Seroreactivity against PTEN-induced putative kinase 1 (PINK1) in Turkish patients with Behçet's disease.

BACKGROUND: Behçet's disease (BD) is a multisystem inflammatory disorder characterized by recurrent oral ulcers, genital ulcers and ocular inflammation, as well as skin, joint, vascular, pulmonary, central nervous system (CNS) and gastrointestinal tract manifestations. The etiopathogenesis of BD has not yet been identified; but it has generally been accepted that several environmental factors may induce an inflammatory attack in genetically susceptible individuals. In this study, we aimed to identify antigens that could elicit high-titer IgG responses by the serological analysis of recombinant expression of cDNA libraries method (SEREX). METHODS: We screened a human testis cDNA library with pooled sera obtained from 4 BD patients by SEREX. Antigens that were identified with the initial analysis were selected for seroreactivity analysis of a larger group of BD patients (n=78) and controls (n=66) by serological immunoscreening. RESULTS: We observed seroreactivity against 6 antigens using the pooled sera. These included rabaptin 5 (RABPT5), PTEN-induced putative kinase 1 (PINK1), switch associated protein 70 (SWAP70), interferon-induced protein with tetratricopeptide repeats 2 (IFIT2), ankyrin repeat domain 20 family, member A1 (ANKRD20A1), and an unknown antigen. Eleven out of 82 (13.4%) BD patients were found to have antibodies elicited against PINK1 antigen, when none of the control sera showed reactivity (p=0.001). There was no significant difference in the frequency of other defined antigens between the patient and control groups. However, among BD clinical sub-groups, anti-SWAP70 antibodies were found to associate with vascular involvement. DISCUSSION: In this study, antibodies against PINK1 were found to specifically associate with BD while SWAP70 antibody was associated with clinical sub-groups of BD. Although variations in both genetic background and environmental factors may affect the outcome of serological responses, our results suggest that serological screening can be used to identify antigens that elicit antibody responses associated with BD.

SOX1 antibodies are markers of paraneoplastic Lambert-Eaton myasthenic syndrome.

BACKGROUND/OBJECTIVE: We reported that 43% of patients with Lambert-Eaton myasthenic syndrome (LEMS) and small cell lung cancer (SCLC) had an antibody called anti-glial nuclear antibody (AGNA), defined by the immunoreaction with the nuclei of the Bergmann glia of the cerebellum. This study was undertaken to identify the antigen recognized by AGNA and to confirm the association with paraneoplastic LEMS in a larger series. METHODS: We probed a fetal brain cDNA library with AGNA-positive sera. The presence of antibodies against the isolated antigen was detected by immunoblot of phage plaques from two positive clones. We studied 105 patients with LEMS (55 with SCLC), 50 with paraneoplastic neurologic syndromes, SCLC, and Hu antibodies, and 50 with only SCLC. RESULTS: Probing of the fetal brain expression library with AGNA sera resulted in the isolation of SOX1, a highly immunogenic tumor antigen in SCLC. IgG eluted from SOX1 clones produced the same cerebellar immunoreactivity as of AGNA sera. SOX1 antibodies were present in 64% of patients with LEMS and SCLC but in none of the 50 with idiopathic LEMS (p < 0.0001). Compared with paraneoplastic LEMS, the frequency of SOX1 antibodies was significantly lower in patients with Hu antibodies (32%, p = 0.002) and in those with only SCLC (22%). CONCLUSIONS: SOX1 is the antigen recognized by anti-glial nuclear antibody-positive sera. The detection of SOX1 antibodies in patients with Lambert-Eaton myasthenic syndrome (LEMS) predicts the presence of small cell lung cancer and may be used to follow more closely those LEMS patients with no evidence of cancer at the initial workup.

Use of technetium-99m HMPAO scintigraphy for the detection of amiodarone lung toxicity in a rabbit model.

