Prolonged depletion of circulating CD4+ T lymphocytes and acute monocytosis after pantropic canine coronavirus infection in dogs.
A hypervirulent strain (CB/05) of canine coronavirus was employed to infect oronasally 11-week-old pups. Peripheral blood monocytes (CD14(+)), T lymphocytes (CD4(+) and CD8(+)) and B lymphocytes (CD21(+)) were studied by flow cytometry within 5 days post-infection (p.i.) and at later time points. Infection with CB/05 resulted in a profound depletion of T cells and a slight loss of B cells in the first week p.i. In particular, while the CD8(+) and the B lymphocytes returned to baseline levels by day 7 p.i., the CD4(+) T cells remained significantly low until day 30 p.i. and recovered completely only at day 60 p.i. Monocytosis was also observed after CB/05 infection with a peak at day 5 p.i. The prolonged depletion of peripheral CD4(+) T cells did not alter the levels of serum IgG or IgM. The impact of CB/05 infection on the immune performance of infected pups is discussed.
Marinaro
Mariarosaria
M
Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome, Italy. mariarosaria.marinaro@iss.it
Mari
Viviana
V
Bellacicco
Anna Lucia
AL
Tarsitano
Elvira
E
Elia
Gabriella
G
Losurdo
Michele
M
Rezza
Giovanni
G
Buonavoglia
Canio
C
Decaro
Nicola
N
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002478:Cells, Cultured; D018352:Coronavirus Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D017939:Coronavirus, Canine / Q000276:immunology / Q000502:physiology*; D004283:Dog Diseases / Q000276:immunology* / Q000821:virology; D004285:Dogs; D005260:Female; D007958:Leukocyte Count; D008297:Male; D009000:Monocytes / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology