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  1. Article: Neutralization and beyond: Antibodies and HIV-1 acquisition.

    Thomas, Allison S / Ghulam-Smith, Melissa / Sagar, Manish

    Current Topics In Virology

    2019  Volume 15, Page(s) 73–86

    Abstract: It is widely accepted that an effective HIV-1 preventative vaccine must elicit antibodies that can block virus acquisition. Although, anti-HIV-1 broadly neutralizing antibodies (bnAbs) have been isolated, unfortunately, no vaccine immunogens have been ... ...

    Abstract It is widely accepted that an effective HIV-1 preventative vaccine must elicit antibodies that can block virus acquisition. Although, anti-HIV-1 broadly neutralizing antibodies (bnAbs) have been isolated, unfortunately, no vaccine immunogens have been designed that can elicit these bnAbs in uninfected at-risk individuals. Some studies have suggested that other antibody functionalities, besides neutralization, such as antibody-dependent cellular cytotoxicity (ADCC), may prevent HIV-1 acquisition. In contrast to bnAbs, ADCC-inducing antibodies may be more amenable to elicitation by current vaccine technologies. This review will provide clarity about the role of nAbs and ADCC-inducing antibodies in preventing transmission, highlight mechanisms that potentially explain how ADCC-mediating antibodies may work, and speculate about the generation of these novel protective antibodies. Anti-HIV-1 ADCC-inducing antibodies may provide a new avenue for developing an effective HIV-1 vaccine.
    Language English
    Publishing date 2019-11-30
    Publishing country India
    Document type Journal Article
    ZDB-ID 2475042-6
    ISSN 0972-4591
    ISSN 0972-4591
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Developmental and behavioral phenotypes of pediatric patients with PTEN hamartoma tumor syndrome.

    MacFarland, Suzanne P / Duvall, Melani / Kemajou, Raissa Tchetcho / Baldino, Sarah E / Zelley, Kristin / Black, Chelsea / Thomas, Allison / Thomas, Nina H / Ruffner, Melanie / Li, Yimei / Miller, Judith S / Brodeur, Garrett M / Shabason, Emily

    American journal of medical genetics. Part A

    2024  , Page(s) e63608

    Abstract: Our study characterized the neurodevelopmental spectrum of individuals with PTEN Hamartoma Tumor Syndrome (PHTS), a syndrome that predisposes to both neurodevelopmental phenotypes and cancer risk. We aim to better understand life-impacting ... ...

    Abstract Our study characterized the neurodevelopmental spectrum of individuals with PTEN Hamartoma Tumor Syndrome (PHTS), a syndrome that predisposes to both neurodevelopmental phenotypes and cancer risk. We aim to better understand life-impacting neurodevelopmental features of PHTS. Our study recruited 20 children/adolescents with PHTS, who were then administered assessments for autism spectrum disorder (ASD) and other neurocognitive measures, including assessment of IQ, executive and adaptive functioning, and health-related quality of life. Thirteen individuals (65%) were identified as having ASD, of which five were newly diagnosed during the study. Of those, ASD symptom severity was in the mild-moderate range for 77%. Overall, IQ was in the average range, with a mean of 92.61 (SD 24.45, p = 0.5), though there was a non-statistically significant trend toward individuals without ASD having a higher mean IQ (102.7 vs 82.3; p = 0.1). Subjects had significant impairment in processing speed (mean 75.38, SD 24.75, p < 0.05), decreased adaptive functioning skills across all domains, and a trend toward having more executive functioning problems. Individuals with PHTS are at increased risk of neurodevelopmental disorders, including ASD and impaired executive and adaptive functioning. Although clear guidelines exist for cancer surveillance for individuals with PHTS, additional guidelines and screening for neurodevelopmental disorders are warranted.
    Language English
    Publishing date 2024-03-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2108614-X
    ISSN 1552-4833 ; 0148-7299 ; 1552-4825
    ISSN (online) 1552-4833
    ISSN 0148-7299 ; 1552-4825
    DOI 10.1002/ajmg.a.63608
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Antibody-dependent cellular cytotoxicity responses and susceptibility influence HIV-1 mother-to-child transmission.

    Thomas, Allison S / Coote, Carolyn / Moreau, Yvetane / Isaac, John E / Ewing, Alexander C / Kourtis, Athena P / Sagar, Manish

    JCI insight

    2022  Volume 7, Issue 9

    Abstract: HIV-1 vaccine efforts are primarily directed toward eliciting neutralizing antibodies (nAbs). However, vaccine trials and mother-to-child natural history cohort investigations indicate that antibody-dependent cellular cytotoxicity (ADCC), not nAbs, ... ...

