Neuroprotection is improved by watertightness of fetal spina bifida repair in the sheep model.

OBJECTIVES: A contributing factor to unsuccessful prenatal spina bifida aperta (SBA) repair via an open approach may be incomplete neurosurgical repair causing persistent in-utero leakage of cerebrospinal fluid (CSF) and exposure of the fetal spinal cord to amniotic fluid. We aimed to investigate the neurostructural and neurofunctional efficacy of watertight prenatal SBA repair in a validated SBA fetal lamb model. METHODS: A well-powered superiority study was conducted in the validated SBA fetal lamb model (n = 7 per group). The outcomes of lambs which underwent watertight or non-watertight multilayer repair through an open approach were compared to those of unrepaired SBA lambs (historical controls) at delivery (term = 145 days). At ∼75 days, fetal lambs underwent standardized induction of lumbar SBA. At ∼100 days, they were assigned to an either watertight or non-watertight layered repair group based on an intraoperative watertightness test using subcutaneous fluorescein injection. At 1-2 days postnatally, as primary outcome, we assessed reversal of hindbrain herniation using magnetic resonance imaging (MRI). Secondary proxies of neuroprotection were: absence of CSF leakage at the repair site; hindlimb motor function based on joint-movement score, locomotor grade and Motor Evoked Potential (MEP); four-score neuroprotection scale, encompassing live birth, complete hindbrain herniation reversal, absence of CSF leakage and joint-movement score ≥ 9/15; and brain and spinal cord histology and immunohistochemistry. As the watertightness test cannot be used clinically due to its invasiveness, we developed a potential surrogate intraoperative three-score skin-repair-quality scale based on visual assessment of the quality of the skin repair (suture inter-run distance ≤ 3 mm, absence of tear and absence of ischemia), with high quality defined by a score ≥ 2/3 and low quality by a score < 2/3, and assessed its relationship with improved outcome. RESULTS: Compared with unrepaired lambs, lambs with watertight repair achieved a high level of neuroprotection (neuroprotection score of 4/4 in 5/7 vs 0/7 lambs) as evidenced by: a significant 100% (vs 14%) reversal of hindbrain herniation on MRI; low CSF leakage (14% vs 100%); better hindlimb motor function, with higher joint-movement score, locomotor grade and MEP area under the curve and peak-to-peak amplitude; higher neuronal density in the hippocampus and corpus callosum; and higher reactive astrogliosis at the SBA lesion epicenter. Conversely, lambs with non-watertight SBA repair did not achieve the same level of neuroprotection (score of 4/4 in 1/7 lambs) compared with unrepaired lambs, with: a non-significant 86% (vs 14%) reversal of hindbrain herniation; high CSF leakage (43% vs 100%); no improvement in motor function; low brain neuron count in both the hippocampus and corpus callosum; and small spinal astroglial cell area at the epicenter. Both watertight layered repair and high (≥ 2/3) intraoperative skin-repair-quality score were associated with improved outcome, but the watertightness test and skin-repair-quality scale could not be used interchangeably due to result discrepancies. CONCLUSIONS: Watertight layered fetal SBA repair is neuroprotective since it improves brain and spinal-cord structure and function in the fetal lamb model. This translational research has important clinical implications. A neurosurgical technique that achieves watertightness should be adopted in all fetal centers to improve neuroprotection. Future clinical studies could assess whether a high skin-repair-quality score (≥ 2/3) correlates with neuroprotection. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

The Pathology of Aging 129S6/SvEvTac Mice.

The 129 mouse strain is commonly used for the generation of genetically engineered mice. Genetic drift or accidental contamination during outcrossing has resulted in several 129 substrains. Comprehensive data on spontaneous age-related pathology exist for the 129S4/SvJae substrain, whereas only limited information is available for other 129 substrains. This longitudinal aging study describes the life span and spontaneous lesions of 44 male and 18 female mice of the 129S6/SvEvTac substrain. Median survival time was 778 and 770 days for males and females, respectively. Tumors of lung and Harderian gland were the most common neoplasms in both sexes. Hepatocellular tumors occurred mainly in males. Hematopoietic tumors were observed at low frequency. Suppurative and ulcerative blepharoconjunctivitis was the most common nonneoplastic condition in both sexes. Corynebacteria (primarily Corynebacterium urealyticum and C. pseudodiphtheriticum) were isolated from animals with blepharoconjunctivitis and in some cases from unaffected mice, although a clear causal association between corynebacterial infections and blepharoconjunctivitis could not be inferred. Polyarteritis occurred only in males and was identified as the most common nonneoplastic contributory cause of death. Eosinophilic crystalline pneumonia occurred in both sexes and was a relevant cause of death or comorbidity. Epithelial hyalinosis at extrapulmonary sites was noted at higher frequency in females. This study contributes important data on the spontaneous age-related pathology of the 129S6/SvEvTac mouse substrain and is a valuable reference for evaluation of the phenotype in genetically engineered mice obtained with this 129 substrain.

