REACTOGENICITY OF HETEROLOGOUS MRNA-BASED COVID-19 VACCINE BOOSTER IN YOUNG ADULTS IN INDONESIA- A SHORT COMMUNICATION.

Background: Heterologous priming with the inactivated SARS-CoV-2 vaccine (CoronaVac) and boosting with mRNA-based COVID-19 vaccine (Moderna or Pfizer) is currently recommended in Indonesia. The reactogenicity data of these heterologous vaccine regimens are not entirely available, particularly in young adults. The present study, therefore, aimed to evaluate the solicited local and systemic reactions in the first seven days post-vaccination either with Moderna or Pfizer vaccine among previous recipients of two doses of CoronaVac. Materials and Methods: An electronic-based cross-sectional study was conducted among medical students at the Pelita Harapan University, Banten, Indonesia, who received mRNA-based COVID-19 vaccine following two doses of CoronaVac. Samples were collected using a cluster sampling technique. Comparison between groups was performed by Fisher's exact test. Results: A total of 72 participants, 23 (32%) of which received the Moderna vaccine and 49 (68%) received the Pfizer vaccine, were included in this study. The median age of participants was 21 (IQR 19-22) years old. The most common local and systemic events for mRNA-based COVID-19 vaccines were injection site pain, fever, headache, fatigue, myalgia, and arthralgia. Solicited local and systemic reactions were reported more frequently in Moderna recipients than Pfizer recipients. Most local and systemic reactions were graded as mild to moderate and did not lead to hospitalization. Conclusions: The reactogenicity of the heterologous prime-boost with CoronaVac and mRNA-based COVID-19 vaccine booster among young adults is reassuring, and no unexpected concerns were identified.

Safety and Immunogenicity of a Single Dose of BNT162b2 COVID-19 mRNA Vaccine in a Warfarin-Treated Protein S Deficient Patient: A Case Report and Literature Review.

Patients with protein S (PS) deficiency possibly have a higher risk of developing severe COVID-19 disease. Therefore, vaccination against SARS-CoV-2 infections is recommended for PS-deficient patients. However, there are limited data regarding the safety and immunogenicity of the currently available COVID-19 mRNA vaccine in PS-deficient patients. We report a case of monitoring the antibody response of a 40-year-old female diagnosed with PS deficiency and on warfarin treatment following a single dose of BNT162b2 mRNA vaccine. Antibody against the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein (anti-S) was measured on days 7, 14, and 21 after vaccination. Seroconversion was detected on day 21 but was possibly lower than the anti-S level previously reported in healthy individuals after receiving the first dose of the BNT162b2 mRNA vaccine. There were no local and systemic events reported up to 7 days in this patient after vaccination. This case highlights that the administration of the BNT162b2 vaccine had a favourable safety profile, and the second dose of the vaccine is required to provide the optimal protection against SARS-CoV-2 infection in PS-deficient patients.

Recurrence of Asymptomatic COVID-19 after Recovery among Healthcare Workers.

We describe five healthcare workers (HCWs) with a recurrence of asymptomatic SARS-CoV-2 infection at Siloam Teaching Hospital, Indonesia. All cases involved nurses, with an average age of 27 years. The RT-PCR assay confirmed the first and second infection episodes. All cases showed negative RT-PCR results in the period between two infection episodes. The median interval time between two infection episodes was 123 days, ranging from 92 to 158 days. The clinical outcomes for all cases were favourable, with no mortality observed among study cases. Further studies will be required to understand the true nature of this phenomenon.

Antibody response after a third dose mRNA-1273 vaccine among vaccinated healthcare workers with two doses of inactivated SARS-CoV-2 vaccine.

