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1.
Analyst ; 149(13): 3636-3650, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38814097

RESUMO

This work presents a thorough characterization of Helaina recombinant human lactoferrin (rhLF, Effera™) expressed in a yeast system at an industrial scale for the first time. Proteomic analysis confirmed that its amino acid sequence is identical to that of native human LF. N-linked glycans were detected at three known glycosylation sites, namely, Asparagines-156, -497, and -642 and they were predominantly oligomannose structures having five to nine mannoses. Helaina rhLF's protein secondary structure was nearly identical to that of human milk lactoferrin (hmLF), as revealed by microfluidic modulation spectroscopy. Results of small-angle X-ray scattering (SAXS) and analytical ultracentrifugation analyses confirmed that, like hmLF, Helaina rhLF displayed well-folded globular structures in solution. Reconstructed solvent envelopes of Helaina rhLF, obtained through the SAXS analysis, demonstrated a remarkable fit with the reported crystalline structure of iron-bound native hmLF. Differential scanning calorimetry investigations into the thermal stability of Helaina rhLF revealed two distinct denaturation temperatures at 68.7 ± 0.9 °C and 91.9 ± 0.5 °C, consistently mirroring denaturation temperatures observed for apo- and holo-hmLF. Overall, Helaina rhLF differed from hmLF in the N-glycans they possessed; nevertheless, the characterization results affirmed that Helaina rhLF was of high purity and exhibited globular structures closely akin to that of hmLF.


Assuntos
Lactoferrina , Proteínas Recombinantes , Saccharomycetales , Lactoferrina/química , Lactoferrina/metabolismo , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/biossíntese , Saccharomycetales/química , Saccharomycetales/metabolismo , Saccharomycetales/genética , Espalhamento a Baixo Ângulo , Sequência de Aminoácidos , Glicosilação , Difração de Raios X
2.
Int J Toxicol ; 43(4): 407-420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38647416

RESUMO

The oral toxicity of recombinant human lactoferrin (rhLF, Helaina rhLF, Effera™) produced in Komagataella phaffii was investigated in adult Sprague Dawley rats by once daily oral gavage for 14 consecutive days. The study used groups of 3-6 rats/sex/dose. The vehicle control group received sodium citrate buffer, and the test groups received daily doses of 200, 1000, and 2000 mg of rhLF in sodium citrate buffer per kg body weight. Bovine LF at 2000 mg/kg body weight per day was used as a comparative control. Clinical observations, body weight, hematology, clinical chemistry, iron parameters, immunophenotyping, and gross examination at necropsy were used as criteria for detecting the effects of treatment in all groups and to help select dose levels for future toxicology studies. Quantitative LF levels were also analyzed as an indication of bioavailability. Overall, administration of Helaina rhLF by once daily oral gavage for 14 days was well tolerated in rats at levels up to 2000 mg/kg/day, or 57 × Helaina's intended commercial use in adults, and indicating that a high dose of 2000 mg/kg/day is appropriate for future definitive toxicology studies.


Assuntos
Relação Dose-Resposta a Droga , Lactoferrina , Ratos Sprague-Dawley , Proteínas Recombinantes , Animais , Lactoferrina/toxicidade , Proteínas Recombinantes/toxicidade , Masculino , Feminino , Humanos , Ratos , Nível de Efeito Adverso não Observado , Administração Oral , Peso Corporal/efeitos dos fármacos , Saccharomycetales
3.
Food Chem Toxicol ; 189: 114727, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38735359

RESUMO

Published studies on the glycosylation, absorption, distribution, metabolism, excretion, and safety outcomes of orally ingested recombinant human lactoferrin (rhLF) were reviewed in the context of unanswered safety questions, including alloimmunization, allergenicity, and immunotoxicity potential of rhLF during repeated exposure. The primary objective was to summarize current safety data of rhLF produced in transgenic host expression systems. Overall, results from animal and human studies showed that rhLF was well tolerated and safe. Animal data showed no significant toxicity-related outcomes among any safety or tolerability endpoints. The no observed adverse effect levels (NOAEL) were at the highest level tested in both iron-desaturated and -saturated forms of rhLF. Although one study reported outcomes of rhLF on immune parameters, no animal studies directly assessed immunogenicity or immunotoxicity from a safety perspective. Data from human studies were primarily reported as adverse events (AE). They showed no or fewer rhLF-related AE compared to control and no evidence of toxicity, dose-limiting toxicities, or changes in iron status in various subpopulations. However, no human studies evaluated the immunomodulatory potential of rhLF as a measure of safety. Following this review, a roadmap outlining preclinical and clinical studies with relevant safety endpoints was developed to address the unanswered safety questions.


Assuntos
Lactoferrina , Proteínas Recombinantes , Lactoferrina/toxicidade , Humanos , Animais , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/toxicidade , Inocuidade dos Alimentos , Nível de Efeito Adverso não Observado
4.
Front Immunol ; 15: 1380028, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114650

RESUMO

Introduction: Prior to the introduction of novel food ingredients into the food supply, safety risk assessments are required, and numerous prediction models have been developed and validated to evaluate safety. Methods: The allergenic risk potential of Helaina recombinant human lactoferrin (rhLF, Effera™), produced in Komagataella phaffii (K. phaffii) was assessed by literature search, bioinformatics sequence comparisons to known allergens, glycan allergenicity assessment, and a simulated pepsin digestion model. Results: The literature search identified no allergenic risk for Helaina rhLF, K. phaffii, or its glycans. Bioinformatics search strategies showed no significant risk for cross-reactivity or allergenicity between rhLF or the 36 residual host proteins and known human allergens. Helaina rhLF was also rapidly digested in simulated gastric fluid and its digestibility profile was comparable to human milk lactoferrin (hmLF), further demonstrating a low allergenic risk and similarity to the hmLF protein. Conclusion: Collectively, these results demonstrate a low allergenic risk potential of Helaina rhLF and do not indicate the need for further clinical testing or serum IgE binding to evaluate Helaina rhLF for risk of food allergy prior to introduction into the food supply.


Assuntos
Alérgenos , Hipersensibilidade Alimentar , Lactoferrina , Lactoferrina/imunologia , Humanos , Hipersensibilidade Alimentar/imunologia , Alérgenos/imunologia , Proteínas Recombinantes/imunologia , Saccharomycetales/imunologia , Saccharomycetales/metabolismo , Medição de Risco , Biologia Computacional/métodos
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