VaccHemInf project: protocol for a prospective cohort study of efficacy, safety and characterisation of immune functional response to vaccinations in haematopoietic stem cell transplant recipients

• Published in: BMJ open Vol. 9; no. 2; p. e026093
• Main Authors: Conrad, Anne, Boccard, Mathilde, Valour, Florent, Alcazer, Vincent, Tovar Sanchez, Aydee-Tamara, Chidiac, Christian, Laurent, Frédéric, Vanhems, Philippe, Salles, Gilles, Brengel-Pesce, Karen, Meunier, Boris, Trouillet-Assant, Sophie, Ader, Florence
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group LTD 15-02-2019; BMJ Publishing Group
• Subjects: Adults; Antibodies, Bacterial - blood; Antibodies, Viral - blood; Antigens; Biomarkers; Blood & organ donations; Cohort analysis; Diphtheria Toxin - immunology; Flow Cytometry; France; Graft versus host disease; Graft vs Host Disease - immunology; Haemophilus influenzae type b - immunology; Hematology; Hematopoietic Stem Cell Transplantation; Hepatitis; Hepatitis B virus - immunology; Humans; Immune system; Infections; Infectious Diseases; Leukemia; Longitudinal Studies; Postoperative Care; Prospective Studies; Schedules; Sepsis; Stem cell transplantation; Stem cells; Streptococcus pneumoniae - immunology; Tetanus; Tetanus Toxin - immunology; Transplantation Immunology; Transplants & implants; Vaccination; Vaccines; Vaccines - immunology; France; haematopoietic stem cell transplantation; immune functional assay; allogeneic haematopoietic stem cell transplantation; autologous haematopoietic stem cell transplantation; chronic graft-versus-host disease; vaccination
• ISSN: 2044-6055; 2044-6055
• DOI: 10.1136/bmjopen-2018-026093

IntroductionImmune reconstitution after haematopoietic stem cell transplantation (HSCT) is a complex and dynamic process, varying from a state of nearly complete immunosuppression to an expected full immune recovery. Specific vaccination guidelines recommend reimmunisation after HSCT but data regarding vaccine efficacy in this unique population are scarce. New immune functional assays could enable prediction of vaccine response in the setting of HSCT.Methods and analysisA prospective, longitudinal single-centre cohort study of autologous and allogeneic HSCT recipients was designed in order to determine the vaccine response to five vaccine targets (pneumococcus, hepatitis B virus, Haemophilus Influenzae type b, tetanus and diphtheria) and to correlate it to immune function parameters. A workflow was set up to study serological response to vaccines and to describe the functional immune status of 100 HSCT recipients (50 autologous and 50 allogeneic) before and 3, 12 and 24 months after primary immunisation. At each time point, ‘basic’ immune status recording (serology, immunophenotyping of lymphocyte subsets by flow cytometry) will be assessed. The immune response will furthermore be evaluated before and 3 months after primary vaccination by two ex vivo immune functional assays assessing: (1) tumour necrosis factor alpha, interferon gamma production and host messenger RNA expression on whole-blood stimulation by lipopolysaccharide or Staphylococcus aureus enterotoxin B and (2) T-lymphocyte proliferation in response to a standard mitogen (phytohaemagglutinin) or to selected recall antigens. Reference intervals will be determined from a cohort of 30 healthy volunteers. This translational study will provide data describing vaccine response, immune functionality of HSCT recipients over time and will allow mapping HSCT recipients with regard to their immune function.Ethics and disseminationEthical approval has been obtained from the institutional review board (no 69HCL17_0769). Results will be communicated at scientific meetings and submitted for publication in peer-reviewed journals.Trial registration number NCT03659773; Pre-results.