title: Changes in peripheral blood leucocytes of sheep experimentally infected with Mycoplasma agalactiae.
abstract: Contagious agalactia is a serious disease of small ruminants affecting mainly mammary glands, joints and eyes. In sheep, the main aetiological agent is Mycoplasma agalactiae (Ma) whose abilities to persist in the target organs are known. Since there is no information on the effect of acute and chronic Ma infection on circulating leucocytes, the present study was designed to monitor granulocytes, monocytes, T and B lymphocytes, by flow cytometry, in female lactating sheep nasally infected with Ma. A profound depletion of leucocytes was observed from day 5 to day 34 post infection (p.i.). In particular, while the granulocytes returned to baseline levels by day 12 p.i., the monocytes remained significantly low until day 20 p.i. The infection caused a prolonged depletion of peripheral T lymphocytes (both CD4(+) and CD8(+)) while B lymphocytes remained unaltered throughout the study. Mycoplasma agalactiae was detected by real-time PCR in several anatomical sites (ear, nose and milk) from day 2-5 p.i. until the end of the study (i.e., day 50 p.i.) while a transient bacteraemia was observed from day 5 to day 12 p.i. The leucopenia observed following intranasal Ma infection is likely due to leucocyte infiltration within the target organs.
authors.affiliation: Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy. Electronic address: mariarosaria.marinaro@iss.it.
authors.forename: Mariarosaria
authors.initials: M
authors.lastname: Marinaro
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Grazia
authors.initials: G
authors.lastname: Greco
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Elvira
authors.initials: E
authors.lastname: Tarsitano
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Gianpiero
authors.initials: G
authors.lastname: Ventrella
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Camero
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Marialaura
authors.initials: M
authors.lastname: Corrente
authors.affiliation: Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.affiliation: Department of Veterinary Medicine, Università degli Studi di Bari, Strada P.le per Casamassima Km 3, Valenzano, Bari 70010, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Buonavoglia
mesh_terms: D000818:Animals; D001402:B-Lymphocytes; D016470:Bacteremia; D005260:Female; D007774:Lactation; D007958:Leukocyte Count; D008892:Milk / Q000382:microbiology; D009000:Monocytes; D009175:Mycoplasma Infections / Q000097:blood / Q000473:pathology / Q000662:veterinary*; D045644:Mycoplasma agalactiae; D060888:Real-Time Polymerase Chain Reaction; D012756:Sheep; D012757:Sheep Diseases / Q000097:blood / Q000382:microbiology* / Q000473:pathology; D013601:T-Lymphocytes
keywords: CD4(+) T cell; CD8(+) T cells; Granulocytopenia; Lymphopenia; Monocytopenia; Mycoplasma agalactiae