RT Journal Article SR Electronic(1) A1 Acevedo, Hernan F. A1 Pardo, Matias A1 Campbell-Acevedo, Elizabeth A1 Domingue, Gerald J.YR 1987 T1 Human Choriogonadotropin-like Material in Bacteria of Different Species: Electron Microscopy and Immunocytochemical Studies with Monoclonal and Polyclonal Antibodies JF Microbiology, VO 133 IS 3 SP 783 OP 791 DO https://doi.org/10.1099/00221287-133-3-783 PB Microbiology Society, SN 1465-2080, AB Immunocytochemical studies using antisera to whole human choriogonadotropin (hCG), to its α- and β-subunits and to the COOH-terminal peptide of hCGβ, and two monoclonal antibodies to hCGβ, demonstrated expression of hCG-like material, its individual subunits and/or fragments in nine bacterial strains. Seven of these were isolated from patients with cancer and were definitely identified as Streptococcus faecalis (three strains), Staphylococcus haemolyticus (two strains) and Staphylococcus epidermidis and Escherichia coli (single strains). The other two strains were cell-wall-deficient (CWD) variants, one identified as Streptococcus bovis, isolated from the blood of a patient with a fever of unknown origin and a possible brain abscess. The other was a Gram-negative diphtheroid isolated from the urine of a pregnant woman, which during the period of study reverted to a Gram-positive Corynebacterium identified as a ‘C. ulcerans’ strain and expressed the hCG-like factor only during its phase as Gram-negative diphtheroid. Electron microscopy of these nine strains (including negative controls of strains of the same species subjected to the same immunocytochemical analyses and under identical cultural conditions) revealed morphological alterations in the bacterial cell walls and cytoplasmic material and/or bizarre forms of reproduction in six of the nine strains expressing hCG-like material including the two CWD variants. Collectively, these results provided evidence that (1) hCG-producing bacteria isolated from patients with overt cancer are not a new and unique species as claimed by others, and (2) there is a close resemblance between the bacterial protein and the human trophoblastic hormone, based on immunochemical recognition of different parts of the hCG molecule. The morphological changes observed by electron microscopy may indicate that some of the bacteria expressing hCG-like material are revertants of CWD variants., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-133-3-783