Viruses lymphocytes

Maeda H, Katsuki T, Akaike T and Yasutake R. 1992. High correlation between lipid peroxide radical and tumor-promoter effect—suppression of tumor promotion in the Epstein-Barr-virus lymphocyte-B system and scavenging of alkyl peroxide radicals by various vegetable extracts. Jpn J Cancer Res 83(9) 923-928. 

Arenavirus (Lassa fever virus, lymphocytic choriomeningitis virus, Machupo virus, and Junin virus). Enveloped, helical, ambisense, and ssRNA (two segments). Synthesis occurs in the host cell cytoplasm maturation involves budding from the host cell plasma membrane. Virions contain ribosomes. The human pathogens Lassa, Machuppo, and Junin viruses are Biosafety Level 4 pathogens - they must be handled in the laboratory under maximum containment conditions. 

Travis WD, Fox CH, Devaney KO, et al. Lymphoid pneumonitis in 50 adult patients infected with the human immunodeficiency virus lymphocytic interstitial pneumonitis versus nonspecific interstitial pneumonitis. Hum Pathol 1992 23 529-541. 

Arenavirus (Lassa fever virus, lymphocytic choriomeningitis virus, Machupo virus, Junin virus)... 

The viruses responsible for AIDS are human immunodeficiency virus 1 and 2 (HIV 1 and HIV 2) Both are retroviruses, meaning that their genetic material is RNA rather than DNA HI Vs require a host cell to reproduce and the hosts m humans are the T4 lymphocytes which are the cells primarily responsible for inducing the immune system to respond when provoked The HIV penetrates the cell wall of a T4 lymphocyte and deposits both its RNA and an enzyme called reverse transcriptase inside There the reverse transcriptase catalyzes the formation of a DNA strand that is complementary to the viral RNA The transcribed DNA then serves as the template from which the host lymphocyte produces copies of the virus which then leave the host to infect other T4 cells In the course of HIV reproduction the ability of the T4 lymphocyte to reproduce Itself IS compromised As the number of T4 cells decrease so does the body s ability to combat infections... 

Human Immunodeficiency Virus. Human immunodeficiency vims (HIV) causes Acquired Immunodeficiency Syndrome (AIDS), which has no cure. HIV infects the cells of the human immune system, such as T-lymphocytes, monocytes, and macrophages. After a long period of latency and persistent infection, it results in the progressive decline of the immune system, and leads to full-blown AIDS, resulting in death. 

Interferons [alFN, piFN and ylFN]. Interferons are a family of glycosylated proteins and are cytokines which are produced a few hours after cells have been infected with a virus. Interferons protect cells from viral infections and have antiviral activities at very low concentrations ( 3 x 10 M, less than 50 molecules are apparently sufficient to protect a single cell). Double stranded RNA are very efficient inducers of IFNs. There are three main types of IFNs. The aIFNs are synthesised in lymphocytes and the piFNs are formed in infected fibroblasts. The a and P families are fairly similar consisting of ca 166 to 169 amino acids. Although ylFNs are also small glycosylated proteins (ca 146 amino acids), they are different because they are not synthesised after viral infections but are produced by lymphocytes when stimulated by mitogens (agents that induced cell division). 

In this type of reaction an antigen elicits the generation of cytotoxic T-lymphocytes ( immune defense). Cytotoxic T-lymphocytes (Tc) destroy antigen bearing cells by inducing apoptosis. This reaction can be viewed as the cellular counterpart to the humoral Type II reactions. They play an important physiological role in the defense of viruses, and can become allergic reactions under the same conditions as described for Type II reactions. 

For the pathogenesis of multiple sklerosis, autoimmune T-lymphocy tes play a predominant role, which are directed against components of the neural myelin sheath. T-lymphocy tes by secreting cytokines such as interferon y maintain the chronic inflammation which destructs the myelin sheath. Also cytotoxic T-lymphocytes may participate directly. The cause of multiple sklerosis is unknown. Significantly increased antibody titers against several vitusses, mostly the measles virus, point to a (latent) virus infection initiating the disease. 

Double stranded (ds) RNA is not a constituent of a normal cells but is produced during replication of many RNA and DNA viruses either as an obligatory intermediate or as a side product. As a foreign molecule, double stranded RNA induce the secretion of interferon (EFN) from lymphocytes, neutrophils and fibroblasts. 

Retroviruses Human T-cell leukemia virus (HTLV) Human T-lymphocytic tumors... 

