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Hernandez AS, Zayas GA, Rodriguez EE, Sarlo Davila KM, Rafiq F, Nunez AN, Titto CG, Mateescu RG. Exploring the genetic control of sweat gland characteristics in beef cattle for enhanced heat tolerance. J Anim Sci Biotechnol 2024; 15:66. [PMID: 38715151 PMCID: PMC11077762 DOI: 10.1186/s40104-024-01025-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 03/11/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Thermal stress in subtropical regions is a major limiting factor in beef cattle production systems with around $369 million being lost annually due to reduced performance. Heat stress causes numerous physiological and behavioral disturbances including reduced feed intake and decreased production levels. Cattle utilize various physiological mechanisms such as sweating to regulate internal heat. Variation in these traits can help identify genetic variants that control sweat gland properties and subsequently allow for genetic selection of cattle with greater thermotolerance. METHODS This study used 2,401 Brangus cattle from two commercial ranches in Florida. Precise phenotypes that contribute to an animal's ability to manage heat stress were calculated from skin biopsies and included sweat gland area, sweat gland depth, and sweat gland length. All animals were genotyped with the Bovine GGP F250K, and BLUPF90 software was used to estimate genetic parameters and for Genome Wide Association Study. RESULTS Sweat gland phenotypes heritability ranged from 0.17 to 0.42 indicating a moderate amount of the phenotypic variation is due to genetics, allowing producers the ability to select for favorable sweat gland properties. A weighted single-step GWAS using sliding 10 kb windows identified multiple quantitative trait loci (QTLs) explaining a significant amount of genetic variation. QTLs located on BTA7 and BTA12 explained over 1.0% of genetic variance and overlap the ADGRV1 and CCDC168 genes, respectively. The variants identified in this study are implicated in processes related to immune function and cellular proliferation which could be relevant to heat management. Breed of Origin Alleles (BOA) were predicted using local ancestry in admixed populations (LAMP-LD), allowing for identification of markers' origin from either Brahman or Angus ancestry. A BOA GWAS was performed to identify regions inherited from particular ancestral breeds that might have a significant impact on sweat gland phenotypes. CONCLUSIONS The results of the BOA GWAS indicate that both Brahman and Angus alleles contribute positively to sweat gland traits, as evidenced by favorable marker effects observed from both genetic backgrounds. Understanding and utilizing genetic traits that confer better heat tolerance is a proactive approach to managing the impacts of climate change on livestock farming.
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Affiliation(s)
- Aakilah S Hernandez
- Department of Animal Science, North Carolina State University, Raleigh, NC, USA
| | - Gabriel A Zayas
- Department of Animal Sciences, University of Florida, Gainesville, FL, USA
| | | | - Kaitlyn M Sarlo Davila
- Ruminant Diseases and Immunology Research Unit, National Animal Disease Centers, United States Department of Agriculture, 1920 Dayton Avenue, Ames, IA, 50010, USA
| | - Fahad Rafiq
- Department of Animal Sciences, University of Florida, Gainesville, FL, USA
| | | | - Cristiane Gonçalves Titto
- School of Animal Sciences and Food Engineering, University of São Paulo, Av Duque de Caxias Norte 225, Pirassununga, Sao Paulo, 13635-900, Brazil
| | - Raluca G Mateescu
- Department of Animal Sciences, University of Florida, Gainesville, FL, USA.