    Abstract HIV-1 vaccine efforts are primarily directed toward eliciting neutralizing antibodies (nAbs). However, vaccine trials and mother-to-child natural history cohort investigations indicate that antibody-dependent cellular cytotoxicity (ADCC), not nAbs, correlate with prevention. The ADCC characteristics associated with lack of HIV-1 acquisition remain unclear. Here, we examine ADCC and nAb properties in pretransmission plasma from HIV-1-exposed infants and from the corresponding transmitting and nontransmitting mothers' breast milk and plasma. Breadth and potency (BP) were assessed against a panel of heterologous, nonmaternal variants. ADCC and neutralization sensitivity were estimated for the strains in the infected mothers. Infants who eventually acquired HIV-1 and those who remained uninfected had similar pretransmission ADCCBP. Viruses circulating in the transmitting and nontransmitting mothers had similar ADCC susceptibility. Infants with higher pretransmission ADCCBP and exposure to more ADCC-susceptible strains were less likely to acquire HIV-1. In contrast, higher preexisting infant neutralization BP and greater maternal virus neutralization sensitivity did not associate with transmission. Infants had higher ADCCBP closer to birth and in the presence of high plasma IgG relative to IgA levels. Mothers with potent humoral responses against their autologous viruses harbored more ADCC-sensitive strains. ADCC sensitivity of the exposure variants and preexisting ADCCBP influenced mother-to-child HIV-1 transmission during breastfeeding. Vaccination strategies that enhance ADCC are likely insufficient to prevent HIV-1 transmission because some strains may have low ADCC susceptibility.
    MeSH term(s) Antibodies, Neutralizing ; Antibody-Dependent Cell Cytotoxicity ; Female ; HIV Antibodies ; HIV Infections/complications ; HIV-1 ; Humans ; Infant ; Infectious Disease Transmission, Vertical/prevention & control ; Milk, Human
    Chemical Substances Antibodies, Neutralizing ; HIV Antibodies
    Language English
    Publishing date 2022-05-09
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 2379-3708
    ISSN (online) 2379-3708
    DOI 10.1172/jci.insight.159435
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: A new cell line for assessing HIV-1 antibody dependent cellular cytotoxicity against a broad range of variants

    Thomas, Allison S / Ghulam-Smith, Melissa / Olson, Alex / Coote, Carolyn / Gonzales, Oscar / Sagar, Manish

    Journal of immunological methods. 2020 May, v. 480

    2020  

    Abstract: Human immunodeficiency virus type 1 (HIV-1) studies suggest that antibody-dependent cellular cytotoxicity (ADCC) influences both virus acquisition and subsequent disease outcome. Technical issues with currently available assays, however, have limited the ...

    Abstract Human immunodeficiency virus type 1 (HIV-1) studies suggest that antibody-dependent cellular cytotoxicity (ADCC) influences both virus acquisition and subsequent disease outcome. Technical issues with currently available assays, however, have limited the ability to comprehensively assess the impact of ADCC on transmission and disease progression. Commonly used ADCC assays use a target cell line, CEM.NKr-CCR5-Luc, that often does not support replication of relevant HIV-1 variants. Thus, the extent of ADCC responses against a large panel of HIV-1 strains often cannot be assessed using the currently available methods. We developed two new reporter cell-lines (MT4-CCR5-Luc and PM1-CCR5-Luc) to overcome these issues. MT4-CCR5-Luc cells are resistant, whereas PM1-CCR5-Luc cells are susceptible, to killing by a natural killer cell line, CD16+KHYG-1, in the absence of antibody. Polyclonal HIVIG gave similar ADCC estimates against HIV-1 isolate, NL4-3, regardless of which of the three cell lines were used as the targets. In contrast to CEM.NKr-CCR5-Luc and PM1-CCR5-Luc, however, MT4-CCR5-Luc target cells produce significantly higher luciferase after exposure to various HIV-1 strains, including transmitted founder variants and viruses incorporating specific envelopes of interest. This higher luciferase expression does not yield spurious results because ADCC estimates are similar when killing is assessed by both reporter protein expression and flow cytometry. Furthermore, ADCC estimates derived from MT4-CCR5-Luc cells are not skewed by non-antibody contents present in human plasma. In aggregate, the MT4-CCR5-Luc cell line can be used to estimate monoclonal antibody or plasma-induced ADCC responses against a diverse range of HIV-1 envelopes relevant for transmission and disease progression studies.
    Keywords Human immunodeficiency virus 1 ; cell lines ; cytotoxicity ; disease progression ; flow cytometry ; humans ; luciferase ; monoclonal antibodies ; natural killer cells ; protein synthesis ; viruses
    Language English
    Dates of publication 2020-05
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 120142-6
    ISSN 1872-7905 ; 0022-1759
    ISSN (online) 1872-7905
    ISSN 0022-1759
    DOI 10.1016/j.jim.2020.112766
    Database NAL-Catalogue (AGRICOLA)

