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Cotton MF, Madhi SA, Luabeya AK, Tameris M, Hesseling AC, Shenje J, Schoeman E, Hatherill M, Desai S, Kapse D, Brückner S, Koen A, Jose L, Moultrie A, Bhikha S, Walzl G, Gutschmidt A, Kotze LA, Allies DL, Loxton AG, Shaligram U, Abraham M, Johnstone H, Grode L, Kaufmann SHE, Kulkarni PS. Safety and immunogenicity of VPM1002 versus BCG in South African newborn babies: a randomised, phase 2 non-inferiority double-blind controlled trial. THE LANCET INFECTIOUS DISEASES 2022; 22:1472-1483. [DOI: 10.1016/s1473-3099(22)00222-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 02/16/2022] [Accepted: 03/23/2022] [Indexed: 12/13/2022]
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2
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Ikumi NM, Pillay K, Tilburgs T, Malaba TR, Dzanibe S, Enninga EAL, Chakraborty R, Lamorde M, Myer L, Khoo S, Jaspan HB, Gray CM. T cell Homeostatic Imbalance in Placentae from Women with HIV in the absence of Vertical Transmission. J Infect Dis 2021; 224:S670-S682. [PMID: 33880544 DOI: 10.1093/infdis/jiab192] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Implementation of universal antiretroviral therapy (ART) has significantly lowered vertical transmission rates but has also increased numbers of HIV-exposed uninfected children (HEU), who remain vulnerable to morbidities. Here, we investigated whether T cell alterations in the placenta contribute to altered immune status in HEU. METHODS We analyzed T cells from term placentae decidua and villous tissue and paired cord blood from pregnant women with HIV (PWH) who initiated ART late in pregnancy (n=21) with pregnant women not living with HIV (PWNH) (n=9). RESULTS Placentae from PWH showed inverted CD4:CD8 ratios and higher proportions of tissue resident CD8+ T cells in villous tissue relative to control placentae. CD8+ T cells in the fetal capillaries, which were of fetal origin, positively correlated with maternal plasma viraemia prior to ART initiation, implying that imbalanced T cells persisted throughout pregnancy. Additionally, the expanded memory differentiation of CD8+ T cells was confined to the fetal placental compartment and cord blood but was not observed in the maternal decidua. CONCLUSIONS T cell homeostatic imbalance in the blood circulation of PWH is reflected in the placenta. The placenta may be a causal link between HIV-induced maternal immune changes during gestation and altered immunity in newborn infants in the absence of vertical transmission.
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Affiliation(s)
- Nadia M Ikumi
- Division of Immunology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
| | - Komala Pillay
- National Health Laboratory Services, Groote Schuur Hospital, Cape Town, South Africa.,Division of Anatomical Pathology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Tamara Tilburgs
- Division of Immunobiology, Center for Inflammation and Tolerance, Cincinnati Children's Hospital, Cincinnati OH 45229, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati OH 45229, USA
| | - Thokozile R Malaba
- Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Sonwabile Dzanibe
- Division of Immunology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
| | | | - Rana Chakraborty
- Department of Obstetrics and Gynecology, Mayo Clinic, Rochester, MN.,Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine and Science, Minnesota, USA.,Department of Immunology, Mayo Clinic, Rochester, MN
| | - Mohammed Lamorde
- Infectious Diseases Institute, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Landon Myer
- Division of Epidemiology and Biostatistics, School of Public Health and Family Medicine, University of Cape Town, Cape Town, South Africa
| | - Saye Khoo
- Molecular and Clinical Pharmacology, University of Liverpool, Liverpool, UK.,Royal Liverpool and Broadgreen University Hospitals NHS Trust, Liverpool, UK
| | - Heather B Jaspan
- Division of Immunology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa
| | - Clive M Gray
- Division of Immunology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, South Africa.,National Health Laboratory Services, Groote Schuur Hospital, Cape Town, South Africa.,Department of Pathology, University of Cape Town, Cape Town, South Africa
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3
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Kohli J, Veenstra I, Demaria M. The struggle of a good friend getting old: cellular senescence in viral responses and therapy. EMBO Rep 2021; 22:e52243. [PMID: 33734564 PMCID: PMC8024996 DOI: 10.15252/embr.202052243] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/11/2021] [Accepted: 03/01/2021] [Indexed: 12/15/2022] Open
Abstract
Cellular senescence is a state of stable cell cycle arrest associated with macromolecular alterations and secretion of pro-inflammatory cytokines and molecules. Senescence-associated phenotypes restrict damage propagation and activate immune responses, two essential processes involved in response to viral infections. However, excessive accumulation and persistence of senescent cells can become detrimental and promote pathology and dysfunctions. Various pharmacological interventions, including antiviral therapies, lead to aberrant and premature senescence. Here, we review the molecular mechanisms by which viral infections and antiviral therapy induce senescence. We highlight the importance of these processes in attenuating viral dissemination and damage propagation, but also how prematurely induced senescent cells can promote detrimental adverse effects in humans. We describe which sequelae due to viral infections and treatment can be partly due to excessive and aberrant senescence. Finally, we propose that pharmacological strategies which eliminate senescent cells or suppress their secretory phenotype could mitigate side effects and alleviate the onset of additional morbidities. These strategies can become extremely beneficial in patients recovering from viral infections or undergoing antiviral therapy.