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Hlongwane NL, Dzomba EF, Hadebe K, van der Nest MA, Pierneef R, Muchadeyi FC. Identification of Signatures of Positive Selection That Have Shaped the Genomic Landscape of South African Pig Populations. Animals (Basel) 2024; 14:236. [PMID: 38254405 PMCID: PMC10812692 DOI: 10.3390/ani14020236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 12/17/2023] [Accepted: 01/10/2024] [Indexed: 01/24/2024] Open
Abstract
South Africa boasts a diverse range of pig populations, encompassing intensively raised commercial breeds, as well as indigenous and village pigs reared under low-input production systems. The aim of this study was to investigate how natural and artificial selection have shaped the genomic landscape of South African pig populations sampled from different genetic backgrounds and production systems. For this purpose, the integrated haplotype score (iHS), as well as cross population extended haplotype homozygosity (XP-EHH) and Lewontin and Krakauer's extension of the Fst statistic based on haplotype information (HapFLK) were utilised. Our results revealed several population-specific signatures of selection associated with the different production systems. The importance of natural selection in village populations was highlighted, as the majority of genomic regions under selection were identified in these populations. Regions under natural and artificial selection causing the distinct genetic footprints of these populations also allow for the identification of genes and pathways that may influence production and adaptation. In the context of intensively raised commercial pig breeds (Large White, Kolbroek, and Windsnyer), the identified regions included quantitative loci (QTLs) associated with economically important traits. For example, meat and carcass QTLs were prevalent in all the populations, showing the potential of village and indigenous populations' ability to be managed and improved for such traits. Results of this study therefore increase our understanding of the intricate interplay between selection pressures, genomic adaptations, and desirable traits within South African pig populations.
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Affiliation(s)
- Nompilo L. Hlongwane
- Agricultural Research Council, Biotechnology Platform, Private Bag X5, Onderstepoort 0110, South Africa; (K.H.); (R.P.); (F.C.M.)
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, South Africa;
| | - Edgar F. Dzomba
- Discipline of Genetics, School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, South Africa;
| | - Khanyisile Hadebe
- Agricultural Research Council, Biotechnology Platform, Private Bag X5, Onderstepoort 0110, South Africa; (K.H.); (R.P.); (F.C.M.)
| | - Magriet A. van der Nest
- Agricultural Research Council, Biotechnology Platform, Private Bag X5, Onderstepoort 0110, South Africa; (K.H.); (R.P.); (F.C.M.)
- Hans Merensky Chair in Avocado Research, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa;
| | - Rian Pierneef
- Agricultural Research Council, Biotechnology Platform, Private Bag X5, Onderstepoort 0110, South Africa; (K.H.); (R.P.); (F.C.M.)
- Department of Biochemistry, Genetics and Microbiology, University of Pretoria, Pretoria 0002, South Africa
| | - Farai C. Muchadeyi
- Agricultural Research Council, Biotechnology Platform, Private Bag X5, Onderstepoort 0110, South Africa; (K.H.); (R.P.); (F.C.M.)
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Davidson B, Gonzales E, Mast G, Laporta J. Late-gestation heat stress in Holstein dams programs in utero development of daughter's germline, triggering skin and hair morphology adaptations of granddaughters. JDS COMMUNICATIONS 2024; 5:83-88. [PMID: 38223391 PMCID: PMC10785235 DOI: 10.3168/jdsc.2023-0400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Accepted: 06/09/2023] [Indexed: 01/16/2024]
Abstract
Homeostasis and thermoregulation are influenced by the interplay of hair coat and skin characteristics. Our previous work indicated that hair and skin adaptations, triggered by in utero heat stress, affect thermoregulation in postnatal life. Herein, we investigate multigenerational carry-over effects of late-gestation heat stress on hair and skin characteristics beyond the first generation. Pregnant Holstein dams (F0, grand-dams) were heat stressed (HT, shade, n = 41) or provided active cooling (CL, shade, fans, and water soakers, n = 41) for the last 56 d of gestation during summer (temperature-humidity index ≥68). The first generation of heifers (F1, daughters) who were in utero heat stressed (HTF1, n = 36) or not (CLF1, n = 37) were born and raised as a cohort from birth to first calving. Thirty second-generation heifers (F2, granddaughters), born to HTF1 (HTF2, n = 12) and CLF1 (CLF2, n = 18), were raised as a cohort from birth to 70 d of age. Hair samples and skin biopsies from HTF2 and CLF2 were collected on postnatal d 70 (n = 6/group). Hair samples were subdivided into topcoat and undercoat, and skin tissue was fixed for ~18 h in 10% formalin, dehydrated, paraffin-embedded, sectioned, and stained with hematoxylin and eosin to visualize morphology. Variables analyzed included hair length and diameter; stratum corneum cross-sectional area and thickness; epidermis thickness; sweat gland depth, number, cross-sectional area, and average size; and sebaceous gland number, cross-sectional area, and average size. Measurements were performed using the ImageJ software and analyzed using PROC MIXED in SAS (SAS Institute Inc.). Hair length and diameter tended to be shorter and thicker in HTF2, compared with CLF2. The HTF2 skin had smaller stratum corneum cross-sectional area and tended to a thinner epidermis. to CLF2, HTF2 skin had more but smaller sebaceous glands, whereas no differences in sweat glands were observed. In summary, we report phenotypic alterations in hair and skin characteristics of granddaughters. Whether these adaptations grant improved postnatal thermoregulatory ability for the granddaughters remains to be investigated.
