Inactivation of high-risk human papillomaviruses by Holder pasteurization: implications for donor human milk banking

Abstract

27 28 AIMS: Several studies have recently reported the detection of oncogenic human papillomaviruses 29 (HPV) in human milk of a minority of lactating mothers. These findings raised safety concerns in 30 the context of human donor milk banking given the potential risk of HPV transmission to recipient 31 infants. The aim of this study was to investigate whether the Holder pasteurization, a procedure 32 currently in use in human donor milk banks for milk pasteurization, completely inactivate high-risk 33 and low risk HPV. METHODS: HPV pseudoviruses (PsV) were generated, spiked into cell culture 34 medium or donor human milk and subjected to thermal inactivation. HPV PsV infectivity and 35 morphological integrity was analyzed by cell-based assay and by electron microscopy respectively. 36 RESULTS: The Holder pasteurization completely inactivated the infectivity of high-risk (types 16 37 and 18) and low-risk (type 6) HPV both in cell culture medium and in human milk causing PsV 38 particles disassembly. CONCLUSIONS: The results presented here indicate that the Holder 39 pasteurization is an efficient procedure to inactivate high-risk and low-risk HPV thus preventing the 40

High-Temperature Short-Time Pasteurization System for Donor Milk in a Human Milk Bank Setting

“…At present, a Low-Temperature Long-Time (heating at 62.5°C for 30 min) pasteurization, also known as “Holder” pasteurization (HoP), is the heat treatment most commonly applied to DHM. High-risk viruses, such as cytomegalovirus, papillomaviruses, and human immunodeficiency, T-lymphotrophic, Ebola, Marburg, and Zika viruses, are also destroyed after HoP of human milk (Orloff et al, 1993 ; Chiavarini et al, 2011 ; Rigourd et al, 2011 ; Donalisio et al, 2014 ; Hamilton Spence et al, 2017 ; Pfaender et al, 2017 ) while spore-forming bacteria, such as Bacillus sp., may survive this heating process (de Segura et al, 2012 ). On the other hand, some nutritional and biological components, such as immunoglobulins, hormones or enzymes, result negatively affected after HoP (Peila et al, 2016 ).…”

Frequência do Papilomavírus Humano na placenta, no colostro e no sangue do cordão umbilical

“…A transmissão do HPV através do aleitamento materno ainda não está estabelecida [12][13][14] . Apesar da hipótese de que essa transmissão pode não ocorrer porque o HPV não provoca viremia 13 , já foi observado que o HPV encontrado no leite materno pode estar viável e infectante 22 . Estudar novas formas de transmissão do HPV como pelo banco de leite e pelo transplante de células totipotentes do cordão umbilical é importante na elaboração de medidas que interrompam a cadeia de transmissão.…”

High Temperature—Short Time Pasteurization Has a Lower Impact on the Antiviral Properties of Human Milk Than Holder Pasteurization

“…HSV-1, HSV-2, and HRhV titers were determined by the standard plaque method and expressed as plaque-forming unit (PFU)/ml. A bacterial artificial chromosome (BAC)-derived HCMV strain Towne incorporating the green fluorescent protein (GFP) sequence ( 23 ) was propagated on HFF-1 and viral titres were determined by fluorescent focus assay. RSV strain A2 (ATCC VR-1540) was propagated in Hep-2 and titrated by the indirect immunoperoxidase staining procedure using an RSV monoclonal antibody (Ab35958, Abcam) ( 24 ).…”