Immunohistological Description of Nongestational Ovarian Choriocarcinoma in Two Female Mice With Conditional Loss of Trp53 Driven by the Tie2 Promoter.

Nongestational ovarian choriocarcinoma (NGCO) is a tumor of germ cell origin seldom described in nonhuman species. Few spontaneous cases are reported in macaques and mice, with the B6C3F1 strain overrepresented. This report describes 2 cases of ovarian choriocarcinoma in nulliparous female mice with conditional loss of Trp53 under the Tie2 promoter. The mouse line was maintained on a mixed genetic background including Crl: CD1(ICR) and 129X1/SvJ strains. In both cases, affected ovary was partially replaced by blood-filled lacunae lined by neoplastic trophoblast-like giant cells. Immunohistochemically, neoplastic cells expressed folate-binding protein and prolactin and were invariably negative for p53. To the authors' knowledge, this is the first report characterizing this entity in a genetically engineered mouse (GEM) line. Considering that germ cells (the cell population from which NGCO originates) constitutively express Tie2 receptor, it can be speculated that Tie2-driven deletion of Trp53 may have played a role in the development of these tumors.

Diffuse scaling dermatitis in an athymic nude mouse.

This report describes the clinicopathological features of a case of diffuse scaling dermatitis that occurred in a 16-week-old female athymic nude (CrTac:NCr-Foxn1(nu)) mouse. Gross presentation was suggestive of Corynebacterium bovis infection (scaly skin disease). However, C. bovis was not isolated from the skin of the affected animal or from the skin of unaffected CrTac:NCr-Foxn1(nu) mice housed in the same cage or room. Staphylococcus xylosus was instead isolated in high numbers from the skin lesion, whereas only a few colonies were recovered from the skin of unaffected mice. Microscopically, the affected skin was characterized by chronic hyperplastic and hyperkeratotic dermatitis with focal ulcerations, extensive serocellular crusts, and intralesional clusters of Gram-positive coccoid bacteria. Although gross presentation of the reported case was suggestive of C. bovis infection, epidemiological, histopathological, and bacteriological findings definitively ruled out an outbreak of scaly skin disease. A diagnostic hypothesis of hyperplastic and hyperkeratotic dermatitis associated with opportunistic S. xylosus infection was formulated based on increased bacterial burden and presence of intralesional Gram-positive coccoid bacteria.

Diagnostic exercise: sudden death in a mouse with experimentally induced acute myeloid leukemia.

A 22-week-old female 129/SvEv mouse suddenly died in the context of an experiment aimed at defining the efficacy of valproic acid in a mouse model of PML/RARalpha-induced acute myeloid leukemia. Histologic analysis confirmed the mouse as being affected by a progressive myeloid leukemia, with infiltration of the spleen, bone marrow, liver, kidneys, and lungs. Variably sized intravascular clumps (emboli) of dense basophilic material admixed with necrotic or lytic neoplastic cells were also observed in multiple organs. A positive reaction to Feulgen and Hoechst stain confirmed the high content in chromatin of these basophilic emboli. Cleaved caspase-3 activity was demonstrated both in the leukemic infiltrates and among the intravascular necrotic or lytic neoplastic cells accompanying the basophilic emboli. A diagnosis of acute tumor lysis syndrome related to therapy-induced massive necrosis and/or apoptosis of leukemic cells with subsequent dissemination of emboli of chromatin was proposed.

Mammary tumor phenotypes in wild-type aging female FVB/N mice with pituitary prolactinomas.