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  5. Article ; Online: A new cell line for assessing HIV-1 antibody dependent cellular cytotoxicity against a broad range of variants.

    Thomas, Allison S / Ghulam-Smith, Melissa / Olson, Alex / Coote, Carolyn / Gonzales, Oscar / Sagar, Manish

    Journal of immunological methods

    2020  Volume 480, Page(s) 112766

    Abstract: Human immunodeficiency virus type 1 (HIV-1) studies suggest that antibody-dependent cellular cytotoxicity (ADCC) influences both virus acquisition and subsequent disease outcome. Technical issues with currently available assays, however, have limited the ...

    Abstract Human immunodeficiency virus type 1 (HIV-1) studies suggest that antibody-dependent cellular cytotoxicity (ADCC) influences both virus acquisition and subsequent disease outcome. Technical issues with currently available assays, however, have limited the ability to comprehensively assess the impact of ADCC on transmission and disease progression. Commonly used ADCC assays use a target cell line, CEM.NKr-CCR5-Luc, that often does not support replication of relevant HIV-1 variants. Thus, the extent of ADCC responses against a large panel of HIV-1 strains often cannot be assessed using the currently available methods. We developed two new reporter cell-lines (MT4-CCR5-Luc and PM1-CCR5-Luc) to overcome these issues. MT4-CCR5-Luc cells are resistant, whereas PM1-CCR5-Luc cells are susceptible, to killing by a natural killer cell line, CD16
    MeSH term(s) Antibody-Dependent Cell Cytotoxicity ; Cell Line ; Coculture Techniques ; Genes, Reporter ; HIV Antibodies/immunology ; HIV Antigens/immunology ; HIV Infections/immunology ; HIV Infections/pathology ; HIV Infections/virology ; HIV-1/immunology ; HIV-1/pathogenicity ; Host-Pathogen Interactions ; Humans ; Killer Cells, Natural/immunology ; Killer Cells, Natural/virology ; Luciferases/biosynthesis ; Luciferases/genetics ; Lymphocytes/immunology ; Lymphocytes/virology ; env Gene Products, Human Immunodeficiency Virus/immunology
    Chemical Substances HIV Antibodies ; HIV Antigens ; env Gene Products, Human Immunodeficiency Virus ; Luciferases (EC 1.13.12.-)
    Language English
    Publishing date 2020-03-02
    Publishing country Netherlands
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 120142-6
    ISSN 1872-7905 ; 0022-1759
    ISSN (online) 1872-7905
    ISSN 0022-1759
    DOI 10.1016/j.jim.2020.112766
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Book: DNA damage repair

    Thomas, Allison E

    repair mechanisms, and aging

    (DNA : properties and modifications, functions and interactions, recombination and applications)

    2010  

    Author's details Allison E. Thomas, editor
    Series title DNA : properties and modifications, functions and interactions, recombination and applications
    MeSH term(s) DNA Repair ; DNA Damage ; Aging/physiology
    Language English
    Size xiii, 288 p. :, ill.
    Publisher Nova Science Publishers
    Publishing place New York
    Document type Book
    ISBN 9781616689148 ; 1616689145
    Database Catalogue of the US National Library of Medicine (NLM)

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  7. Article ; Online: Pre-existing infant antibody-dependent cellular cytotoxicity associates with reduced HIV-1 acquisition and lower morbidity.

    Thomas, Allison S / Moreau, Yvetane / Jiang, Wenqing / Isaac, John E / Ewing, Alexander / White, Laura F / Kourtis, Athena P / Sagar, Manish

    Cell reports. Medicine

    2021  Volume 2, Issue 10, Page(s) 100412

    Abstract: In humans, pre-existing anti-HIV-1 neutralizing antibodies (nAbs) have not been associated with decreased HIV-1 acquisition. Here, we evaluate antibody-dependent cellular cytotoxicity (ADCC) present in pre-transmission infant and maternal plasma and ... ...

