Research Models

5xFAD (C57BL6)

Synonyms: 5XFAD, APP/PS1, Tg6799, Tg-5xFAD

Species: Mouse
Genes: APP, PSEN1
Mutations: APP KM670/671NL (Swedish), APP I716V (Florida), APP V717I (London), PSEN1 M146L (A>C), PSEN1 L286V
Modification: APP: Transgenic; PSEN1: Transgenic
Disease Relevance: Alzheimer's Disease
Strain Name: B6.Cg-Tg(APPSwFlLon,PSEN1*M146L*L286V)6799Vas/Mmjax
Genetic Background: C57BL6
Availability: Available from The Jackson Laboratory, JAX MMRRC Stock# 034848

Summary

5xFAD mice express human APP and PSEN1 transgenes with a total of five AD-linked mutations: the Swedish (K670N/M671L), Florida (I716V), and London (V717I) mutations in APP, and the M146L and L286V mutations in PSEN1. 5xFAD mice were originally created on a hybrid B6SJL background (mice on this background are described elsewhere). However, many laboratories preferred to use mice on a C57BL6 background, and have since generated their own congenic lines through backcrossing. 5xFAD mice on a C57BL/6J background are commercially available through Jackson Labs.

The descriptions on this page refer to mice hemizygous for the APP and PSEN1 transgenes. Compared with hemizygous 5xFAD mice, animals homozygous for the transgenes exhibit more severe amyloid pathology; behavioral deficits are also more severe and/or have an earlier age of onset (Richard et al., 2015).

Neuropathology

Amyloid pathology appears earliest and is most severe in the subiculum and cortical layer V. Human APP was detected by immunohistochemistry in subicular and layer V pyramidal neurons in animals as young as 16 days, and intraneuronal Aβ was seen in these neurons at 6 weeks (Richard et al., 2015). Extracellular amyloid plaques were detected by immunohistochemistry in hippocampus, cortex, and thalamus of 2-month animals (Richard et al., 2015). Intraneuronal Aβ and extracellular plaques were also observed in spinal cord by 3 months, the youngest age examined (Jawhar et al., 2012). Thioflavin-S-positive plaques emerge between 2 and 4 months in frontal, parietal, entorhinal cortices and dentate gyrus (Giannoni et al., 2016). Plaques in 5xFAD mice were found to contain N-terminally-truncated Aβ (Guzmán et al., 2014; Savastano et al., 2015; Wirths et al., 2017).

Dystrophic neurites (Jawhar et al., 2012), microgliosis, and astrogliosis (Giannoni et al., 2016) are associated with amyloid plaques in this model.

Mice exhibit progressive cerebral amyloid angiopathy (CAA) in superficial, leptomeningeal vessels, beginning at approximately 3 months of age (Giannoni et al., 2016). Microcapillary leakage was seen to increase with age in both 5xFAD and wild-type brains, but was more severe in the transgenic animals. Although microvascular damage was common, and associated with microgliosis, amyloid deposits around microvessels were rare.

Loss of specific synapses has been observed in 5xFAD mice crossed with mice that express Yellow Fluorescent Protein (YFP). Spine density was reduced in pyramidal neurons in somatosensory and prefrontal cortices, but not in the hippocampi, of 6-month 5xFAD-YFP mice, compared with mice expressing YFP alone (Crowe and Ellis-Davies, 2013).

An approximately 40 percent loss of layer V pyramidal neurons was seen in year-old 5xFAD mice, although neuron numbers in (frontal) cortex overall and in hippocampal CA1 do not differ from wild-type mice (Jawhar et al., 2012).

Myelin abnormalities are present in mice as young as one month and become more severe with age. At one month, decreased levels of myelin basic protein (Wu et al., 2018) and thinner myelin sheaths (Gu et al., 2018) are seen in multiple brain regions of 5xFAD mice compared with wild-type mice. Myelin becomes thinner with age, and morphologically abnormal myelin (split myelin, axons with two myelin sheaths, myelin outfolding, ballooned myelin) appears earlier and more frequently in transgenic mice (Gu et al., 2018). Axons are also affected in this model: axon calibers are decreased in CA1 and retrosplenial cortex at 2 to 3 months of age (Gu et al., 2018), and axonal swellings, indicative of degenerating axons, were observed in multiple brain regions of mice as young as 3 months, independent of plaques (Jawhar et al., 2012; Richard et al., 2015).

Electrophysiology

Electrophysiological evidence of synaptic deficits was obtained from 8- to 12-week mice (Buskila et al., 2013). The frequencies and amplitudes of miniature excitatory postsynaptic currents were decreased in layer V neurons, reflecting pre- and post-synaptic dysfunction, respectively. Layer V neurons also displayed aberrant synaptic plasticity: While spike-timing-dependent long-term potentiation was induced in layer V neurons from wild-type mice, the same stimulation protocol induced long-term depression in neurons from 5xFAD mice. Layer V neurons in 5xFAD mice are also less excitable than neurons in wild-type mice, although the properties of neurons in layers II/III did not differ between genotypes.

Behavior

Impairments of spatial working memory, assessed in a cross-maze test, emerge between 3 and 6 months and worsen with age (Jawhar et al., 2012). (The cross-maze test is similar to, but possibly more sensitive than, the Y maze, as the test apparatus consists of four arms instead of three. As for the Y maze, spontaneous alternation in the cross maze is used to evaluate working memory.) Exploratory behavior—total number of arm entries—is similar in 5xFAD and wild-type mice at least until a year of age.

Progressive decreases in anxiety, as measured in the elevated plus-maze, also emerge between 3 and 6 months. Reduced anxiety in 5xFAD mice is also seen in the open field, but differences between transgenic and wild-type mice are not seen until 9 to 12 months in this test. Locomotor activity in the open field is normal until at least 12 months (Jawhar et al., 2012).

One group reported normal spatial memory function in the Morris water maze at least until 7 months (Richard et al., 2015), while a second group reported memory deficits in the water maze in mice as young as one month (Gu et al., 2018; Wu et al., 2018). This discrepancy may be traced to differences in the way memory impairment was defined. The first group concluded that memory function was normal since transgenic mice exhibited a clear preference for the target quadrant in a probe test (i.e., mice spent more than 25 percent of the test in the quadrant of the pool where the escape platform had been located during training trials). The second group compared target-quadrant occupancy between 5xFAD and wild-type mice, and found that the transgenic mice spent somewhat less time in the target quadrant, although both genotypes appear to have a preference for this quadrant. Additionally, using a second measure—number of platform crossings—5xFAD mice showed a small, but statistically significant, difference from wild-type.

Sensorimotor deficits in balance-beam and string-suspension tests have been observed in 9-month mice (Jawhar et al., 2012).

Abnormal reflexes, specifically hind and forelimb clasping in a tail-suspension test, are seen as early as 5 months (Richard et al., 2015).

Omics

Between 2 and 4 months of age, there is a surge in the number of genes differentially expressed in the hippocampi of 5xFAD and wild-type mice—from 42 transcripts at 2 months to more than 1,300 at 4 months (Bundy et al., 2018). Gene Ontology analysis of the genes upregulated in 4-month 5xFAD showed an enrichment for terms associated with immune activation. More genes were found to be differentially expressed in females (766) than males (537). Among 4-month 5xFAD, slightly increased levels of human APP and PSEN1 mRNAs were found in females relative to males.

Other

Manganese-enhanced magnetic resonance imaging (MEMRI) has been used to map regional activity in the brains of 5xFAD mice (Tang et al., 2016; Nie et al., 2019). Age-dependent, region-specific differences were seen between transgenic and wild-type mice, with activity in the hippocampus and amygdala consistently elevated in transgenic mice between 1 and 5 months of age (the oldest age studied).

Reduced body weight of 5xFAD, compared with wild-type mice, has been reported (Jawhar et al., 2012; Richard et al., 2015).

Modification Details

These transgenic mice were made by co-injecting two vectors encoding APP (with Swedish [K670N/M671L], Florida [I716V], and London [V717I] mutations) and PSEN1 (with M146L and L286V mutations), each driven by the mouse Thy1 promoter. The transgenes inserted at a single locus, Chr3:6297836 (Build GRCm38/mm10), where they do not affect any known genes (Goodwin et al., 2019). Mice on the original hybrid B6SJL background were backcrossed to C57BL6 mice for at least five generations.

Related Strains

5xFAD (B6SJL). This is the original 5xFAD line, on a hybrid B6SJL background.

AD-BXDs. This panel of strains was created to investigate the influence of genetic background on amyloid-related phenotypes (Neuner et al., 2019). 5xFAD mice on an inbred C57BL/6J background were bred to the BXD reference panel, a series of recombinant inbred strains derived from C57BL/6 and DBA/2J (Taylor et al., 1999). Individual AD-BXD strains are available as F1 hybrids from The Jackson Laboratory. For more information about these mice, see the Alzforum News story.

Phenotype Characterization

When visualized, these models will distributed over a 18 month timeline demarcated at the following intervals: 1mo, 3mo, 6mo, 9mo, 12mo, 15mo, 18mo+.

Absent

No Data

  • Tangles

Plaques

Amyloid plaques observed in hippocampus, cortex, thalamus, and spinal cord.

Tangles

No data.

Neuronal Loss

Approximate 40 percent loss of layer V pyramidal neurons at one year.

Gliosis

Microgliosis and astrogliosis are associated with amyloid plaques; microgliosis is associated with vascular damage.

Synaptic Loss

Spine density was reduced in pyramidal neurons in somatosensory and prefrontal cortices, but not in the hippocampi, of 5xFAD mice crossed with mice expressing yellow fluorescent protein (YFP mice), compared with mice expressing YFP alone.

Changes in LTP/LTD

While spike-timing-dependent long-term potentiation was induced in layer V neurons from wild-type mice, the same stimulation protocol induced long-term depression in neurons from 5xFAD mice.

Cognitive Impairment

Impairments of spatial working memory and reduced anxiety emerge between 3 and 6 months and worsen with age.

Last Updated: 09 Apr 2019

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References

Research Models Citations

  1. AD-BXD

News Citations

  1. Missing Ingredient: New Mice Model Alzheimer’s Genetic Variability

Paper Citations

  1. . Gene Dosage Dependent Aggravation of the Neurological Phenotype in the 5XFAD Mouse Model of Alzheimer's Disease. J Alzheimers Dis. 2015;45(4):1223-36. PubMed.
  2. . Motor deficits, neuron loss, and reduced anxiety coinciding with axonal degeneration and intraneuronal Aβ aggregation in the 5XFAD mouse model of Alzheimer's disease. Neurobiol Aging. 2012 Jan;33(1):196.e29-40. PubMed.
  3. . Cerebrovascular pathology during the progression of experimental Alzheimer's disease. Neurobiol Dis. 2016 Apr;88:107-17. Epub 2016 Jan 8 PubMed.
  4. . Abundance of Aβ₅-x like immunoreactivity in transgenic 5XFAD, APP/PS1KI and 3xTG mice, sporadic and familial Alzheimer's disease. Mol Neurodegener. 2014 Apr 2;9:13. PubMed.
  5. . N-truncated Aβ2-X starting with position two in sporadic Alzheimer's disease cases and two Alzheimer mouse models. J Alzheimers Dis. 2015;49(1):101-10. PubMed.
  6. . N-truncated Aβ4-x peptides in sporadic Alzheimer's disease cases and transgenic Alzheimer mouse models. Alzheimers Res Ther. 2017 Oct 4;9(1):80. PubMed.
  7. . Spine pruning in 5xFAD mice starts on basal dendrites of layer 5 pyramidal neurons. Brain Struct Funct. 2013 Feb 17; PubMed.
  8. . LINGO-1 antibody ameliorates myelin impairment and spatial memory deficits in the early stage of 5XFAD mice. CNS Neurosci Ther. 2018 May;24(5):381-393. Epub 2018 Feb 9 PubMed.
  9. . Myelin changes at the early stage of 5XFAD mice. Brain Res Bull. 2018 Mar;137:285-293. Epub 2017 Dec 28 PubMed.
  10. . Synaptic deficits in layer 5 neurons precede overt structural decay in 5xFAD mice. Neuroscience. 2013 Dec 19;254:152-9. PubMed.
  11. . Sex-biased hippocampal pathology in the 5XFAD mouse model of Alzheimer's disease: A multi-omic analysis. J Comp Neurol. 2018 Oct 5; PubMed.
  12. . Spatial learning and memory impairments are associated with increased neuronal activity in 5XFAD mouse as measured by manganese-enhanced magnetic resonance imaging. Oncotarget. 2016 Sep 6;7(36):57556-57570. PubMed.
  13. . A stereotaxic MRI template set of mouse brain with fine sub-anatomical delineations: Application to MEMRI studies of 5XFAD mice. Magn Reson Imaging. 2019 Apr;57:83-94. Epub 2018 Oct 22 PubMed.
  14. . Large-scale discovery of mouse transgenic integration sites reveals frequent structural variation and insertional mutagenesis. Genome Res. 2019 Mar;29(3):494-505. Epub 2019 Jan 18 PubMed.
  15. . Harnessing Genetic Complexity to Enhance Translatability of Alzheimer's Disease Mouse Models: A Path toward Precision Medicine. Neuron. 2019 Feb 6;101(3):399-411.e5. Epub 2018 Dec 27 PubMed.
  16. . Genotyping new BXD recombinant inbred mouse strains and comparison of BXD and consensus maps. Mamm Genome. 1999 Apr;10(4):335-48. PubMed.

Other Citations

  1. elsewhere

External Citations

  1. The Jackson Laboratory
  2. The Jackson Laboratory, JAX MMRRC Stock# 034848

Further Reading

No Available Further Reading