title: Levels of immune cells in transcendental meditation practitioners.
abstract: BACKGROUND
  Relationships between mind and body have gradually become accepted. Yogic practices cause modulation of the immune system. Transcendental meditation (TM) is a specific form of mantra meditation. We reported previously different plasma levels of catecholamines and pituitary hormones in TM practitioners comparing with a control group, and patterns of the daytime secretion of these hormones different from those normally described.
  
  
  OBJECTIVE
  The aim of the following study is to evaluate the immune system in these meditation practitioners, by determining leukocytes and lymphocytes subsets.
  
  
  METHODS
  TM group consisted of 19 subjects who regularly practice either TM or the more advanced Sidhi-TM technique. A control group consisted of 16 healthy subjects who had not previously used any relaxation technique. Total leukocytes, granulocytes, lymphocytes and monocytes were counted by an automated quantitative hematology analyzer, whereas lymphocytes subsets were determined by flow cytometry. Samples were taken from each subject at 0900 h after an overnight fast.
  
  
  RESULTS
  The results indicated that the TM group had higher values than the control group in CD3+CD4-CD8+ lymphocytes (P < 0.05), B lymphocytes (P < 0.01) and natural killer cells (P < 0.01), whereas CD3+CD4+CD8- lymphocytes showed low levels in meditation practitioners (P < 0.001). No significant differences were observed in total leukocytes, granulocytes, monocytes, total lymphocytes or CD3+ lymphocytes comparing both groups.
  
  
  CONCLUSIONS
  The technique of meditation studied seems to have a significant effect on immune cells, manifesting in the different circulating levels of lymphocyte subsets analyzed. The significant effect of TM on the neuroendocrine axis and its relationship with the immune system may partly explain our results.
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Jose R
authors.initials: JR
authors.lastname: Infante
authors.affiliation: Biochemical Service, Virgen de las Nieves Hospital, Fuerzas Armadas Avd. nº2, E-18014, Granada, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Peran
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Juan I
authors.initials: JI
authors.lastname: Rayo
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Justo
authors.initials: J
authors.lastname: Serrano
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Domínguez
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Lucia
authors.initials: L
authors.lastname: Garcia
authors.affiliation: Nuclear Medicine Service, Infanta Cristina Hospital, Elvas Avd., s/n, E-06080, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Duran
authors.affiliation: Area Health Service, Merida, Badajoz, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Roldan
keywords: Immune system; psychoneuroimmunology; stress; transcendental meditation; yoga