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  1. Artikel: Simultaneous co-circulation of two genotypes of dengue virus serotype 3 causing a large outbreak in Sri Lanka in year 2023.

    Ariyaratne, Dinuka / Senadheera, Bhagya / Kuruppu, Heshan / Jayadas, Tibutius Thanesh Pramanayagam / Gomes, Laksiri / Ranasinghe, Diyanath / Bary, Farha / Wijewickrama, Ananda / Márquez Aguilar, Sully / Bennett, Shannon / Jeewandara, Chandima / Malavige, Gathsaurie Neelika

    medRxiv : the preprint server for health sciences

    2024  

    Abstract: As many other countries, Sri Lanka experienced a marked rise in the number of dengue cases in 2023, with an unusual pattern of disease epidemiology. This rise coincided with the emergence of dengue virus (DENV) serotype 3 in Sri Lanka as the predominant ... ...

    Abstract As many other countries, Sri Lanka experienced a marked rise in the number of dengue cases in 2023, with an unusual pattern of disease epidemiology. This rise coincided with the emergence of dengue virus (DENV) serotype 3 in Sri Lanka as the predominant serotype after 2009. Interestingly, a discrepancy between NS1 rapid antigen test positivity and quantitative real time PCR positivity was observed, with 50% of NS1 positive samples being negative by molecular diagnostics. Following sequencing of the DENV-3 strains in 2023, we identified two DENV-3 genotypes (I and III) co-circulating. While DENV-3 genotype III was detected by the modified CDC DENV-3 primers, genotype I evaded detection due to key mutations at forward and reverse primer binding sites. The co-circulation of multiple genotypes associated with an increase in cases highlights the importance of continuous surveillance of DENVs to identify mutations resulting in non-detection by diagnostics and differences in virulence.
    Sprache Englisch
    Erscheinungsdatum 2024-05-09
    Erscheinungsland United States
    Dokumenttyp Preprint
    DOI 10.1101/2024.05.09.24307112
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  2. Artikel: Identification of differences in the magnitude and specificity of SARS-CoV-2 nucleocapsid antibody responses in naturally infected and vaccinated individuals.

    Pushpakumara, Pradeep D / Jeewandara, Chandima / Bary, Farha / Madushanka, Deshan / Perera, Lahiru / Aberathna, Inoka Sepali / Nimasha, Thashmi / Jayamali, Jeewantha / Ranasinghe, Thushali / Kuruppu, Heshan / Danasekara, Saubhagya / Wijewickrama, Ananda / Ogg, Graham S / Malavige, Gathsaurie Neelika

    medRxiv : the preprint server for health sciences

    2023  

    Abstract: Background: As there are limited data on B cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan ... ...

    Abstract Background: As there are limited data on B cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan strain (WT), delta, omicron and in those who received the Sinopharm vaccines, which is an inactivated, whole virus vaccine.
    Methods: Using overlapping peptides representing the N protein, with an in-house ELISA, we mapped the immunodominant regions within the N protein, in seronegative (n=30), WT infected (n=30), delta infected (n=30), omicron infected+vaccinated (n=20) and Sinopharm (BBIBP-CorV) vaccinees (n=30). We then investigated the sensitivity and specificity of these immunodominant regions and analysed their conservation with other SARS-CoV-2 variants of concern, seasonal human coronaviruses and bat Sarbecoviruses. We then investigated the kinetics of responses to these regions in those with varying severity of acute COVID-19.
    Results: We identified four immunodominant regions aa 29-52, aa 155-178, aa 274 to 297 and aa 365 to 388, were highly conserved within SARS-CoV-2 and the bat coronaviruses. The magnitude of responses to these regions varied based on the infecting SARS-CoV-2 variants, with WT infected individuals predominantly recognizing aa155 to 178 regions, delta infected individuals and vaccinated+omicron infected individuals predominantly recognizing regions aa 29 to 52 and aa 274 to 294 regions. Sinopharm vaccinees recognized all four regions, with the magnitude of responses significantly lower than other groups. >80% of individuals gave responses above the positive cut-off threshold to many of the four regions, with some differences with individuals who were infected with different VoCs. These regions were found to be 100% specific, as none of the seronegative individuals gave any responses.
    Conclusions: N-protein specific responses appear to be detectable in over 90% of those who were naturally infected or vaccinated with a whole virus inactivated vaccine, with responses mainly directed against four regions of the protein, which were highly conserved. As these regions were highly specific with high sensitivity, they have a potential to be used to develop diagnostic assays and to be used in development of vaccines.
    Sprache Englisch
    Erscheinungsdatum 2023-01-07
    Erscheinungsland United States
    Dokumenttyp Preprint
    DOI 10.1101/2023.01.05.23284247
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Identification of differences in the magnitude and specificity of SARS-CoV-2 nucleocapsid antibody responses in naturally infected and vaccinated individuals.