Prolactin-secreting pituitary adenomas are common spontaneous lesions in aging FVB females. Prolactin-secreting pituitary proliferations play a significant role in mouse mammary tumorigenesis generally producing adenosquamous carcinomas. Since genetically engineered FVB mice are frequently used to study mammary tumor biology, we have examined a cohort of 64 aging wild-type FVB/N females to establish the prevalence and the nature of spontaneous mammary and pituitary tumors. Tissues from mammary and pituitary glands were studied by histopathology and immunohistochemistry. Of the 64 examined mice, 20 had pituitary tumors and 20 had mammary tumors. Mammary and pituitary tumors were associated in 17 mice. All pituitary tumors were prolactin-positive by immunohistochemistry and classified as prolactinomas. Fourteen mammary tumors, including 12 cases with and 2 without concurrent prolactinomas, were adenocarcinomas with different combinations of epithelial growth patterns. Five mice with prolactinomas had mammary tumors characterized by the epithelial-mesenchymal transition (EMT) phenotype. Estrogen receptor alpha (ERalpha)-positivity was observed for 14 of the 18 mammary tumors tested, including both adenocarcinomas with nuclear immunoreactivity and EMT-phenotype tumors with both nuclear and cytoplasmic immunoreactivity. No immunoreactivity for the progesterone receptor was observed. This study confirms that spontaneous prolactinomas and mammary tumors are both common and significantly associated lesions in FVB mice. Parity and age represented risk factors for the development of these tumors. Compared with previous reports, prolactinoma-associated mammary tumors displayed a broader morphologic spectrum, including cases with the EMT phenotype. The elevated number of prolactinoma-associated and ERalpha-positive mammary tumors opens intriguing possibilities concerning the role of ERalpha cytoplasmic localization during EMT tumorigenesis.

Expression of major histocompatibility complex class II antigens in porcine leptospiral nephritis.

Class II major histocompatibility complex (MHCII) is required for the presentation of antigens to CD4 helper T cells. During nephritis, not only primary antigen presenting cells such as histiocytes and lymphocytes, but also cytokine-stimulated tubular epithelial cells express MHCII. Leptospirosis in fattening pigs is characterized by several degrees of nephritis, from absence of lesions to severe multifocal tubulo-interstitial inflammation. Renal tissue from 20 8-month-old pigs with spontaneous nephritis and 6 control pigs without renal lesions were investigated for leptospirosis by indirect immunohistochemistry (IHC) and polymerase chain reaction (PCR). IHC for MHCII also was performed on renal samples. Serum samples were tested for different serovars of Leptospira interrogans. Control pigs were free of interstitial nephritis and negative for leptospirosis by all tests. In pigs with nephritis, serology was positive for serovar Pomona in 19/20 pigs. In 16 of these 19 pigs, leptospiral renal infection was confirmed by PCR and/or indirect IHC. Nephritic lesions were classified histologically into perivascular lymphocytic (4 pigs), lymphofollicular (6 pigs), lymphohistiocytic (8 pigs), and neutrophilic (2 pigs) pattern. MHCII expression by histiocytes and lymphocytes was observed in all lesions. Prominent MHCII expression in regenerating tubular epithelium was observed in lymphofollicular and lymphohistiocytic nephritis. No tubular colocalization between leptospiral and MHCII antigen was observed. Results suggest that during leptospiral nephritis, MHCII contributes to the intensity of the inflammatory response. Furthermore de novo MHCII expression in regenerating tubules may play a role in the defence mechanism against leptospiral tubular colonization.

Rhabdomyosarcoma of the pectoral muscles of a free-living European robin (Erithacus rubecula).

An adult free-living European robin (Erithacus rubecula) with a large, firm, subcutaneous mass on the pectoral muscle was examined. The bird was unable to fly and died spontaneously. Necropsy revealed a yellowish, bilobate mass almost completely replacing the pectoral muscles with extensive osteolysis of the keel bone. Histopathology revealed a poorly demarcated, highly cellular sarcomatous tumour with metastases to the lungs, pulmonary blood vessels and heart. Immunohistochemistry was negative for neuron-specific enolase, S-100 protein and the p-27 major capsid protein of avian leukosis viruses. The homogeneously positive immunolabelling for vimentin and scattered positivity for myoglobin and desmin suggested a diagnosis of rhabdomyosarcoma. A retrospective examination of the records for 194 birds of the thrush family, including 64 robins submitted over a 20-year period, showed no diagnoses of neoplasia.

Bacteriological, serological, pathological and immunohistochemical studies of Mycoplasma bovis respiratory infection in veal calves and adult cattle at slaughter.