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Affiliation(s)
- Jaskaren Kohli
- European Research Institute for the Biology of Ageing (ERIBA)University Medical Center Groningen (UMCG)GroningenThe Netherlands
| | - Iris Veenstra
- European Research Institute for the Biology of Ageing (ERIBA)University Medical Center Groningen (UMCG)GroningenThe Netherlands
| | - Marco Demaria
- European Research Institute for the Biology of Ageing (ERIBA)University Medical Center Groningen (UMCG)GroningenThe Netherlands
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Chiappini E, Larotonda F, Lisi C, Giacomet V, Erba P, Bernardi S, Zangari P, Di Biagio A, Taramasso L, Giaquinto C, Rampon O, Gabiano C, Garazzino S, Tagliabue C, Esposito S, Bruzzese E, Badolato R, Zanaboni D, Cellini M, Dedoni M, Mazza A, Pession A, Giannini AM, Salvini F, Dodi I, Carloni I, Cazzato S, Tovo PA, de Martino M, Galli L. Real-World Analysis of Survival and Clinical Events in a Cohort of Italian Perinatally HIV-1 Infected Children From 2001 to 2018. Front Pediatr 2021; 9:665764. [PMID: 34336735 PMCID: PMC8322739 DOI: 10.3389/fped.2021.665764] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 06/15/2021] [Indexed: 11/13/2022] Open
Abstract
Background: Combined antiretroviral therapy (cART) has been associated with a steep decrease in mortality and morbidity in HIV-1 infected children. New antiretroviral molecules and drug classes have been developed and the management of HIV-infected children has improved, but recent data on survival are limited. Methods: An observational retrospective study investigating changes in mortality and morbidity was conducted on 1,091 perinatally HIV-1 infected children enrolled in the Italian Register for HIV Infection in Children and followed-up from 2001 to 2018. Results: Three hundred and fifty-four (32%) AIDS events and 26 (2%) deaths occurred overtime. Mortality rates decreased from 0.4/100 person-years in 2001-2006 to 0.27/100 person-years in 2007-2012 and 0.07/100 person-years in 2013-2018. Notably, 92% of the dead children were born in Italy, but only 50% were followed-up since birth or within three months of age. Seventy three percent of children had started cART at age ≥6 months; 23% were treated for <30 days before death. B and C clinical events progressively decreased (P < 0.0001). Opportunistic infections significantly decreased over time, but still were the most common events in all the periods (6.76/100 person-years in 2013-2018). In the last period, severe bacterial infections were the most common ones. Cancer rates were 0.07/100; 0.17/100; 0.07/100 person-years in the three periods, respectively. Conclusions: Progressive reductions both in mortality and in rates of class B and C clinical events and OIs have been observed during the cART era. However, deaths were still registered; more than half of dead children were enrolled after birth and had belatedly started cART.
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Affiliation(s)
- Elena Chiappini
- Paediatric Infectious Diseases Unit, Department of Health Sciences, Anna Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Paediatric Medicine, Anna Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Francesca Larotonda
- Paediatric Infectious Diseases Unit, Department of Health Sciences, Anna Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Paediatric Medicine, Anna Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Catiuscia Lisi
- Paediatric Infectious Diseases Unit, Department of Health Sciences, Anna Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Paediatric Medicine, Anna Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Vania Giacomet
- Paediatric Infectious Diseases Unit, Department of Paediatrics, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Paola Erba
- Paediatric Infectious Diseases Unit, Department of Paediatrics, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Stefania Bernardi
- Unit of Immune and Infectious Diseases, Stefania Bernardi Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Paola Zangari
- Research Unit of Clinical Immunology and Vaccinology, Paola Zangari Academic Department of Pediatrics (DPUO), Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Antonio Di Biagio
- Infectious Diseases Unit, Policlinico San Martino Hospital, University of Genova, Genoa, Italy
| | - Lucia Taramasso
- Infectious Diseases Unit, Policlinico San Martino Hospital, University of Genova, Genoa, Italy
| | - Carlo Giaquinto
- Department of Women and Child Health, University of Padova, Padua, Italy
| | - Osvalda Rampon
- Department of Women and Child Health, University of Padova, Padua, Italy
| | - Clara Gabiano
- Paediatric Infectious Diseases Unit, Regina Margherita Children's Hospital, University of Turin, Turin, Italy
| | - Silvia Garazzino
- Paediatric Infectious Diseases Unit, Regina Margherita Children's Hospital, University of Turin, Turin, Italy
| | - Claudia Tagliabue
- Paediatric Highly Intensive Care Unit, Department of Pathophysiology and Transplantation, Istituti di Ricovero e Cura a Carattere Scientifico Ca' Granda Ospedale Maggiore Policlinico Foundation, University of Milan, Milan, Italy
| | - Susanna Esposito
- Paediatric Department, Pietro Barilla Children's Hospital, University of Parma, Parma, Italy
| | - Eugenia Bruzzese
- Paediatric Unit, Department of Translational Medical Sciences, University of Naples Federico II, Naples, Italy
| | - Raffaele Badolato
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | - Domenico Zanaboni
- Department on Internal Medicine and Therapeutics, Istituti di Ricovero e Cura a Carattere Scientifico Policlinico "S. Matteo" Foundation, University of Pavia, Pavia, Italy
| | - Monica Cellini
- Paediatric Hemato-Oncology Unit, Department of Medical and Surgical Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Maurizio Dedoni