Amiodarone (AD) is a very effective anti-arrhythmic drug, but its use is often associated with serious pulmonary complications such as pneumonitis and interstitial pulmonary disease. The aim of this study was to investigate the relationship between the amount of amiodarone intake (and the related development of lung toxicity) and the lung uptake of technetium-99m labelled D,L-hexamethylpropylene amine oxime (HMPAO). Eighteen white female New Zealand rabbits were divided into three groups and fed AD by gavage at doses of 10 (group A), 50 (group B) or 150 (group C) mg/kg daily. 99mTc-HMPAO scintigraphy was performed at baseline and after 1, 2, 3 and 4 weeks of drug intake. Anterior images of 1 min duration were acquired at 30 min after the injection of 37 MBq 99mTc-HMPAO. Regions of interest (ROIs) were drawn on the lungs (L) and the upper limb (B) as the background. L/B ratios were calculated using the mean counts. In groups A and B histopathological evaluation of the lungs of all rabbits was performed at the end of the 4 weeks of AD intake, while in group C it was performed at 2 weeks because of increased mortality. At baseline, mean L/B ratios for groups A, B and C were 2.8 +/- 0.3, 2.8 +/- 0.3 and 2.8 +/- 0.4, respectively. After 3 weeks of AD intake, L/B ratios increased to 4.1 +/- 0.6 and 4.8 +/- 0.6 in groups A and B, respectively. The L/B ratio was 3.6 +/- 0.2 after 1 week of AD intake in group C. The correlation coefficients between the lung uptake of 99mTc-HMPAO and AD doses for groups A, B and C were r = 0.51 (P = 0.037), r = 0.74 (P = 0.0002) and r = 0.96 (P = 0.0001), respectively. Histopathological findings related to AD lung toxicity, such as interstitial pneumonitis and foamy alveolar macrophages, were observed more frequently in groups B and C than in group A. According to our findings, 99mTc-HMPAO lung uptake is correlated with AD dose. 99mTc-HMPAO lung imaging can demonstrate AD-induced lung injury.

Identification of a tissue-specific putative transcription factor in breast tissue by serological screening of a breast cancer library.

Application of SEREX (serological analysis of recombinant tumor cDNA expression libraries) to different tumor types has led to the identification of several categories of human tumor antigens. In this study, the analysis of a breast cancer library with autologous patient serum led to the isolation of seven genes, designated NY-BR-1 through NY-BR-7. NY-BR-1, representing 6 of 14 clones isolated, showed tissue-restricted mRNA expression in breast and testis but not in 13 other normal tissues tested. Among tumor specimens, NY-BR-1 mRNA expression was found in 21 of 25 breast cancers but in only 2 of 82 nonmammary tumors. Structural analysis of NY-BR-1 cDNA and the corresponding genomic sequences in the recently released working draft of human genome indicated that NY-BR-1 is composed of 37 exons and has an open reading frame of 4.0-4.2 kb, encoding a peptide of Mr 150,000-160,000. A bipartite nuclear localization signal motif indicates a nuclear site for NY-BR-1, and the presence of a bZIP site (DNA-binding site followed by leucine zipper motif) suggests that NY-BR-1 is a transcription factor. Additional structural features include five tandem ankyrin repeats, implying a role for NY-BR-1 in protein-protein interactions. NY-BR-1 thus represents a breast tissue-specific putative transcription factor with autoimmunogenicity in breast cancer patients. In addition to NY-BR-1, a homologous gene, NY-BR-1.1, was identified in this study. NY-BR-1.1 shares 54% amino acid homology with NY-BR-1 and also shows tissue-restricted mRNA expression. However, unlike NY-BR-1, NY-BR-1.1 mRNA is expressed in brain, in addition to breast and testis. The exon structure of NY-BR-1.1 remains to be defined. Using human genome database, NY-BR-1 was localized to chromosome 10p11-p12, and NY-BR-1.1 was tentatively localized to chromosome 9.

Erythropoietin exerts neuroprotection in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated C57/BL mice via increasing nitric oxide production.