    Pushpakumara, Pradeep Darshana / Jeewandara, Chandima / Bary, Farha / Madushanka, Deshan / Perera, Lahiru / Aberathna, Inoka Sepali / Nimasha, Thashmi / Jayamali, Jeewantha / Ranasinghe, Thushali / Kuruppu, Heshan / Danasekara, Saubhagya / Wijewickrama, Ananda / Ogg, Graham S / Malavige, Gathsaurie Neelika

    Clinical and experimental immunology

    2023  Band 215, Heft 3, Seite(n) 268–278

    Abstract: As there are limited data on B-cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan strain (WT), ... ...

    Abstract As there are limited data on B-cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan strain (WT), delta, omicron, and in those who received the Sinopharm vaccines, which is an inactivated, whole virus vaccine. Using overlapping peptides representing the N protein, with an in-house ELISA, we mapped the immunodominant regions within the N protein, in seronegative (n = 30), WT infected (n = 30), delta infected (n = 30), omicron infected + vaccinated (n = 20) and Sinopharm (BBIBP-CorV) vaccinees (n = 30). We then investigated the sensitivity and specificity of these immunodominant regions and analyzed their conservation with other SARS-CoV-2 variants of concern, seasonal human coronaviruses, and bat Sarbecoviruses. We identified four immunodominant regions aa 29-52, aa 155-178, aa 274-297, and aa 365-388, which were highly conserved within SARS-CoV-2 and the bat coronaviruses. The magnitude of responses to these regions varied based on the infecting SARS-CoV-2 variants, >80% of individuals gave responses above the positive cut-off threshold to many of the four regions, with some differences with individuals who were infected with different VoCs. These regions were found to be 100% specific, as none of the seronegative individuals gave any responses. As these regions were highly specific with high sensitivity, they have a potential to be used to develop diagnostic assays and to be used in development of vaccines.
    Mesh-Begriff(e) Humans ; Animals ; SARS-CoV-2 ; Antibody Formation ; Chiroptera ; Immunodominant Epitopes ; COVID-19 ; Nucleocapsid ; Antibodies, Viral
    Chemische Substanzen Immunodominant Epitopes ; Antibodies, Viral
    Sprache Englisch
    Erscheinungsdatum 2023-06-12
    Erscheinungsland England
    Dokumenttyp Journal Article
    ZDB-ID 218531-3
    ISSN 1365-2249 ; 0009-9104 ; 0964-2536
    ISSN (online) 1365-2249
    ISSN 0009-9104 ; 0964-2536
    DOI 10.1093/cei/uxad066
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Antibody and memory B cell responses to the dengue virus NS1 antigen in individuals with varying severity of past infection.

    Ramu, Shyrar Tanussiya / Dissanayake, Madushika / Jeewandara, Chandima / Bary, Farha / Harvie, Michael / Gomes, Laksiri / Wijesinghe, Ayesha / Ariyaratne, Dinuka / Ogg, Graham S / Malavige, Gathsaurie Neelika

    Immunology

    2023  Band 170, Heft 1, Seite(n) 47–59

    Abstract: To further understand the role of NS1-specific antibodies (Abs) in disease pathogenesis, we compared neutralizing antibody levels (Nabs), NS1-Ab levels, IgG antibody subclass profiles and NS1-specific memory B-cell responses (Bmems) in individuals, with ... ...