- Department of Paediatrics, Ospedale Microcitemico, Cagliari, Italy
| | - Antonio Mazza
- Department of Paediatrics, "S. Chiara" Hospital, Trento, Italy
| | - Andrea Pession
- Paediatric Unit, IRCCS Scientific Institute for Research and Healthcare, Sant'Orsola Hospital, Bologna, Italy
| | - Anna Maria Giannini
- Paediatric Infectious Diseases Unit, University Hospital Policlinico Giovanni XXIII, Bari, Italy
| | - Filippo Salvini
- Department of Paediatrics, Niguarda Hospital, University of Milan, Milan, Italy
| | - Icilio Dodi
- Department of Medicine and Surgery, Pietro Barilla Children's Hospital, University of Parma, Parma, Italy
| | - Ines Carloni
- Department of Mother and Child Health, Salesi Children's Hospital, Ancona, Italy
| | - Salvatore Cazzato
- Department of Mother and Child Health, Salesi Children's Hospital, Ancona, Italy
| | - Pier Angelo Tovo
- Paediatric Infectious Diseases Unit, Regina Margherita Children's Hospital, University of Turin, Turin, Italy
| | - Maurizio de Martino
- Paediatric Infectious Diseases Unit, Department of Health Sciences, Anna Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Paediatric Medicine, Anna Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Luisa Galli
- Paediatric Infectious Diseases Unit, Department of Health Sciences, Anna Meyer Children's Hospital, University of Florence, Florence, Italy.,Department of Paediatric Medicine, Anna Meyer Children's Hospital, University of Florence, Florence, Italy
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5
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Dalzini A, Petrara MR, Ballin G, Zanchetta M, Giaquinto C, De Rossi A. Biological Aging and Immune Senescence in Children with Perinatally Acquired HIV. J Immunol Res 2020; 2020:8041616. [PMID: 32509884 PMCID: PMC7246406 DOI: 10.1155/2020/8041616] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022] Open
Abstract
Chronic HIV-infected children suffer from premature aging and aging-related diseases. Viral replication induces an ongoing inflammation process, with the release of pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), the activation of the immune system, and the production of proinflammatory cytokines. Although combined highly active antiretroviral therapy (ART) has significantly modified the natural course of HIV infection, normalization of T and B cell phenotype is not completely achievable; thus, many HIV-infected children display several phenotypical alterations, including higher percentages of activated cells, that favor an accelerated telomere attrition, and higher percentages of exhausted and senescent cells. All these features ultimately lead to the clinical manifestations related to premature aging and comorbidities typically observed in older general population, including non-AIDS-related malignancies. Therefore, even under effective treatment, the premature aging process of HIV-infected children negatively impacts their quality and length of life. This review examines the available data on the impact of HIV and ART on immune and biological senescence of HIV-infected children.
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Affiliation(s)
- Annalisa Dalzini
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Maria Raffaella Petrara
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Giovanni Ballin
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | | | - Carlo Giaquinto
- Department of Mother and Child Health, University of Padova, Padova, Italy
| | - Anita De Rossi
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of Viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
- Veneto Institute of Oncology IOV – IRCCS, Padua, Italy
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6
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Chiappini E, Bianconi M, Dalzini A, Petrara MR, Galli L, Giaquinto C, De Rossi A. Accelerated aging in perinatally HIV-infected children: clinical manifestations and pathogenetic mechanisms. Aging (Albany NY) 2019; 10:3610-3625. [PMID: 30418933 PMCID: PMC6286860 DOI: 10.18632/aging.101622] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 10/27/2018] [Indexed: 12/12/2022]
Abstract
Background: Premature aging and related diseases have been documented in HIV-infected adults. Data are now emerging also regarding accelerated aging process in HIV-infected children. Methods: A narrative review was performed searching studies on PubMed published in English language in 2004-2017, using appropriate key words, including “aging”, “children”, “HIV”, “AIDS”, “immunosenescence”, “pathogenesis”, “clinical conditions”. Results: Premature immunosenescence phenotype of B and T cells in HIV-infected children is mediated through immune system activation and chronic inflammation. Ongoing inflammation processes have been documented by increased levels of pathogen-associated molecular patterns (PAMPS), increased mitochondrial damage, higher levels of pro-inflammatory cytokines, and a positive correlation between sCD14 levels and percentages of activated CD8+ cells. Other reported features of premature aging include cellular replicative senescence, linked to an accelerated telomeres shortening. Finally, acceleration of age-associated methylation pattern and other epigenetic modifications have been described in HIV-infected children. All these features may favor the clinical manifestations related to premature aging. Lipid and bone metabolism, cancers, cardiovascular, renal, and neurological systems should be carefully monitored, particularly in children with detectable viremia and/or with CD4/CD8 ratio inversion. Conclusion: Aging processes in children with HIV infection impact their quality and length of life. Further studies regarding the mechanisms involved in premature aging are needed to search for potential targets of treatment.
