title: Longitudinal analysis of immune abnormalities in varying severities of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis patients.
abstract: BACKGROUND
  Research has identified immunological abnormalities in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), a heterogeneous illness with an unknown cause and absence of diagnostic test. There have been no CFS/ME studies examining innate and adaptive immune cells longitudinally in patients with varying severities. This is the first study to investigate immune cells over 6 months while also examining CFS/ME patients of varying symptom severity.
  
  
  METHODS
  Participants were grouped into 18 healthy controls, 12 moderate and 12 severe CFS/ME patients and flow cytometry was used to examine cell parameters at 0 and 6 months.
  
  
  RESULTS
  Over time, iNKT CD62L expression significantly increased in moderate CFS/ME patients and CD56(bright) NK receptors differed in severe CFS/ME. Naïve CD8(+)T cells, CD8(-)CD4(-) and CD56(-)CD16(-) iNKT phenotypes, γδ2T cells and effector memory subsets were significantly increased in severe CFS/ME patients at 6 months. Severe CFS/ME patients were significantly reduced in CD56(bright)CD16(dim) NKG2D, CD56(dim)CD16(-) KIR2DL2/DL3, CD94(-)CD11a(-) γδ1T cells and CD62L(+)CD11a(-) γδ1T cells at 6 months.
  
  
  CONCLUSIONS
  Severe CFS/ME patients differed from controls and moderate CFS/ME patients over time and expressed significant alterations in iNKT cell phenotypes, CD8(+)T cell markers, NK cell receptors and γδT cells at 6 months. This highlights the importance of further assessing these potential immune biomarkers longitudinally in both moderate and severe CFS/ME patients.
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. sharni.hardcastle@hotmail.com.
authors.forename: Sharni Lee
authors.initials: SL
authors.lastname: Hardcastle
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. e.brenu@griffith.edu.au.
authors.forename: Ekua Weba
authors.initials: EW
authors.lastname: Brenu
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. samanthajohnston3@griffithuni.edu.au.
authors.forename: Samantha
authors.initials: S
authors.lastname: Johnston
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. thao.nguyen@griffithuni.edu.au.
authors.forename: Thao
authors.initials: T
authors.lastname: Nguyen
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. teilah.huth@griffithuni.edu.au.
authors.forename: Teilah
authors.initials: T
authors.lastname: Huth
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. s.ramos@griffith.edu.au.
authors.forename: Sandra
authors.initials: S
authors.lastname: Ramos
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. dstaines@bigpond.net.au.
authors.forename: Donald
authors.initials: D
authors.lastname: Staines
authors.affiliation: National Centre for Neuroimmunology and Emerging Diseases, 9.22, G40 Griffith Health Institute, School of Medical Science, Griffith University, Parklands Drive, Gold Coast, QLD, 4222, Australia. s.marshall-gradisnik@griffith.edu.au.
authors.forename: Sonya
authors.initials: S
authors.lastname: Marshall-Gradisnik
mesh_terms: D056704:Adaptive Immunity / Q000276:immunology; D000328:Adult; D000368:Aged; D019002:CD56 Antigen / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D015673:Fatigue Syndrome, Chronic / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D019041:L-Selectin / Q000378:metabolism; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D055611:Natural Killer T-Cells / Q000276:immunology; D010641:Phenotype; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology; D055815:Young Adult
chemical_list: D019002:CD56 Antigen; C522918:NCAM1 protein, human; D016692:Receptors, Antigen, T-Cell, gamma-delta; D019041:L-Selectin