Characterization of a cell population which amplifies the anticryptococcal delayed-type hypersensitivity response

Fidel, Paul L.; Murphy, Juneann W.

doi:10.1128/iai.58.2.393-398.1990

Cited by 16 publications

(20 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The mechanism(s) by which T cells mediated the early resistance observed in the lungs and spleen of bg/bg nul+ mice is not clear, but it has been established that T cells, either through direct cytotoxic effects (16,22) or secretion of lymphokines that would activate other effector cells (12,17,33,41), are central in resistance to cryptococcosis (11,30). Despite low NK activity in both bg/bg nulnu and bg/bg nul+ mice, we have shown that NK cells from both genotypes were capable of responding to IL-2 and the interferon inducer poly(I:C).…”

Section: Discussionmentioning

confidence: 99%

Pathogenesis of Cryptococcus neoformans in congenitally immunodeficient beige athymic mice

Salkowski

Balish

1990

Infect Immun

View full text Add to dashboard Cite

Mortality after intravenous challenge with 104 Cryptococcus neoformans demonstrated that doubly immunodeficient beige athymic (bg/bg nu/nu) mice were more susceptible to systemic cryptococcosis than either bg/bg or nulnu mice. Infected bg/bg nu/nu mice also had a shortened lifespan compared with their bg/bg nul+ littermates. Beige athymic (bg/bg nulnu) but not bg/bg nul+ mice developed cryptococcal lesions in the skin, demonstrating that C. neoformans is dermatotropic in a T-cell-deficient host. Higher numbers of C. neoformans were isolated from the lungs and spleen of infected bg/bg nulnu than bg/bg nul+ mice as early as day 3 after challenge, indicating that in lymphoid-rich organs, T cells can alter the course of systemic cryptococcosis early in the infection. Despite extensive abscess formation in the brains of bg/bg nu/+ mice, dissemination and growth rate of C. neoformans in the brain was similar in both genotypes. The primary histopathological feature in tissues from bg/bg nu/nu mice infected with C. neoformans consisted of foci of encapsulated yeast cells with minimal to no inflammatory response. In contrast to bg/bg nu/nu mice, bg/bg nu/+ mice mounted a vigorous inflammatory response to C. neoformans that progressed from acute to chronic inflammation. Beige athymic mice are a new animal model that will be useful in clarifying the innate and acquired immune factors important in resistance to cryptococcosis. Cryptococcus neoformans is an encapsulated yeast that causes pulmonary, central nervous system, or systemic disease in humans. A combination of innate and acquired immune responses is required to control this fungus in vivo. The high frequency of human exposure to C. neoformans in conjunction with the low incidence of cryptococcosis in the general population indicates that innate host defense mechanisms are relatively efficient in protecting against cryptococcal infection. Numerous in vitro studies have demonstrated that polymorphonuclear leukocytes (PMN), monocytes, and macrophages (MO) can ingest encapsulated

show abstract

Section: Discussionmentioning

confidence: 99%

Pathogenesis of Cryptococcus neoformans in congenitally immunodeficient beige athymic mice

Salkowski

Balish

1990

Infect Immun

View full text Add to dashboard Cite

show abstract

“…The anticryptococcal DTH response is positively influenced by a subset of CD4+ T cells termed Tamp cells. This can be demonstrated by injecting mice with Tamp cells at the time of immunization with CneF-CFA and observing 6 days later a significantly amplified DTH response in the recipient mice (6,7). To gain an understanding of what transpires during the expression phase of the amplified anticryptococcal DTH response, the gelatin sponge model for DTH (2) was used in this study.…”

Section: Resultsmentioning

confidence: 99%

“…Anticryptococcal CMI responses are induced by intranasal (2, 17) or intratracheal (11) infection with low numbers of C. neofornans or by immunization with CneF in complete Freund's adjuvant (CFA) (20, [27][28][29]. Immunization of mice induces cryptococcal-specific TDH cells, which are responsible for adoptive transfer of the anticryptococcal DTH response (12), and induces two regulatory T-cell populations (1,6,7,12).…”

mentioning

confidence: 99%

“…One of the regulatory T-cell populations found in the spleens of CneF-CFA-immunized mice is the Tamp cell (1, 6,7). Tamp cells get their name from the fact that when transferred to naive, syngeneic recipient mice at the time of immunization of the recipient, the Tamp cells significantly amplify the anticryptococcal DTH response which is detected 6 days after immunization of the recipient (1, 6, 7).…”

mentioning

confidence: 99%

“…Induction and elicitation of the amplified DTH response. The Tamp cells were induced by immunization with CneF-CFA as described previously (1,6,7). At 6 days after a subcutaneous immunization of mice, splenic cells were harvested as a source of Tamp cells (27).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Regulation of cytokine production during the expression phase of the anticryptococcal delayed-type hypersensitivity response

Buchanan

Murphy

1994

Infect Immun

Self Cite

View full text Add to dashboard Cite

Effects of both positive and negative regulatory T cells on cellular infiltration and cytokine production during the expression phase of the anticryptococcal immune response were examined. Tamp cells, which are induced by cryptococcal antigen, significantly amplify the anticryptococcal delayed-type hypersensitivity response, whereas a cascade of T suppressor (Ts) cells inhibits the response and decreases the clearance of Cryptococcus neoformans during an infection. By using the gelatin sponge implantation model, we found that Tamp cells do not stimulate a significant increase in cellular infiltration into the sponges in response to cryptococcal antigen compared with that into delayed-type hypersensitivity-reactive sponges in immune control mice. However, Tamp cells do stimulate significant increases in the production of gamma interferon and interleukin-2 (IL-2) in the antigen-injected sponges over the level of the representative cytokine in antigen-injected sponges from the immune control mice. Likewise, Tsl cells, induced with cryptococcal antigen, do not significantly affect antigen-induced cellular infiltration into sponges in immune mice. In contrast, decreased levels of gamma interferon and IL-2 are observed in antigen-injected sponges from Tsl-cell-recipient, immunized mice compared with those of the positive immune controls. The presence of either Tamp or Tsl cells in immunized mice stimulates increased production of IL-5 but not IL-4 over that of the positive immune controls.

show abstract

Cryptococcal Immunity and Immunostimulation

Murphy

1992

Microbial Infections

View full text Add to dashboard Cite

Characterization of a cell population which amplifies the anticryptococcal delayed-type hypersensitivity response

Cited by 16 publications

References 21 publications

Pathogenesis of Cryptococcus neoformans in congenitally immunodeficient beige athymic mice

Pathogenesis of Cryptococcus neoformans in congenitally immunodeficient beige athymic mice

Regulation of cytokine production during the expression phase of the anticryptococcal delayed-type hypersensitivity response

Cryptococcal Immunity and Immunostimulation

Contact Info

Product

Resources

About