Mycoplasma bovis is an important cause of calf pneumonia worldwide. In this study, we examined 140 cattle at slaughter comprising 70 veal calves and 70 beef cattle; 115 animals with pneumonic lesions and 25 without. Lung samples were submitted for bacteriological, histological, and M. bovis-immunohistochemical analyses. Serology for M. bovis was positive in 76% of beef cattle and 100% of veal calves. M. bovis was isolated only from veal calves in 16 out of 64 pneumonic cases. M. bovis was detected by immunohistochemistry in seven bacteriologically positive cases. M. bovis antigen was associated with bronchogenic necrosuppurative or fibrinonecrotizing lesions. Bacteriologically positive and immunohistochemical negative cases were associated with catarrhal bronchointerstitial pneumonia. Results suggest that M. bovis infection may develop into a severe necrosuppurative bronchopneumonia or fibrinonecrotizing pneumonia when associated with a high number of intralesional organisms or, conversely, into a mild catarrhal bronchointerstitial pneumonia when associated with a low number of organisms.

Mutations in LZTR1 drive human disease by dysregulating RAS ubiquitination.

The leucine zipper-like transcriptional regulator 1 (LZTR1) protein, an adaptor for cullin 3 (CUL3) ubiquitin ligase complex, is implicated in human disease, yet its mechanism of action remains unknown. We found that Lztr1 haploinsufficiency in mice recapitulates Noonan syndrome phenotypes, whereas LZTR1 loss in Schwann cells drives dedifferentiation and proliferation. By trapping LZTR1 complexes from intact mammalian cells, we identified the guanosine triphosphatase RAS as a substrate for the LZTR1-CUL3 complex. Ubiquitome analysis showed that loss of Lztr1 abrogated Ras ubiquitination at lysine-170. LZTR1-mediated ubiquitination inhibited RAS signaling by attenuating its association with the membrane. Disease-associated LZTR1 mutations disrupted either LZTR1-CUL3 complex formation or its interaction with RAS proteins. RAS regulation by LZTR1-mediated ubiquitination provides an explanation for the role of LZTR1 in human disease.

Effects of warfarin on thrombosis of the jugular veins of rabbits induced by prolonged stasis.

We have studied the effects of warfarin pretreatment on blood coagulation tests, thrombosis and endothelial damage in the rabbit after 2 h of subsequent venous stasis. We found that 3 mg/kg warfarin significantly modified the results of prothrombin time, activated partial thromboplastin time and ProComplex tests. The incidence of thrombosis was not reduced by warfarin, but the weight of the thrombi were inversely related to the effects of the drug on blood coagulation. The endothelial cells showed some degree of damage. In conclusion, warfarin neither prevents endothelial damage nor reduces the incidence of thrombosis after venous stasis, but retards the growth of thrombi.

The effects of L-sulpiride on reflux oesophagitis.

Prokinetic drugs are commonly used for treatment of reflux oesophagitis. Although much data has been collected in clinical trials, their therapeutic effects are still uncertain. In this study the effects of L-sulpiride, if any, were examined when used to treat reflux oesophagitis in thirty patients. The patients were divided into two groups: a control group and a group given 25 mg t.i.v./day, p.o. of L-sulpiride for 30 days. They were treated as outpatients and had endoscopic, histological and ultrastructural examinations on the 30th and 60th days of treatment. It was found that the symptoms of patients with reflux oesophagitis were alleviated and the endoscopic and ultrastructural lesions of patients with minor oesophagitis were also decreased. In other patients, symptoms improved without resolution of the lesions. The authors conclude, therefore, that L-sulpiride would be appropriate treatment for Grade I cases.

The role of mast cells in wound healing.

Mast cells are known to participate in three phases of wound healing: the inflammatory reaction, angiogenesis and extracellular-matrix reabsorption. The inflammatory reaction is mediated by released histamine and arachidonic acid metabolites. Compound 48/80 and disodium-cromoglycate are both able to increase skin breaking strength shortly after wounding. Under light and electron microscopy we found that small, granule-poor, irregular mast cells (MLMC) accumulate in the wound. This suggests that the small MLMC (mucosal-like mast cells) migrate into the skin during wound healing, and that both CTMC (connective-tissue mast cells) and MLMC are involved in tissue repair. Moreover, there is some evidence that mast cells participate in angiogenesis, since heparin is able to stimulate endothelial-cell migration and proliferation in vitro, and protamine to inhibit these processes and also angiogenesis in vivo. When the effect of protamine on wound breaking strength was examined, we encountered a decrease which was not prevented by heparin administration. Further studies are needed to demonstrate that protamine is specifically involved in inhibiting heparin-mediated angiogenesis in wounded tissue. Finally, mast cells may play a role in the extracellular matrix remodelling, on the basis of in-vitro experiments (but there are still no in-vivo data).

