Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0038362 (
stomatitis
)
8,852
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Lentiviral vectors are increasingly used in clinical trials to treat genetic diseases. Our research has focused on strategies to improve lentiviral gene transfer efficiency in the airways. Previously we demonstrated that a feline immunodeficiency virus (FIV)-based lentiviral vector pseudotyped with the baculovirus envelope glycoprotein GP64 (GP64-FIV) efficiently transduced mouse nasal epithelia in vivo but transduced mouse intrapulmonary airways with 10-fold less efficiency. Here, we demonstrate that members of a family of proteins with antiviral activity, interferon-induced transmembrane proteins (IFITMs), are more highly expressed in mouse intrapulmonary airways as compared with mouse nasal airways. Using GP64- and VSV-G (vesicular
stomatitis
virus G glycoprotein)-pseudotyped FIV, we show that expression of mouse IFITM1,
IFITM2
, and IFITM3 restricts gene transfer. Further, we show that both the nasal and intrapulmonary airways of IFITM locus knockout mice are more efficiently transduced with GP64-FIV than their heterozygous littermates. In anticipation of transitioning our studies into pig models of airway disease and clinical trials in humans, we investigated the ability of pig and human IFITMs to restrict lentiviral gene transfer. We observed that both human and pig IFITMs partially restricted both VSV-G-FIV and GP64-FIV transduction in vitro. Previous studies have focused on IFITM-mediated restriction of replication-competent wild-type viruses; however, these results implicate the IFITM proteins as restriction factors that can limit lentivirus-based vector gene transfer to airway epithelia. The findings are relevant to future preclinical and clinical airway gene therapy trials using lentivirus-based vectors.
...
PMID:Human, Pig, and Mouse Interferon-Induced Transmembrane Proteins Partially Restrict Pseudotyped Lentiviral Vectors. 2700 32
Interferon-induced transmembrane (IFITM) proteins are encoded by many vertebrate species and exhibit antiviral activities against a wide range of viruses. IFITM3, when present in virus-producing cells, reduces the fusion potential of HIV-1 virions, but the mechanism is poorly understood. To define the breadth and mechanistic basis for the antiviral activity of IFITM3, we took advantage of a murine leukemia virus (MLV)-based pseudotyping system. By carefully controlling amounts of IFITM3 and envelope protein (Env) in virus-producing cells, we found that IFITM3 potently inhibits MLV infectivity when Env levels are limiting. Loss of infectivity was associated with defective proteolytic processing of Env and lysosomal degradation of the Env precursor. Ecotropic and xenotropic variants of MLV Env, as well as HIV-1 Env and vesicular
stomatitis
virus glycoprotein (VSV-G), are sensitive to IFITM3, whereas Ebola glycoprotein is resistant, suggesting that IFITM3 selectively inactivates certain viral glycoproteins. Furthermore, endogenous IFITM3 in human and murine cells negatively regulates MLV Env abundance. However, we found that the negative impact of IFITM3 on virion infectivity is greater than its impact on decreasing Env incorporation, suggesting that IFITM3 may impair Env function, as well as reduce the amount of Env in virions. Finally, we demonstrate that loss of virion infectivity mediated by IFITM3 is reversed by the expression of glycoGag, a murine retrovirus accessory protein previously shown to antagonize the antiviral activity of SERINC proteins. Overall, we show that IFITM3 impairs virion infectivity by regulating Env quantity and function but that enhanced Env expression and glycoGag confer viral resistance to IFITM3.
IMPORTANCE
The viral envelope glycoprotein, known as "Env" in
Retroviridae
, is found on the virion surface and facilitates virus entry into cells by mediating cell attachment and fusion. Env is a major structural component of retroviruses and is targeted by all arms of the immune response, including adaptive and innate immunity. Less is known about how cell-intrinsic immunity prevents retrovirus replication at the level of individual cells. Here, we show that cellular IFITM3 and
IFITM2
inhibit the fusion potential of retroviral virions by inhibiting Env protein via a two-pronged mechanism. IFITM proteins inhibit Env abundance in cells and also impair its function when levels are low. The posttranslational block of retroviral Env function by IFITM proteins is likely to impede both exogenous and endogenous retrovirus replication. In support of a relevant role for IFITM3 in retrovirus control, the retroviral accessory protein glycoGag counteracts IFITM3 function to promote virus infectivity.
...
PMID:IFITM3 Reduces Retroviral Envelope Abundance and Function and Is Counteracted by glycoGag. 3196 38