Displaying publications 1 - 20 of 81 in total

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  1. Ball HJ, Jusof FF, Bakmiwewa SM, Hunt NH, Yuasa HJ
    Front Immunol, 2014;5:485.
    PMID: 25346733 DOI: 10.3389/fimmu.2014.00485
    Indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) are tryptophan-degrading enzymes that have independently evolved to catalyze the first step in tryptophan catabolism via the kynurenine pathway (KP). The depletion of tryptophan and formation of KP metabolites modulates the activity of the mammalian immune, reproductive, and central nervous systems. IDO and TDO enzymes can have overlapping or distinct functions depending on their expression patterns. The expression of TDO and IDO enzymes in mammals differs not only by tissue/cellular localization but also by their induction by distinct stimuli. To add to the complexity, these genes also have undergone duplications in some organisms leading to multiple isoforms of IDO or TDO. For example, many vertebrates, including all mammals, have acquired two IDO genes via gene duplication, although the IDO1-like gene has been lost in some lower vertebrate lineages. Gene duplications can allow the homologs to diverge and acquire different properties to the original gene. There is evidence for IDO enzymes having differing enzymatic characteristics, signaling properties, and biological functions. This review analyzes the evolutionary convergence of IDO and TDO enzymes as tryptophan-catabolizing enzymes and the divergent evolution of IDO homologs to generate an enzyme family with diverse characteristics not possessed by TDO enzymes, with an emphasis on the immune system.
  2. Chan CM, Abdul Latiff AH, Noh LM, Ismail IH, Abd Hamid IJ, Liew WK, et al.
    Front Immunol, 2023;14:1209315.
    PMID: 37529038 DOI: 10.3389/fimmu.2023.1209315
    INTRODUCTION: With increased diagnostic capabilities and treatment modalities in the field of primary immunodeficiencies (PID), many pediatric patients survive beyond childhood and experience a change of care to the adult-oriented healthcare system. Unfortunately, the transition pathways for PID are less clearly defined, resulting in deterioration of quality of care in adulthood. Hence, this is the first regional study to address PID clinicians' opinions on practices and challenges of transition care in 7 Southeast Asia (SEA) countries.

    METHODS: We adopted a cross-sectional study design through an online survey platform to enquire opinions of transition practices from expert representatives in 7 SEA countries.

    RESULTS: Regionally, 3 out 7 countries reported having no practice of transition care. Among cited challenges were reluctant adaptation by patients and caregivers to unfamiliarized adult healthcare systems, inadequate ratio of adult immunologists to patients and lack of facilities for transfer.

    DISCUSSION AND CONCLUSION: Our study provides evidence to advocate policy makers on the importance of standardized integration of transition practice towards betterment of transiting PID patients into adulthood.

  3. Rich AM, Hussaini HM, Parachuru VP, Seymour GJ
    Front Immunol, 2014;5:464.
    PMID: 25309546 DOI: 10.3389/fimmu.2014.00464
    It is becoming increasingly apparent that the tumor microenvironment plays an important role in the progression of cancer. The microenvironment may promote tumor cell survival and proliferation or, alternatively may induce tumor cell apoptosis. Toll-like receptors (TLRs) are transmembrane proteins, expressed on immune cells and epithelial cells, that recognize exogenous and endogenous macromolecules. Once activated, they initiate signaling pathways leading to the release of cytokines and chemokines, which recruit immune cells inducing further cytokine production, the production of angiogenic mediators and growth factors, all of which may influence tumor progression. This paper examines the actions of TLRs in carcinogenesis with particular emphasis on their role in oral squamous cell carcinoma.
  4. Chiang C, Li Y, Ng SK
    Front Immunol, 2020;11:625504.