The effects of oxygen free radicals on wound healing.

We have examined the effects of oxygen free radicals, generated by xenobiotics administration, ischaemia-reperfusion or sepsis, on the healing of skin or intestinal wounds in rats. We found that 5 days after operation there was a significant decrease in the wound breaking strength in rats treated with phenazine methosulfate, zymosan, ischaemia-reperfusion or retroperitoneal infection. These changes were specifically prevented by administration of superoxide-dismutase (SOD), aprotinin and (in some models) allopurinol. On the contrary, none of these measures was effective when a local trauma caused the decrease in breaking strength. Our results suggest that oxygen free radicals mediate the inhibition of wound healing following ischaemia-reperfusion and sepsis.

Hyaluronic acid prevents oxygen free-radical damage to granulation tissue: a study in rats.

Oxygen free-radicals are known to impair wound healing after ischaemia-reperfusion or polymorphonuclear cell stimulation. Furthermore, they reduce the breaking strength of all recent wounds and might be a cause of wound leakage. This study was performed to evaluate whether or not hyaluronic acid can reduce the risk of wound impairment caused by free-radicals, in rats with abdominal sepsis, polymorphonuclear cell stimulation or cytochrome C function derangement produced by xenobiotics. Male Sprague-Dawley rats with open wounds received phenazine methosulfate or zimosan, or had abdominal sepsis to induce oxygen free-radical generation. There were three groups of treatment: hyaluronic acid cream, hyaluronic acid ethyl ester gel, and placebo. The reduction in wound size was measured from the 1st to the 11th postoperative day; biopsies were taken for histological evaluation. Every other day, a gentle debridement was performed in all the groups of animals. We found that hyaluronic acid and its ethyl ester derivative significantly improved the wound healing of rats subjected to an increased generation of oxygen free-radicals. It remains to be established whether or not hyaluronic acid acts as a scavenger of free-radicals.

[Potential and limitations of conservative surgery in the treatment of gastric stump cancer]. / Possibilità e limiti della chirurgia conservativa nel trattamento del cancro del moncone gastrico.

In the Italian population the risk of gastric stump cancer after surgery for peptic ulcer is increased after 20-30 years. Bearing in mind that further surgery has little curative chances, we examined the series seen at the Institute of General Surgery of the University of Milan (1983-1992) to investigate whether or not patients followed-up endoscopically have a better chance of cure after surgery. Although only 10 patients were available for evaluation, it was evident that patients found at endoscopic screening in stage 0 and I (UICC classification) had a good survival after surgery. Our results support the need of strict endoscopic follow-up of resected patients 20 or more years after surgery and the need of further investigations to establish whether or not resection is useful and safe for early lesions.

RNF4 is required for DNA double-strand break repair in vivo.

Unrepaired DNA double-strand breaks (DSBs) cause genetic instability that leads to malignant transformation or cell death. Cells respond to DSBs with the ordered recruitment of signaling and repair proteins to the sites of DNA lesions. Coordinated protein SUMOylation and ubiquitylation have crucial roles in regulating the dynamic assembly of protein complexes at these sites. However, how SUMOylation influences protein ubiquitylation at DSBs is poorly understood. We show herein that Rnf4, an E3 ubiquitin ligase that targets SUMO-modified proteins, accumulates in DSB repair foci and is required for both homologous recombination (HR) and non-homologous end joining repair. To establish a link between Rnf4 and the DNA damage response (DDR) in vivo, we generated an Rnf4 allelic series in mice. We show that Rnf4-deficiency causes persistent ionizing radiation-induced DNA damage and signaling, and that Rnf4-deficient cells and mice exhibit increased sensitivity to genotoxic stress. Mechanistically, we show that Rnf4 targets SUMOylated MDC1 and SUMOylated BRCA1, and is required for the loading of Rad51, an enzyme required for HR repair, onto sites of DNA damage. Similarly to inactivating mutations in other key regulators of HR repair, Rnf4 deficiency leads to age-dependent impairment in spermatogenesis. These findings identify Rnf4 as a critical component of the DDR in vivo and support the possibility that Rnf4 controls protein localization at DNA damage sites by integrating SUMOylation and ubiquitylation events.