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Affiliation(s)
- B.D. Davidson
- Department of Animal and Dairy Sciences, University of Wisconsin–Madison, Madison, WI 53706
| | - E.T. Gonzales
- Department of Animal and Dairy Sciences, University of Wisconsin–Madison, Madison, WI 53706
| | - G.L. Mast
- Department of Animal and Dairy Sciences, University of Wisconsin–Madison, Madison, WI 53706
| | - J. Laporta
- Department of Animal and Dairy Sciences, University of Wisconsin–Madison, Madison, WI 53706
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Mateescu RG, Sarlo Davila KM, Hernandez AS, Andrade AN, Zayas GA, Rodriguez EE, Dikmen S, Oltenacu PA. Impact of Brahman genetics on skin histology characteristics with implications for heat tolerance in cattle. Front Genet 2023; 14:1107468. [PMID: 37229201 PMCID: PMC10203561 DOI: 10.3389/fgene.2023.1107468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 04/18/2023] [Indexed: 05/27/2023] Open
Abstract
Cattle lose heat predominantly through cutaneous evaporation at the skin-hair coat interface when experiencing heat stress. Sweating ability, sweat gland properties, and hair coat properties are a few of the many variables determining the efficacy of evaporative cooling. Sweating is a significant heat dissipation mechanism responsible for 85% of body heat loss when temperatures rise above 86⁰F. The purpose of this study was to characterize skin morphological parameters in Angus, Brahman, and their crossbred cattle. Skin samples were taken during the summer of 2017 and 2018 from a total of 319 heifers from six breed groups ranging from 100% Angus to 100% Brahman. Epidermis thickness decreased as the percentage of Brahman genetics increased where the 100% Angus group had a significantly thicker epidermis compared to the 100% Brahman animals. A more extended epidermis layer was identified in Brahman animals due to more pronounced undulations in this skin layer. Breed groups with 75% and 100% Brahman genes were similar and had the largest sweat gland area, indicative of superior resilience to heat stress, compared to breed groups with 50% or lower Brahman genetics. There was a significant linear breed group effect on sweat gland area indicating an increase of 862.0 µm2 for every 25% increase in Brahman genetics. Sweat gland length increased as the Brahman percentage increased, while the sweat gland depth showed an opposite trend, decreasing from 100% Angus to 100% Brahman. The number of sebaceous glands was highest in 100% Brahman animals which had about 1.77 more sebaceous glands (p < 0.05) per 4.6 mm2area. Conversely, the sebaceous gland area was greatest in the 100% Angus group. This study identified significant differences in skin properties related to heat exchange ability between Brahman and Angus cattle. Equally important, these differences are also accompanied by significant levels of variation within each breed, which is indicative that selection for these skin traits would improve the heat exchange ability in beef cattle. Further, selecting beef cattle for these skin traits would lead to increased resilience to heat stress without disrupting production traits.
