CD4+ T-lymphocyte

Metastatic renal cell carcinoma has a poor prognosis and resists conventional chemotherapy. Immunotherapy with IL-2 and/or IFN-a is currently regarded as the most effective therapy with, however, modest response rates of 15-20%. Similar results are also observed in patients with metastatic melanoma and the response to IFN-a and IL-2 correlates with the occurrence of tumor-infiltrating CD4+ T-lymphocytes identified in aspirates from melanoma metastases. Determination of these cells therefore seems to be a method to predict responders prior to the initiation of cytokine therapy. 

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... 

Macpherson JL, Boyd MP, Amdt AJ, Todd AV, Fanning GC, Ely JA, Elliott F, Knop A, Raponi M, Murray J, Gerlach W, Sun LQ, Penny R, Symonds GP, Carr A, Cooper DA (2005) Long-term survival and concomitant gene expression of ribozyme-transduced CD4 + T-lymphocytes in HIV-infected patients, J Gene Med 7 552-564... 

Ganesh L, Burstein E, Guha-Niyogi A, Louder MK, Mascola JR, Klomp LW, Wijmenga C, Duckett CS, Nabel GJ (2003) The gene product Murrl restricts HIV-1 rephcation in resting CD4-t lymphocytes. Nature 426(6968) 853-857... 

Peterson PK, Gekker G, Hu S, Cabral G, Lokensgard JR (2004) Cannabinoids and morphine differentially affect HIV-1 expression in CD4(-t) lymphocyte and microglial ceU cultures. J Neuroimmunol 147(1-2) 123-126... 

Human immunodeficiency virus (HIV) Differs from other retroviruses in that the core is cone-shaped rather than icosahedral HIV is transmitted from person to person via blood or genital secretions. The principal target for the virus is the CD4+ T-lymphocyte cells. Depletion of these cells induces immunodeficiency... 

Depending on the severity of immunosuppression (the CD4+ T lymphocyte count), patients may present with the following opportunistic infections (grouped by CD4+ count) ... 

Langenkamp A, Nagata K, Murphy K, Wu L, Lanzavecchia A, Sallusto F. Kinetics and expression patterns of chemokine receptors in human CD4+ T lymphocytes primed by myeloid or plasmacytoid dendritic cells. Eur J Immunol 2003 33 474 182. 

Tardif MR, Tremblay MJ. Presence of host ICAM-1 in human immunodeficiency virus type 1 virions increases productive infection of CD4+ T lymphocytes by favoring cytosolic delivery of viral material. J Virol 2003 77(22) 12299-12309. 

Davis, S.J., Ward, H.A., Puklavec, M.J. et al. (1990) High level expression in Chinese hamster ovary cells of soluble forms of CD4 T lymphocyte glycoprotein including glycosylation variants. The Journal of Biological Chemistry, 265 (18), 10410-10418. 

Karanu, F.N., McGuire, T.C., Davis, W.C., Besser, T.E. and Jasmer, D.P. (1997a) CD4+T lymphocytes contribute to protective immunity induced in sheep and goats by Haemonchus contortus gut antigens. Parasite Immunology 19, 435—145. 

Blotta, M.H., Marshall, J.D., De Kruyff, R.H. and Umetsu, D.T. (1996) Cross-linking of the CD40 ligand on human CD4+ T lymphocytes generates a co-stimulatory signal that upregulates IL-4 synthesis. Journal of Immunology 156, 3133-3140. 

Frandji, P., Tkaczyk, C., Oskeritzian, C., David, B., Desaymard, C. and Mecheri, S. (1996) Exogenous and endogenous antigens are differentially presented by mast cells to CD4+ T lymphocytes. European Journal of Immunology 26, 2517-2528. 

Progressive disease of AIDS 25-50e Amphotericin B 15-30 mg/kg (1 -2 g over 4-10 weeks/ or itraconazole 200 mg three times daily for 3 days then twice daily for 12 weeks, followed by lifelong suppressive therapy wilh ihaconazole 200-400 mg orally daily. Although patients receiving secondary prophylaxis (chronic maintenance therapy) might be at low risk for recurrence of systemic mycosis when their CD4+ T-lymphocyte counts increase to >100 cells/ microliter in response to HAART, the number of patents who have been evaluated is insufficient to warrant a recommendation to discontinue prophylaxis. 

HIV infection1 12 13 CD4+T lymphocyte count Diabetes, heart disease, chronic pulmonary disease, chronic alcoholism Asplenia12 (Including elective splenectomy and terminal complement component deficiencies) Chronic liver disease Kidney failure, end-stage renal disease, receipt of hemodialysis... 

The effects of Pb on the mixed lymphocyte response (MLR) have been examined in prior studies. McCabe and colleagues [53] and Farrer and colleagues [54] demonstrated that Pb in vitro at very low concentrations (0.1 pM = 2 pg/dL) significantly enhanced the proliferation and expansion of murine alloreactive CD4+ T lymphocytes in the MLR. The expanded T cell population was found to have a high density of CD4 molecules on the cell surface making them phenotypically similar to memory/effector T lymphocytes. In a study using Lewis strain rats, Razani-Boroujerdi and coworkers [55] also found evidence for Pb-induced stimulation of the in vitro MLR. 

CC - - TISSUE SPECIFICITY SPECIFICALLY EXPRESSED ON ACTI-CC VATED CD4+ T-LYMPHOCYTES. 

HIV-1 is the etiologic agent responsible for AIDS, a syndrome characterized by depletion of CD4+ T-lymphocytes and collapse of the immune system. People with AIDS are prone to opportunistic infections easily defended against by a normal immune system. Generally, it takes several years, post-infection, to progress to AIDS. 

Vendetti S, Patrizio M, Riccomi A, De Magistris MT Human CD4+ T lymphocytes with increased intracellular cAMP levels exert regulatory functions by releasing extracellular cAMP. J Leukoc Biol 2006 80 880-888. 

S, Albanesi C, Girolomoni G Human CD4+ T lymphocytes with remarkable regulatory functions on dendritic cells and nickel-specific Thl immune responses. J Invest Dermatol 2000 114 295-302. 

Sebastiani S, Allavena P, Albanesi C, Nasorri F, Bianchi G, Traidl C, Sozzani S, Girolomoni G, Cavani A Chemokine receptor expression and function in CD4+ T lymphocytes with regulatory activity. J Immunol2001 166 996-1002. 

Wittmann M, Alter M, Stunkel T, Kapp A, Werfel T Cell-to-cell contact between activated CD4+ T lymphocytes and unprimed monocytes interferes with a THl response. J Allergy Clin Immunol 2004 114 965-973. 

Tiede f Fritz G, Strand S et al. CD28-dependentRacl activation is the molecular target of azathioprine in primary human CD4+ T lymphocytes. JC/rw/wvesr2003 111 1133-1145. 

The pathogenesis of AIDS (10,12,13) following HIV infection may be separated into primary and secondary effects. The primary effects are (/) quantitative and qualitative decreases in infected cells, ie, the CD4+ T-lymphocytes (2) impaired cellular immunity (3) impaired immune surveillance and... 

Gradual diminution of CD4+ T-lymphocytes from the peripheral blood is the most consistent feature observed in HIV infection. Because the majority of CD4+ cells are T-helper lymphocytes, removal leads to deficiency of cellular immunity, which depends on T-helper cells to initiate cytotoxic T-cell killing of virus-infected cells of cancer. The loss of immune surveillance leads to the appearance of virally induced tumors from unopposed clonal expansion of vitally transformed cells. Furthermore, depletion of cellular immunity leads to exaggerated viral, fungal, and protozoal infections. 

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