    Abstract In humans, pre-existing anti-HIV-1 neutralizing antibodies (nAbs) have not been associated with decreased HIV-1 acquisition. Here, we evaluate antibody-dependent cellular cytotoxicity (ADCC) present in pre-transmission infant and maternal plasma and breast milk (BM) against the contemporaneous maternal HIV-1 variants. HIV-1-exposed uninfected compared with HIV-1-exposed infected infants have higher ADCC and a combination of ADCC and nAb responses against their corresponding mother's strains. ADCC does not correlate with nAbs, suggesting they are independent activities. The infected infants with high ADCC compared with low ADCC, but not those with higher ADCC plus nAbs, have lower morbidity up to 1 year after birth. A higher IgA to IgG ratio, observed in BM supernatants and in a higher proportion of the infected compared with the uninfected infants, associates with lower ADCC. Against the exposure strains, ADCC, more than nAbs, associates with both lower mother-to-child transmission and decreased post-infection infant morbidity.
    MeSH term(s) Adult ; Antibodies, Neutralizing/blood ; Antibody-Dependent Cell Cytotoxicity ; Cytotoxicity, Immunologic ; Female ; HIV Antibodies/blood ; HIV Infections/genetics ; HIV Infections/immunology ; HIV Infections/pathology ; HIV Infections/virology ; HIV-1/genetics ; HIV-1/immunology ; HIV-1/pathogenicity ; Humans ; Immune Sera/chemistry ; Immunoglobulin A/blood ; Immunoglobulin G/blood ; Infant ; Infectious Disease Transmission, Vertical ; Milk, Human/chemistry ; Milk, Human/immunology ; Pregnancy
    Chemical Substances Antibodies, Neutralizing ; HIV Antibodies ; Immune Sera ; Immunoglobulin A ; Immunoglobulin G
    Language English
    Publishing date 2021-10-19
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ISSN 2666-3791
    ISSN (online) 2666-3791
    DOI 10.1016/j.xcrm.2021.100412
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Correction: Characterizing the neurological phenotype of the hyperinsulinism hyperammonemia syndrome.

    Rosenfeld, Elizabeth / Nanga, Ravi Prakash Reddy / Lucas, Alfredo / Revell, Andrew Y / Thomas, Allison / Thomas, Nina H / Roalf, David R / Shinohara, Russell T / Reddy, Ravinder / Davis, Kathryn A / De León, Diva D

    Orphanet journal of rare diseases

    2022  Volume 17, Issue 1, Page(s) 315

    Language English
    Publishing date 2022-08-18
    Publishing country England
    Document type Published Erratum
    ZDB-ID 2225857-7
    ISSN 1750-1172 ; 1750-1172
    ISSN (online) 1750-1172
    ISSN 1750-1172
    DOI 10.1186/s13023-022-02466-8
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Characterizing the neurological phenotype of the hyperinsulinism hyperammonemia syndrome.

    Rosenfeld, Elizabeth / Nanga, Ravi Prakash Reddy / Lucas, Alfredo / Revell, Andrew Y / Thomas, Allison / Thomas, Nina H / Roalf, David R / Shinohara, Russell T / Reddy, Ravinder / Davis, Kathryn A / De León, Diva D

    Orphanet journal of rare diseases

    2022  Volume 17, Issue 1, Page(s) 248

    Abstract: Background: Hyperinsulinism hyperammonemia (HI/HA) syndrome is caused by activating mutations in GLUD1, encoding glutamate dehydrogenase (GDH). Atypical absence seizures and neuropsychological disorders occur at high rates in this form of ... ...