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Affiliation(s)
- Raluca G. Mateescu
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Kaitlyn M. Sarlo Davila
- Infectious Bacterial Diseases Research Unit, National Animal Disease Centers, United States Department of Agriculture, Ames, IA, United States
| | - Aakilah S. Hernandez
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Andrea Nunez Andrade
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Gabriel A. Zayas
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Eduardo E. Rodriguez
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
| | - Serdal Dikmen
- Department of Animal Science, Faculty of Veterinary Medicine, Bursa Uludağ University, Bursa, Türkiye
| | - Pascal A. Oltenacu
- Department of Animal Sciences, University of Florida, Gainesville, FL, United States
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Davidson BD, Sarlo Davila KM, Mateescu RG, Dahl GE, Laporta J. Effect of in utero exposure to hyperthermia on postnatal hair length, skin morphology, and thermoregulatory responses. J Dairy Sci 2022; 105:8898-8910. [PMID: 36085111 DOI: 10.3168/jds.2022-22202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 06/05/2022] [Indexed: 11/19/2022]
Abstract
Skin and hair coat play important functions in maintaining homeostasis and thermoregulation for cattle, which can affect all modes of heat loss. Our objective was to investigate the effect of hyperthermia experienced in utero during late gestation on postnatal hair length, skin properties, and thermoregulation. Pregnant dams were heat stressed (n = 41) or actively cooled (n = 41) for the last ∼56 d of gestation and gave birth to heifers that were in utero heat stressed (IUHT) or in utero cooled (IUCL), respectively. Hair samples and skin tissue biopsies were collected from neck and rump locations at birth (d 0), 1 wk after weaning (d 63), and at 12 mo. Hair samples were also obtained at 4 and 8 mo. Skin tissue was stained with hematoxylin and eosin to visualize morphology. Hair length (short and long hairs, undercoat and topcoat, respectively), stratum corneum (SC) area, SC thickness, epidermis thickness, sweat gland (SWT) number, SWT cross-sectional area, SWT average size, sebaceous gland (SEB) number, SEB cross-sectional area, SEB average size, and sweat gland depth were assessed. Respiration rate, skin temperature, sweating rate, and rectal temperature was measured weekly from d 7 to 63. Additionally, thermoregulatory patterns were measured every 4 h over a 36-h interval beginning 4 d after weaning. Data were analyzed using PROC MIXED in SAS with a main effect of in utero treatment with location and time points analyzed separately. No difference in hair parameters were detected at d 0 or 12 mo. At d 63, IUHT heifers had longer average hair length (14.8 vs. 13.8 ± 0.2 mm, standard error), shorter undercoats (9.3 vs. 10.4 ± 0.3 mm), longer topcoats (19.6 vs. 17.1 ± 0.3 mm), and a greater difference between topcoat and undercoat (10.1 vs. 7.0 ± 0.4 mm). At 4 mo, IUHT heifers had longer average hair lengths (26.1 vs. 22.2 ± 1.0 mm) and longer topcoats (36.9 vs. 33.9 ± 1.1 mm), and at 8 mo, IUHT had longer average hair lengths (17.9 vs. 16.2 ± 0.6 mm), relative to IUCL. At d 0, IUHT heifers had more (13 vs. 9 ± 2 glands) but smaller average sized SEB (neck: 1,636 vs. 2,238 ± 243 µm2; rump: 2,100 vs. 3,352 ± 379 µm2) and reduced SC area (79,243 vs. 169,419 ± 13,071 µm2). At d 63, IUHT had fewer SEB (11 vs. 15 ± 2 glands), smaller SWT (0.16 vs. 0.23 ± 0.02 mm2), fewer SWT (16 vs. 23 ± 4 glands), and deeper SWT (0.5 vs. 0.4 ± 0.03 mm). At 12 mo, IUHT had greater distance from the skin surface to the most superficial SWT (0.016 vs. 0.015 ± 0.0004 mm), shorter distance to the deepest SWT (0.031 vs. 0.033 ± 0.001 mm), and smaller SWT (81.1 vs. 108.9 ± 10.8 µm2), relative to IUCL. When measured both weekly and hourly, IUHT heifers had higher rectal temperature and sweating rate. Overall, in utero hyperthermia triggers long-lasting hair and skin adaptations, possibly leading to differences in postnatal thermoregulation.