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Affiliation(s)
- Elena Chiappini
- Infectious Disease Unit, Meyer Children's Hospital, Department of Science Health, University of Florence, Florence, Italy
| | - Martina Bianconi
- Infectious Disease Unit, Meyer Children's Hospital, Department of Science Health, University of Florence, Florence, Italy
| | - Annalisa Dalzini
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Maria Raffaella Petrara
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy
| | - Luisa Galli
- Infectious Disease Unit, Meyer Children's Hospital, Department of Science Health, University of Florence, Florence, Italy
| | - Carlo Giaquinto
- Department of Mother and Child Health, University of Padova, Padova, Italy
| | - Anita De Rossi
- Section of Oncology and Immunology, Department of Surgery, Oncology and Gastroenterology, Unit of viral Oncology and AIDS Reference Center, University of Padova, Padova, Italy.,Istituto Oncologico Veneto IOV-IRCCS, Padova, Italy
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Immune Activation, Inflammation, and Non-AIDS Co-Morbidities in HIV-Infected Patients under Long-Term ART. Viruses 2019; 11:v11030200. [PMID: 30818749 PMCID: PMC6466530 DOI: 10.3390/v11030200] [Citation(s) in RCA: 254] [Impact Index Per Article: 50.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/19/2019] [Accepted: 02/26/2019] [Indexed: 02/07/2023] Open
Abstract
Despite effective antiretroviral therapy (ART), people living with HIV (PLWH) still present persistent chronic immune activation and inflammation. This condition is the result of several factors including thymic dysfunction, persistent antigen stimulation due to low residual viremia, microbial translocation and dysbiosis, caused by the disruption of the gut mucosa, co-infections, and cumulative ART toxicity. All of these factors can create a vicious cycle that does not allow the full control of immune activation and inflammation, leading to an increased risk of developing non-AIDS co-morbidities such as metabolic syndrome and cardiovascular diseases. This review aims to provide an overview of the most recent data about HIV-associated inflammation and chronic immune exhaustion in PLWH under effective ART. Furthermore, we discuss new therapy approaches that are currently being tested to reduce the risk of developing inflammation, ART toxicity, and non-AIDS co-morbidities.
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Garcia-Knight MA, Nduati E, Hassan AS, Nkumama I, Etyang TJ, Hajj NJ, Gambo F, Odera D, Berkley JA, Rowland-Jones SL, Urban B. Cytomegalovirus viraemia is associated with poor growth and T-cell activation with an increased burden in HIV-exposed uninfected infants. AIDS 2017; 31:1809-1818. [PMID: 28609400 PMCID: PMC5538302 DOI: 10.1097/qad.0000000000001568] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Objective: Factors associated with poor health in HIV-exposed-uninfected (HEU) infants are poorly defined. We describe the prevalence and correlates of cytomegalovirus (CMV) viraemia in HEU and HIV-unexposed-uninfected (HUU) infants, and quantify associations with anthropometric, haematological, and immunological outcomes. Design: Cross-sectional, including HEU and HUU infants from rural coastal Kenya. Methods: Infants aged 2–8 months were studied. The primary outcome was CMV viraemia and viral load, determined by quantitative PCR. Correlates were tested by logistic and linear regression; coefficients were used to describe associations between CMV viraemia and clinical/immunological parameters. Results: In total, 42 of 65 (64.6%) infants had CMV viraemia [median viral load, 3.0 (interquartile ranges: 2.7–3.5) log10 IU/ml]. Compared to community controls, HEU infants had six-fold increased odds of being viraemic (adjusted odds ratio 5.95 [95% confidence interval: 1.82–19.36], P = 0.003). Age, but not HEU/HUU status, was a strong correlate of CMV viral load (coefficient = −0.15, P = 0.009). CMV viral load associated negatively with weight-for-age (WAZ) Z-score (coefficient = −1.06, P = 0.008) and head circumference-for-age Z-score (coefficient = −1.47, P = 0.012) and positively with CD8+ T-cell coexpression of CD38/human leucocyte antigen DR (coefficient = 15.05, P = 0.003). Conclusion: The odds of having CMV viraemia was six-fold greater in HEU than HUU infants when adjusted for age. CMV viral load was associated with adverse growth and heightened CD8+ T-cell immune activation. Longitudinal assessments of the clinical effects of primary CMV infection and associated immunomodulation in early life in HEU and HUU populations are warranted.
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9
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Abstract
Supplemental Digital Content is available in the text Several pieces of evidence indicate that HIV-infected adults undergo premature aging. The effect of HIV and antiretroviral therapy (ART) exposure on the aging process of HIV-infected children may be more deleterious since their immune system coevolves from birth with HIV.
