ANTI-HIV AND ANTITUMOR ACTIVITIES OF RECOMBINANT MAP30 FROM BITTER-MELON

MAP30 is an anti-HIV plant protein that we have identified and purifie d to homogeneity from bitter melon (Momordica charantia). It is capabl e of acting against multiple stages of the viral life cycle, on acute infection as well as replication in chronically infected cells. In add ition to antiviral action, MAP30 also possesses anti-tumor activity, t opological inactivation of viral DNA, inhibition of viral integrase an d cell-free ribosome-inactivation activities. We have cloned and expre ssed the MAP30 gene, The objective of this study is to characterize re combinant MAP30 (re-MAP30) and to determine its anti-HIV, anti-tumor a nd other activities. We report here that re-MAP30 inhibits HIV-1 and c ertain human tumors to the same extent as its native counterpart, natu ral MAP30 (nMAP30). The anti-HIV activity was measured by quantitative focal syncytium formation on CEM-ss cell monolayers, viral core prote in p24 expression and viral-associated reverse transcriptase activity in HIV-1-infected H9 cells. The anti-tumor activity was measured by me tabolic labeling of protein synthesis in tumor cells. In the dose rang e of the assay, re-MAP30 exhibits little toxicity to the uninfected vi ral target cells and other normal human cells. Identical to nMAP30, re -MAP30 is also active in topological inactivation of viral DNA, inhibi tion of viral DNA integration and cell-free ribosome inactivation. The cloning and expression of the gene encoding biologically active re-MA P30 provides an abundant source of homogeneous material for clinical i nvestigations, as well as structure-function studies of this novel ant iviral and anti-tumor agent.