Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1982-7-22
pubmed:abstractText
Mycobacteria have the ability to enhance or depress immune responses. This paper describes experiments designed to investigate the parameters determining the direction of modulation. It has been shown previously that 10(8) liver Mycobacterium bovis BCG depress the ability of mouse spleen cells to produce a primary antibody response in vitro to SRBC 2-3 weeks after i.v. injection, whereas the same number of dead organisms enhance this response. Using the same growth medium for the BCG (Glaxo glycerol-free medium), we now find that decreasing the BCG dose to mice from 10(8) to 10 (6) liver organisms results in enhanced responses and increasing the dose to more than 10(8) dead organisms results in depressed responses. It thus appears that bacterial load is the important factor determining whether depression or enhancement of the primary antibody response will occur, rather than the viability of the organisms per se. However, when the BCG was grown in Middlebrook 7H9 broth, doses as high as 4 X 10(9) dead BCG/mouse failed to depress although depressed responses were found if sufficient live organisms (7 X 10(8)) were injected. In view of the known growth characteristics of BCG in these 2 bacteriological media, it is suggested that the degree of aggregation of the injected suspension may also be of importance in determining whether or not depression will occur. A comparison of the effects of BCG injected untreated or after dispersion of bacterial aggregates supports this idea. Some degree of splenomegaly was always found in mice with depressed splenic responses but a large spleen did not necessarily yield cell suspensions with depressed responses.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0007-1021
pubmed:author
pubmed:issnType
Print
pubmed:volume
63
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
133-43
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Mycobacterium bovis, BCG, modulation of murine antibody responses: influence of dose and degree of aggregation of live or dead organisms.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't