Percy & Barthold Flashcards
What two species contributed to M. m. molossinus?
M. m. musculus and M. m. castaneus
How does substrain divergence occur?
Spontaneous mutation, retrotransposon integrations, and residual heterozygosity.
Describe C57BL/6 mice.
Standard background strain.
Bred for longevity. Develop hydrocephalus, hippocampal neurodegeneration, microphthalmia and anophthalmia, age-related cochlear degeneration and hearing loss, and malocclusion. Barbering, alopecia, and staphylococcal ulcerative dermatitis.
Aged mice develop acidophilic macrophage pneumonia and epithelial hylalinosis, accelerated in moth-eaten. May develop late-onset amyloidosis.
Neoplasia: Lymphoma, hemangiosarcoma, pituitary adenoma
Describe BALB/c mice.
Males pugilistic.
Prone to dystrophic epicardial mineralization of the right ventricular free wall, myocardial degeneration, auricular thrombosis, corneal opacities, conjunctivitis, blepharitis, and periorbital abscesses. Hypocallosity, age-related hearing loss, hepatocellular fatty change.
Resistant to spontaneous
amyloidosis.
Neoplasia: Pulmonary adenomas, lymphomas, Harderian gland tumors, adrenal adenomas. Myoepitheliomas of salivary, preputial, and other exocrine glands.
Describe C3H/He mice.
Agouti that are blind due to rd1 mutation (pde6b^rd1).
Prone to corneal opacities, late-onset hearing loss, focal myocardial and skeletal mineralization, myocardial degeneration. Alopecia areata with age. Neoplasia: Susceptible to MMTV-induce mammary neoplasia later in life. Hepatocellular tumors.
Describe 129 mice.
Most frequent source of embryonic stem cells. Not a single strain, but recognized by 16 strains and substrains. Designation with P, S, T, or X.
Variation in coat color.
Prone to hypocallosity, pulmonary proteinosis, epithelial hyalinosis, megaesophagus.
129P3 - Blepharitis and conjunctivitis
Neoplasia: Lung, Harderian gland, ovarian, and hemangiosarcoma. 129/Sv - Testicular teratomas (embryonal carcinomas)
Describe FVB/N mice.
Inbred Swiss mice. Blind due to homozygosity of rd1 (Pde6b^rd1).
Prone to seizures, persistent mammary hyperplasia, hyperplasia of adenomas or prolactin-secreting cells in anterior pituitary.
Neoplasms: Mammary tumors rare. Tumors of lung, pituitary, Harderian gland, liver, lymphoma, and pheochromocytoma.
Describe NOD mice.
Inbred Swiss selectively bred for cataracts, found with type 1 diabetes.
Defects in macrophage and dendritic function, NK cells, regulatory T helper, and are complement 5a deficient.
Susceptibility to diabetes highest in germ-free environment.
Describe NSG mice.
NOD SCID Gamma.
NOD char (Defective in NK, macrophage, and dendritic cells), SCID (T and B cells), and Il-2 receptor gamma (Gamma)
Optimal host for xenogenic transplants
Describe Outbred Swiss mice.
Not wild type.
Many have retinal rd1 degeneration, prone to amyloidosis.
Neoplasia: Lymphoma, pulmonary adenomas, liver tumors, pituitary adenomas, and hemangiomas/sarcomas.
Why is hermaphroditism common in chimeric mice? How can this present?
Most ES cell lines are male (XY) but blastocysts are male or female. XX/XY chimeras usually phenotypically male, but may have testicular hypoplasia and lower fertility. May have cystic Muellerian duct remnants, an ovary and a testis, and/or ovotestes.
May see extragonadal teratomas arising from 129 cells in chimeric mice in perigenital regions and midline
Embryonic/fetal viability is most often influenced by abnormalities in which tissues?
Placenta, liver, and cardiovascular system.
How does hair grow in mice? Where is pigment found?
Grows cranially and progresses caudally. Melanin pigment restricted to hair follicle epithelium and hair shaft, not present in epidermis.
Describe mouse erythrocytes.
Small, high reticulocyte count, with moderate polychromasia and anisocytosis.
Describe mouse lymphocytes.
Predominant circulating leukocyte (75%).
Describe granulocytes in mice.
Peripheral blood granulocytes tend to be hypersegmented. Band cells rare, except with chronic suppurative infections. Mature male mice have higher granulocyte count than females. Granulocytes in tissues and bone marrow often have ring-shaped nuclei.
Describe the ring-shaped nuclei of granulocytes.
Can be visualized as early as in the progranulocyte stage in bone marrow, spleen, and liver. Rare in peripheral blood. Also occur in cells of monocytic lineage.
Describe murine basophils.
Rare
Describe the mouse platelet mass.
Large platelet mass due to high numbers and relatively low mean volume.
Describe hematopoiesis in the mouse.
Spleen is a major hematopoietic organ throughout life. Hematopoiesis found in liver up to weaning age but may return in adults during disease states - Can be misconstrued as inflammation. Hematopoiesis remains active in long bones throughout life
Viral attack of what tissues in neonatal mice can result in failure to suckle?
Vomeronasal organ and olfactory tissue
Respiratory epithelium containing eosinophilic secretory inclusions (hyalinosis) is especially obvious in what mice?
B6 and 129
Cartilage surrounds only the extrapulmonary airways in what species?
Mice, rats, and hamsters.