    PMID: 33613567 DOI: 10.3389/fimmu.2020.625504
    Both DNA and RNA can maintain left-handed double helical Z-conformation under physiological condition, but only when stabilized by Z-DNA binding domain (ZDBD). After initial discovery in RNA editing enzyme ADAR1, ZDBD has also been described in pathogen-sensing proteins ZBP1 and PKZ in host, as well as virulence proteins E3L and ORF112 in viruses. The host-virus antagonism immediately highlights the importance of ZDBD in antiviral innate immunity. Furthermore, Z-RNA binding has been shown to be responsible for the localization of these ZDBD-containing proteins to cytoplasmic stress granules that play central role in coordinating cellular response to stresses. This review sought to consolidate current understanding of Z-RNA sensing in innate immunity and implore possible roles of Z-RNA binding within cytoplasmic stress granules.
  5. Nordin J, Solís L, Prévot J, Mahlaoui N, Chapel H, Sánchez-Ramón S, et al.
    Front Immunol, 2021;12:780140.
    PMID: 34868053 DOI: 10.3389/fimmu.2021.780140
    A global gold standard framework for primary immunodeficiency (PID) care, structured around six principles, was published in 2014. To measure the implementation status of these principles IPOPI developed the PID Life Index in 2020, an interactive tool aggregating national PID data. This development was combined with a revision of the principles to consider advances in the field of health and science as well as political developments since 2014. The revision resulted in the following six principles: PID diagnosis, treatments, universal health coverage, specialised centres, national patient organisations and registries for PIDs. A questionnaire corresponding to these principles was sent out to IPOPI's national member organisations and to countries in which IPOPI had medical contacts, and data was gathered from 60 countries. The data demonstrates that, regardless of global scientific progress on PIDs with a growing number of diagnostic tools and better treatment options becoming available, the accessibility and affordability of these remains uneven throughout the world. It is not only visible between regions, but also between countries within the same region. One of the most urgent needs is medical education. In countries without immunologists, patients with PID suffer the risk of remaining undiagnosed or misdiagnosed, resulting in health implications or even death. Many countries also lack the infrastructure needed to carry out more advanced diagnostic tests and perform treatments such as hematopoietic stem cell transplantation or gene therapy. The incapacity to secure appropriate diagnosis and treatments affects the PID environment negatively in these countries. Availability and affordability also remain key issues, as diagnosis and treatments require coverage/reimbursement to ensure that patients with PID can access them in practice, not only in theory. This is still not the case in many countries of the world according to the PID Life Index. Although some countries do perform better than others, to date no country has fully implemented the PID principles of care, confirming the long way ahead to ensure an optimal environment for patients with PID in every country.
  6. Al-Herz W, Al-Ahmad M, Al-Khabaz A, Husain A, Sadek A, Othman Y
    Front Immunol, 2019;10:1754.
    PMID: 31396239 DOI: 10.3389/fimmu.2019.01754
    Objective: To present the report from the Kuwait National Primary Immunodeficiency Registry between 2004 and 2018. Methods: The patients were followed prospectively between January 2004 and December 2018 and their collected data included sociodemographic, diagnosis, clinical presentation, laboratory tests, and treatment. Results: A total of 314 PID patients (165 males and 149 females) were registered during the study period. Most of the patients (n = 287, 91.4%) were Kuwaiti nationals and the prevalence among Kuwaitis was 20.27/100,000 with a cumulative incidence of 24.96/100,000 Kuwaitis. The distribution of the patients according to PID categories was as follow: immunodeficiencies affecting cellular and humoral immunity, 100 patients (31.8%); combined immunodeficiencies with associated syndromic features, 68 patients (21.7%); predominantly antibody deficiencies, 56 patients (17.8%); diseases of immune dysregulation, 47 patients (15%); congenital defects of phagocyte number or function, 20 patients (6.4%); autoinflammatory disorders, 1 patient (0.3%); and complement deficiencies, 22 patients (7%). The mean age of the patients at onset of symptoms was 26 months while the mean age at diagnosis was 53 months and the mean delay in diagnosis was 27 months. Most of the patients (n = 272, 86%) had onset of symptoms before the age of 5 years. Parental consanguinity rate within the registered patients was 78% and a positive family history of PID was noticed in 50% of the patients. Genetic testing was performed in 69% of the patients with an overall diagnostic yield of 90%. Mutations were identified in 46 different genes and more than 90% of the reported genetic defects were transmitted by an autosomal recessive pattern. Intravenous immunoglobulins and stem cell transplantation were used in 58% and 25% of the patients, respectively. There were 81 deaths (26%) among the registered patients with a mean age of death of 25 months. Conclusions: PID is not infrequent in Kuwait and the reported prevalence is the highest in the literature with increased proportion of more severe forms. Collaborative efforts including introduction of newborn screening should be implemented to diagnose such cases earlier and improve the quality of life and prevent premature deaths.