Erythropoietin (EPO), produced by the kidney and fetal liver, is a cytokine-hormone that stimulates erythropoiesis under hypoxic conditions. It has been shown that EPO is produced in the central nervous system and its receptor is expressed on neurons. Since EPO has neuroprotective effects in vitro and in vivo against brain injury, we investigated the effect of EPO treatment on locomotor activities of animals, survival of nigral dopaminergic neurons and nitrate levels in substantia nigra and striatum in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced animal model of Parkinsonism in C57/BL mice. Our findings suggest that EPO has protective and treating effect in MPTP-induced neurotoxicity in this mouse model of Parkinson's Disease via increasing nitric oxide production.

Methamphetamine causes depletion of glutathione and an increase in oxidized glutathione in the rat striatum and prefrontal cortex.

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. The hypothesis that methamphetamine-induced neurotoxicity is mediated by reactive oxygen species was evaluated. It was found that acute administration of methamphetamine (5 and 15 mg kg(-1)) resulted in production of oxidative stress as demonstrated by decreased glutathione and increased oxidized glutathione levels in the rat striatum and prefrontal cortex. These changes in glutathione and oxidized glutathione levels were dose-dependent in striatum but not in prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.

Humoral immunity to human breast cancer: antigen definition and quantitative analysis of mRNA expression.

The ability of the immune system to recognize structurally altered, amplified or aberrantly expressed proteins can be used to identify molecules of etiologic relevance to cancer and to define targets for cancer immunotherapy. In the current study, ninety-four distinct antigens reactive with serum IgG from breast cancer patients were identified by immunoscreening breast cancer-derived cDNA expression libraries (SEREX). A serological profile was generated for each antigen on the basis of reactivity with allogeneic sera from normal individuals and cancer patients, and mRNA expression profiles for coding sequences were assembled based upon the tissue distribution of expressed sequence tags, Northern blots and real-time RT-PCR. Forty antigens reacted exclusively with sera from cancer patients. These included well-characterized tumor antigens, e.g. MAGE-3, MAGE-6, NY-ESO-1, Her2neu and p53, as well as newly-defined breast cancer antigens, e.g. kinesin 2, TATA element modulatory factor 1, tumor protein D52 and MAGE D, and novel gene products, e.g. NY-BR-62, NY-BR-75, NY-BR-85, and NY-BR-96. With regard to expression profiles, two of the novel gene products, NY-BR-62 and NY-BR-85, were characterized by a high level of testicular mRNA expression, and were overexpressed in 60% and 90% of breast cancers, respectively. In addition, mRNA encoding tumor protein D52 was overexpressed in 60% of breast cancer specimens, while transcripts encoding SNT-1 signal adaptor protein were downregulated in 70% of these cases. This study adds to the growing list of breast cancer antigens defined by SEREX and to the ultimate objective of identifying the complete repertoire of immunogenic gene products in human cancer (the cancer immunome).

Leukocyte activation, oxidant stress and red blood cell properties after acute, exhausting exercise in rats.

Red blood cell (RBC) mechanical alterations and oxidative damage were investigated after an acute exhausting exercise in rats, together with the leukocyte activation. The groups formed as follows. Control (C) (n = 9), group I (n = 9) and group II (n = 7) from which blood samples were collected 15 minutes and 24 hours respectively, after acute exercise. The rats were subjected to running at a speed of 17 m/min until exhaustion. The leukocyte phagocytic activity (LPA), RBC lipid peroxidation and RBC deformability were measured. LPA increased significantly after the exhausting exercise and prolonged till 24 hours (p = 0.0168). RBC membrane lipid peroxidation was gradually increased till 24 hours (p = 0.0297) and there was a significant correlation between LPA and RBC lipid peroxidation (r = 0.63, p = 0.015). There was a slight but significant decrease in mean corpuscular volume (MCV) (p = 0.0467) and increase in mean corpuscular hemoglobin concentration (MCHC) (p = 0.0458) suggesting a cellular dehydration after 24 hours. No significant alteration was detected in RBC deformability, assessed by the Cell Transit Analyzer (CTA) and thought that decreased MCV might have masked to determine the alterations in membrane mechanical properties in CTA. As a conclusion the results imply that activated leukocytes might play role in the RBC damage observed after exhausting exercise encouraging oxidative stress.