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Early ART Results in Greater Immune Reconstitution Benefits in HIV-Infected Infants: Working with Data Missingness in a Longitudinal Dataset. PLoS One 2015; 10:e0145320. [PMID: 26671450 PMCID: PMC4699458 DOI: 10.1371/journal.pone.0145320] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 12/02/2015] [Indexed: 11/19/2022] Open
Abstract
Background Early initiation of anti-retroviral treatment (ART) decreases mortality as compared to deferred treatment, but whether it preserves immune cells from early loss or promotes their recovery remains undefined. Determination of complex immunological endpoints in infants is often marred by missing data due to missed visits and/or inadequate sampling. Specialized methods are required to address missingness and facilitate data analysis. Methods We characterized the changes in cellular and humoral immune parameters over the first year of life in 66 HIV-infected infants (0–1 year of age) enrolled in the CHER study starting therapy within 12 weeks of birth (n = 42) or upon disease progression (n = 24). A convenience cohort of 23 uninfected infants aged 0–6 months born to mothers with HIV-1 infection was used as controls. Flow cytometry and ELISA were used to evaluate changes in natural killer (NK) cells, plasmacytoid dendritic cells (pDC), and CD4+ or CD8+ T-cell frequencies. Data missingness was assessed using Little's test. Complete datasets for analysis were created using Multiple Imputation (MI) or Bayesian modeling and multivariate analysis was conducted on the imputed datasets. Results HIV-1-infected infants had greater frequency of CD4+ T cells with naïve phenotype, as well as higher serum IL-7 levels than HIV exposed/uninfected infants. The elevated data missingness was completely at random, allowing the use of both MI and Bayesian modeling. Both methods indicate that early ART initiation results in higher CD4+ T cell frequency, lower expression of CD95 in CD8+ T cell, and preservation of naïve T cell subsets. In contrast, innate immune effectors appeared to be similar independently of the timing of ART initiation. Conclusions Early ART initiation in infants with perinatal HIV infection reduces immune activation and preserves an early expansion of naïve T-cells with undiminished innate cell numbers, giving greater immune reconstitution than achieved with deferred ART. Both statistical approaches concurred in this finding.
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11
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Gibson L, Barysauskas CM, McManus M, Dooley S, Lilleri D, Fisher D, Srivastava T, Diamond DJ, Luzuriaga K. Reduced frequencies of polyfunctional CMV-specific T cell responses in infants with congenital CMV infection. J Clin Immunol 2015; 35:289-301. [PMID: 25712611 PMCID: PMC4366322 DOI: 10.1007/s10875-015-0139-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Accepted: 02/04/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE CMV infection remains a priority for vaccine development. Vaccination of infants could modify congenital infection and provide lifetime immunity. Properties of CMV-specific T cells associated with control of viral replication in early life have not been fully defined. METHODS CMV-specific CD4 and CD8 T cell responses were investigated in infants with congenital CMV infection and compared to adults with primary or chronic infection. PBMC were stimulated with UL83 (pp65) or UL122 (IE-2) peptide pools then stained with antibodies to markers of T cell subset (CD4 or CD8), phenotype (CD45RA, CCR7), or function (MIP1β, CD107, IFNγ, IL2) for flow cytometry analysis. RESULTS Detection of CMV pp65-specific CD4 T cells was less common in infants than adults. Responder cells were primarily effector memory (EM, CD45RA-CCR7-) in adults, but mixed memory subsets in infants. Detection of CMV pp65-specific CD8 T cells did not differ between the groups, but infants had lower frequencies of total responding cells and of MIP1β- or CD107-expressing cells. Responder cells were EM or effector memory RA (CD45RA + CCR7-) in all groups. Polyfunctional T cells were less commonly detected in infants than adults. Responses to IE-2 were detected in adults but not infants. All infants had detectable circulating CMV DNA at initial study (versus 60 % of adults with primary infection) despite longer duration of CMV infection. CONCLUSIONS Reduced frequencies and altered functional profile of CMV-specific CD4 and CD8 T cell responses were detected in infants compared to adults, and were associated with persistent CMV DNA in peripheral blood.
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Affiliation(s)
- Laura Gibson
- Department of Medicine, University of Massachusetts Medical School, Worcester, MA, 01605, USA,
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12
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Hesseling AC, Jaspan HB, Black GF, Nene N, Walzl G. Immunogenicity of BCG in HIV-exposed and non-exposed infants following routine birth or delayed vaccination. Int J Tuberc Lung Dis 2015; 19:454-62. [PMID: 25860002 PMCID: PMC4530999 DOI: 10.5588/ijtld.14.0608] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Human immunodeficiency virus (HIV) exposed infants are at high risk of Mycobacterium tuberculosis exposure, have high rates of progression to tuberculosis (TB) disease and are at significant risk of bacille Calmette-Guérin (BCG) induced adverse events. OBJECTIVE To evaluate a delayed BCG vaccination strategy in HIV-exposed infants. DESIGN A randomised trial of routine BCG vaccination given at birth compared to 14 weeks of age in HIV-exposed non-infected and non-HIV-exposed infants to investigate longitudinal BCG-induced immune responses using a 7-day whole blood interferon-gamma (IFN-γ) enzyme-linked immunosorbent assay. RESULTS A significantly higher proportion of infants had positive responses to M. tuberculosis purified protein derivative (PPD) and BCG at 14 weeks in the birth vs. delayed vaccination groups (P = 0.001 for both). This difference was no longer apparent at weeks 24 or 52. Among infants vaccinated at birth, the 14-week IFN-γ response to M. tuberculosis PPD was lower among HIV-exposed than non-exposed infants (276.5 pg/ml vs. 790.2, P = 0.048). Among all infants, there were significant correlations between the magnitude of IFN-γ responses to BCG, M. tuberculosis PPD, TB 10.4 and culture filtrate protein 10/early secreted antigenic target 6. CONCLUSIONS The timing of vaccination had limited effect on BCG-induced IFN-γ responses, which waned considerably over 1 year despite initial vigorous responses in both vaccination groups. The lower responses in HIV-exposed non-infected infants suggest potentially altered mycobacterial immunity early in life.