  7. Ahmad S, Azid NA, Boer JC, Lim J, Chen X, Plebanski M, et al.
    Front Immunol, 2018;9:2572.
    PMID: 30473698 DOI: 10.3389/fimmu.2018.02572
    Tumor necrosis factor-alpha (TNF) is a pleiotropic cytokine, which is thought to play a major role in the pathogenesis of inflammatory diseases, including allergy. TNF is produced at the early stage of allergen sensitization, and then continues to promote the inflammation cascade in the effector phase of allergic reactions. Consequently, anti-TNF treatment has been proposed as a potential therapeutic option. However, recent studies reveal anti-intuitive effects of TNF in the activation and proliferative expansion of immunosuppressive Tregs, tolerogenic DCs and MDSCs. This immunosuppressive effect of TNF is mediated by TNFR2, which is preferentially expressed by immunosuppressive cells. These findings redefine the role of TNF in allergic reaction, and suggest that targeting TNF-TNFR2 interaction itself may represent a novel strategy in the treatment of allergy.
  8. Dass SA, Balakrishnan V, Arifin N, Lim CSY, Nordin F, Tye GJ
    Front Immunol, 2022;13:833715.
    PMID: 35242137 DOI: 10.3389/fimmu.2022.833715
    2020 will be marked in history for the dreadful implications of the COVID-19 pandemic that shook the world globally. The pandemic has reshaped the normality of life and affected mankind in the aspects of mental and physical health, financial, economy, growth, and development. The focus shift to COVID-19 has indirectly impacted an existing air-borne disease, Tuberculosis. In addition to the decrease in TB diagnosis, the emergence of the TB/COVID-19 syndemic and its serious implications (possible reactivation of latent TB post-COVID-19, aggravation of an existing active TB condition, or escalation of the severity of a COVID-19 during TB-COVID-19 coinfection), serve as primary reasons to equally prioritize TB. On a different note, the valuable lessons learnt for the COVID-19 pandemic provide useful knowledge for enhancing TB diagnostics and therapeutics. In this review, the crucial need to focus on TB amid the COVID-19 pandemic has been discussed. Besides, a general comparison between COVID-19 and TB in the aspects of pathogenesis, diagnostics, symptoms, and treatment options with importance given to antibody therapy were presented. Lastly, the lessons learnt from the COVID-19 pandemic and how it is applicable to enhance the antibody-based immunotherapy for TB have been presented.
  9. Szakmany T, Fitzgerald E, Garlant HN, Whitehouse T, Molnar T, Shah S, et al.
    Front Immunol, 2023;14:1308530.
    PMID: 38332914 DOI: 10.3389/fimmu.2023.1308530
    INTRODUCTION: Early diagnosis of sepsis and discrimination from SIRS is crucial for clinicians to provide appropriate care, management and treatment to critically ill patients. We describe identification of mRNA biomarkers from peripheral blood leukocytes, able to identify severe, systemic inflammation (irrespective of origin) and differentiate Sepsis from SIRS, in adult patients within a multi-center clinical study.

