Resveratrol Promotes Autophagy to Improve neuronal Injury in Parkinson's Disease by Regulating SNHG1/miR-128-3p/SNCA Axis

BACKGROUND

Parkinson's disease (PD) is seriously threatening the health and life quality of the elderly, who have a high incidence and high disability rate. Resveratrol (RES) was reported to play a protective role in PD. However, the functions and potential mechanism of RES in PD remain unclear, which need to be further explored.

METHODS

Human neuroblastoma cells (SH-SY5Y and SK-N-SH) were subjected to 1-Methyl-4-phenylpyridium (MPP+) induction to construct a cell model of PD. Cell viability was evaluated using CCK-8. The gene expression was evaluated using qRT-PCR and western blot. Luciferase activity assay and RIP were performed to validate interactions among SNHG1, miR-128-3p and SNCA.

RESULTS

Our results exhibited that RES reduced SNHG1 and SNCA expression but elevated miR-128-3p expression in human neuroblastoma cells upon MPP+ induction. Functionally, RES resulted in the promotion of cell autophagy in MPP+-induced human neuroblastoma cells, while these influences were abolished by SNHG1 overexpression. Mechanistically, SNHG1 could indirectly elevate SNCA expression via sponging miR-128-3p. Moreover, SNCA overexpression reversed SNHG1 silencing-induced cell autophagy in MPP+-induced human neuroblastoma cells upon RES pre-incubation.

CONCLUSIONS

RES prevented MPP+-induced repression of cell autophagy through inhibiting the SNHG1/miR-128-3p/SNCA axis, suggesting that RES might play a preventive effect on PD progression.

Effect of ginkgolide B on brain metabolism and tissue oxygenation in severe haemorrhagic stroke

Ginkgolide B, a diterpene, is an herbal constituent isolated from the leaves of Ginkgo biloba tree. The present study demonstrates the effect of ginkgolide B in osmotherapy on brain metabolism and tissue oxygenation. Multimodality monitoring including intracranial pressure (ICP), cerebral perfusion pressure (CPP), partial pressure of brain tissue oxygen (PbtO2), lactate/pyruvate ratio (LPR) and microdialysis were employed to study the effect of ginkgolide B osmotherapy. The results demonstrated that administration of 15% solution of ginkgolide B to the comatose patients with raised ICP (> 20 mm Hg) and resistant to standard therapy led to a significant decrease in ICP. The cerebral microdialysis was used to compare mean arterial blood pressure (MAP), ICP, CPP, PbtO2, brain lactate, pyruvate and glucose level after hourly intervals starting 3 h before and up to 4 h after hyperosmolar therapy. There was a decrease in ICP in 45 min from 23 ± 14 mm Hg (P < 0.001) to 18 ± 24 mm Hg and increase in CPP after 1 h of gingkolide B infusion from 74 ± 18 to 85 ± 22 mm Hg (P < 0.002). However there was no significant effect on MAP but PbtO2 was maintained in the range of 22-26. The peak lactate/pyruvate ratio was recorded at the time of initiation of osmotherapy (44 ± 20) with an 18% decrease over 2 h following gingkolide B therapy. Also the brain glucose remained unaffected.

[Changes in plasma content of matrix metallo proteinase-9 in acute cerebral infarction patients before and after thrombolytic therapy and its significance]

OBJECTIVE

To investigate the changes in the content of plasma matrix metallo proteinase-9 (MMP-9) in patients with acute cerebral infarction before and after thrombolytic therapy and its clinical significance.

METHODS

The levels of MMP-9 were determined in 34 patients with acute cerebral infarction before and after thrombolytic therapy, and 34 healthy individuals served as healthy control.

RESULTS

Compared with the healthy controls, the levels of plasma MMP-9 before thrombolytic therapy were not significantly increased [(13.47±3.09) ng/L vs. (12.89±10.22) ng/L, P >0.05]. In contrast, MMP-9 values were significantly increased after thrombolytic therapy [(22.06±12.53) ng/L] compared with that in either before or healthy control group (both P<0.05). MMP-9 values were significantly higher in patients with hemorrhage after thrombolytic therapy (incidence rate was 26.5%, 9/34) compared with before treatment [(24.02±15.41) ng/L vs. (14.28±2.33) ng/L, P<0.05], and the values of MMP-9 were higher than those of patients without hemorrhage [(20.42±9.57) ng/L], but there was no statistically significant difference ( P >0.05). In patients with complete revascularization (revascularization rate was 58.8%, 20/34), MMP-9 level was markedly higher than before thrombolytic therapy after thrombolytic therapy [(19.26±7.94) ng/L vs. (13.63±3.02) ng/L, P<0.05], and the values of MMP-9 were higher than the no-revascularization patients [(18.97±4.23) ng/L], but there was no statistically significant difference ( P >0.05).

CONCLUSION

Thrombolytic therapy activated MMP-9, and MMP-9 increased the risk of hemorrhage after thrombolytic therapy, and it participated in the mechanisms of hemorrhagic tendency after thrombolysis.