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Affiliation(s)
- A C Hesseling
- Desmond Tutu TB Centre, Department of Paediatrics and Child Health, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - H B Jaspan
- Division of Immunology, Institute of Infectious Disease and Molecular Medicine, University of Cape Town Health Sciences Faculty, Cape Town, South Africa; Seattle Children's Research Institute, Seattle, Washington, USA
| | - G F Black
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research/Medical Research Council Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - N Nene
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research/Medical Research Council Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
| | - G Walzl
- Department of Science and Technology/National Research Foundation Centre of Excellence for Biomedical TB Research/Medical Research Council Centre for Molecular and Cellular Biology, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Tygerberg, South Africa
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de Deus N, Moraleda C, Serna-Bolea C, Renom M, Menendez C, Naniche D. Impact of elevated maternal HIV viral load at delivery on T-cell populations in HIV exposed uninfected infants in Mozambique. BMC Infect Dis 2015; 15:37. [PMID: 25645120 PMCID: PMC4320465 DOI: 10.1186/s12879-015-0766-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 01/15/2015] [Indexed: 11/10/2022] Open
Abstract
Background HIV-uninfected infants born to HIV-infected mothers (HIV-exposed uninfected, HEU) have been described to have immune alterations as compared to unexposed infants. This study sought to characterize T-cell populations after birth in HEU infants and unexposed infants living in a semirural area in southern Mozambique. Methods Between August 2008 and June 2009 mother-infant pairs were enrolled at the Manhiça District Hospital at delivery into a prospective observational analysis of immunological and health outcomes in HEU infants. Infants were invited to return at one month of age for a clinical examination, HIV DNA-PCR, and immunophenotypic analyses. The primary analysis sought to assess immunological differences between HEU and unexposed groups, whereas the secondary analysis assessed the impact of maternal HIV RNA viral load in the HEU group. Infants who had a positive HIV DNA-PCR test were not included in the analysis. Results At one month of age, the 74 HEU and the 56 unexposed infants had similar median levels of naïve, memory and activated CD8 and CD4 T-cells. Infant naïve and activated CD8 T-cells were found to be associated with maternal HIV-RNA load at delivery. HEU infants born to women with HIV-RNA loads above 5 log10 copies/mL had lower median levels of naïve CD8 T-cells (p = 0.04), and higher median levels of memory CD8 T-cells, (p = 0.014). Conclusions This study suggests that exposure to elevated maternal HIV-RNA puts the infant at higher risk of having early T-cell abnormalities. Improving prophylaxis of mother to child HIV programs such that more women have undetectable viral load is crucial to decrease vertical transmission of HIV, but may also be important to reduce the consequences of HIV virus exposure in HEU infants.
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Affiliation(s)
- Nilsa de Deus
- National Institute of Health, Maputo, Mozambique. .,Manhiça Health Research Centre (CISM), Manhiça, Mozambique.
| | - Cinta Moraleda
- Manhiça Health Research Centre (CISM), Manhiça, Mozambique. .,Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, C/Rossello 132, 4°, Barcelona, Spain.
| | - Celia Serna-Bolea
- Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, C/Rossello 132, 4°, Barcelona, Spain.
| | - Montse Renom
- Manhiça Health Research Centre (CISM), Manhiça, Mozambique. .,Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, C/Rossello 132, 4°, Barcelona, Spain.
| | - Clara Menendez
- Manhiça Health Research Centre (CISM), Manhiça, Mozambique. .,Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, C/Rossello 132, 4°, Barcelona, Spain.
| | - Denise Naniche
- Manhiça Health Research Centre (CISM), Manhiça, Mozambique. .,Barcelona Centre for International Health Research (CRESIB), Hospital Clinic, Universitat de Barcelona, C/Rossello 132, 4°, Barcelona, Spain.