    METHODS: Participants were recruited in Intensive Care Units (ICUs) from multiple UK hospitals, including fifty-nine patients with abdominal sepsis, eighty-four patients with pulmonary sepsis, forty-two SIRS patients with Out-of-Hospital Cardiac Arrest (OOHCA), sampled at four time points, in addition to thirty healthy control donors. Multiple clinical parameters were measured, including SOFA score, with many differences observed between SIRS and sepsis groups. Differential gene expression analyses were performed using microarray hybridization and data analyzed using a combination of parametric and non-parametric statistical tools.

    RESULTS: Nineteen high-performance, differentially expressed mRNA biomarkers were identified between control and combined SIRS/Sepsis groups (FC>20.0, p<0.05), termed 'indicators of inflammation' (I°I), including CD177, FAM20A and OLAH. Best-performing minimal signatures e.g. FAM20A/OLAH showed good accuracy for determination of severe, systemic inflammation (AUC>0.99). Twenty entities, termed 'SIRS or Sepsis' (S°S) biomarkers, were differentially expressed between sepsis and SIRS (FC>2·0, p-value<0.05).

    DISCUSSION: The best performing signature for discriminating sepsis from SIRS was CMTM5/CETP/PLA2G7/MIA/MPP3 (AUC=0.9758). The I°I and S°S signatures performed variably in other independent gene expression datasets, this may be due to technical variation in the study/assay platform.

  10. Saeidi A, Zandi K, Cheok YY, Saeidi H, Wong WF, Lee CYQ, et al.
    Front Immunol, 2018;9:2569.
    PMID: 30473697 DOI: 10.3389/fimmu.2018.02569
    T-cell exhaustion is a phenomenon of dysfunction or physical elimination of antigen-specific T cells reported in human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections as well as cancer. Exhaustion appears to be often restricted to CD8+ T cells responses in the literature, although CD4+ T cells have also been reported to be functionally exhausted in certain chronic infections. Although our understanding of the molecular mechanisms associated with the transcriptional regulation of T-cell exhaustion is advancing, it is imperative to also explore the central mechanisms that control the altered expression patterns. Targeting metabolic dysfunctions with mitochondrion-targeted antioxidants are also expected to improve the antiviral functions of exhausted virus-specific CD8+ T cells. In addition, it is crucial to consider the contributions of mitochondrial biogenesis on T-cell exhaustion and how mitochondrial metabolism of T cells could be targeted whilst treating chronic viral infections. Here, we review the current understanding of cardinal features of T-cell exhaustion in chronic infections, and have attempted to focus on recent discoveries, potential strategies to reverse exhaustion and reinvigorate optimal protective immune responses in the host.
  11. Abd Hamid IJ, Azman NA, Gennery AR, Mangantig E, Hashim IF, Zainudeen ZT
    Front Immunol, 2020;11:1923.
    PMID: 32983118 DOI: 10.3389/fimmu.2020.01923
    Introduction: Primary immunodeficiency diseases (PIDs) are under-reported in Malaysia. The actual disease frequency of PID in this country is unknown due to the absence of a national patient registry for PID. Objective: This systematic review aimed to determine the prevalence rates of PID cases diagnosed and published in Malaysia from 1st of January 1979 until 1st of March 2020. It also aimed to describe the various types of PIDs reported in Malaysia. Method: Following the development of a comprehensive search strategy, all published literature of PID cases from Malaysia was identified and collated. All cases that fulfilled the International Union of Immunological Societies (IUIS) classification diagnosis were included in the systematic review. Data were retrieved and collated into a proforma. Results: A total of 4,838 articles were identified and screened, with 34 publications and 119 patients fulfilling the criteria and being included in the systematic review. The prevalence rate was 0.37 per 100,000 population. In accordance with the IUIS, the distribution of diagnostic classifications was immunodeficiencies affecting cellular and humoral immunities (36 patients, 30.3%), combined immunodeficiencies with associated or syndromic features (21 patients, 17.6%), predominant antibody deficiencies (24 patients, 20.2%), diseases of immune dysregulation (13 patients, 10.9%), congenital defects in phagocyte number or function (20 patients, 16.8%), defects in intrinsic and innate immunity (4 patients, 3.4%), and autoinflammatory disorders (1 patient, 0.8%). Parental consanguinity was 2.5%. Thirteen different gene mutations were available in 21.8% of the cases. Conclusion: PIDs are underdiagnosed and under-reported in Malaysia. Developing PID healthcare and a national patient registry is much needed to enhance the outcome of PID patient care.