Congenital mesoblastic nephroma in a young basset hound dog.

An 18-month-old male basset hound was presented with vomiting, diarrhoea and depression. Abdominal ultrasonography revealed a mass in the left kidney. An ultrasound-guided core-biopsy indicated aggregates of spindle cells, but did not allow a definitive diagnosis. Nephrectomy was performed after a period of six months, when ultrasound examination revealed a slight increase in mass dimensions. Histologically the mass was composed of neoplastic spindle cells forming interlacing fascicles, bundles and whorls, within a loose myxoid to dense collagenous stroma. Immunohistochemically neoplastic cells were positive for vimentin and smooth muscle actin. Based on these findings the tumour was diagnosed as a congenital mesoblastic nephroma, classical variant. After a two-and-a-half-year follow-up the dog was clinically healthy, indicating a benign behaviour. To the authors' knowledge, this report describes the first case of canine congenital mesoblastic nephroma successfully treated surgically, with a reasonable postsurgical follow-up.

Development of tertiary lymphoid structures in the kidneys of pigs with chronic leptospiral nephritis.

Tertiary lymphoid organs (TLOs) are structures that are morphologically and functionally similar to secondary lymphoid organs. TLOs usually arise in a background of chronic inflammation. Several histological patterns of interstitial nephritis have been documented in porcine leptospirosis. Among them the lympho-follicular pattern is characterized by infiltrates of mononuclear cells organized in lymphoid follicle-like structures. Immunohistological analysis of 5 cases of porcine lympho-follicular nephritis associated with Leptospira Pomona infection demonstrated the presence of inflammatory cell populations, including B cells, T cells, macrophages and follicular dendritic cells (FDCs), which were compartmentalized as in TLOs. Immunohistochemistry for Leptospira Pomona revealed an intimate association between leptospiral antigen and FDCs. Overexpression of MHCII in different populations of both professional and non-professional antigen presenting cells was also demonstrated. FDCs play role during TLOs induction for their ability to retain non-self antigens in the form of immune complexes, thus causing persistent T cell activation, generation of a complex cytokine network and stimulation of humoral immunity. Sustained bacterial antigen presentation in the context of chronic leptospiral nephritis, may also lead to autoimmune mechanisms involved in the generation of TLOs. Whether lymphoid neogenesis and TLOs play a protective role in porcine leptospiral nephritis is still unclear.

Clinical, pathological and immunological features of psoriatic-like lesions affecting keratin 14-vascular endothelial growth factor transgenic mice.

Up-regulation of vascular endothelial growth factor (VEGF) plays a primary role in the pathogenesis of psoriasis. Transgenic mice over-expressing VEGF under the Keratin 14 (K14) promoter develop an inflammatory skin condition with many of the pathobiological features of human psoriasis. In this work, the development of spontaneous psoriatic-like dermatitis in K14-VEGF transgenic mice was monitored from week 6 to week 44 and skin lesions were characterized clinically (application of a clinical score system comparable to the human Psoriasis Area and Severity Index), microscopically (histopathology, leukocyte subset and neoangiogensis) and immunologically (evaluation of local and systemic cytokine/chemokine profiles). Based on PASI score system, three progressive clinical phases were identified: mild acute (8-14 weeks of age), moderate subacute (15-21 weeks of age) and severe chronic-active (22-44 weeks of age) dermatitis. Microscopically, skin lesions consisted of progressive proliferative psoriatic-like dermatitis dominated by dermo-epidermal infiltrates of CD3-positive lymphocytes, an increased number of mast cells and neoangiogenesis. Both local and systemic up-regulation of pro-inflammatory (IL-12, TNF-alpha, IL-6, MCP-1 and IL-8) and regulatory (IL-10) cytokines/chemokines was observed, mainly during the later stages of disease development. The results obtained in this study further confirm the central role of VEGF over-expression in the development of psoriatic-like dermatitis. Similarly to what is reported for human psoriasis, both the local and systemic immunologic profiles observed in K14-VEGF transgenic mice suggest that a combined Th1 and Th17 response may be implicated in lesion development. The identification of three progressive stages of disease, each with peculiar clinicopathological features, renders the K14-VEGF transgenic mouse a valuable model to study novel immunotherapies for psoriasis.