Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The need for agents designed to modify immune response in the treatment of patients with viral infection, immunodeficiency, or cancer prompted the present study on the mechanisms of action of isoprinosine, a compound developed for antiviral use and whose therapeutic activity may involve the immune system. The effect of isoprinosine on in vitro proliferation of human peripheral blood lymphocytes stimulated by phytohemagglutinin (PHA) and on lymphocyte levels of cyclic adenosine 3',5'-monophosphate and cyclic guanosine 3',5'-monophosphate was analyzed. Over a concentration range from 0.2 to 250 mug/ml, isoprinosine augmented PHA-induced proliferation; maximal stimulation was observed between 25 to 50 mug/ml. Isoprinosine in the absence of PHA had no effect on proliferation. The relative lack of effect of isoprinosine during a 90-min exposure and the lack of effect on lymphocyte cyclic nucleotide levels indicate that isoprinosine potentiates the PHA response by a mechanism different than a number of hormonal agents and such immunopotentiators as levamisole, polyadenylic-acid, and endotoxin. Further evaluation of isoprinosine as an immunopotentiator is indicated.
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PMID:Isoprinosine augmentation of phytohemagglutinin-induced lymphocyte proliferation. 5

The efficacy of antifolate, antiviral, and other drugs was compared in an experimental model of pneumocystosis. Sulfamethoxazole (SMX) administered alone in doses of greater than or equal to 60 mg/kg/day was highly effective in treatment and prophylaxis. Low (less than or equal to 15 mg/kg/day) doses of SMX showed limited, dose-related anti-Pneumocystis carinii activity in therapy but were more effective in prophylaxis. The dihydrofolate reductase (DHFR) inhibitors trimethoprim (TMP), pyrimethamine, and trimetrexate exhibited little anti-P. carinii activity when administered alone and did not enhance the efficacy of SMX; the effects of the DHFR inhibitors could not be related to the dose or the concentration in serum. These data suggested that the rat model is an excellent system for studying the anti-P. carinii activity of sulfonamides but is of limited value in studying DHFR inhibitors. The antiviral drugs azidothymidine, dideoxyinosine, inosine pranobex (Isoprinosine), amantadine, and acyclovir displayed little or no activity against P. carinii; however, azidothymidine did not impair the efficacy of SMX or TMP-SMX. These results supported the clinical practice of giving antiviral agents together with antifolate drugs to patients infected with human immunodeficiency virus and suggested that the beneficial effects of antiviral agents on the occurrence of pneumocystosis are due mainly to their effects on the virus or the host immune response. In contrast to the antiviral drugs, 9-deazainosine, a nucleoside analog with antiprotozoal properties, demonstrated marked activity against P. carinii which was related to dose and route of administration. These data raised the possibility that anti-P. carinii activity is a general property of purine nucleosides and suggested that further exploration of this class of compounds might lead to clinically useful agents.
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PMID:Activities of antifolate, antiviral, and other drugs in an immunosuppressed rat model of Pneumocystis carinii pneumonia. 141 84

We performed a randomized, double-blind, placebo-controlled trial to assess the efficacy and safety of inosine pranobex (Isoprinosine) [corrected] in the treatment of patients with human immunodeficiency virus (HIV) infection but without manifest acquired immunodeficiency syndrome (AIDS). A total of 866 patients were enrolled in 21 centers in Denmark and Sweden. The patients were stratified in three groups according to their CD4+ cell count and randomly assigned to receive either inosine pranobex (1 g three times a day) (n = 429) or matching placebo (n = 437) for 24 weeks. Of the 831 patients who could be evaluated, AIDS developed in 17 in the placebo group as compared with 2 in the inosine pranobex group (P less than 0.001; odds ratio, 8.6 [95 percent confidence limits, 2.2 and 52.6]). There were no significant differences between the groups with respect to changes in CD4+ cell count or the development of other HIV-related conditions, with the exception of thrush, which developed in fewer patients in the inosine pranobex group (P = 0.05). No serious side effects were observed. We conclude that treatment with inosine pranobex delays progression to AIDS in patients with HIV infection. The duration of this beneficial effect, the optimal dose, and the mode of action of inosine pranobex remain to be clarified.
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PMID:The efficacy of inosine pranobex in preventing the acquired immunodeficiency syndrome in patients with human immunodeficiency virus infection. The Scandinavian Isoprinosine Study Group. 170 81

The immunopharmacologic effects of Isoprinosine (INPX) have been associated with clinical benefit to the patient in a number of conditions characterized by immunodeficiency of diverse etiology. Immunodepressed homosexuals at risk of developing acquired immunodeficiency syndrome (AIDS) treated with placebo or INPX experienced an increase in the function and number of immunocompetent cells associated with clinical improvement. A multicenter trial designed to confirm these results has demonstrated that INPX produced an increase in natural killer (NK)-cell activity, total T cells, and T-helper cells, with certain effects persisting for months after completion of the 28-day treatment period. INPX-treated patients also experienced clinical improvement and decreased incidence of progression to AIDS. The administration of INPX for longer periods to patients with frank AIDS under a compassionate-use protocol has also proved useful. Clinical benefit associated with INPX treatment has been demonstrated in other patients with a depressed immune response, such as aged patients, cancer patients, severely burned patients, ill patients, and surgery patients. This program of clinical trials supports the therapeutic use of INPX in the treatment of AIDS and other acquired immunodeficiencies of clinical importance.
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PMID:Isoprinosine (inosine pranobex BAN, INPX) in the treatment of AIDS and other acquired immunodeficiencies of clinical importance. 244 60