  12. Mohamud R, LeMasurier JS, Boer JC, Sieow JL, Rolland JM, O'Hehir RE, et al.
    Front Immunol, 2017;8:1812.
    PMID: 29312323 DOI: 10.3389/fimmu.2017.01812
    Synthetic glycine coated 50 nm polystyrene nanoparticles (NP) (PS50G), unlike ambient NP, do not promote pulmonary inflammation, but instead, render lungs resistant to the development of allergic airway inflammation. In this study, we show that PS50G modulate the frequency and phenotype of regulatory T cells (Treg) in the lung, specifically increasing the proportion of tumor necrosis factor 2 (TNFR2) expressing Treg. Mice pre-exposed to PS50G, which were sensitized and then challenged with an allergen a month later, preferentially expanded TNFR2+Foxp3+ Treg, which further expressed enhanced levels of latency associated peptide and cytotoxic T-lymphocyte associated molecule-4. Moreover, PS50G-induced CD103+ dendritic cell activation in the lung was associated with the proliferative expansion of TNFR2+Foxp3+ Treg. These findings provide the first evidence that engineered NP can promote the selective expansion of maximally suppressing TNFR2+Foxp3+ Treg and further suggest a novel mechanism by which NP may promote healthy lung homeostasis.
  13. Zepeda-Ortega B, Goh A, Xepapadaki P, Sprikkelman A, Nicolaou N, Hernandez REH, et al.
    Front Immunol, 2021;12:608372.
    PMID: 34177882 DOI: 10.3389/fimmu.2021.608372
    The prevalence of food allergy has increased over the last 20-30 years, including cow milk allergy (CMA) which is one of the most common causes of infant food allergy. International allergy experts met in 2019 to discuss broad topics in allergy prevention and management of CMA including current challenges and future opportunities. The highlights of the meeting combined with recently published developments are presented here. Primary prevention of CMA should start from pre-pregnancy with a focus on a healthy lifestyle and food diversity to ensure adequate transfer of inhibitory IgG- allergen immune complexes across the placenta especially in mothers with a history of allergic diseases and planned c-section delivery. For non-breastfed infants, there is controversy about the preventive role of partially hydrolyzed formulae (pHF) despite some evidence of health economic benefits among those with a family history of allergy. Clinical management of CMA consists of secondary prevention with a focus on the development of early oral tolerance. The use of extensive Hydrolysate Formulae (eHF) is the nutrition of choice for the majority of non-breastfed infants with CMA; potentially with pre-, probiotics and LCPUFA to support early oral tolerance induction. Future opportunities are, among others, pre- and probiotics supplementation for mothers and high-risk infants for the primary prevention of CMA. A controlled prospective study implementing a step-down milk formulae ladder with various degrees of hydrolysate is proposed for food challenges and early development of oral tolerance. This provides a more precise gradation of milk protein exposure than those currently recommended.
  14. Al-Herz W, Essa S
    Front Immunol, 2019;10:1231.
