title: Anti-Listeria monocytogenes immunity in mu-suppressed mice: a comparison of treatment with conventional hyperimmune rabbit anti-mouse IgM and affinity-purified, monoclonal rat anti-mouse IgM.
abstract: The capacity of anti-IgM treated, B-cell-depleted mice to control infection by Listeria monocytogenes was evaluated. Suppression was achieved with a hyperimmune rabbit anti-mouse-IgM antiserum (IRS), with affinity-purified IRS (IRP), or with an affinity-purified, monoclonal, rat anti-mouse-IgM antibody (LO-MM-9). B-cell depletion in specifically treated mice was judged to be complete by the following criteria: absence of significant response to a B-cell mitogen lipopolysaccharide, absence of B-cells with detectable IgM or kappa light chain on their surface, absence of detectable IgM, and presence of free anti-IgM antibodies in serum. BALB/c mice, conventionally treated from birth with IRS, had an increased capacity to clear L. monocytogenes from the blood during the first 5 min after intravenous infection. Furthermore, control of infection seemed to be enhanced during the first 24 h but was found to be impaired when assessed 3 and 4 days after initiation of infection. These effects were, however, not IRS specific, because control mice treated with normal rabbit serum behaved comparably. Mortality caused by 2 x 10(3) L. monocytogenes injected intraperitoneally into BALB/c mice susceptible to L. monocytogenes was increased more in NRS-than in IRS-treated mice when both were compared with untreated control mice. Therefore, chronic injection of IRS or NRS seemed to disturb anti-L. monocytogenes immunity, rendering an evaluation of the role of antibodies impossible.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000302:isolation & purification / Q000627:therapeutic use*; D007075:Immunoglobulin M / Q000008:administration & dosage / Q000276:immunology* / Q000302:isolation & purification; D007148:Immunoglobulin mu-Chains / Q000008:administration & dosage / Q000276:immunology* / Q000302:isolation & purification; D007165:Immunosuppression Therapy; D008089:Listeria monocytogenes / Q000276:immunology*; D008088:Listeriosis / Q000276:immunology* / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D000911:Antibodies, Monoclonal; D007075:Immunoglobulin M; D007148:Immunoglobulin mu-Chains