BACKGROUND: Health care workers (HCWs), a high-risk group for contracting COVID-19 disease, are being prioritized to receive COVID-19 vaccination. A third dose messenger RNA (mRNA) vaccine, mRNA-1273 (Moderna), after 2 doses of inactivated vaccine (CoronaVac), has been used to increase the level of protection against SARS-CoV-2 among Indonesian HCWs. However, data regarding antibody response after mRNA-1273 booster dose are limited. OBJECTIVE: To evaluate the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein (anti-S) titers induced by the third mRNA-1273 vaccine among fully vaccinated HCWs with CoronaVac. RESULTS: A total of 90 HCWs with no history of SARS-CoV-2 infection and who had received the third dose of vaccination were included in this study. The mRNA-1273 vaccine booster was administered 6 months after completing primary vaccination with CoronaVac. After the third dose, the anti-S antibodies level significantly increased, from a median of 41.7 U/mL (interquartile range [IQR], 22.4-92.5) to 28 394 U/mL (IQR, 20 837-41 646) (p <0.0001). After the third dose, seropositivity with the anti-S antibodies level >210 U/mL was observed in all HCWs. Age was negatively associated with the anti-S antibodies level after the mRNA-1273 booster. CONCLUSION: The heterologous prime booster with CoronaVac and mRNA-1273 vaccine booster elicit a pronounced antibody response against SARS-CoV-2 infection.

Co-Occurrence of SARS-CoV-2 Infection and Inactivated SARS-CoV-2 Vaccination among Healthcare Workers.

The presented cases describe the concurrent SARS-CoV-2 infection and inactivated SARS-CoV-2 vaccination among eight healthcare workers (HCWs). These cases highlighted the importance of broad hospital screening during the COVID-19 vaccination campaign. Further study regarding the durability of antibody response induced by infection and first-dose vaccination is required to determine the appropriate time for giving a second dose of inactivated SARS-CoV-2 vaccine among these cases.

Antibody response to the inactivated SARS-CoV-2 vaccine among healthcare workers, Indonesia.

BACKGROUND: As healthcare workers (HCWs) are at high risk for infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), they have priority for receipt of the coronavirus disease 2019 (COVID-19) vaccine. The inactivated SARS-CoV-2 vaccine has been used in Indonesia to induce an antibody response against SARS-CoV-2 infection in HCWs. However, information regarding the kinetics of antibodies induced by this vaccine remains scarce. OBJECTIVE: To investigate the magnitude and durability of antibodies against the spike (S) protein (anti-S) in fully-vaccinated HCWs using an electrochemiluminescence immunoassay. RESULTS: Seroconversion of anti-S antibodies was observed among 159 (99.4%) of 160 HCWs without prior SARS-CoV-2 infection 14 days after full-dose vaccination. The level of anti-S antibodies decreased significantly by day 42 post-vaccination compared with day 14 post-vaccination, but persisted for up to 98 days post-vaccination. In contrast, vaccinated HCWs with prior SARS-CoV-2 infection had significantly higher, stable levels of anti-S antibodies compared with vaccinated HCWs without prior SARS-CoV-2 infection. CONCLUSION: The remarkable decline and lower level of anti-S antibodies among HCWs without prior SARS-CoV-2 infection may indicate the need for an additional booster dose of SARS-CoV-2 vaccine for protection against COVID-19. This study of antibody responses induced by the inactivated SARS-CoV-2 vaccine among HCWs may contribute to future policy decisions regarding vaccination.

Prognostic value of inflammatory markers in patients with COVID-19 in Indonesia.

