title: Modulation of delayed-type hypersensitivity during the time course of immune response to a protein antigen.
abstract: Delayed-type hypersensitivity reactions elicited in the footpad of ovalbumin-sensitized mice after challenge with aggregated ovalbumin on day 4 or 8 of immunization are distinct. The former was characterized by a dense mononuclear infiltrate and, macroscopically, the reaction peaked at 48 hr after antigen challenge; the latter was preceded by immediate-type reactions, reached the maximum at 24 hr and faded drastically later. Histologically, oedema and a mixed granulocytic-lymphocytic infiltrate was found at this time-point. Immunoglobulin G1 (IgG1), IgG2a and IgE antibodies were detected only in plasma obtained after 8 days of immunization. Regarding the cytokines produced by draining lymph node cells after in vitro restimulation, interleukin-4 (IL-4) and IL-10 were predominant after 4 days and interferon-gamma and IL-2 after 8 days of immunization. These two types of delayed-type hypersensitivity (DTH) were used to study the influence of antibody-mediated responses on the inductive and effector phases of cell-mediated immunity. The effector phase of DTH was not affected by immediate-type reactions, as abrogation of these reactions by mediators' antagonists on day 8 or induction of passive reactions by transfer of immune serum on day 4 did not change the extent or kinetics of either type of DTH. Only transfer, before immunization, of whole or T-cell-enriched spleen cells, but not sera, from hyperimmunized donors (high antibody producers) abolished the induction of pure DTH in 4-day immunized recipient mice and changed their cytokine profile to a T helper 2 type. These results indicate that in a non-polarized immune response to a protein antigen there is initially a bias towards cell-mediated immunity, which is gradually dampened by the development of antibody-mediated immunity.
authors: Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors: J F
authors: JF
authors: Jacysyn
authors: I A
authors: IA
authors: Abrahamsohn
authors: M S
authors: MS
authors: Macedo
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology; D017690:Cell Transplantation; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D006968:Hypersensitivity, Delayed / Q000276:immunology*; D006969:Hypersensitivity, Immediate / Q000276:immunology; D007114:Immunization; D007116:Immunization, Passive; D007073:Immunoglobulin E / Q000096:biosynthesis; D007074:Immunoglobulin G / Q000096:biosynthesis; D051379:Mice; D008811:Mice, Inbred DBA; D010047:Ovalbumin / Q000276:immunology*; D012882:Skin Tests; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013997:Time Factors
chemical_list: D000941:Antigens; D016207:Cytokines; D007074:Immunoglobulin G; D007073:Immunoglobulin E; D010047:Ovalbumin