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Pediatric Human Immunodeficiency Virus infection and cancer in the Highly Active Antiretroviral Treatment (HAART) era. Cancer Lett 2014; 347:38-45. [DOI: 10.1016/j.canlet.2014.02.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/13/2014] [Accepted: 02/03/2014] [Indexed: 12/18/2022]
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Thomas MR, Wara D, Saxton K, Truskier M, Chesney MA, Boyce WT. Family adversity and autonomic reactivity association with immune changes in HIV-affected school children. Psychosom Med 2013; 75:557-65. [PMID: 23766380 PMCID: PMC3830556 DOI: 10.1097/psy.0b013e31829807fb] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To explore whether primary school entry is associated with changes in immune system parameters in HIV-affected children. HIV-affected children are vulnerable to psychosocial stressors, regardless of their own HIV serological status. METHODS Data from 38 HIV-positive and 29 HIV-negative children born to seropositive women were obtained. Measures included family adversity questionnaires, autonomic nervous system (ANS) reactivity, and enumerative and functional changes in peripheral blood immune parameters. RESULTS In comparison with children who were HIV-negative, children who were HIV-positive at baseline had fewer CD4(+) T lymphocytes (mean [M] = 916 versus 1206 cells/mm(3) × 10(3); F = 7.8, p = .007), more CD8(+) cells (M = 1046 versus 720 cells/mm(3) × 10(3); F = 7.98, p = .006), and diminished natural killer cell cytotoxicity (M = -0.29 versus 0.41; F = 8.87, p = .004). School entry was associated with changes in immune parameters, but HIV status was not associated with the magnitude of changes. Changes in immune parameters after school entry were associated with family stress and preschool entry ANS reactivity. Highly ANS reactive children had either the greatest increase in CD8(+) cells after school entry or the greatest decrease, depending on reported levels of family adversity (B = 215.35; t = 3.74, p < .001). Changes in functional immune assays were significantly associated with the interactions between HIV status and ANS reactivity. CONCLUSIONS These results suggest that autonomic reactivity is associated with increased immunological sensitivity to adverse or challenging social contexts among children affected by HIV.
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Affiliation(s)
- Melanie R Thomas
- University of California, San Francisco, San Francisco, CA, USA.
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Seroprevalence of Brucellosis in HIV-Infected Patients in Sanandaj, Iran. ARCHIVES OF CLINICAL INFECTIOUS DISEASES 2013. [DOI: 10.5812/archcid.16989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Detectable viral load aggravates immunosenescence features of CD8 T-cell subsets in vertically HIV-infected children. J Acquir Immune Defic Syndr 2012; 60:447-54. [PMID: 22549383 DOI: 10.1097/qai.0b013e318259254f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND CD8 T cells are crucial in the immune responses against HIV infection, but HIV-infected adults suffer a naive CD8 T-cell depletion and accelerated senescence caused by chronic antigen stimulation. Although HIV-infected children preserve a better immune reconstitution capacity their CD8 responses are defective. We wanted to know, whether HIV vertical transmission produces a premature aging of the CD8 population due to antigen exposition to HIV from birth and persistent chronic activation. METHODS We conducted a multicentre cross-sectional study that compared vertically HIV-infected children with detectable (viremic) or undetectable (aviremic) viral load and age-matched healthy children. Using multiparameter flow cytometry, we studied within the CD8 population the frequencies of naive, memory, effector memory (effector memory), and TemRA subsets and measured markers of senescence, activation, and proliferation in these cells. RESULTS We found that naive subset in viremic children was markedly decreased and had a replicative senescence phenotype. Furthermore, viremic children showed increased frequencies of memory, TEM and TemRA CD8 T cells, with a more activated and replicative senescence phenotype. We found that HIV-infected children with undetectable viral load have an increased senescence in memory and effector CD8 T cells, but the frequencies and phenotype of the CD8 subsets analyzed are comparable to healthy children. CONCLUSIONS [corrected] Our study shows that CD8 T cells of HIV-infected children have a more senescent phenotype when compared with age-matched healthy children. Interestingly enough, our results support the importance of maintaining undetectable viral load in HIV-infected children to avoid the premature ageing and dysfunction of CD8 T cells.
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Reduced thymic size but no evidence of impaired thymic function in uninfected children born to human immunodeficiency virus-infected mothers. Pediatr Infect Dis J 2011; 30:325-30. [PMID: 21085050 DOI: 10.1097/inf.0b013e3182019bc3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND HIV-exposed, uninfected (HIV-EU) infants present hematologic and immunologic abnormalities at birth, and it remains to be clarified whether these abnormalities persist beyond infancy, for instance, affecting vaccination responses. METHODS Thymic size and thymic output were evaluated in 20 HIV-EU children at 15 months of age and compared with 10 age- and gender-matched controls. Regulatory T-cells (Tregs) and immune activation as well as cytokine profiles were determined, and the antibody response to Haemophilus influenzae Type b (Hib) vaccination was evaluated. RESULTS Thymic size was significantly lower in HIV-EU children (P = 0.011). However, CD4 and CD8 counts did not differ between HIV-EU and control children. Likewise, thymic output estimated as CD4 cells expressing naive (CD45RA+CD62L+CD27+, P = 0.31) or recent thymic naive (CD45RA+CD27+CD31+, P = 0.13) phenotype, or CD4 cells containing T-cell receptor excision circles (P = 0.47) were comparable. HIV-EU children and controls had similar levels of activated cells (CD4+CD38+HLA-DR+, P = 0.87; CD8+CD38+HLA-DR+, P = 0.22), Tregs (CD4+CD25+CD127(low)FOXP3+, P = 0.53), and naive Tregs (CD4+CD25+CD127(low)FOXP3+CD45RA+CD27+, P = 0.65). Finally, comparable titers of Haemophilus influenzae Type b antibodies in the 2 groups were found (P = 0.43). CONCLUSION The study demonstrates reduced thymic size in HIV-EU children compared with children born to HIV-negative mothers, but no evidence of impaired thymic function, immune regulation, or antibody vaccination response was detected, suggesting that no qualitative immune deficits persist in HIV-EU children at 15 months of age.