Cardiac muscle surrounds what vessels? What can this be mistaken for?
Major branches of pulmonary veins. Should not be mistaken for medial hypertrophy.
Bronchus-associated lymphoid tissue is normally present only at the hilus of the lung, except in what species?
Hamsters
What organized lymphoid structures are present in the pleura in mice?
Lymphoid accumulations on the visceral pleura, within interlobular clefts. Contiguous with the underlying lung tissue and similar to milkspots in the peritoneum.
What is alveolar histiocytosis?
Focal subpleural accumulation of alveolar macrophages. Common in mice and rats.
What percentage of a mouse’s dietary intake is feces?
Approx. 1/3
What sexual dimorphism is found in the salivary glands of mice?
Submandibular gland of males is nearly twice that of females. Parotid of males is also larger. Male submandibular glands have increased secretory granules in the cytoplasm of serous cells. These glands undergo similar masculinization in pregnant and lactating females.
Describe Paneth cells in mice.
Occupy the crypt bases of the S.I. Specialized enterocytes with prominent eosinophilic cytoplasmic granules that are larger in mice than other lab rodents.
Physiological mucosal hyperplasia is found in mice at what life stage?
Pregnant and lactating.
What are unique features of the neonatal mouse intestine?
S.I. enterocytes are vacuolated and may contain eosinophilic inclusions due to the presence of the apical-tubular system, which is involved in uptake of macromolecules.
Neonatal bowel has very shallow crypts of Leiberkuhn populated with mitotically inactive stem cells and very long villi that are populated with terminally differentiated, absorptive epithelium. Intestinal cell turnover is slow, making neonates vulnerable to acute cytolytic viruses. Turnover kinetics accelerate with acquisition of microflora and dietary stimuli.
What are common features of hepatocytes?
Polyploidy, cytomegaly, anisokaryosis, polykarya, and karyomegaly.
What normal process can give the appearance of nuclear inclusion bodies in the liver?
Cytoplasmic invagination into the nucleus.
Describe hematopoiesis in the mouse liver.
Normally occurs in infants, but wanes by weaning age. Can be found in hepatic sinusoids of older mice, particularly in disease states.
Are fat vacuoles a common finding in mice livers? Which strains are predisposed?
Hepatocytes frequently contain cytoplasmic fat vacuoles. BALB mice normally have diffuse hepatocellular fatty changes, resulting in grossly pallid livers.
What occurs in female mice that develop in utero between male fetuses?
Somewhat masculinized, with increased anogential distance and behavior.
Tissues of the adult uterine wall normally contain what cells? What influences their number?
Eosinophils. Wax and wane cyclically, disappear during pregnancy, and increase in number in response to semen.
What type of placentation do mice have?
Hemochorial.
Sexual maturity in males results in what sexually dimorphic features?
Larger kidneys, larger renal cortices, larger cells in proximal convoluted tubules, larger renal corpuscles, and cuboidal lining the parietal layer of Bowman’s capsule.
How does the adrenal gland of mice compare between the sexes?
Male mice adrenals tend to be smaller with less lipid than females
Describe accessory adrenals.
Common, in adrenal capsule or surrounding connective tissue.
Can the zona reticularis be distinguished from the fasciculata?
No
Proliferation of what cells of the adrenal gland, with displacement of the cortex, is common in mice of all ages?
Subcortical spindle cells. Function is unknown.
When does the X zone of the cortex appear?
Appears around 10 days of age.
What sexual difference occurs during involution of the X zone?
Marked vacuolation in females, but not in males
When does hematopoiesis occur in the spleen?
Throughout life in the red pulp, with increased hematopoiesis during disease and pregnancy resulting in splenomegaly.
Where does iron (hemosiderin) pigment tend to accumulate? In what animals?
Red pulp, especially in aged multiparous females.
Mast cells are frequently found in the spleen of which mouse strain?
A
How does the brain and spinal cord differ between sex?
Larger in males
What tissue can be found within the base of the aorta?
Cartilage or bone
Can non-pregnant females lactate?
Yes, can be induced to do so by the presence of other females nursing litters.
When is maternal IgG absorbed?
In utero through Fc yolk sac receptors and postnatally though IgG receptors in SI, which actively acquire Ig up to 2 weeks old.
Which Ig are found in milk, but not absorbed?
IgA and IgM.
For how long does maternal antibody generally persist?
6 weeks
Describe the Th1-Th2 polarized T-cell response.
Balb/c mice tend towards antigenic stimulate with a Th2 response and B6 mice with a Th1 response.
Describe IgG2c.
Found in B6, B10, SJL, and NOD. Distinct from IgG2a, which these strains lack.
How many histocompatibility loci does the mouse genome possess? Where are they located?
Approx 40, found on chromosome 17 within the MHC complex known as the H-2 complex. Each inbred strain has a defined H-2 haplotype, or combo of alleles which are recognized determinants of strain-specific immune responses.
What sexual and strain dimorphism exists with complement?
Males have a higher C4 and C5, while male SJL have higher C5.
SJL mice are deficient in what cell type?
NK
Which strains are unresponsive to LPS?
C3H/HeJ and C57BL/10ScN, due to mutation of TLR4.
All mice lack functional TLR10 due to what?
Genetic disruption by a retroviral insertion.
Which CBA mice have an X-linked defect in humoral immunity?
CBA/CaN
