAs, at the transcriptional level. In turn, ZIKV inhibited β-catenin, potentially as a mechanism to overcome its restriction of ZIKV internalization through regulation of Axl. This was evident with three ZIKV strains tested but not with a laboratory-adapted strain which has a large deletion in its envelope gene. Finally, we show that β-catenin-mediated Axl-dependent internalization of ZIKV may be of increased importance for brain cells, as it regulated ZIKV infection of astrocytes and human brain microvascular cells but not kidney epithelial (Vero) cells. Collectively, our studies reveal a role for β-catenin in ZIKV infection and highlight a dynamic interplay between ZIKV and β-catenin to modulate ZIKV entry into susceptible target cells. IMPORTANCE ZIKV is an emerging pathogen with sporadic outbreaks throughout the world. The most recent outbreak in North America was associated with small brains (microcephaly) in newborns. We studied the mechanism(s) that may regulate ZIKV entry into astrocytes. Astrocytes are a critical resident brain cell population with diverse functions that maintain brain homeostasis, including neurogenesis and neuronal survival. We show that three ZIKV strains (and not a heavily laboratory-adapted strain with a large deletion in its envelope gene) require Axl for internalization. Most importantly, we show that β-catenin, the central mediator of canonical Wnt signaling, negatively regulates Axl at the transcriptional level to prevent ZIKV internalization into human fetal astrocytes. To overcome this restriction, ZIKV downregulates β-catenin to facilitate Axl expression. This highlights a dynamic host-virus interaction whereby ZIKV inhibits β-catenin to promote its internalization into human fetal astrocytes through the induction of Axl.

Zika virus (ZIKV) has emerged as a serious health threat in the Americas and the Caribbean. ZIKV is transmitted by the bite of an infected mosquito, sexual contact, and blood transfusion. ZIKV can also be transmitted to the developing fetus in utero, in some cases resulting in spontaneous abortion, fetal brain abnormalities, and microcephaly. In adults, ZIKV infection has been correlated with Guillain–Barre syndrome. Despite the public health threat posed by ZIKV, neither a vaccine nor antiviral drugs for use in humans are currently available. We have identified an amphibian host defense peptide, Yodha, which has potent virucidal activity against ZIKV. It acts directly on the virus and destroys Zika virus particles within 5 min of exposure. The Yodha peptide was effective against the Asian, African, and South American Zika virus strains and has the potential to be developed as an antiviral therapeutic in the fight against Zika virus. The peptide was also effective against all four dengue virus serotypes. Thus, Yodha peptide could potentially be developed as a pan-therapeutic for Zika and dengue viruses.

Brain-Region-Specific Organoids Using Mini-bioreactors for Modeling ZIKV Exposure