Abstract
A hallmark of infection with Cryptococcus neoformans is depression of the immune system characterized by poor inflammatory responses and loss of delayed-type hypersensitivity (DTH) and antibody responses. T-suppressor cell (Ts) responses, elicited by the capsular polysaccharide (GXM) of the organism, are known to develop during infection. This study was undertaken to develop a method to inhibit the anti-GXM Ts response and thereby study the influence of the Ts response on immune responsiveness and survival in cryptococcosis. Antigen-presenting cells (APC), elicited with complete Freund's adjuvant (CFA), were treated in vitro with GXM (GXM-APC). The GXM-APC were injected intravenously into normal mice. These mice were resistant to induction of anti-GXM Ts cells when soluble GXM was administered in tolerogenic doses or when animals were infected with C. neoformans. Inhibition of the anti-GXM Ts response was specific to GXM as levan-APC did not inhibit induction of anti-GXM Ts cells. Inhibition of the anti-GXM Ts response could not be attributed to increased clearance of GXM due to induction of anti-GXM antibodies or other mechanisms. Anti-cryptococcal DTH responses were lost in mice by the second week of infection. However, treatment with GXM-APC, but not levan-APC, allowed mice to maintain their DTH response. GXM-APC pretreatment enhanced survival of infected mice compared with mice pretreated with levan-APC. These results show that GXM-APC induces immune responses that inhibit the induction of Ts responses and enhances DTH responses in infected mice. These responses correlate with enhanced survival after cryptococcal infection.
Full text
PDF





Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Asherson G. L., Colizzi V., Zembala M. An overview of T-suppressor cell circuits. Annu Rev Immunol. 1986;4:37–68. doi: 10.1146/annurev.iy.04.040186.000345. [DOI] [PubMed] [Google Scholar]
- Blackstock R., Hall N. K., Hernandez N. C. Characterization of a suppressor factor that regulates phagocytosis by macrophages in murine cryptococcosis. Infect Immun. 1989 Jun;57(6):1773–1779. doi: 10.1128/iai.57.6.1773-1779.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blackstock R., Hall N. K. Non-specific immunosuppression by Cryptococcus neoformans infection. Mycopathologia. 1984 Apr 30;86(1):35–43. doi: 10.1007/BF00437227. [DOI] [PubMed] [Google Scholar]
- Blackstock R., Hernandez N. C. Inhibition of macrophage phagocytosis in cryptococcosis: phenotypic analysis of the suppressor cell. Cell Immunol. 1988 Jun;114(1):174–187. doi: 10.1016/0008-8749(88)90264-x. [DOI] [PubMed] [Google Scholar]
- Blackstock R., McCormack J. M., Hall N. K. Induction of a macrophage-suppressive lymphokine by soluble cryptococcal antigens and its association with models of immunologic tolerance. Infect Immun. 1987 Jan;55(1):233–239. doi: 10.1128/iai.55.1.233-239.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blackstock R., Zembala M., Asherson G. L. Functional equivalence of cryptococcal and haptene-specific T suppressor factor (TsF). I. Picryl and oxazolone-specific TsF, which inhibit transfer of contact sensitivity, also inhibit phagocytosis by a subset of macrophages. Cell Immunol. 1991 Sep;136(2):435–447. doi: 10.1016/0008-8749(91)90365-i. [DOI] [PubMed] [Google Scholar]
- Blackstock R., Zembala M., Asherson G. L. Functional equivalence of cryptococcal and haptene-specific T suppressor factor (TsF). II. Monoclonal anti-cryptococcal TsF inhibits both phagocytosis by a subset of macrophages and transfer of contact sensitivity. Cell Immunol. 1991 Sep;136(2):448–461. doi: 10.1016/0008-8749(91)90366-j. [DOI] [PubMed] [Google Scholar]
- Britz J. S., Askenase P. W., Ptak W., Steinman R. M., Gershon R. K. Specialized antigen-presenting cells. Splenic dendritic cells and peritoneal-exudate cells induced by mycobacteria activate effector T cells that are resistant to suppression. J Exp Med. 1982 May 1;155(5):1344–1356. doi: 10.1084/jem.155.5.1344. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bulmer G. S., Sans M. D., Gunn C. M. Cryptococcus neoformans. I. Nonencapsulated mutants. J Bacteriol. 1967 Nov;94(5):1475–1479. doi: 10.1128/jb.94.5.1475-1479.1967. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Casadevall A., Mukherjee J., Devi S. J., Schneerson R., Robbins J. B., Scharff M. D. Antibodies elicited by a Cryptococcus neoformans-tetanus toxoid conjugate vaccine have the same specificity as those elicited in infection. J Infect Dis. 1992 Jun;165(6):1086–1093. doi: 10.1093/infdis/165.6.1086. [DOI] [PubMed] [Google Scholar]