    PMID: 31191561 DOI: 10.3389/fimmu.2019.01231
    Objective: To present the frequency and spectrum of viral infections in primary immunodeficient children. Methods: The data was obtained from the Kuwait National Primary Immunodeficiency Disorders (PIDs) Registry during the period of 2004-2018. Results: A total of 274 PID children were registered in KNPIDR during the study period with predominance of immunodeficiencies affecting cellular and humoral immunity, followed by combined immunodeficiencies with associated syndromic features and diseases of immune dysregulation. Overall infectious complications affected 82.4% of the patients, and viral infections affected 31.7% of the registered patients. Forty-five patients (16.4%) developed viral infections caused by at least 2 organisms, among those 20 patients were affected by three or more viral infections. There was a statistically significant association between viral infections and PID category. However, there was no statistically significant association between viral infections and gender or the patients' onset age. There was a total of 170 viral infections during the study period and the causes of these infections were predominated by CMV (22.2%), adenovirus (11.7%), EBV (11.1%), and enteroviruses (7.4%). CMV and parainfluenza infections were more common in the group of immunodeficiencies affecting cellular and humoral immunity while EBV and human papilloma virus (HPV) were more common in the immune dysregulation group and combined immunodeficiencies with associated syndromic features, respectively. The most common presentation was viremia (28.8%) followed by pneumonia (28.2%) and skin infections (17.6%). The most common causes of viremia were CMV followed by adenovirus and EBV, while the most common organisms causing pneumonia were CMV followed by rhinovirus and parainfluenza. There were 80 deaths among the registered patients, 10% were caused by viral infections. Conclusions: Viral infections are common in PIDs and result into a wide-range of clinical manifestations causing significant morbidity and mortality.
  15. Jumat NR, Chong MY, Seman Z, Jamaluddin R, Wong NK, Abdullah M
    Front Immunol, 2017;8:680.
    PMID: 28649252 DOI: 10.3389/fimmu.2017.00680
    Sexual dimorphism in immune response is widely recognized, but few human studies have observed this distinction. Food with endo-immunomodulatory potential may reveal novel sex-biased in vivo interactions. Immunomodulatory effects of Carica papaya were compared between healthy male and female individuals. Volunteers were given fixed meals supplemented with papaya for 2 days. Changes in blood immune profiles and hormone levels were determined. In females, total natural killer (NK) cell percentages decreased (12.7 ± 4.4 vs 14.6 ± 5.8%, p = 0.018, n = 18) while B cells increased (15.2 ± 5.5 vs 14.5 ± 5.0, p = 0.037, n = 18) after papaya consumption. Increased 17β-estradiol (511.1 ± 579.7 vs 282.7 ± 165.0 pmol/l, p = 0.036, n = 9) observed in females may be crucial to this change. Differentiation markers (CD45RA, CD69, CD25) analyzed on lymphocytes showed naïve (CD45RA(+)) non-CD4(+) lymphocytes were reduced in females (40.7 ± 8.1 vs 46.8 ± 5.4%, p = 0.012, n = 8) but not males. A general suppressive effect of papaya on CD69(+) cells, and higher percentage of CD69(+) populations in females and non-CD4 lymphocytes, may be relevant. CD107a(+) NK cells were significantly increased in males (16.8 ± 7.0 vs 14.7 ± 4.8, p = 0.038, n = 9) but not females. Effect in females may be disrupted by the action of progesterone, which was significantly correlated with this population (R = 0.771, p = 0.025, n = 8) after papaya consumption. In males, total T helper cells were increased (33.4 ± 6.4 vs 32.4 ± 6.1%, p = 0.040, n = 15). Strong significant negative correlation between testosterone and CD25(+)CD4(+) lymphocytes, may play a role in the lower total CD4(+) T cells reported in males. Thus, dissimilar immune profiles were elicited in the sexes after papaya consumption and may have sex hormone influence.
  16. Brandon-Mong GJ, Che Mat Seri NA, Sharma RS, Andiappan H, Tan TC, Lim YA, et al.
    Front Immunol, 2015;6:143.
