Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2006-9-19
pubmed:abstractText
Maintenance of immunity to persistent pathogens is poorly understood. In this study, we used a murine model of persistent pulmonary fungal infection to study the ongoing cell-mediated immune response. CBA/J mice with low-level persistent Cryptococcus neoformans infection had CD4+ T cells of effector memory phenotype present in their lungs. Although unable to eliminate the primary infection to sterility, these mice displayed hallmarks of immunologic memory in response to rechallenge with C. neoformans: 1) the secondary cryptococcal challenge was controlled much more rapidly, 2) the inflammatory response developed and resolved more rapidly, 3) CD4+ T and CD8+ T cell responses were higher in magnitude, and 4) effector cytokine production by T cells was greatly enhanced. Depletion of CD4+ T cells at the time of secondary challenge adversely affected clearance of C. neoformans from the lungs. These results demonstrate that persistent low-level infection with C. neoformans does not impair the cell-mediated response to the fungus. Although they are relatively free of overt disease, these mice can respond with a rapid secondary immune response if the burden of C. neoformans increases. These data support the concept that immunologically healthy individuals can maintain low numbers of cryptococci that can become a nidus for re-activation disease during immunodeficient states such as AIDS.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
177
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4652-61
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:16982904-Animals, pubmed-meshheading:16982904-Antibodies, Fungal, pubmed-meshheading:16982904-CD4-Positive T-Lymphocytes, pubmed-meshheading:16982904-CD8-Positive T-Lymphocytes, pubmed-meshheading:16982904-Cryptococcosis, pubmed-meshheading:16982904-Cryptococcus neoformans, pubmed-meshheading:16982904-Cytokines, pubmed-meshheading:16982904-Disease Models, Animal, pubmed-meshheading:16982904-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:16982904-Female, pubmed-meshheading:16982904-Flow Cytometry, pubmed-meshheading:16982904-Homeostasis, pubmed-meshheading:16982904-Immunity, Cellular, pubmed-meshheading:16982904-Immunization, Secondary, pubmed-meshheading:16982904-Immunologic Memory, pubmed-meshheading:16982904-Inflammation, pubmed-meshheading:16982904-Lung, pubmed-meshheading:16982904-Lung Diseases, Fungal, pubmed-meshheading:16982904-Mice, pubmed-meshheading:16982904-Mice, Inbred CBA
pubmed:year
2006
pubmed:articleTitle
Immunologic homeostasis during infection: coexistence of strong pulmonary cell-mediated immunity to secondary Cryptococcus neoformans infection while the primary infection still persists at low levels in the lungs.
pubmed:affiliation
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, N.I.H., Extramural