- Dong Z. M., Murphy J. W. Intravascular cryptococcal culture filtrate (CneF) and its major component, glucuronoxylomannan, are potent inhibitors of leukocyte accumulation. Infect Immun. 1995 Mar;63(3):770–778. doi: 10.1128/iai.63.3.770-778.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fasler S., Aversa G., Terr A., Thestrup-Pedersen K., de Vries J. E., Yssel H. Peptide-induced anergy in allergen-specific human Th2 cells results in lack of cytokine production and B cell help for IgE synthesis. Reversal by IL-2, not by IL-4 or IL-13. J Immunol. 1995 Nov 1;155(9):4199–4206. [PubMed] [Google Scholar]
- Goldman D. L., Lee S. C., Casadevall A. Tissue localization of Cryptococcus neoformans glucuronoxylomannan in the presence and absence of specific antibody. Infect Immun. 1995 Sep;63(9):3448–3453. doi: 10.1128/iai.63.9.3448-3453.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Goldman D., Lee S. C., Casadevall A. Pathogenesis of pulmonary Cryptococcus neoformans infection in the rat. Infect Immun. 1994 Nov;62(11):4755–4761. doi: 10.1128/iai.62.11.4755-4761.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Graybill J. R., Alford R. H. Cell-mediated immunity in Cryptococcosis. Cell Immunol. 1974 Oct;14(1):12–21. doi: 10.1016/0008-8749(74)90164-6. [DOI] [PubMed] [Google Scholar]
- Hall N. K., Maluf K. C., Blackstock R. Functional testing and chemical composition of cryptococcal extracts. Sabouraudia. 1984;22(5):439–442. doi: 10.1080/00362178485380701. [DOI] [PubMed] [Google Scholar]
- Hill J. O. CD4+ T cells cause multinucleated giant cells to form around Cryptococcus neoformans and confine the yeast within the primary site of infection in the respiratory tract. J Exp Med. 1992 Jun 1;175(6):1685–1695. doi: 10.1084/jem.175.6.1685. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Huffnagle G. B., Toews G. B., Burdick M. D., Boyd M. B., McAllister K. S., McDonald R. A., Kunkel S. L., Strieter R. M. Afferent phase production of TNF-alpha is required for the development of protective T cell immunity to Cryptococcus neoformans. J Immunol. 1996 Nov 15;157(10):4529–4536. [PubMed] [Google Scholar]
- Kawakami K., Tohyama M., Qifeng X., Saito A. Expression of cytokines and inducible nitric oxide synthase mRNA in the lungs of mice infected with Cryptococcus neoformans: effects of interleukin-12. Infect Immun. 1997 Apr;65(4):1307–1312. doi: 10.1128/iai.65.4.1307-1312.1997. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Morgan M. A., Blackstock R. A., Bulmer G. S., Hall N. K. Modification of macrophage phagocytosis in murine cryptococcosis. Infect Immun. 1983 May;40(2):493–500. doi: 10.1128/iai.40.2.493-500.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mukherjee J., Scharff M. D., Casadevall A. Protective murine monoclonal antibodies to Cryptococcus neoformans. Infect Immun. 1992 Nov;60(11):4534–4541. doi: 10.1128/iai.60.11.4534-4541.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Murphy J. W. Clearance of Cryptococcus neoformans from immunologically suppressed mice. Infect Immun. 1989 Jul;57(7):1946–1952. doi: 10.1128/iai.57.7.1946-1952.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Murphy J. W., Moorhead J. W. Regulation of cell-mediated immunity in cryptococcosis. I. Induction of specific afferent T suppressor cells by cryptococcal antigen. J Immunol. 1982 Jan;128(1):276–283. [PubMed] [Google Scholar]
- Murphy J. W., Mosley R. L., Cherniak R., Reyes G. H., Kozel T. R., Reiss E. Serological, electrophoretic, and biological properties of Cryptococcus neoformans antigens. Infect Immun. 1988 Feb;56(2):424–431. doi: 10.1128/iai.56.2.424-431.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nowak T. P., Barondes S. H. Agglutinin from Limulus polyphemus. Purification with formalinized horse erythrocytes as the affinity adsorbent. Biochim Biophys Acta. 1975 May 30;393(1):115–123. [PubMed] [Google Scholar]
- Robinson B. E., Hall N. K., Bulmer G. S., Blackstock R. Suppression of responses to cryptococcal antigen in murine cryptococcosis. Mycopathologia. 1982 Dec 27;80(3):157–163. doi: 10.1007/BF00437578. [DOI] [PubMed] [Google Scholar]
- Tsukada H., Kawamura I., Arakawa M., Nomoto K., Mitsuyama M. Dissociated development of T cells mediating delayed-type hypersensitivity and protective T cells against Listeria monocytogenes and their functional difference in lymphokine production. Infect Immun. 1991 Oct;59(10):3589–3595. doi: 10.1128/iai.59.10.3589-3595.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Vecchiarelli A., Retini C., Monari C., Tascini C., Bistoni F., Kozel T. R. Purified capsular polysaccharide of Cryptococcus neoformans induces interleukin-10 secretion by human monocytes. Infect Immun. 1996 Jul;64(7):2846–2849. doi: 10.1128/iai.64.7.2846-2849.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