    Abstract To further understand the role of NS1-specific antibodies (Abs) in disease pathogenesis, we compared neutralizing antibody levels (Nabs), NS1-Ab levels, IgG antibody subclass profiles and NS1-specific memory B-cell responses (Bmems) in individuals, with varying severity of past dengue. Nabs (Neut50 titres) were assessed using the Foci Reduction Neutralization Test (FRNT) and in-house ELISAs were used to assess NS1-Abs and NS1-Ab subclasses for all four DENV serotypes in individuals with past DF (n = 22), those with past DHF (n = 14) and seronegative (SN) individuals (n = 7). B-cell ELISpot assays were used to assess NS1-specific Bmem responses. 15/22 (68.18%) individuals with past DF and 9/14 (64.29%) individuals with past DHF had heterotypic infections. Neut50 titres were found to be significantly higher for DENV1 than DENV2 (p = 0.0006) and DENV4 (p = 0.0127), in those with past DHF, whereas there was no significant difference seen in titres for different DENV serotypes in those with past DF. Overall NS1-Ab to all serotypes and NS1-specific IgG1 responses for DENV1, 2 and 4 serotypes were significantly higher in those with past DHF than individuals with past DF. Those with past DHF also had higher IgG1 than IgG3 for DENV1 and DENV3, whereas no differences were seen in those with past DF. Over 50% of those with past DF or DHF had NS1-specific Bmem responses to >2 DENV serotypes. There was no difference in the frequency of Bmem responses to any of the DENV serotypes between individuals with past DF and DHF. Although the frequency of Bmem responses to DENV1 correlated with DENV1-specific NS1-Abs levels (Spearman r = 0.35, p = 0.02), there was no correlation with other DENV serotypes. We found that those with past DF had broadly cross-reactive Nabs, while those with past DHF had higher NS1-Ab responses possibly with a different functionality profile than those with past DF. Therefore, it would be important to further evaluate the functionality of NS1-specific antibody and Bmem responses to find out the type of antibody repertoire that is associated with protection against severe disease.
    Mesh-Begriff(e) Humans ; Dengue Virus ; Dengue ; Antibodies, Viral ; Memory B Cells ; Antibodies, Neutralizing ; Immunoglobulin G ; Broadly Neutralizing Antibodies
    Chemische Substanzen Antibodies, Viral ; Antibodies, Neutralizing ; Immunoglobulin G ; Broadly Neutralizing Antibodies
    Sprache Englisch
    Erscheinungsdatum 2023-04-19
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 80124-0
    ISSN 1365-2567 ; 0019-2805 ; 0953-4954
    ISSN (online) 1365-2567
    ISSN 0019-2805 ; 0953-4954
    DOI 10.1111/imm.13651
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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    Ud II Zs.181: Hefte anzeigen Standort:
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    Dieser Service ist kostenpflichtig (siehe Lieferbedingungen von subito). Bestellungen, die einen Artikel nebst Supplementary Material umfassen, werden grundsätzlich wie mehrfache Bestellungen bearbeitet. Gebühren fallen in diesen Fällen für jede einzelne Bestellung an.

  5. Artikel ; Online: Identification of differences in the magnitude and specificity of SARS-CoV-2 nucleocapsid antibody responses in naturally infected and vaccinated individuals

    Pushpakumara, Pradeep D / Jeewandara, Chandima / Bary, Farha / Madushanka, Deshan / Perera, Lahiru / Aberathna, Inoka S / Nimasha, Thashmi / Jayamali, Jeewantha / Ranasinghe, Thushali / Kuruppu, Heshan / Danasekara, Saubhagya / Wijewickrama, Ananda / Ogg, Graham / Malavige, Gathsaurie Neelika

    medRxiv

    Abstract: Background: As there are limited data on B cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan ... ...

    Abstract Background: As there are limited data on B cell epitopes for the nucleocapsid protein in SARS-CoV-2, we sought to identify the immunodominant regions within the N protein, recognized by patients with varying severity of natural infection with the Wuhan strain (WT), delta, omicron and in those who received the Sinopharm vaccines, which is an inactivated, whole virus vaccine. Methods: Using overlapping peptides representing the N protein, with an in-house ELISA, we mapped the immunodominant regions within the N protein, in seronegative (n=30), WT infected (n=30), delta infected (n=30), omicron infected+vaccinated (n=20) and Sinopharm (BBIBP-CorV) vaccinees (n=30). We then investigated the sensitivity and specificity of these immunodominant regions and analysed their conservation with other SARS-CoV-2 variants of concern, seasonal human coronaviruses and bat Sarbecoviruses. We then investigated the kinetics of responses to these regions in those with varying severity of acute COVID-19. Results: We identified four immunodominant regions aa 29-52, aa 155-178, aa 274 to 297 and aa 365 to 388, were highly conserved within SARS-CoV-2 and the bat coronaviruses. The magnitude of responses to these regions varied based on the infecting SARS-CoV-2 variants, with WT infected individuals predominantly recognizing aa155 to 178 regions, delta infected individuals and vaccinated+omicron infected individuals predominantly recognizing regions aa 29 to 52 and aa 274 to 294 regions. Sinopharm vaccinees recognized all four regions, with the magnitude of responses significantly lower than other groups. >80% of individuals gave responses above the positive cut-off threshold to many of the four regions, with some differences with individuals who were infected with different VoCs. These regions were found to be 100% specific, as none of the seronegative individuals gave any responses. Conclusions: N-protein specific responses appear to be detectable in over 90% of those who were naturally infected or vaccinated with a whole virus inactivated vaccine, with responses mainly directed against four regions of the protein, which were highly conserved. As these regions were highly specific with high sensitivity, they have a potential to be used to develop diagnostic assays and to be used in development of vaccines.
    Schlagwörter covid19
    Sprache Englisch
    Erscheinungsdatum 2023-01-07
    Verlag Cold Spring Harbor Laboratory Press
    Dokumenttyp Artikel ; Online
    DOI 10.1101/2023.01.05.23284247
    Datenquelle COVID19

    Volltext online

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