This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Navalkar, R. G. Articles by Levy, L. Search for Related Content PubMed PubMed Citation Articles by Navalkar, R. G. Articles by Levy, L.

 Previous Article  |  Next Article 

Infect Immun. 1974 December; 10(6): 1302-1306
Copyright © 1974 American Society for Microbiology. All Rights Reserved.

Immune Response to Mycobacterium leprae: Plaque-Forming Cells in Mice

Department of Microbiology, Meharry Medical College, Nashville, Tennessee 37208
Leprosy Research Unit, Public Health Service Hospital, San Francisco, California 94118

ABSTRACT

Intravenous immunization with a cell extract of Mycobacterium leprae produced a primary immune response of considerable magnitude, followed by an equally large response after secondary stimulation, as measured by assay of plaque-forming cells (PFC). Infection with M. leprae or immunization with cell extract by the footpad route produced a lower level of response than that seen in the intravenous group. Identical patterns of response, although not of the same magnitude, were observed after both primary and secondary challenges in the two footpad groups, one infected with viable M. leprae and the other immunized with M. leprae cell extract. The secondary response after a booster dose to all these groups appeared to be an enhanced immunoglobulin M response. Control studies confirmed that the immune response was a direct result of the host-parasite interaction and that the PFC observed resulted from stimulation of antibody-forming cells by antigens of M. leprae. The similarity in time of appearance of peak PFC levels in the two footpad groups may be attributed to the live challenge passing through a latent phase. Alternatively, the challenge is known to contain a large proportion on nonviable cells, and it may also contain soluble M. leprae antigens. Studies of the cross-reactivity of the antigens have extended previous observations on antigens shared between M. leprae and other mycobacterial species. Use of the two antigen-containing fractions of the M. leprae cell extract has suggested that one of the fractions contains some shared antigens, whereas the other has an antigen specific to M. leprae.