Blood and milk cellular immune responses of mastitic non-periparturient cows inoculated with Staphylococcus aureus.
Can J Vet Res
; 66(2): 125-31, 2002 Apr.
Article
in En
| MEDLINE
| ID: mdl-11989735
ABSTRACT
Lymphocyte function and phenotype of peripheral blood and mammary gland cells were evaluated in non-periparturient cows before and at 1, 4 to 8 and 9 to 14 d after inoculation with Staphylococcus aureus, as expressed by percentage of CD3+, CD2+, and CD45R+ cells, antigen density of these markers per lymphocyte, and mitogen-induced blastogenesis. Milk bacterial counts and somatic cell counts (SCC) were also assessed. Mitogen-induced blastogenic responses were strong in blood and weak in mammary gland cells in all observations and positively correlated with the percent of CD45R+ cells. Significantly greater percentages of milk CD3+ lymphocytes and increased CD3, CD2, and CD45R antigen density per cell were observed after challenge. The blood CD3 and CD2 antigen density per lymphocyte and the milk CD2+ lymphocyte percent were negatively correlated with SCC (P < or = 0.01). No mastitis (SCC < or = 500 000 cells/mL) was observed in cows showing blood lymphocyte CD2 and CD3 antigen density indices < or = 2.5 and 6, respectively. Forty-one percent of SCC values were predicted by the combined blood CD2 and milk CD3 antigen density (P < or = 0.01). These findings support the hypotheses that mitogen-induced lymphocyte blastogenesis is not a valid test to assess mammary gland immunocompetence and that CD2 expression may facilitate immune responses by decreasing the number of T cell receptors required to achieve full activation.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Staphylococcal Infections
/
Staphylococcus aureus
/
Milk
/
Mastitis, Bovine
Type of study:
Diagnostic_studies
/
Prognostic_studies
Limits:
Animals
Language:
En
Journal:
Can J Vet Res
Journal subject:
MEDICINA VETERINARIA
Year:
2002
Type:
Article
Affiliation country:
United States