Abstract: The adhesin 170 kDa subunit of Hm-1:IMSS strain of Entamoeba histolytica is encoded by a gene family that includes hgl1, hgl2 and a previously undescribed third gene, hgl3, for which the DNA and protein sequences are disclosed. All three of these heavy subunit genes were expressed in the amebae. Methods and reagents (both nucleic acid and immunological) which are specific for each of the genes, as well as reagents which detect common regions of all three hgl genes or their nucleic acid or protein products, are disclosed. Recombinantly produced heavy chain subunit of E. Histolytica Gal/GalNAc adherence lectin or an epitope-bearing portion thereof may be used as antigen in serological analysis for E. histolytica infection or as an immunogen for protection against infection. Recombinant production in procaryotic systems provides antigens or immunogens which are immunologically reactive.

Abstract: A peptide compound having the sequence Lys-Pro-Ser-Ser-Pro-Pro-Glu-Glu [SEQ ID NO:2] or a substitution variant, addition variant or other chemical derivative thereof inhibits cell invasion, endothelial tube formation or angiogenesis in vitro. A number of substitution variants and addition variants of this peptide, preferably capped at the N- and C-termini, as well as peptidomimetic derivatives, are useful for treating diseases and conditions mediated by undesired and uncontrolled cell invasion and/or angiogenesis. Pharmaceutical compositions comprising the above peptides and derivatives are administered to subjects in need of such treatment in a dosage sufficient to inhibit invasion and/or angiogenesis. The disclosed compositions and methods are particularly useful for suppressing the growth and metastasis of tumors.