Since clinical trials are being planned with the immunomodulating drug isoprinosine combined with the antiviral drug 3'-azido-3'-deoxythymidine (AZT) in patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex, it is important to determine the type of antiviral interaction produced by these drugs in vitro. Such a combined modality may not only produce enhanced antiviral effects but also may have a valuable immunorestorative action. The interaction of several ratios of AZT and isoprinosine on the replication of human immunodeficiency virus type 1 in human peripheral blood mononuclear cells was determined by reverse transcriptase assay of disrupted virus obtained from supernatants of cells that were exposed to virus and the drugs separately and in combination and by a human immunodeficiency virus type 1 p24 enzyme immunoassay of the same supernatants. The correlation between the reverse transcriptase and enzyme immunoassay data was high. The antiviral activity of AZT alone was neither diminished nor augmented when AZT was used in combination with isoprinosine. Isoprinosine did not enhance virus yield when used alone or in combination with AZT in peripheral blood mononuclear cells, nor did it affect the growth of uninfected cells. The in vitro results indicate that this combination did not decrease the efficacy of AZT or exacerbate virus replication.
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PMID:Combinations of isoprinosine and 3'-azido-3'-deoxythymidine in lymphocytes infected with human immunodeficiency virus type 1. 246 87

Isoprinosine may delay disease progression in human immunodeficiency virus infection, presumably through modulation of lymphocyte function. However, the influence of isoprinosine on phagocyte function is largely unknown. This study describes the effects of isoprinosine and azidothymidine on phagocyte chemiluminescence and migration. Incubation with isoprinosine concentrations of 250 micrograms/ml and above increased the chemiluminescence of granulocytes. Random migration of granulocytes was decreased at isoprinosine concentrations of 50 micrograms/ml and higher, but chemotaxis was not affected. Azidothymidine exerted no effect on the chemiluminescence or migration of granulocytes. For monocytes, luminol-enhanced chemiluminescence was reduced at isoprinosine concentrations of 250 micrograms/ml and above, whereas migration was not affected. These findings suggest that the immunomodulatory properties of isoprinosine may extend to phagocytic cells. This may be of significance in the treatment of immunodeficiency states.
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PMID:Isoprinosine stimulates granulocyte chemiluminescence and inhibits monocyte chemiluminescence in vitro. 751 72

Isoprinosine has been reported to decrease progression to AIDS, primarily by preventing Pneumocystis carinii pneumonia (PCP), in human immunodeficiency virus-infected patients, but the mechanism of action is unknown. para-Acetamidobenzoic acid (PAcBA), one component of isoprinosine, is structurally related to para-aminobenzoic acid (PABA), a precursor of de novo folate synthesis. This pathway is known to be important for P. carinii because sulfonamides, which are effective anti-P. carinii agents, inhibit incorporation of PABA into folate precursors by the enzyme dihydropteroate synthetase (DHPS). Inhibition of P. carinii DHPS by PAcBA was investigated by using two assays. In short-term cultures of P. carinii from rats, [3H]PABA incorporation into reduced folates was inhibited by both isoprinosine (mean +/- standard error 50% inhibitory concentration [IC50], 20 +/- 8.4 microM) and PAcBA free acid (IC50, 240 +/- 100 microM); a soluble PAcBA salt was more potent than PAcBA free acid alone (IC50, 29 +/- 48 microM). The activity of PAcBA free acid was confirmed in a cell-free DHPS inhibition assay (IC50, 120 +/- 120 microM). Inosine and dimethylaminopropanol, two other components of isoprinosine, were poor inhibitors of PABA incorporation (IC50, > 1,000 microM). PAcBA free acid also showed activity in inhibiting the DHPS of Toxoplasma gondii, but was a poor inhibitor of the DHPSs of Escherichia coli and Saccharomyces cerevisiae. In a rat model of PCP, the PAcBA salt administered intraperitoneally demonstrated no activity against established PCP either alone or when used in combination with trimethoprim; the lack of efficacy in this model may be due to the rapid metabolism of the drug. Prevention of PCP by PaCBA through inhibition of P. carinii DHPS may explain the activity of isoprinosine in decreasing the progression to AIDS in human immunodeficiency virus-infected patients.
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PMID:Inhibition of Pneumocystis carinii dihydropteroate synthetase by para-acetamidobenzoic acid: possible mechanism of action of isoprinosine in human immunodeficiency virus infection. 768 20

Inosine pranobex (IP), commonly known as inosine acedoben dimepranol, isoprinosine and methisoprinol, has been proven to positively impact the host's immune system, by enhancing T-cell lymphocyte proliferation and activity of natural killer cells, increasing levels of pro-inflammatory cytokines, and thereby restoring deficient responses in immunosuppressed patients. At the same time, it has been shown that it can affect viral RNA levels and hence inhibit growth of several viruses. Due to its immunomodulatory and antiviral properties, and its safety profile, it has been widely used since 1971 against viral infections and diseases, among which subacute sclerosis panencephalitis, herpes simplex virus, human papilloma virus, human immunodeficiency virus, influenza and acute respiratory infections, cytomegalovirus and Epstein-Barr virus infections. Following an analysis of almost five decades of scientific literature since its original approval, we here summarize in vivo and in vitro studies manifesting the means in which IP impacts the host's immune system. We also provide a synopsis of therapeutic trials in the majority of which IP was found to have a beneficial effect. Lastly, positive results from limited studies, suggesting the putative future use of IP in new therapeutic indications are briefly described. In order to support use of IP against viral infections apart from those already approved, and to establish its use in clinical practice, further well-designed and executed trials are warranted.Funding: Ewopharma International.
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PMID:Inosine Pranobex: A Key Player in the Game Against a Wide Range of Viral Infections and Non-Infectious Diseases. 3116 64