Karlsson GB, Halloran M, Schenten D, Lee J, Racz P, Tenner-Racz K, Manola J, Gelman R, Etemad-Moghadam B, Desjardins E, Wyatt R, Gerard NP, Marcon L, Margolin D, Fanton J, Axthelm MK, Letvin NL, Sodroski J (1998) The envelope glycoprotein ectodomains determine the efficiency of CD4+ T lymphocyte depletion in simian- human immunodeficiency virus-infected macaques. J Exp Med 188 1159-1171... 

Fernie BF, Poli G, Fauci AS (1991) Alpha interferon suppresses virion but not soluble human immunodeficiency virus antigen production in chronically infected T-lymphocytic cells. J Virol 65 3968-3971... 

Baltimore D (1988) Gene therapy. Intracellular immunization. Nature 335 395-396 Basta S, Stoessel R, Easier M, van den Broek M, Groettrup M (2005) Cross-presentation of the long-lived lymphocytic choriomeningitis virus nucleoprotein does not require neosynthesis and is enhanced via heat shock proteins. J Immunol 175 796-805 Baum C (2007) Insertional mutagenesis in gene therapy and stem cell biology. Curr Opin Hematol 14 337-342... 

Cooper LJ, Kalos M, Lewinsohn DA, Riddell SR, Greenberg PD (2000) Transfer of specificity for human immunodeficiency virus type 1 into primary human T lymphocytes by introduction of T-cell receptor genes. J Virol 74 8207-8212... 

Richardson JH, Child LA, Lever AM (1993) Packaging of human immunodeficiency virus type 1 RNA requires cis-acting sequences outside the 5 leader region, J Virol 67 3997 005 Roberts MR, Qin L, Zhang D, Smith DH, Tran AC, Dull TJ, Groopman JE, Capon DJ, Bym RA, Finer MH (1994) Targeting of human immunodeficiency virus-infected cells by CD8-I- T lymphocytes armed with universal T-cell receptors. Blood 84 2878-2889 Rooney CM, Smith CA, Ng CY, Loftin S, Li C, Krance RA, Brenner MK, Heslop HE (1995) Use of gene-modified virus-specific T lymphocytes to control Epstein-Barr-virus-related lympho-proliferation. Lancet 345 9-13... 

Schmitz JE, Kuroda MJ, Santra S, Sasseville VG, Simon MA, lifton MA, Racz P, Tenner-Racz K, Dalesandro M, Scallon BJ, Ghrayeb J, Forman MA, Montefioii DC, Richer EP, Letvin NL, Reimann KA (1999) Control of viremia in simian immunodeficiency virus infection by CD8+ lymphocytes. Science 283 857-860... 

Walker CM, Levy JA (1989) A diffusible lymphokine produced by CD8+ T lymphocytes suppresses HIV replication. Immunology 66 628-630 Walker RE, Bechtel CM, Natarajan V, Baseler M, Hege KM, Metcalf JA, Stevens R, Hazen A, Blaese RM, Chen CC, Lehman SF, Palensky J, Wittes J, Davey RT, Falloon J, Polls MA, Ko-vacs JA, Broad DF, Levine BL, Roberts MR, Masur H, Lane HC (2000) Long-term in vivo survival of receptor-modified syngeneic T cells in patients with human immunodeficiency virus infection. Blood 96 467 74... 

The 2 -chloro and 2 -bromo congeners of either 748 (FIAC) or 758 (FMAU) are more cytotoxic than FIAC and FMAU, suggesting that these chloro and bromo nucleosides, in contrast to the 2 -fluoro compounds, are comparatively better substrates for deoxycytidine kinase of human lymphocytes than the substrates for viral-specific thymidine kinase. The disposition of the 2 -fluoro group may also be important from the biological viewpoint. It should be noted that the structural difference between RNA and DNA is at the 2 -position. The ribo type of analog (738) of FIAC is 10 times less effective in suppression of HSV replication than is FIAC. Thus Fox, and Watanabe and coworkers concluded that the 2 - up fluorine disposition and the species of the substituent at C-5 are the two important factors influencing antiviral activity. Nevertheless, the mechanism of action of 2 -deoxy-2 -fluorocytidine (737) on certain herpes viruses, including HSV-1... 

HIV strains are grouped according to the preferred site of replication. T-tropic viruses prefer replication in T lymphocytes and M-tropic viruses in macrophages. Use of chemokine receptors differs for each subgroup CXCR4 (or fusin, the receptor for stromal cell-derived factor [SDF-1]) for T-tropic viruses and CCR5 (the receptor... 

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