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Abstract AIDS-associated, CCR5-tropic (R5) HIV-1 clones, isolated from a patient that never developed CXCR4-tropic HIV-1, replicate to a greater extent and cause greater cytopathic effects than R5 HIV-1 clones isolated before the onset of AIDS. Previously, we showed that HIV-1 Env substantially contributed to the enhanced replication of an AIDS clone. In order to determine if Nef makes a similar contribution, we cloned and phenotypically analyzed nef genes from a series of patient ACH142 derived R5 HIV-1 clones. The AIDS-associated Nef contains a series of residues found in Nef proteins from progressors 1. In contrast to other reports 123, this AIDS-associated Nef downmodulated MHC-I to a greater extent and CD4 less than pre-AIDS Nef proteins. Additionally, all Nef proteins enhanced infectivity similarly in a single round of replication. Combined with our previous study, these data show that evolution of the HIV-1 env gene, but not the nef gene, within patient ACH142 significantly contributed to the enhanced replication and cytopathic effects of the AIDS-associated R5 HIV-1 clone.

AIDS-associated, CCR5-tropic (R5) HIV-1 clones, isolated from a patient that never developed CXCR4-tropic HIV-1, replicate to a greater extent and cause greater cytopathic effects than R5 HIV- 1 clones isolated before the onset of AIDS. Previously, we showed that HIV- 1 Env substantially contributed to the enhanced replication of an AIDS clone. In order to determine if Nef makes a similar contribution, we cloned and phenotypically analyzed nef genes from a series of patient ACH142 derived R5 HIV- 1 clones. The AIDS-associated Nef contains a series of residues found in Nef proteins from progressors [1]. In contrast to other reports [1-3], this AIDS-associated Nef downmodulated MHC-I to a greater extent and CD4 less than pre-AIDS Nef proteins. Additionally, all Nef proteins enhanced infectivity similarly in a single round of replication. Combined with our previous study, these data show that evolution of the HIV- 1 env gene, but not the nef gene, within patient ACH142 significantly contributed to the enhanced replication and cytopathic effects of the AIDS-associated R5 HIV- 1 clone.

Chronic inflammation is linked to carcinogenesis in several organ systems. In the lungs, NF-[kappa]B, a central effector of inflammatory responses, is frequently activated in non-small-cell lung cancer, but its role in tumor promotion has not been studied. Several lines of evidence indicate that ethyl carbamate (urethane)-induced lung tumor formation, a prototypical mouse model of multistage lung carcinogenesis, is potentiated by inflammation. We found that mouse strains susceptible to lung tumor formation (FVB, BALB/c) exhibited early NF-[kappa]B activation and inflammation in the lungs after urethane treatment. However, a resistant strain (C57B6) failed to activate NF-[kappa]B or induce lung inflammation. In FVB mice, we identified urethane-induced NF-[kappa]B activation in airway epithelium, as well as type II alveolar epithelial cells and macrophages. Using an inducible transgenic mouse model (FVB strain) to express a dominant inhibitor of NF-[kappa]B specifically in airway epithelial cells, we found that urethane-induced lung inflammation was blocked and tumor formation was reduced by >50%. Selective NF-[kappa]B inhibition resulted in increased apoptosis of airway epithelial cells at 2 weeks after urethane treatment in association with a marked reduction of Bcl-2 expression. These studies indicate that NF-[kappa] apoptosis | cancer | inflammation | airway | adenocarcinoma

5'-(p-fluorosulfonylbenzoyl)-2'(or 3')-(methylanthraniloyl)adenosine (FSBMantAdo) is a specific affinity label for the epidermal growth factor (EGF) adenosine triphosphate (ATP) site. Introduction of 2' or 3' derivative of 5'-(p-fluorosulfonylbenzoyl) in the EGF receptor membrane vesicles leads to irreversible receptor kinase activity suppression. Incubation with a hydrolysis-resistant ATP analog, before FSBMantAdo treatment, protects the receptor kinase activity from FSBMantAdo inactivation. FSBMantAdo receptor-bound label exists in a relatively low polarity environment.

Studies the use of 5'-(p-fluorosulfonylbenzoyl)adenosine (5'-FSBAdo) and 5'(p-fluorosulfonylbenzoyl)-2'(or3') -(methylanthraniloyl)adenosine (FSBMantAdo) as fluorescent affinity labels for adenine nucleotide binding sites. Liquid secondary ionization mass spectrometry; Nuclear magnetic resonance (NMR) spectroscopy.