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Brucellosis serology in HIV-infected patients. Int J Infect Dis 2010; 14:e904-6. [PMID: 20705498 DOI: 10.1016/j.ijid.2010.04.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 04/07/2010] [Accepted: 04/09/2010] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND An accelerated evolution of HIV to AIDS has been reported with brucellosis co-infection. The seroprevalence of brucellosis co-infection with HIV has not been investigated in a brucellosis endemic country like Iran. METHODS We performed a cross-sectional survey of brucellosis serology in HIV-infected patients attending a university hospital, as well as in healthy controls. A total of 90 HIV-positive patients and 100 healthy age-matched controls were recruited. The clinical characteristics, hemoglobin, and red blood cell, platelet, white blood cell, and CD4+ T cell counts were evaluated. RESULTS Positive brucellosis serology was significantly higher in HIV-infected patients than in controls (73.3% vs. 30%, respectively, odds ratio 6.42, p<0.001). It was also higher in males than females, p=0.001. Brucellosis-infected patients had significantly lower hemoglobin and white blood cell counts compared with brucellosis-uninfected patients (p<0.001). In HIV-positive patients, white blood cell count was significantly lower in brucellosis-infected than brucellosis-uninfected patients (p<0.05). CONCLUSIONS Our findings show that brucellosis infection is an important infection in HIV-infected patients. The treatment of brucellosis may be of great clinical importance in the management of HIV infection in a brucellosis endemic country like Iran.
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T-lymphocyte subsets in apparently healthy nigerian children. Int J Pediatr 2010; 2010:474380. [PMID: 20169116 PMCID: PMC2821635 DOI: 10.1155/2010/474380] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Accepted: 12/31/2009] [Indexed: 11/17/2022] Open
Abstract
Population studies showed that there are differences in T-lymphocytes subpopulation of normal children in different regions, and reference values in an area might be different from another. This study compared the values in our population with CDC and WHO reference values. Blood samples from 279 healthy, HIV-negative children <12 years of age were analysed for complete blood count, CD3+, CD4+, CD8+ counts and percentages. Except for CD8%, mean values for all parameters measured significantly decreased with age. CD4+ counts were higher in females than males, P < .05. Using the WHO criteria, 15.9% of subjects had low total lymphocyte count and 20.6% had low CD4 count. Children <3 years had median CD4% lower than WHO normal values. Our median CD4+ counts correlated with CDC values. Values used by WHO in infants are higher than ours. We suggest that our children be assessed using CDC reference values which correlate with ours.
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Su M, Hu R, Li H, Huang Y, Xu TL, Jiang FR. Development of CD3- and CD8-positive cells in human fetal ileum. Shijie Huaren Xiaohua Zazhi 2009; 17:3606-3610. [DOI: 10.11569/wcjd.v17.i35.3606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the distribution, location and growth of CD3- and CD8-positive cells in developing lymphoid tissue of human fetal ileum.
METHODS: Thirty samples of human fetal ileum between gestational weeks 9 and 32 were collected. CD3- and CD8-positive cells were identified by immunohistochemistry using the streptavidin-peroxidase method. The positive cells were counted using BioMias image analysis software, and the data were analyzed using the SPSS11.5 software package.
RESULTS: At gestational week 9, there were few CD3- and CD8-positive cells scattered in the connective tissue of the ileal wall. At week 11, these positive cells were distributed in small clusters. At week 17, CD3- and CD8-positive cells gathered together. The majority of positive cells were distributed in the connective tissue of mucosa, while few positive cells infiltrated into the ileal epithelium. At week 18, CD3- and CD8-positive cells were seen in the lymphoid nodules and participated in the organization of lymphoid nodules. After week 24, the number of the two types of positive cells gradually increased with fetal age, reaching the peak at week 28. The distribution of these positive cells were particularly prominent in aggregated lymphoid nodules. A significant positive correlation was noted between the number of CD3- and CD8-positive cells (r = 0.831, P < 0.01). The number of CD3-positive cells exceeded that of CD8-positive cells at all time points.
CONCLUSION: CD3- and CD8-positive T cells begin to appear at gestational week 9 when gut-associated lymphoid tissue is forming in human fetus. The development of CD3- and CD8-positive T cells is basically synchronous in human fetal ileum.
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Sridevi M, Mallaiah K. Production of Hydroxamate-Type of Siderophores by Rhizobium strains
from Sesbania sesban (L.) Merr. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/ijss.2008.28.34] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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