    PMID: 25972863 DOI: 10.3389/fimmu.2015.00143
    A cross-sectional study was conducted to determine the seroepidemiology of Toxoplasma infection and its risk association among people having close contact with animals. A total of 312 blood samples were collected from veterinary personnel (veterinarian, technicians, and students) and pet owners from veterinary clinics and hospitals in the area of Klang Valley, Malaysia. About 4 cc of blood samples drawn from agreed participants were processed for measurement of anti-Toxoplasma IgG and IgM antibodies as well as avidity test of Toxoplasma IgG by ELISA I, II, and III kits. Meanwhile, the demographic profiles and possible risk factors of these participants were also recorded in the standardized data collection sheets. Overall seroprevalence of toxoplasmosis was observed in 62 (19.9%) participants being 7 (18.4%) in veterinarians, 15 (33.3%) in veterinary technicians, 29 (14.9%) in veterinary students, and 11 (31.4%) in pet owners. Of 19.9% Toxoplasma seropositive samples, 18.3% was positive for IgG antibody, 1.0% for IgM antibody, and 0.6% for both IgG and IgM antibodies. Of three different IgG avidity ELISA kits, ELISA III showed high avidity in all five seropositive samples (IgM and IgG/IgM antibodies) indicating chronic Toxoplasma infection which is consistent with no evidence of clinical toxoplasmosis diagnosed during the time of this study. Univariate analysis showed that age group, gender, study population, gardening, task performance, and working duration were significantly associated with Toxoplasma seropositivity. Further analysis by multivariate analysis using logistic regression showed that age group of ≥30 years old (OR = 0.34, 95% CI = 0.18-0.63, p = 0.001) and working or study duration of >10 years having close contact with animals (OR = 5.07, 95% CI = 1.80-14.24, p = 0.002) were identified as significant risks for Toxoplasma infection. Based on the results obtained, a comprehensive Toxoplasma screening and health surveillance program on toxoplasmosis should be implemented among people having close contact with animals in general and confirmed Toxoplasma seronegative individuals in particular to prevent seroconversion.
  17. Liew MNY, Kua KP, Lee SWH, Wong KK
    Front Immunol, 2023;14:1100263.
    PMID: 37701439 DOI: 10.3389/fimmu.2023.1100263
    INTRODUCTION: The COVID-19 pandemic is a major global public health crisis. More than 2 years into the pandemic, effective therapeutic options remain limited due to rapid viral evolution. Stemming from the emergence of multiple variants, several monoclonal antibodies are no longer suitable for clinical use. This scoping review aimed to summarize the preclinical and clinical evidence for bebtelovimab in treating newly emerging SARS-CoV-2 variants.

    METHODS: We systematically searched five electronic databases (PubMed, CENTRAL, Embase, Global Health, and PsycINFO) from date of inception to September 30, 2022, for studies reporting on the effect of bebtelovimab in SARS-CoV-2 infection, using a combination of search terms around -bebtelovimab‖, -LY-CoV1404‖, -LY3853113‖, and -coronavirus infection‖. All citations were screened independently by two researchers. Data were extracted and thematically analyzed based on study design by adhering to the stipulated scoping review approaches.

    RESULTS: Thirty-nine studies were included, thirty-four non-clinical studies were narratively synthesized, and five clinical studies were meta-analyzed. The non-clinical studies revealed bebtelovimab not only potently neutralized wide-type SARS-CoV-2 and existing variants of concern such as B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), and B.1.617.2 (Delta), but also retained appreciable activity against Omicron lineages, including BA.2.75, BA.4, BA.4.6, and BA.5. Unlike other monoclonal antibodies, bebtelovimab was able to bind to epitope of the SARS-CoV-2 S protein by exploiting loop mobility or by minimizing side-chain interactions. Pooled analysis from clinical studies depicted that the rates of hospitalization, ICU admission, and death were similar between bebtelovimab and other COVID-19 therapies. Bebtelovimab was associated with a low incidence of treatment-emergent adverse events.

    CONCLUSION: Preclinical evidence suggests bebtelovimab be a potential treatment for COVID-19 amidst viral evolution. Bebtelovimab has comparable efficacy to other COVID-19 therapies without evident safety concerns.

  18. Tan K, Zhang H, Lim LS, Ma H, Li S, Zheng H
    Front Immunol, 2019;10:3041.