    Abstract Background: Hyperinsulinism hyperammonemia (HI/HA) syndrome is caused by activating mutations in GLUD1, encoding glutamate dehydrogenase (GDH). Atypical absence seizures and neuropsychological disorders occur at high rates in this form of hyperinsulinism. Dysregulated central nervous system (CNS) glutamate balance, due to GDH overactivity in the brain, has been hypothesized to play a role. This study aimed to describe the neurologic phenotype in HI/HA syndrome and investigate CNS glutamate levels using glutamate weighted chemical exchange saturation transfer magnetic resonance imaging (GluCEST MRI). In this cross-sectional study, 12 subjects with HI/HA syndrome had plasma ammonia measurement, self- or parent-completed neurocognitive assessments, electroencephalogram (EEG), and GluCEST MRI at 7 T performed. GluCEST MRI measures were compared to a historic reference population of 10 healthy adults.
    Results: Subjects were five males and seven females with median age of 25.5 years. Seventy-five percent of subjects reported a history of neurodevelopmental problems and 42% had neurocognitive assessment scores outside the normal range. Fifty percent had interictal EEG findings of generalized, irregular spike and wave discharges. Higher variability in hippocampal GluCEST asymmetry (p = 0.002), and in peak hippocampal GluCEST values (p = 0.008), was observed in HI/HA subjects (n = 9 with interpretable MRI) compared to the healthy reference population (n = 10).
    Conclusions: The high prevalence of abnormal neurocognitive assessment scores and interictal EEG findings observed highlights the importance of longitudinal neuropsychological assessment for individuals with HI/HA syndrome. Our findings demonstrate the potential application of GluCEST to investigate persistent knowledge gaps in the mechanisms underlying the unique neurophenotype of this disorder.
    MeSH term(s) Cross-Sectional Studies ; Female ; Glutamate Dehydrogenase/genetics ; Glutamates ; Humans ; Hyperammonemia/genetics ; Hyperinsulinism/genetics ; Hypoglycemia ; Male ; Phenotype
    Chemical Substances Glutamates ; Glutamate Dehydrogenase (EC 1.4.1.2)
    Language English
    Publishing date 2022-06-25
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2225857-7
    ISSN 1750-1172 ; 1750-1172
    ISSN (online) 1750-1172
    ISSN 1750-1172
    DOI 10.1186/s13023-022-02398-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Vertical HIV-1 Transmission in the Setting of Maternal Broad and Potent Antibody Responses.

    Tu, Joshua J / Kumar, Amit / Giorgi, Elena E / Eudailey, Joshua / LaBranche, Celia C / Martinez, David R / Fouda, Genevieve G / Moreau, Yvetane / Thomas, Allison / Montefiori, David / Gao, Feng / Sagar, Manish / Permar, Sallie R

    Journal of virology

    2022  Volume 96, Issue 11, Page(s) e0023122

    Abstract: Despite the worldwide availability of antiretroviral therapy (ART), approximately 150,000 pediatric HIV infections continue to occur annually. ART can dramatically reduce HIV mother-to-child transmission (MTCT), but inconsistent drug access and adherence, ...

    Abstract Despite the worldwide availability of antiretroviral therapy (ART), approximately 150,000 pediatric HIV infections continue to occur annually. ART can dramatically reduce HIV mother-to-child transmission (MTCT), but inconsistent drug access and adherence, as well as primary maternal HIV infection during pregnancy and lactation are major barriers to eliminating vertical HIV transmission. Thus, immunologic strategies to prevent MTCT, such as an HIV vaccine, will be required to attain an HIV-free generation. A primary goal of HIV vaccine research has been to elicit broadly neutralizing antibodies (bnAbs) given the ability of passive bnAb immunization to protect against sensitive strains, yet we previously observed that HIV-transmitting mothers have more plasma neutralization breadth than nontransmitting mothers. Additionally, we have identified infant transmitted/founder (T/F) viruses that escape maternal bnAb responses. In this study, we examine a cohort of postpartum HIV-transmitting women with neutralization breadth to determine if certain maternal bnAb specificities drive the selection of infant T/F viruses. Using HIV pseudoviruses that are resistant to neutralizing antibodies targeting common bnAb epitopes, we mapped the plasma bnAb specificities of this cohort. Significantly more transmitting women with plasma bnAb activity had a mappable plasma bnAb specificity (six of seven, or 85.7%) compared to that of nontransmitting women with plasma bnAb activity (7 of 21, or 33.3%,
    MeSH term(s) AIDS Vaccines ; Antibody Formation ; Broadly Neutralizing Antibodies ; Epitopes ; Female ; HIV Antibodies/immunology ; HIV Infections/transmission ; HIV Seropositivity ; HIV-1 ; Humans ; Infant ; Infectious Disease Transmission, Vertical/prevention & control ; Pregnancy
    Chemical Substances AIDS Vaccines ; Broadly Neutralizing Antibodies ; Epitopes ; HIV Antibodies
    Language English
    Publishing date 2022-05-10
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.00231-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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