title: Influence of fixation and immunohistological technique on accuracy, precision and inter-observer reproducibility of plasma cell counting.
abstract: Recently two highly sensitive and specific diagnostic criteria for Sjögren's syndrome based on percentages of IgA-, IgG-, and IgM-containing plasma cells measured in immunohistologically stained labial salivary gland tissue have been described. The reliability of such a criterion is dependent on the accuracy, precision and inter-observer reproducibility in plasma cell counting. The present study evaluates the effect of tissue fixation and immunohistological procedures on the aforementioned factors. Immunoglobulin (Ig)-containing plasma cells in sections of lamellated submandibular salivary gland tissue, alternately fixed in a 4% buffered formol solution or formol-sublimate solution and stained with an indirect immunoperoxidase and unlabelled peroxidase anti-peroxidase (PAP) method respectively, were enumerated by three independent observers. Relative numbers of Ig-containing plasma cells appeared to be less sensitive for systematic errors due to tissue fixation and immunohistological procedure than absolute numbers of Ig-containing plasma cells. The best inter-observer reproducibility of plasma cell counts was obtained in sections from formol sublimate-fixed specimens stained according to the PAP procedure.
authors.affiliation: Department of Pathology, University Hospital, Nijmegen, The Netherlands.
authors.forename: C
authors.initials: C
authors.lastname: Bodeutsch
authors.forename: P C
authors.initials: PC
authors.lastname: de Wilde
authors.forename: J C
authors.initials: JC
authors.lastname: van Houwelingen
authors.forename: G P
authors.initials: GP
authors.lastname: Ebben
authors.forename: H M
authors.initials: HM
authors.lastname: Kerstens
authors.forename: L
authors.initials: L
authors.lastname: Kater
authors.forename: L B
authors.initials: LB
authors.lastname: van de Putte
authors.forename: G P
authors.initials: GP
authors.lastname: Vooijs
mesh_terms: D000704:Analysis of Variance; D002452:Cell Count / Q000379:methods*; D005404:Fixatives; D006801:Humans; D007124:Immunoenzyme Techniques; D007136:Immunoglobulins / Q000032:analysis; D007150:Immunohistochemistry; D015588:Observer Variation; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology*; D012859:Sjogren's Syndrome / Q000175:diagnosis; D013194:Staining and Labeling; D013363:Submandibular Gland / Q000276:immunology; D016707:Tissue Fixation
chemical_list: D005404:Fixatives; D007136:Immunoglobulins