    PMID: 32010132 DOI: 10.3389/fimmu.2019.03041
    Carotenoids are biologically active pigments that are well-known to enhance the defense and immunity of the vertebrate system. However, in invertebrates, the role of carotenoids in immunity is not clear. Therefore, this study aims to review the scientific evidence for the role of carotenoids in invertebrate immunization. From the analysis of published literatures and recent studies from our laboratory, it is obvious that carotenoids are involved in invertebrate immunity in two ways. On the one hand, carotenoids can act as antioxidant enzymes to remove singlet oxygen, superoxide anion radicals, and hydroxyl radicals, thereby reducing SOD activity and reducing the cost of immunity. In some organisms, carotenoids have been shown to promote SOD activity by up-regulating the expression of the ZnCuSOD gene. Carotenoids, on the other hand, play a role in the expression and regulation of many genes involved in invertebrate immunity, including thioredoxins (TRX), peptidoglycan recognition receptor proteins (PGRPs), ferritins, prophenoloxidase (ProPO), vitellogenin (Vg), toll-like receptor (TLRs), heat shock proteins (HSPs), and CuZnSOD gene. The information in this review is very useful for updating our understanding of the progress of carotenoid research in invertebrate immunology and to help identify topics for future topics.
  19. Ripen AM, Chiow MY, Rama Rao PR, Mohamad SB
    Front Immunol, 2021;12:778133.
    PMID: 34804071 DOI: 10.3389/fimmu.2021.778133
    Blended phenotypes exhibited by a patient may present a challenge to the establishment of diagnosis. In this study, we report a seven-year-old Murut girl with unusual features of Williams-Beuren syndrome (WBS), including recurrent infections and skin abscesses. Considering the possibility of a second genetic disorder, a mutation screening for genes associated with inborn errors of immunity (IEI) was conducted using whole exome sequencing (WES). Analysis of copy number variations (CNVs) from the exome data revealed a 1.53Mb heterozygous deletion on chromosome 7q11.23, corresponding to the known WBS. We also identified a biallelic loss of NCF1, which indicated autosomal recessive chronic granulomatous disease (CGD). Dihydrorhodamine (DHR) flow cytometric assay demonstrated abnormally low neutrophil oxidative burst activity. Coamplification of NCF1 and its pseudogenes identified a GT-deletion (ΔGT) at the start of exon 2 in NCF1 (NM_000265.7: c.75_76delGT: p.Tyr26Hisfs*26). Estimation of NCF1-to-NCF1 pseudogenes ratio using ΔGT and 20-bp gene scans affirmed nil copies of NCF1 in the patient. While the father had a normal ratio of 2:4, the mother had a ratio of 1:5, implicating the carrier of ΔGT-containing NCF1. Discovery of a 7q11.23 deletion involving one NCF1 allele and a ΔGT in the second NCF1 allele explained the coexistence of WBS and CGD in our patient. This study highlights the capability of WES to establish a molecular diagnosis for a case with blended phenotypes, enabling the provision of appropriate prophylactic treatment.
  20. Ismail NI
    Front Immunol, 2023;14:1166451.
    PMID: 37051244 DOI: 10.3389/fimmu.2023.1166451
    One would expect maternal immune cells to attack the invading trophoblast as the placenta is semi-allogenic. However, they appear to cooperate with the trophoblast in disrupting the arterial wall which has been determined in several studies. uNK cells are a particular type of immune cell that appears to play a role in pregnancy. As in pregnancy, the key contributors to trophoblast invasion appear to be a unique combination of genes, which appear to regulate multiple components of the interactions between placental and maternal cells, called HLA class 1b genes. The HLA class 1b genes have few alleles, which makes them unlikely to be recognized as foreign by the maternal cells. The low polymorphic properties of these particular HLAs may aid trophoblasts in actively avoiding immune attacks. This review gives a complete description of the mechanisms of interaction between HLAs and maternal uNK cells in humans.
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