This study examined the ability of Zika virus to infect and lyse human neuroblastoma cells, which could have potential as an oncolytic therapy. The study found that various neuroblastoma cell lines were permissive to Zika virus infection, showing cytopathic effects and viral replication. However, one cell line, SK-N-AS, did not express the CD24 receptor and was resistant to significant infection. Knocking down CD24 in another cell line prevented expression of the NS1 viral protein and limited infection. The results suggest CD24 plays a role in Zika virus host cell specificity and could be a therapeutic target, with the virus showing potential as an oncolytic treatment for cancers expressing CD

1. ZIKA VIRUS AS AN ONCOLYTIC
TREATMENT OF HUMAN
NEUROBLASTOMA CELLS
REQUIRES CD24
JOSEPH MAZAR et al (2018)
PLOS ONE
UMAIMA SAAD
H1921141
MIC-641

2. NEUROBLASTOMA
• CANCER OF IMMATURE
NEUROBLASTS.
• MOST COMMON CHILDHOOD
TUMORS.
• POOR SURVIVAL RATE.
• AFFESTS NEUROBLASTS IN ADRENAL
GLANDS.
INTRODUCTION:

3. TREATMENT
• THERE IS A NEED FOR NEW
THERAPIES FOR NEUROBLASTOMA
DUE TO ITS HIGH DEATH RATE.
• IN BEGINNING OF 20TH CENTURY,
VIRUSES WERE SUGGESTED AS A
TREATMENT OF CANCER.

4. WHAT IS ZIKA VIRUS ?
• NEUROTROPIC MEMBER OF
FLAVIVIRUSES.
• MOSQUITO-BORNE PATHOGEN.
• CAUSES NERVOUS SYSTEM
COMPLICATIONS.
• BIRTH DEFECTS.
• MICROCEPHALY AND SEVERE BRAIN
DEFECTS.

5. AIM AND PURPOSE OF STUDY:
IN THIS STUDY THEY AIMED TO SHOW THAT NEUROBLATOMA CELLS
WIDELY ALLOW THE INFECTION OF ZIKA VIRUS.
SHOWING EXTENSIVE CYTOPATHIC EFFECTS AND HIGH VIRAL TITRES.

6. BENEFITS OF ZIKA VIRUSES
• CAUSES LYSIS IN
NEUROBLASTIC CELLS.
• AS AN OCOLYTIC THERAPY FOR
HUMANS.
• LESS TOXICITY, THAN OTHER
TOXIC TREATMENTS.
• ZIKA VIRUS PROVIDE
TARGETED TREATMENT.

7. MATERIALS AND METHODS :
• CELL LINES AND VIRUS (ZIKA VIRUS STRAIN PRVABC59).
• CELL VIABILITY ASSAYS
• WESTERN BLOT ANALYSIS
• VIRAL TITRE ASSAYS
• IMMUNOCYTOCHEMISTRY
• QUANTIATIVE REVERSE TRANSCRIPTASE PCR

8. ARRAY OF NEUROBLASTOMA ARE PERMISSIVE OF ZIKA VIRUS
DIFFERENT CULTURED NEUROBLASTOMA CELS WERE
INFECTED WITH ZIKA VIRUSES AT MOI = 10
1. IMR-32
2. SMS-KAN
3. SK-N-Be(1)
4. SK-N-AS
5. LA-N-6
6. CHLA-42
AND VERO CELLS

9. RESULTS

10. CELL VIABILITY TIME COURSE OF NEUROBLASTOMA CELLS INFECTED BY ZIKA VIRUS
PRVABC59

11. WESTERN BLOTTTING
IMMUNOFLOURESCENCE

12. ZIKA VIRUS INFECTION CORELATS WITH CD24
EXRESSION IN NEUROBLASTOMA CELLS
• THE TRANSCRIPTS THAT ENCODES CELL MEMBRANE ASSOCIATED PROTEINS
WERE IDENTIFIED IN ALL CELL WHICH WERE POORLY EXPRESSED IN SK-N-AS
CELLS.
• CD24 RECEPTORS WERE FOUND IN ALL NEUROBLASTOMA CELL LINES
EXCEPT IN SK-N-AS CELLS IN WHCH NO CD24 PROTIEN WAS DETECTABLE.
• INTECTIONS IN SK-N-AS CELLS INDUCED ONLY LIMITED CYTOPETHIC
EFFECTS.