BACKGROUND & AIMS: Coronavirus disease 2019 (COVID-19) has a wide clinical spectrum, ranging from asymptomatic infection to severe diseases with high mortality rate. Early identification of high-risk COVID-19 patients may be beneficial to reduce morbidity and in-hospital mortality. This study aimed to investigate whether baseline levels of inflammatory markers such as C-reactive protein (CRP) and immune-cell-based inflammatory indices, neutrophil to lymphocyte ratio (NLR), derived-NLR (d-NLR), and platelet to lymphocyte ratio (PLR) at hospital admission are associated with adverse disease outcomes in COVID-19 patients. METHODS: Clinical data from 391 hospitalized COVID-19 patients in three Siloam Hospitals in Indonesia were retrospectively collected and analysed from March 20 to October 30, 2020. RESULTS: Fifty-four (13.8%) hospitalized patients had clinical deterioration and required ICU treatment, categorizing them as severe COVID-19 cases. Older age, presence of underlying diseases, and increased inflammatory markers values at admission were significantly associated with severe cases. After adjustment of sociodemographic and comorbidities factors, CRP, NLR, and d-NLR values, but not PLRs, were identified as independent risk factors for disease severity and death in COVID-19 patients. The area under curve (AUC) of CRP, NLR, and d-NLR were 0.854, 0.848, and 0.854, respectively. The optimal cut-off points for CRP, NLR, and d-NLR for identification of COVID-19 patients with potential worse disease outcomes were 47 mg/L, 6, and 4, respectively. CONCLUSION: Initial assessment of CRP, NLR, and d-NLR values at hospital admission may be important predictors for adverse disease outcomes in COVID-19 patients.

Post-vaccination cases of COVID-19 among healthcare workers at Siloam Teaching Hospital, Indonesia.

BACKGROUND: Healthcare workers (HCWs) are at increased risk of exposure to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), compared with the general population. Therefore, they are given priority for the COVID-19 vaccine in the national COVID-19 vaccination campaign in Indonesia. However, while the daily number of new COVID-19 cases remains high, and data regarding the efficacy of the vaccine in healthcare settings remain unavailable, vaccinated HCWs remain at risk of COVID-19 infection and further transmission. OBJECTIVE: To identify cases of COVID-19 among vaccinated HCWs at Siloam Teaching Hospital, Indonesia via active and passive surveillance conducted by the hospital's COVID-19 infection prevention and control unit. RESULTS: Of 1040 HCWs who had received two doses of the COVID-19 vaccine, 13 (1.25%) tested positive for SARS-CoV-2 RNA on reverse transcriptase polymerase chain reaction between 2 and 11 days (median 5 days) after the second vaccination. CONCLUSION: Laboratory-confirmed COVID-19 among vaccinated HCWs soon after the second vaccination indicates that HCWs remain at risk of COVID-19. Therefore, the presence of symptoms soon after full vaccination cannot be considered as vaccine-related symptoms, and regular COVID-19 testing should be conducted among HCWs.

Expansion of dysfunctional CD56-CD16+ NK cells in chronic hepatitis B patients.

BACKGROUND & AIMS: Natural killer (NK) cells are primary innate effector cells that play an important role in the control of human viral infections. During chronic viral infection, NK cells undergo significant changes in phenotype, function and subset distribution, including the appearance of CD56-CD16+ (CD56-) NK cells, previously identified in chronic human immunodeficiency virus (HIV) and hepatitis C virus infection. However, the presence of CD56- NK cells in the pathogenesis of chronic hepatitis B (CHB) remains unknown. METHODS: Phenotype and function of CD56- NK cells from patients with CHB (n = 28) were assessed using flow cytometry and in vitro stimulation with HBV antigen. RESULTS: CHB patients had a higher frequency of CD56- NK cells compared to healthy controls in peripheral blood (6.2% vs 1.4%, P < .0001). Compared to CD56+ NK cells, CD56- NK cells had increased expression of inhibitory receptors, and reduced expression of activating receptors, as measured by MFI and qPCR. CD56- NK cells were less responsive to target cell and cytokine stimulation compared to their CD56+ counterparts. In addition, CD56- NK cells demonstrated defective dendritic cells (DCs) interactions resulting in reduced DCs maturation, lower expression of NK CD69 and impaired capacity of NK cells to eliminate immature DCs in co-culture studies. Finally, frequency of CD56- NK cells was positively correlated with serum HBV DNA levels. CONCLUSION: Chronic HBV infection induces the expansion of highly dysfunctional of CD56- NK cells that likely contribute to inefficient innate and adaptive antiviral immune response in chronic HBV infection.

