Restricted B-cell responses to microbial challenge of the respiratory tract.
The local B-cell response in the respiratory tract to infectious challenge has been analyzed in pigs and calves using two techniques: flow cytometry and antibody secreting cell (ASC) probes. Pneumonia in pigs caused by experimental infection with Mycoplasma hyopneumoniae resulted in a 25-fold increase in the B-cell population in BAL and lung parenchyma 28 days post infection. ASC probes revealed that the B-cell response of immune pigs to a large challenge infection was localized to lung parenchyma and tracheobronchal lymph nodes. Naive calves infected with Pasteurella multocida had a 5-fold increase in the B-cell blast population in lung parenchyma and BAL, and a greater than 60-fold increase in the draining lymph node at 9 days post infection. The ASC probes prepared post challenge from immune calves showed the response to be localized to the draining lymph nodes, with little response in lung parenchyma. A major finding was that ASC probes prepared from lung parenchyma and from pulmonary lymph nodes of both calves and pigs recognized a restricted range of bacterial antigens, particularly compared to the range of antigens recognized by concurrently circulating sera. The use of ASC probes demonstrates that there is a restricted B-cell repertoire in the respiratory tract.
Walker
J
J
CSL Ltd. A.C.N. 051 588 348, Parkville Victoria, Australia.
Lee
R
R
Mathy
N
N
Doughty
S
S
Conlon
J
J
D000818:Animals; D000918:Antibody Specificity / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D002417:Cattle; D018928:Immunity, Mucosal / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D009177:Mycoplasma pneumoniae / Q000276:immunology* / Q000472:pathogenicity; D010326:Pasteurella Infections / Q000209:etiology / Q000276:immunology*; D016979:Pasteurella multocida / Q000276:immunology* / Q000472:pathogenicity; D045729:Pneumonia of Swine, Mycoplasmal / Q000209:etiology / Q000276:immunology*; D012137:Respiratory System / Q000166:cytology / Q000276:immunology* / Q000382:microbiology*; D013552:Swine