13. ANALYSIS OF CD24 TRANSCRIPTS:
• CD24 TRANSCRIPTS REVEALED THREE SEPARATE TRANSCRIPTS WHICH
WERE HIGHLY EXPRESSED IN IMR-32 THAN SK-N-AS CELLS.
• DIFFERING IN THEIR OPEN READING FRAMES.
• TWO VARIANTS OF CD24: VARIANT-001 AND VARIANT-007
• QUANTITATIVE REAL-TIME PCR (qRT-PCR) WAS PERFORMED.
• OBSERVED THAT BOTH VARIANTS WERE EXPRESSED IN ALL CELLS
EXCEPT IN SK-N-AS CELLS

14. ANALYSIS OF CD24 EXPRESSION IN HUMAN NEUROBLASTOMA CELLS

15. NECESSITY OF CD24 RECEPTORS FOR ZIKA VIRUS:
TO DETERMINE IF CD24 HAD ANY RELEVANCE TO ZIKA INFECTION,
PERMISSIVE IMR-32 CELLS WERE TRANSFECTED WITH A SHORT
INTERFERING RNA (siRNA) DESIGNED TO DISRUPT EXPRESSION OF ALL
CD24 VARIANT TRANSCRIPTS.
THE RESULTS INDICATED THAT THE PRESENCE OF ENVELOPE PROTEIN
WAS LARGELY UNCHANGED AFTER KNOCK-DOWN OF CD24;
HOWEVER, THE PRODUCTION OF NS1 PROTEIN COMPLETELY
DISAPPEARED.

16. ANALYSIS OF ROLE OF CD24

17. ZIKA VIRUS DEVASTATING IN INFANTS AND
CHILDREN
• CD24 RECEPTORS ARE EXPRESSED AT HIGHER LEVELS ON
METABOLICALLY ACTIVE AND PROGENITOR CELLS.
• THIS EXPLAINS THAT WHY ZIKA VIRUS INFECTIONS ARE MORE
DEVASTATING IN CHILDREN THAN IN ADULTS.
DISCUSSION:

18. ZIKA VIRUS AS A TREATMENT
• CD24 ACTS A MARKER FOR LIVER CANCER AS WELL.
• CD24 FREQUENTLY EXPRESSED ON HUMAN TUMOR
CELLS BUT NOT EXPRESSED ON MOST DIFFERENTIATED
CELLS .
• SUGGESTED THAT ZIKA VIRUS CAN BE USED AS A
THERAPY IN INDIVIDUALS WITH CD4+ TUMORS
RESULTING IN SELECTIVITY OF INFECTION.

19. CONCLUSION:
• THESE RESULTS SUGGEST A POSSIBLE ROLE FOR CD24 IN HOST CELL SPECIFICITY
BY ZIKA VIRUS AND OFFER A POTENTIAL THERAPEUTIC TARGET FOR ITS
TREATMENT.
• OUR FINDINGS INDICATE THAT NEUROBLASTOMA CELLS ARE PERMISSIVE TO ZIKA
VIRUS INFECTION, AND CYTOPATHIC EFFECTS ARE INDUCED BY THIS INFECTION.
• FURTHERMORE, THIS DATA RAISE THE PROSPECT THAT ZIKA VIRUSES MAY BE
USEFUL FOR THE ONCOLYTIC THERAPY OF OTHER TUMORS.

20. LIMITATIONS OF THIS STUDY:
ACCORDING TO MY POINT OF VIEW THIS ARTICLE SHOULD HAVE
MENTIONED THAT
• WHY SK-N-AS CELLS ARE UNABLE TO EXPRESS CD24 ?
• WHAT IS THE ROLE OF CD24 WITH THE EXPRESSION OF NS1
PROTEINS ?
• IF VIRAL PARTICLE IS ABLE TO ATTACH TO THE CELLS WHY ITS UNABLE
TO REPLICATE AND LYSE THE CELS?

21. THANK YOU!