HBV vaccination and HBV infection induces HBV-specific natural killer cell memory.

OBJECTIVE: Vaccination against hepatitis B virus (HBV) confers protection from subsequent infection through immunological memory that is traditionally considered the domain of the adaptive immune system. This view has been challenged following the identification of antigen-specific memory natural killer cells (mNKs) in mice and non-human primates. While the presence of mNKs has been suggested in humans based on the expansion of NK cells following pathogen exposure, evidence regarding antigen-specificity is lacking. Here, we demonstrate the existence of HBV-specific mNKs in humans after vaccination and in chronic HBV infection. DESIGN: NK cell responses were evaluated by flow cytometry and ELISA following challenge with HBV antigens in HBV vaccinated, non-vaccinated and chronic HBV-infected individuals. RESULTS: NK cells from vaccinated subjects demonstrated higher cytotoxic and proliferative responses against autologous hepatitis B surface antigen (HBsAg)-pulsed monocyte-derived dendritic cells (moDCs) compared with unvaccinated subjects. Moreover, NK cell lysis of HBsAg-pulsed moDCs was significantly higher than that of hepatitis B core antigen (HBcAg)-pulsed moDCs (non-vaccine antigen) or tumour necrosis factor α-activated moDCs in a NKG2D-dependent manner. The mNKs response was mediated by CD56dim NK cells coexpressing CD57, CD69 and KLRG1. Further, mNKs from chronic hepatitis B patients exhibited greater degranulation against HBcAg-pulsed moDCs compared with unvaccinated or vaccinated patients. Notably, mNK activity was negatively correlated with HBV DNA levels. CONCLUSIONS: Our data support the presence of a mature mNKs following HBV antigen exposure either through vaccination or infection. Harnessing these antigen specific, functionally active mNKs provides an opportunity to develop novel treatments targeting HBV in chronic infection.

Hepatitis C Virus (HCV) Eradication With Interferon-Free Direct-Acting Antiviral-Based Therapy Results in KLRG1+ HCV-Specific Memory Natural Killer Cells.

Direct acting antiviral therapies rapidly clear chronic hepatitis C virus (HCV) infection and restore natural killer (NK) cell function. We investigated NK-cell memory formation following HCV clearance by examining NK-cell phenotype and responses from control and chronic HCV patients before and after therapy following sustained virologic response at 12 weeks post therapy (SVR12). NK-cell phenotype at SVR12 differed significantly from paired pretreatment samples, with an increase in maturation markers CD16, CD57, and KLRG1. HCV patients possessed stronger cytotoxic responses against HCV-infected cells as compared to healthy controls; a response that further increased following SVR12. The antigen-specific response was mediated by KLRG1+ NK cells, as demonstrated by increased degranulation and proliferation in response to HCV antigen only. Our data suggest that KLRG1+ HCV-specific memory NK cells develop following viral infection, providing insight into their role in HCV clearance and relevance with regard to vaccine design.

Macrophage Coordination of the Interferon Lambda Immune Response.

Lambda interferons (IFN-λs) are a major component of the innate immune defense to viruses, bacteria, and fungi. In human liver, IFN-λ not only drives antiviral responses, but also promotes inflammation and fibrosis in viral and non-viral diseases. Here we demonstrate that macrophages are primary responders to IFN-λ, uniquely positioned to bridge the gap between IFN-λ producing cells and lymphocyte populations that are not intrinsically responsive to IFN-λ. While CD14+ monocytes do not express the IFN-λ receptor, IFNLR1, sensitivity is quickly gained upon differentiation to macrophages in vitro. IFN-λ stimulates macrophage cytotoxicity and phagocytosis as well as the secretion of pro-inflammatory cytokines and interferon stimulated genes that mediate immune cell chemotaxis and effector functions. In particular, IFN-λ induced CCR5 and CXCR3 chemokines, stimulating T and NK cell migration, as well as subsequent NK cell cytotoxicity. Using immunofluorescence and cell sorting techniques, we confirmed that human liver macrophages expressing CD14 and CD68 are highly responsive to IFN-λ ex vivo. Together, these data highlight a novel role for macrophages in shaping IFN-λ dependent immune responses both directly through pro-inflammatory activity and indirectly by recruiting and activating IFN-λ unresponsive lymphocytes.