The effects of single dose of methamphetamine on lipid peroxidation levels in the rat striatum and prefrontal cortex.

The administration of methamphetamine to experimental animals results in damage to dopaminergic neurons. In the present study, we demonstrated that a single dose (15 mg/kg) of methamphetamine results in production of oxidative stress as demonstrated by increased thiobarbituric acid reactive substances levels in the rat striatum and prefrontal cortex. In conclusion, the results of present study provide further evidence in support of the notion that oxidative stress may play an important role in the methamphetamine-induced neurotoxicity.

Serological cloning of a melanocyte rab guanosine 5'-triphosphate-binding protein and a chromosome condensation protein from a melanoma complementary DNA library.

Characterization of immunogenic human melanoma antigens has been a major focus of tumor immunologists over the past two decades, and a broad array of antigens recognized by antibodies and T cells in the autologous host has been defined. In the present study, a melanoma library was screened by SEREX (serological analysis of cDNA expression libraries), and 43 genes were isolated, 2 of which, NY-MEL-1 and NY-MEL-3, encode novel gene products with differential tissue expression. NY-MEL-1 encodes a new rab GTP-binding protein, rab38. Among >40 rab proteins, rab38 has a unique COOH terminus which would allow posttranslational farnesylation and palmitoylation, lipid modifications normally occurring in ras proteins but not in other rab proteins. It is also the only rab gene showing a predominant mRNA expression in melanocytes, a cell-specific expression pattern likely related to melanosomal transport and docking. Northern blot analysis showed no detectable expression in other normal tissues. Consistent with this lineage specificity, rab38 mRNA is expressed in 80-90% of melanoma (17 of 19), but rarely in nonmelanocytic malignancies (1 of 16). The second novel gene isolated, NY-MEL-3, encodes a mitotic protein highly homologous to the Xenopus chromosome condensation protein XCAP-G, designated hCAP-G. Analysis of hCAP-G mRNA expression showed highest expression in the testis among normal tissues and variable expression in tumor cells, reflecting the proliferative activity in these cells. This mitosis-related expression suggests hCAP-G as a possible proliferation marker and a potential prognostic indicator in cancer. These findings provide further support that SEREX can define biologically significant molecules in cancer.

Effects of prenatal ethanol exposure on neuronal migration, neuronogenesis and brain myelination in the mice brain.

BACKGROUND: One of the most severe consequences of maternal alcohol consumption is the damage to the developing central nervous system. MATERIAL AND METHODS: To evaluate the effect of prenatal alcohol exposure on neuronal migration, neuronogenesis and myelination in the brain, pregnant BALB/C mice were maintained on either liquid diets containing ethanol (12 g/kg body weight) beginning on gestation day 6 or isocoloric diet (control group). The dams were sacrificed on gestation day 17 and the brain sections of the pups were analyzed using immunohistochemical method to evaluate the number of neurons, oligodendrioglial expression of myelin basic protein (MBP) and neuronal expression of neural cell adhesion molecule (NCAM). RESULTS: Ethanol-exposed pups revealed significantly weaker expression of MBP compared to the control group. In contrast, no significant difference of NCAM expression and neuronal cell count were present between ethanol-exposed pups and the control group. CONCLUSION: These data demonstrate that alcohol exposure affects the level of MBP expression, consequently causing a reduction in brain myelination that may lead to neuronal dysfunction. The ineffectiveness of prenatal alcohol exposure on the number of neurons in contrast to the previous reports might be due to the adequate sampling of areas for cell counting. Although there is a view that NCAM is involved both directly and indirectly in neuronal cell migration, we speculate that alcohol neuroembryotoxicity uncouples this relationship. Other adhesion molecules, such as L1, or extracellular matrix proteins, such as laminin, would be other candidates for investigation.

