Host responses

Lesion formation represents a host response to virus infection. Factors preventing the formation of starch lesions incited by the virus do not necessarily mean that virus replication is inhibited at the same time. Therefore, the total virus titer in cotyledon samples treated with different concentrations of tannic acid was determined (Figure... 

Cytokines and biological response modifiers represent a broad class of therapeutic agents that modify the hosts response to cancer or cancer therapies. The enormous body information about their clinical uses and their side effects is beyond the scope of this essay that can only give illustrative examples. For an up-to-date information the reader can resort to reference [5]. As many as 33 different interleukins are known and the list continues to grow IL-2 used in the treatment of kidney cancer is one example. Interferon alpha is used for chronic myelogenous leukeia, hairy cell leukaemia and Kaposi s sarcoma. Interferons are also used in the treatment of chronic infections such as viral hepatitis. Tumor necrosis factor (alpha), G/GM/M-CSF, and several other cellular factors are used in treatment of various cancers. Many of these cytokines produce serious side effects that limit their use. 

The development of sepsis is complex and multifactorial. The normal host response to infection is designed to localize and control bacterial invasion and initiate repair of injured tissue through phagocytic cells and inflammatory mediators.1 Sepsis... 

Tab. 2.3 Molecular determinants of microbial pathogenesis and host response...

B. Selected determinants of host response or susceptibility to microbial infection... 

Phalipon A, Sansonetti PJ Microbial-host interactions at mucosal sites. Host response to pathogenic bacteria at mucosal sites. Curr Top Microbiol Immunol 1999 236 163-189. 

Inflammation is the normal host response to infection or injury that mediates immune elimination of pathogens and tissue repair. Inflammatory processes include increased production of cytokines, chemokines, nitric oxide, and eicosanoids by the innate immune system in conjunction with altered leukocyte homing, all of which greatly impact acquired immunity. Aberrant inflammatory responses evoke both acute injury such... 

In utero exposure of mice to benzo(a)pyrene (B[a]P) resulted in suppression of the antibody response to SRBC, which persisted for up to 78 weeks in the offspring.102 In a follow up study, injection of B[a]P from gestation day 11 to 17 resulted in suppressed antibody responses to SRBC, MLR and graft versus host responses (GvH). It was suggested that lesions caused by B[a]P in the developing immune system may predispose the host to the growth of neoplasms.103... 

NO has complex roles in immunological host responses against viruses, and especially against HIV-1 infection. In HIV-1 infection, NO cannot be rigidly classified as an anti-inflammatory or proinflammatory molecule, but it can be deemed a true inflammatory mediator. Many studies support a proviral effect of NO in HIV-1 infection, mainly based on stimulation of viral replication, and on toxic effects on various cells, including central nervous system cells, via oxidative injury that may cause cellular and organ dysfunction, and immunosuppression and immunopathology, especially in the central nervous system. 

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