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Affiliation(s)
- B D Davidson
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, 53706
| | - K M Sarlo Davila
- Department of Animal Sciences, University of Florida, Gainesville 32608
| | - R G Mateescu
- Department of Animal Sciences, University of Florida, Gainesville 32608
| | - G E Dahl
- Department of Animal Sciences, University of Florida, Gainesville 32608
| | - J Laporta
- Department of Animal and Dairy Sciences, University of Wisconsin-Madison, 53706.
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Geisenberger D, Große Perdekamp M, Pollak S, Thierauf-Emberger A, Thoma V. Differing sizes of bullet entrance holes in skin of the anterior and posterior trunk. Int J Legal Med 2022; 136:1597-1603. [PMID: 36006518 PMCID: PMC9576652 DOI: 10.1007/s00414-022-02879-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 08/12/2022] [Indexed: 11/25/2022]
Abstract
The aim of the present study was to establish whether the size (diameter and area) of bullet entrance holes in skin varies between distant shots to the anterior and posterior trunk, respectively, when using the same ammunition (in concreto pistol cartridges 9 mm Luger). For that purpose, specimens of porcine skin from the belly region and the back were taken (10 samples each) and shot at from a distance of 1.6 m. The entrance holes were photo-documented under standardised conditions. After image processing for contrast enhancement, the maximum diameter and the area of each skin defect were measured automatically by means of an image analysis system. Both size parameters differed significantly depending on the body region affected. On the back with its comparatively thick dermis, the skin defects were considerably smaller than those on the ventral trunk where the corium is less thick. This difference can be explained by the fact that the elastic properties of skin are strongly determined by the connective tissue which is especially rich in fibres. The study results were consistent with the authors’ casework experience and support the assumption that the entrance site of gunshot wounds has a major influence on the size of the bullet hole in skin.
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Affiliation(s)
- D Geisenberger
- Institute of Forensic Medicine, Faculty of Medicine, University of Freiburg, Albertstraße 9, 79104, Freiburg, Germany
| | - M Große Perdekamp
- Institute of Forensic Medicine, Faculty of Medicine, University of Freiburg, Albertstraße 9, 79104, Freiburg, Germany
| | - S Pollak
- Institute of Forensic Medicine, Faculty of Medicine, University of Freiburg, Albertstraße 9, 79104, Freiburg, Germany
| | - A Thierauf-Emberger
- Institute of Forensic Medicine, Faculty of Medicine, University of Freiburg, Albertstraße 9, 79104, Freiburg, Germany
| | - V Thoma
- Institute of Forensic Medicine, Faculty of Medicine, University of Freiburg, Albertstraße 9, 79104, Freiburg, Germany.
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Sorushanova A, Skoufos I, Tzora A, Mullen AM, Zeugolis DI. The influence of animal species, gender and tissue on the structural, biophysical, biochemical and biological properties of collagen sponges. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2021; 32:12. [PMID: 33475864 PMCID: PMC7819930 DOI: 10.1007/s10856-020-06485-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 12/18/2020] [Indexed: 05/03/2023]
Abstract
Although collagen type I is extensively used in biomedicine, no study to-date has assessed how the properties of the produced scaffolds are affected as a function of species, gender and tissue from which the collagen was extracted. Herein, we extracted and characterised collagen from porcine and bovine, male and female and skin and tendon tissues and we subsequently fabricated and assessed the structural, biophysical, biochemical and biological properties of collagen sponges. All collagen preparations were of similar purity and free-amine content (p > 0.05). In general, the porcine groups yielded more collagen; had higher (p < 0.05) denaturation temperature and resistance to enzymatic degradation; and lower (p < 0.05) swelling ratio and compression stress and modulus than the bovine groups of the same gender and tissue. All collagen preparations supported growth of human dermal fibroblasts and exhibited similar biological response to human THP-1 monocytes. These results further illustrate the need for standardisation of collagen preparations for the development of reproducible collagen-based devices. Assessment of the physicochemical and biological properties of collagen sponges as a function of animal species (bovine versus porcine), gender (male versus female) and tissue (skin versus tendon).