Serological identification of embryonic neural proteins as highly immunogenic tumor antigens in small cell lung cancer.

Serological analysis of expression cDNA libraries (SEREX) derived from two small cell lung cancer (SCLC) cell lines using pooled sera of SCLC patients led to the isolation of 14 genes, including 4 SOX group B genes (SOX1, SOX2, SOX3, and SOX21) and ZIC2. SOX group B genes and ZIC2 encode DNA-binding proteins; SOX group B proteins regulate transcription of target genes in the presence of cofactors, whereas ZIC2 is also suspected to be a transcriptional regulator. These genes are expressed at early developmental stages in the embryonic nervous system, but are down-regulated in the adult. Although SOX2 mRNA can be detected in some adult tissues, ZIC2 is expressed only in brain and testis, and SOX1, SOX3, and SOX21 transcripts are not detectable in normal adult tissues. Of SCLC cell lines tested, 80% expressed ZIC2 mRNA, and SOX1, SOX2, and SOX3 expression was detected in 40%, 50%, and 10%, respectively. SOX group B and ZIC2 antigens elicited serological responses in 30-40% of SCLC patients in this series, at titers up to 1:10(6). In sera from 23 normal adults, no antibody was detected against SOX group B or ZIC2 proteins except for one individual with low-titer anti-SOX2 antibody. Seroreactivity against SOX1 and 2 was consistently higher titered than SOX3 and 21 reactivity, suggesting SOX1 and/or SOX2 as the main antigens eliciting anti-SOX responses. Although paraneoplastic neurological syndromes have been associated with several SCLC antigens, neurological symptoms have not been observed in patients with anti-SOX or anti-ZIC2 antibodies.

CT10: a new cancer-testis (CT) antigen homologous to CT7 and the MAGE family, identified by representational-difference analysis.

Assays relying on humoral or T-cell-based recognition of tumor antigens to identify potential targets for immunotherapy have led to the discovery of a significant number of immunogenic gene products, including cancer-testis (CT) antigens predominantly expressed in cancer cells and male germ cells. The search for cancer-specific antigens has been extended via the technique of representational-difference analysis and SK-MEL-37, a melanoma cell line expressing a broad range of CT antigens. Using this approach, we have isolated CT antigen genes, genes over-expressed in cancer, e. g., PRAME and KOC, and genes encoding neuro-ectodermal markers. The identified CT antigen genes include the previously defined MAGE-A6, MAGE-A4a, MAGE-A10, CT7/MAGE-C1, as well as a novel gene designated CT10, which shows strong homology to CT7/MAGE-C1 both at cDNA and at genomic levels. Chromosome mapping localized CT10 to Xq27, in close proximity to CT7/MAGE-C1 and MAGE-A genes. CT10 mRNA is expressed in testis and in 20 to 30% of various human cancers. A serological survey identified 2 melanoma patients with anti-CT10 antibody, demonstrating the immunogenicity of CT10 in humans.

Expression of cancer-testis antigens in lung cancer: definition of bromodomain testis-specific gene (BRDT) as a new CT gene, CT9.

In an effort to define new cancer-testis (CT) genes, we investigated whether BRDT, a testis-restricted member of the RING3 family of transcriptional regulators, is also expressed in cancer. Standard RT-PCR expression analysis detected BRDT transcripts in 12 of 47 cases of non-small cell lung cancer and single cases of both squamous cell carcinoma of the head and neck (1/12) and esophagus (1/12) but not in melanoma or in cancers of the colon, breast, kidney and bladder. Typing of 33 non-small cell lung cancers for coexpression of a panel of CT antigens revealed a high incidence (60%) of MAGE-3 mRNA expression, followed by MAGE-1 (36%), CT7/MAGE-C1 (30%), CT10 (30%), SSX4 (23%), BRDT (21%), NY-ESO-1 (21%) and HOM-MEL-40/SSX2 (15%). The coexpression pattern of these antigens provides a foundation for developing a polyvalent lung cancer vaccine.