KLRG1+ natural killer cells exert a novel antifibrotic function in chronic hepatitis B.

BACKGROUND & AIMS: Natural killer (NK) cells are known to exert strong antiviral activity. Killer cell lectin-like receptor subfamily G member 1 (KLRG1) is expressed by terminally differentiated NK cells and KLRG1-expressing lymphocytes are known to expand following chronic viral infections. We aimed to elucidate the previously unknown role of KLRG1 in the pathogenesis of chronic hepatitis B (CHB). METHODS: KLRG1+ NK cells were taken from the blood and liver of healthy individuals and patients with CHB. The phenotype and function of these cells was assessed using flow cytometry and in vitro stimulation. RESULTS: Patients with CHB had a higher frequency of KLRG1+ NK cells compared to healthy controls (blood 13.4 vs. 2.3%, p <0.0001 and liver 23.4 vs. 2.6%, p <0.01). KLRG1+ NK cells were less responsive to K562 and cytokine stimulation, but demonstrated enhanced cytotoxicity (9.0 vs. 4.8%, p <0.05) and IFN-γ release (8.0 vs. 1.5%, p <0.05) via antibody dependent cellular cytotoxicity compared to their KLRG1- counterparts. KLRG1+ NK cells possessed a mature phenotype, demonstrating stronger cytolytic activity and IFN-γ secretion against hepatic stellate cells (HSCs) than KLRG1- NK cells. Moreover, KLRG1+ NK cells more effectively induced primary HSC apoptosis in a TRAIL-dependent manner. Increased KLRG1+ NK cell frequency in the liver and blood was associated with lower fibrosis stage (F0/F1) in patients with CHB. Finally, the expression of CD44, degranulation and IFN-γ production were all increased in KLRG1+ NK cells following stimulation with osteopontin, the CD44 ligand, suggesting that HSC-derived osteopontin may cause KLRG1+ NK cell activation. CONCLUSIONS: KLRG1+ NK cells likely play an antifibrotic role during the natural course of CHB infection. Harnessing this antifibrotic function may provide a novel therapeutic approach to treat liver fibrosis in patients with CHB. LAY SUMMARY: Individuals that are chronically infected with hepatitis B virus (HBV) possess an increased number of immune cells, called natural killer (NK) cells expressing the surface marker KLRG1 in the blood and liver. Here, we demonstrate that these specific NK cells are able to kill activated stellate cells in the liver. Because activated stellate cells contribute to liver scarring, i.e. fibrosis, and subsequent liver dysfunction in individuals with chronic HBV infection, KLRG1+ NK cells are a novel immune cell type that can limit liver scarring.

Unzipping the cuticle of the human hair shaft to obtain micron/nano keratin filaments.

An attempt has been made to obtain intact individual keratin filaments of various levels from micron cortical, micron macrofibril to nano intermediate filament and polypeptide alpha-helix from the human hair shaft. The feasibility of this initiative has been largely demonstrated by finding that there is a longitudinal seam/zipper on the cuticle of the human hair shaft, which can be unzipped by certain solvents such as performic acid and urea, allowing one to use an anatomical approach to separate intact individual micron/nano filaments. Micron cortical and macrofibril filaments have been obtained. It is also found that the cortical filaments are twisted together to form a yarn, giving rise to the strength for the hair shaft; and that individual cortical filaments are often 2-2 paired in a similar structure to the double helix.