Immunity has been considered one of the most specific of biologic reactions and it has been assumed that an infection induced by one organism within a closely related group does not immunize against another organism of the same group. The recent studies of Weil, Felix, and Olitzki suggest strongly that there is a group immunity between typhoid and enteritidis infections. The results here report...

1. Animals showing natural bacterial allergy to filtrates of B. lepisepticum survive infection by this organism more frequently than weak reactors. This increased resistance is manifested by better localization of infection. 2. Bacterial filtrates injected into skin 24 hours before infection exert a non-specific protection of that area against the organism, even in susceptible animals. The cell...

BACKGROUND Cellular immunity is the main defense mechanism in paracoccidioidomycosis (PCM), the most important systemic mycosis in Latin America. Th1 immunity and IFN-γ activated macrophages are fundamental to immunoprotection that is antagonized by IL-10, an anti-inflammatory cytokine. Both in human and experimental PCM, several evidences indicate that the suppressive effect of IL-10 causes de...

Treatments which heighten the immune response can inhibit tumor growth in susceptible hosts. For example, BCG administered with tumor cells or injected into established intradermal tumors (1, 2) resulted in specific, systemic tumor immunity in guinea pigs. These procedures, however, depended upon direct contact of BCG and tumor cells; contralateral challenges were less effective (3). Another ap...

• The cells of the immune system are divided into lymphoid and myeloid lineages. The former include T lymphocytes and their subsets identified by CD markers, B lymphocytes and natural killer (NK) cells. The myeloid lineage includes the neutrophils, eosinophils and basophils as well as the monocyte/ macrophage series and platelets. • Innate immunity depends on physical, physiological and chemica...

Acute stressors (lasting minutes) were associated with potentially adaptive up regulation of some parameters of natural immunity and down regulation of some functions of specific immunity. Brief naturalistic stressors (such as exams) tended to suppress cellular immunity while preserving humoral immunity. Chronic stressors were associated with suppression of both cellular and humoral measures. V...

Cell-mediated immunity in vivo results in allograft destruction, in graft versus host reactions following bone marrow transplantation, in delayed type hypersensitivity responses to mycobacteria and other antigens, in autoimmune or autoaggressive diseases and in immunity to tumors, allogeneic or syngeneic.1.2 Natural cellular immunity-also known as cellular natural killing (CNK)-has been describ...

BACKGROUND Leprosy, a chronic granulomatous disease affecting the skin and nerves, is caused by Mycobacterium leprae (M. leprae). The type of leprosy developed depends upon the host immune response. Type 1 reactions (T1Rs), that complicate borderline and lepromatous leprosy, are due to an increase in cell-mediated immunity and manifest as nerve damage and skin inflammation. Owing to the increas...

the plant-pathogen interaction is a multifactor process that may lead to resistance or susceptible responses of plant to pathogens. during the arms race between plant and pathogens, various biochemical, molecular and physiological events are triggered in plant cells such as ros signaling, hormone activation and gene expression reprogramming. in plants, micrornas (mirnas) are key post-transcript...

To examine the immunopathogenesis of type 2 erythema nodosum leprosum (ENL) reactions in leprosy, we studied cellular and soluble immunologic components of skin lesions in 57 patients with reactions (19 acute ENL and 38 chronic ENL), 61 active patients without reactions, and 33 control patients whose leprosy had been treated and cured. Cells, IgM antibody to PGL-1 and Tac peptide levels were ob...