Lipid peroxidation and antioxidant enzyme levels of intestinal renal and muscle tissues after a 60 minutes exercise in trained mice.

To investigate the effect of blood perfusion difference on oxidant status, mice were trained by a 7-week running program. Two days after the last training session, mice were exercised for 60 minutes at the same training intensity. Changes in the concentration of thiobarbituric acid reactive substance (TBARS), as an index of lipid peroxidation, in intestine, kidney and muscle, were studied in trained mice immediately (0 h), 3 h and 24 h after the running exercise and in unexercised control group. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and xanthine oxidase (XO) were determined in these tissues. Tissue SOD activities were unaffected by the exercise. Muscle GPx activity increased after exercise (0 h and 3 h group, P < 0.01) and returned to control levels at 24 h, but there was not any significant difference in intestinal and renal tissues. Renal tissue XO activity could not be determined. There was not any significant difference among groups in intestinal tissue XO activity. The activity of XO was decreased only in skeletal muscle at 0 h (P < 0.05). TBARS levels of exercised groups were higher than control in muscle (P < 0.01). Intestinal TBARS levels decreased at 0 h (P < 0.05), than reached to control level. Renal TBARS levels of 0 h and 24 h group was higher than control (P < 0.01, P < 0.01 respectively). The results show that a long distance running exercise may cause lipid peroxidation damage in skeletal muscle and kidney.

The effect of skin transplantation on tumor growth in mice.

BACKGROUND: Skin allograft is an immunostimulant. Skin allograft activates effector arms of the immune system including the cytotoxic T lymphocytes, activated macrophages, and natural killer cells. These cells may be involved in the destruction of tumor cells. METHODS: Balb/c mice were divided into the study (n = 10) and control (n = 10) groups. Alloskin grafts 1 cm in diameter from the backs of Swiss albino mice were placed on the backs of balb/c mice (study group). The same size autoskin grafts from the backs of other balb/c mice were used for the control group. Fourteen days after grafting, we inoculated 1,000 Ehrlich ascites tumor cells intraperitoneally into both groups. Two days after tumor inoculation, we used secondary allografts and autografts (which were about 2 to 3 mm in diameter) for the same groups. We followed up graft survival and animal survival in both groups. RESULTS: All 10 of the autografted mice died between the 18th and 25th days owing to malignancy. In the allografted group, 2 mice died (1 on day 17 and the other on day 23). Allograft rejection had not occurred in these 2 mice at the time of their death. The other 8 mice in the same group rejected allograft, on average within 9 days (9+/-3, median 8). These 8 mice were alive and without apparent health problems during the 4 months of follow-up. CONCLUSION: Allo-skin graft rejection may help rejection of tumor cells and may be of use in immunotherapy of cancer.

Antigens recognized by autologous antibody in patients with renal-cell carcinoma.

The screening of cDNA expression libraries derived from human tumors with autologous antibody (SEREX) is a powerful method for defining the structure of tumor antigens recognized by the humoral immune system. Sixty-five distinct antigens (NY-REN-1 to NY-REN-65) reactive with autologous IgG were identified by SEREX analysis of 4 renal cancer patients and were characterized in terms of cDNA sequence, mRNA expression pattern, and reactivity with allogeneic sera. REN-9, -10, -19, and -26 have a known association with human cancer. REN-9 (LUCA-15) and REN-10 (gene 21) map to the small cell lung cancer tumor suppressor gene locus on chromosome 3p21.3. REN-19 is equivalent to LKB1/STK11, a gene that is defective in Peutz-Jeghers syndrome and cancer. REN-26 is encoded by the bcr gene involved in the [t(9:22)] bcr/abl translocation. Genes encoding 3 of the antigens in the series showed differential mRNA expression; REN-3 displays a pattern of tissue-specific isoforms, and REN-21 and REN-43 are expressed at a high level in testis in comparison to 15 other normal tissues. The other 62 antigens were broadly expressed in normal tissues. With regard to immunogenicity, 20 of the 65 antigens reacted only with autologous sera. Thirty-three antigens reacted with sera from normal donors, indicating that their immunogenicity is not restricted to cancer. The remaining 12 antigens reacted with sera from 5-25% of the cancer patients but not with sera from normal donors. Seventy percent of the renal cancer patients had antibodies directed against one or more of these 12 antigens. Our results demonstrate the potential of the SEREX approach for the analysis of the humoral immune response against human cancer.