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Affiliation(s)
- Anna Sorushanova
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biomedical Sciences Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
- Science Foundation Ireland (SFI) Centre for Research in Medical Devices (CÚRAM), Biomedical Sciences Building, National University of Ireland Galway (NUI Galway), Galway, Ireland
| | - Ioannis Skoufos
- Laboratory of Animal Science, Nutrition and Biotechnology, School of Agriculture, University of Ioannina, Arta, Greece
| | - Athina Tzora
- Laboratory of Animal Science, Nutrition and Biotechnology, School of Agriculture, University of Ioannina, Arta, Greece
| | | | - Dimitrios I Zeugolis
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Biomedical Sciences Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.
- Science Foundation Ireland (SFI) Centre for Research in Medical Devices (CÚRAM), Biomedical Sciences Building, National University of Ireland Galway (NUI Galway), Galway, Ireland.
- Regenerative, Modular & Developmental Engineering Laboratory (REMODEL), Faculty of Biomedical Sciences, Università della Svizzera Italiana (USI), Lugano, Switzerland.
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Gunawardana M, Remedios-Chan M, Sanchez D, Webster S, Galvan P, Fanter R, Castonguay AE, Webster P, Moss JA, Kuo J, Gallay PA, Vincent KL, Motamedi M, Weinberger D, Marzinke MA, Hendrix CW, Baum MM. Multispecies Evaluation of a Long-Acting Tenofovir Alafenamide Subdermal Implant for HIV Prophylaxis. Front Pharmacol 2020; 11:569373. [PMID: 33536904 PMCID: PMC7849190 DOI: 10.3389/fphar.2020.569373] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 10/19/2020] [Indexed: 12/17/2022] Open
Abstract
New HIV-1 infection rates far outpace the targets set by global health organizations, despite important progress in curbing the progression of the epidemic. Long-acting (LA) formulations delivering antiretroviral (ARV) agents for HIV-1 pre-exposure prophylaxis (PrEP) hold significant promise, potentially facilitating adherence due to reduced dosing frequency compared to oral regimens. We have developed a subdermal implant delivering the potent ARV drug tenofovir alafenamide that could provide protection from HIV-1 infection for 6 months, or longer. Implants from the same lot were investigated in mice and sheep for local safety and pharmacokinetics (PKs). Ours is the first report using these animal models to evaluate subdermal implants for HIV-1 PrEP. The devices appeared safe, and the plasma PKs as well as the drug and metabolite concentrations in dermal tissue adjacent to the implants were studied and contrasted in two models spanning the extremes of the body weight spectrum. Drug and drug metabolite concentrations in dermal tissue are key in assessing local exposure and any toxicity related to the active agent. Based on our analysis, both animal models were shown to hold significant promise in LA product development.
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Affiliation(s)
- Manjula Gunawardana
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Mariana Remedios-Chan
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Debbie Sanchez
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Simon Webster
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Patricia Galvan
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Rob Fanter
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Amalia E. Castonguay
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Paul Webster
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - John A. Moss
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
| | - Joseph Kuo
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
| | - Philippe A. Gallay
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States
| | - Kathleen L. Vincent
- Center for Biomedical Engineering, University of Texas Medical Branch at Galveston, Galveston, TX, United States
| | - Massoud Motamedi
- Center for Biomedical Engineering, University of Texas Medical Branch at Galveston, Galveston, TX, United States
| | | | - Mark A. Marzinke
- Department of Medicine, Johns Hopkins University, Baltimore, MD, United States
- Department of Pathology, Johns Hopkins University, Baltimore, MD, United States
| | - Craig W. Hendrix
- Department of Medicine, Johns Hopkins University, Baltimore, MD, United States
| | - Marc M. Baum
- Department of Chemistry, Oak Crest Institute of Science, Monrovia, CA, United States
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