{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T12:18:45Z","timestamp":1784204325636,"version":"3.55.0"},"reference-count":43,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,5,27]],"date-time":"2022-05-27T00:00:00Z","timestamp":1653609600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Bando F. CARISBO RMTC 2020","award":["#19096"],"award-info":[{"award-number":["#19096"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Sickle cell disease (SCD) is a condition of functional hypo-\/a-splenism in which predisposition to bacterial infections is only a facet of a wide spectrum of immune-dysregulation disorders forming the clinical expression of a peculiar immunophenotype. The objective of this study was to perform an in-depth immunophenotypical characterization of SCD pediatric patients, looking for plausible correlations between immunological biomarkers, the impact of hydroxyurea (HU) treatment and clinical course. This was an observational case\u2013control study including 43 patients. The cohort was divided into two main groups, SCD subjects (19\/43) and controls (24\/43), differing in the presence\/absence of an SCD diagnosis. The SCD group was split up into HU+ (12\/19) and HU\u2212 (7\/19) subgroups, respectively receiving or not a concomitant HU treatment. The principal outcomes measured were differences in the immunophenotyping between SCD patients and controls through chi-squared tests, t-tests, and Pearson\u2019s correlation analysis between clinical and immunological parameters. Leukocyte and neutrophil increase, T-cell depletion with prevalence of memory T-cell compartment, NK and B-na\u00efve subset elevation with memory and CD21low B subset reduction, and IgG expansion, significantly distinguished the SCD HU\u2212 subgroup from controls, with na\u00efve T cells, switched-memory B cells and IgG maintaining differences between the SCD HU+ group and controls (p-value of &lt;0.05). The mean CD4+ central-memory T-cell% count was the single independent variable showing a positive correlation with vaso-occlusive crisis score in the SCD group (Pearson\u2019s R = 0.039). We report preliminary data assessing plausible clinical implications of baseline and HU-related SCD immunophenotypical alterations, which need to be validated in larger samples, but potentially affecting hypo-\/a-splenism immuno-chemoprophylactic recommendations.<\/jats:p>","DOI":"10.3390\/jcm11113037","type":"journal-article","created":{"date-parts":[[2022,5,28]],"date-time":"2022-05-28T01:40:45Z","timestamp":1653702045000},"page":"3037","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["In-Depth Immunological Typization of Children with Sickle Cell Disease: A Preliminary Insight into Its Plausible Correlation with Clinical Course and Hydroxyurea Therapy"],"prefix":"10.3390","volume":"11","author":[{"given":"Giulia","family":"Giulietti","sequence":"first","affiliation":[{"name":"Specialty School of Paediatrics, University of Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniele","family":"Zama","sequence":"additional","affiliation":[{"name":"Pediatric Emergency Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3665-8926","authenticated-orcid":false,"given":"Francesca","family":"Conti","sequence":"additional","affiliation":[{"name":"Pediatric Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mattia","family":"Moratti","sequence":"additional","affiliation":[{"name":"Specialty School of Paediatrics, University of Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Teresa","family":"Presutti","sequence":"additional","affiliation":[{"name":"Otolaryngology Department, University Hospital of Modena, 41125 Modena, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tamara","family":"Belotti","sequence":"additional","affiliation":[{"name":"Pediatric Oncology and Hematology Unit \u201cLalla Ser\u00e0gnoli\u201d, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Elena","family":"Cantarini","sequence":"additional","affiliation":[{"name":"Pediatric Oncology and Hematology Unit \u201cLalla Ser\u00e0gnoli\u201d, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elena","family":"Facchini","sequence":"additional","affiliation":[{"name":"Pediatric Oncology and Hematology Unit \u201cLalla Ser\u00e0gnoli\u201d, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mirna","family":"Bassi","sequence":"additional","affiliation":[{"name":"Pediatric Oncology and Hematology Unit \u201cLalla Ser\u00e0gnoli\u201d, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paola","family":"Selva","sequence":"additional","affiliation":[{"name":"Laboratory of Immuno-Haematology-Laboratorio Unico Metropolitano, Azienda USL, 40133 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elisabetta","family":"Magrini","sequence":"additional","affiliation":[{"name":"Laboratory of Immuno-Haematology-Laboratorio Unico Metropolitano, Azienda USL, 40133 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marcello","family":"Lanari","sequence":"additional","affiliation":[{"name":"Pediatric Emergency Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0379-9562","authenticated-orcid":false,"given":"Andrea","family":"Pession","sequence":"additional","affiliation":[{"name":"Pediatric Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, 40138 Bologna, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1561","DOI":"10.1056\/NEJMra1510865","article-title":"Sickle Cell Disease","volume":"376","author":"Piel","year":"2017","journal-title":"N. 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