The role of vitamin A in preventing renal scarring secondary to pyelonephritis.

OBJECTIVE: To evaluate the efficiency of exogenously administered vitamin A in preventing renal scarring caused by experimental pyelonephritis in rats. MATERIALS AND METHODS: Forty Wistar rats were injected with 0.1 mL of solution containing Escherichia coli (1010 /mL) into both renal medullae. Five equal groups were then formed: group 1 was treated only with ciprofloxacin (30 mg/kg per day, twice daily, intraperitoneally) for 5 days, starting 3 days after bacterial inoculation; in group 2, 60 kIU of vitamin A was injected intramuscularly with the bacterial inoculation; in group 3, 60 kIU of vitamin A was injected similarly, but 3 days after bacterial inoculation; in group 4, 60 kIU of vitamin A was given orally with the bacterial inoculation; and group 5 was treated with ciprofloxacin for 5 days and vitamin A intramuscularly from the third day after bacterial inoculation. All the rats were killed 6 weeks after bacterial injection; blood samples were obtained to determine serum vitamin A and beta-carotene levels, and both kidneys were examined pathologically for scarring, graded as 0 (none), 1 (mild), 2 (moderate) and 3 (severe). RESULTS: Serum vitamin A levels were higher in the rats given vitamin A (group 2-5) than in group 1, being highest in group 4, although only this group had significantly higher levels of vitamin A than group 1 (P<0.05). Histopathologically, the fibrosis was mildest in groups 2 and 4 (two of 16 kidneys grade 1), whereas it was most severe in group 1 (all 16 grade 2-3). Fibrosis was significantly less in groups 2-5 than in group 1 (P<0.05). There was a significant negative correlation between vitamin A levels and the sum of the fibrosis, inflammation and tubular atrophy scores of all rats (r=-0.391, P<0.02). beta-carotene levels were unrelated to renal scarring. CONCLUSION: The administration of vitamin A could have a role in preventing renal scar formation from pyelonephritis induced experimentally in rats.

Isoforms of the human PDZ-73 protein exhibit differential tissue expression.

Patients with renal and colon cancer frequently develop IgG autoantibodies toward the NY-CO-38/PDZ-73 antigen, a protein of 652 amino acids (73 kDa) which contains three copies of the PDZ protein-protein interaction domain. The gene encoding PDZ-73 mapped to chromosome 11p15.4-p15.1. Additional tissue-specific isoforms were identified: PDZ-45, which lacks the third PDZ domain and the putative PEST protein degradation motif, is expressed in kidney, colon, small intestine, brain and testis; PDZ-54 and PDZ-59, which also lack the third PDZ domains, have unique carboxyl terminal amino acids and are expressed in brain, kidney, bladder, colon cancer and renal cancer; and a putative PDZ-37 isoform, containing only the third PDZ domain, that is expressed in the central nervous system. Immunohistochemical staining with anti-PDZ 73 monoclonal antibodies showed strong cytoplasmic reactivity in epithelial cells of the small intestine, colon and kidney tubules, with a prominent apical staining pattern in cells of the small intestine. The reactivity pattern of the antibodies with various tissues correlated with the mRNA expression pattern of the PDZ-45 isoform. The existence of multiple PDZ-73 isoforms with variations in tissue distribution, PDZ domains, protein degradation sequences and carboxyl terminal structure indicate that these isoforms have distinct tissue-specific functions.