Cellular and humoral immune responses to Pneumocystis carinii were investigated. ICR and DDD mice were intranasally infected with 10(4) mouse lung-derived P. carinii, and the delayed-type hypersensitivity (DTH) reaction and antibody titers to P. carinii were measured along with the number of P. carinii cysts in the lungs after infection. The number of P. carinii cysts in the lungs peaked at 2 w...

De novo expression of the interleukin 2 receptor (IL-2R) is a critical and pivotal event in initiation of an immune response. Targeting the low-affinity IL-2-binding p55 subunit of the high-affinity IL-2R with the rat anti-mouse IgM monoclonal antibody M7/20 suppresses a variety of T-cell-mediated reactions, including transplant rejection, autoimmunity, and delayed-type hypersensitivity (DTH). ...

Forkhead box P3 (FOXP3), which is a transcription factor, has a primary role in the development and function of regulatory T cells, and thus contributes to homeostasis of the immune system. A previous study generated a cell-permeable fusion protein of mouse FOXP3 conjugated to a protein transduction domain (PTD-mFOXP3) that successfully blocked differentiation of type 17 T helper cells in vitro...

PURPOSE To examine the effect of anti-LFA-1 and anti-ICAM-1 antibody treatment on orthotopic corneal graft survival in a mouse model. METHODS Anti-LFA-1 and anti-ICAM-1 antibodies were administered intraperitoneally before and shortly after orthotopic corneal transplantation. Grafts were observed by biomicroscopy, and survival times were determined. Cytotoxic T lymphocyte (CTL) and delayed-ty...

Culture conditions have been established that allow the induction of delayed-type hypersensitivity (DTH) precursor cells present in a cell population derived from unsensitized spleen cells only when antigen-specific, radioresistant, Thy-1-bearing helper cells are added. This specific cellular cooperation acts via the linked recognition of two determinants on the antigen; thus, cells primed to t...

Previously, we reported that Paracoccidioides brasiliensis culture filtrate antigen (Pb.Ag) when injected i.v. into mice induces antigen-specific suppressor cells which down-regulate the anti-P. brasiliensis delayed-type hypersensitivity (DTH) response. The suppressor cells are present in both spleens and lymph nodes of Pb.Ag-treated animals and suppress the afferent limb but not the efferent l...

BACKGROUND CD8(+) suppressor T cells exert antigen-specific suppression of the expression of hypersensitivity by activated T cells. Therefore, CD8(+) suppressor T cells serve a major regulatory role for the control of active immunity. Accordingly, the number and/or activity of CD8(+) suppressor T cells should be influenced by an immune response to the antigen. To test this hypothesis we used an...

Cryptococcosis, an increasingly important opportunistic infection caused by the encapsulated yeast-like organism Cryptococcus neoformans, is limited by an anticryptococcal cell-mediated immune (CMI) response. Gaining a thorough understanding of the complex anticryptococcal CMI response is essential for developing means of controlling infections with C. neoformans. The murine cryptococcosis mode...

Delayed-type hypersensitivity (DTH) to the azobenzenearsonate (ABA) hapten can be readily induced in A/J mice injecting ABA-coupled syngeneic spleen cells subcutaneously. To further characterize this T-cell-dependent immunological phenomenon, the effect of passively administered anti-cross-reactive idiotype common to anti-ABA antibodies of A/J mice (CRI) antibodies on the development of ABA-spe...

Mycobacterium intracellulare Mino grows progressively in the organs of C57BL/6 mice. When C57BL/6 mice were injected with strain Mino, very weak or almost no delayed-type hypersensitivity (DTH) to the specific antigen, M. intracellulare purified protein derivative, was observed. The DTH response was enhanced by cyclophosphamide pretreatment, indicating that some suppression mechanism(s) might b...