Neoplastic and aging diseases of mice Flashcards
thymic LSA has a _____ incidence in ____ and ____ mice strains by 1 year and a high incidence in SCID mice
- near 100%
- AKR
- C58
Which mouse strain has a high incidence of multicentric lymphoma
BALB/c mice
Histiocytic sarcoma
- Predisposed strains
- Cell type of origin
- Aged B6 and SJL mice
- Kupffer cells and tissue macrophages
Gross findings of histiocytic sarcoma in mice
- enlargement and nodularity to spleen, liver, uterus, vagina, kidney, lung, and/or ovaries
Associated findings of histiocytic sarcoma
- erythrophagocytosis in HS arising from the liver
- Eosinophilic inclusions in renal tubular epithelium
Rat mammary tumors are often ___-containing, while mouse mammary tumors are made up of
- collagen
- epithelial cells
Gross findings of mammary neoplasia in mice
- often multicentric and multinodular, well-circumscribed (even if malignant)
- pale tan, firm, and may have areas of hemorrhage
- overlying skin may be ulcerated
- pulmonary metastasis possible
Histopath findings of mammary neoplasia in mice
- variably sized cystic structures lined by neoplastic glandular epithelium
- cells are pleomorphic
Strain susceptibility to Mammary neoplasia
- susceptible: C3H
- Resistant: BALB/c
predisposing factors to Mammary neoplasia
- MMTV, chemical carcinogens, and hormones influence incidence
- Prolactin, progesterone, and estrogens influence development
- Multiparous FVB mice are prone to mammary tumors
- Stress induces mammary neoplasia in C3H/He mice
Pulmonary neoplasia
- cell type of origin
- How do you classify adenoma vs. carcinoma
- clinical signs
- Arise from type II pneumocytes or Clara (club) cells
- classification based on tumor size
- usually no clinical signs
Strain susceptibility
- near 100% incidence in A strain mice by 18-24 mos.
Predisposing factors to pulmonary neoplasia
- enhanced incidence via Sendai virus or chemical carcinogens
Hepatocellular neoplasias are usually _________ or _____
What types are noted on histopath
hepatocellular adenomas or carcinomas
Note that there are trabecular or solid types on histopath
Strains predisposed to hepatocellular neoplasia
- A and DBA strains
Predisposing factors to Hepatocellular neoplasia
Helicobacter associated with earlier onset and higher prevalence in A strain mice
Harderian gland tumor
- Gross findings
- histopath findings
- behavior of neoplasm
gross:
- protrusion of the eye, porphyrin staining of periocular fur
Histopath
- lobulated, usually of papillary cystadenoma or solid adenoma morphology
- relatively well-differentiated epithelial cells with vacuolated cytoplams
behavior:
- adenocarcinomas are invasive but rare to metastasize
- Strains predisposed to osteomas and osteosarcomas
- most common site for vertebral tumors
- what virus can also lead to bone tumors in mice
strains
- NOD mice
- Outbred OF-1 and CF-1 mice develop benign bone tumors
Region:
- lumbosacral region is most common site for vertebral tumors
virus causing bone tumors
- PyV of nude mice
Pituitary gland adenomas
- Predisposed strains
- predisposed sex
- hormone produced by tumor
strains:
- common in B6 and Swiss mice
- FVB/N mice are very prone
Predisposed sex: females
- Hormone produce: prolactin
Gross findings of pituitary gland adenomas
Histopath findings
- large, pale tan to red, soft, well-demarcated mass, often very hemorrhagic
solid, sinusoidal, or cystic patterns on histopath
behavior: grow expansively with compression of the brain
Stain of choice for amyloidosis
Congo red
Amyloidosis:
- strains with high prevalence and early onset
- Strains with high prevalence but late onset
- strains that are rarely affected
- A, SJL, and outbred Swiss mice
- B6 and B10 mice
- BALB/C3H, and DBA mice
Strains predisposed to Soft tissue calcification
- BALB/c (right ventricular epicardial mineralization)
- C3H (Myocardium and ventricles and IVS, axial skeletal muscles)
- DBA (heart and many other organs)
You find acidophilic crystals accumulated with macrophages MNGCs, alveolar spaces, and airways. What is your first thought?
What are these crystals comprised of?
Acidophilic macrophage pneumonia
- Ym1 and Ym2 chitinase, with iron, alpha-1 antitrypsin
- Strains predisposed to acidophilic macrophage pneumonia
- predisposing factors°°
- B6, 129, and Swiss mice
- response to inflammation and/or diminished pulmonary clearance
You find similar crystals in the cytoplasm of olfactory, nasal respiratory, middle ear, trachea, lung, stomach, gallbladder, bile duct, and pancreatic duct epithelium. Now what do you call it?
“Epithelial hyalinosis”
What are some causes of hair loss in mice
- Barbering and trichotillomania (compulsive behavior/dominance issue)
- mechanical muzzle alopecia (improper food/watering tool use)
- Alopecia areata in C3H mice (autoimmune response)
- Alopecia of B6 mice (multifactorial and behavioral disorder)
- Clown syndrome (MHV infection on young mouse caused arrested hair follicle growth)
Common cause of Auricular chondritis
- autoimmune disease response to metal ID tagging
Causes of Gangrene of ears and limbs
- erosive inflammation and necrosis of pinnal margins (ears)
- Sloughing of extremeties due to cotton nesting material (limbs)
- frostbite (limbs, nude mice more at risk)
Ringtail (caused by low humidity and high temperature)
Hydrocephalus is relatively common in _____strains
C57BL strains
Acallosity and hypocallosity are common in which strains
- BALB/c and 129 mice
Microphthalmia/anophthalmia is common and unique to ____ mice strains
_____ are predisposed and it is usually _____, affecting the ______
- C57BL
- females
- asymmetric
- affecting the right eye
Which auricle is usually affected by atrial thrombosis
what are some predisposing factors
which strain is predisposed
the left auricle
predisposing factors:
- usually 2° to amyloidosis or renal disease
predisposed strain
- BALB/c
Murine Urologic Syndrome affects which strains predominantly
B6C3F1 and ICR strains
Pathogenesis of MUS
gross findings
proteinaceous plugs of ejaculate lodged in neck of urinary bladder or proximal urethra -> obstructive uropathy
urinary bladder distention, possible hydronephrosis
