The present invention relates to chemically stable muteins of type 1 Placental Growth Factor (PLGF-1) bearing the substitution or elimination of a cysteine residue from the wild type protein amino acid sequence, their preparation, their therapeutic and cosmetic uses, and pharmaceutical and cosmetic compositions containing said derivatives. The invention likewise relates to the production of antibodies for said derivatives and their use in the diagnosis and treatment of tumoral and non-tumoral pathologies.