Helicobacter pylori (H. pylori) molecular signature in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma

Conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal marginal zone B-cell lymphoma that is characterized by an exaggerated clonal expansion of B cells, which implicate a pathological proliferative response to antigen(s) including bacteria. Helicobacter pylori (H. pylori) infection is recognized as one of the causative agents of gastric MALT lymphoma; however, it has not been reported in extra gastric MALT lymphoma. We studied 5 patients (4 adults and 1 child) with salmon-colored conjunctival lesions. One patient also had a history of abnormal bone marrow biopsy a year earlier with lymphoid aggregates involving 5% of the overall bone marrow. The conjunctival lesions of the 5 patients were biopsied. Histopathological diagnoses were consistent with conjunctival MALT lymphoma. Lymphoma and normal conjunctival cells were microdissected using laser capture microscopy or manual techniques. DNA was extracted and subjected to PCR amplification using H. pylori gene-specific primers from the urease B and vac/m2 gene. Cells from chronic conjunctivitis (normal lymphocytes), conjunctival human T-cell lymphotropic virus type-1/adult T-cell leukemia/lymphoma (HTLV-1/ATL), and orbital B-cell lymphoma were also microdissected, processed and analyzed. PCR amplification and Southern blot hybridization demonstrated H. pylori DNA in the conjunctival MALT lymphoma cells of 4/5 cases. The negative case was the one with a history of abnormal bone marrow. In contrast, H. pylori gene was not detected in normal conjunctival cells from the cases of MALT lymphoma or the lymphocytes, ATL and orbital B-lymphoma cells from the controls. These data suggest that H. pylori may play a role in conjunctival MALT lymphoma.

The role of apoptosis in the pathogenesis of Fuchs endothelial dystrophy of the cornea

OBJECTIVE

To investigate the potential role of apoptosis in the pathogenesis of Fuchs endothelial dystrophy of the cornea.

METHODS

Twenty-one corneal buttons from patients with Fuchs dystrophy and 15 control corneas were studied. Apoptosis was assessed by the in situ end-labeling of double-stranded DNA breaks, and by immunohistochemical characterization of cellular markers associated with apoptosis (Fas, FasL, Bcl-2, and Bax). Expression of Bcl-2 and Bax mRNA in the corneal stroma and endothelium was separately analyzed by a semiquantitative reverse transcriptase polymerase chain reaction. Furthermore, cultivated keratocytes generated from diseased corneal buttons and donor rims were exposed to camptothecin, an apoptotic inducer, for 6 and 24 hours. They were then examined for protein and messenger RNA (mRNA) expression of apoptotic regulatory molecules.

RESULTS

DNA fragmentation was seen in the epithelium, stroma, and endothelium in 6 of 7 corneas with Fuchs dystrophy. A statistically significant difference was identified in the expression of Bax and its mRNA in the stroma, but not in the endothelium of Fuchs dystrophy corneas. Following exposure to camptothecin, keratocytes from patients with Fuchs dystrophy responded with an increased level of Bax and a low level of Bcl-2. This trend was distinctively different from the response of normal keratocytes.

CONCLUSIONS

The evidence in this study points to a disease-related disturbance in the regulation of apoptosis in Fuchs dystrophy. Our findings suggest that excessive apoptosis may be an important mechanism in the pathogenesis of Fuchs dystrophy.

Detection of Toxoplasma gondii DNA in primary intraocular B-cell lymphoma

Primary intraocular lymphoma, a variant of primary central nervous system lymphoma with ocular involvement, is a large B-cell non-Hodgkin's lymphoma. Some cases of primary intraocular lymphoma have been reported to be associated with microorganisms including Epstein-Barr virus (EBV) and human herpes virus-8 (HHV-8), but not parasites. We analyzed 10 cases of primary intraocular lymphoma using microdissection and PCR. Tumor and normal cells were microdissected from ocular tissue on slides and subjected to PCR for genes from Toxoplasma gondii, EBV, and HHV-8. We detected Toxoplasma gondii, not HHV-8 or EBV, DNA in the lymphoma but not in normal cells of two cases that resembled ocular toxoplasmosis clinically. We speculate that Toxoplasma gondii may play a role in some forms of primary intraocular B-cell lymphoma.

Involvement of apoptosis and interferon-gamma in murine toxoplasmosis

PURPOSE

A murine toxoplasmosis model has been developed that results in central nervous system (CNS) and ocular inflammation characterized by encephalitis with numerous brain tissue cysts and milder inflammation with rare tissue cysts in the eye after 4 weeks of Toxoplasma gondii infection. In this model IFN gamma and inducible nitric oxide (iNO) are protective against T. gondii infection. In this study, the role of apoptosis in the pathogenesis of toxoplasmosis was investigated.

METHODS

C57BL/6 (wild-type mice), B6MRL/lpr, and B6MRL/gld (defective Fas or FasL expression, respectively) mice were infected intraperitoneally with 20 to 30 tissue cysts of the ME-49 strain of T. gondii. Mice were killed at days 0, 14, or 28 after infection. The eyes and brains were harvested for histologic, immunohistochemical, and molecular studies. Analysis included immunostaining for Fas, FasL, Bcl-2, and Bax; in situ apoptosis detection (TUNEL assay); RT-PCR amplification for IFN gamma; and measurement of ocular nitrite levels. The control mice were naïve mice of each strain that received no inoculation or injection.

RESULTS

Wild-type mice appeared to constitutively express apoptotic molecules at higher levels in the eye than in the brain. Consequently, during T. gondii infection, apoptosis was greater in the eyes than in the brain. Untreated naïve lpr and gld mice showed no expression of Fas and FasL, respectively. After infection, a slightly higher number of tissue cysts (lpr, 11.8 +/- 2.4; gld, 10.3 +/- 3.4) were found in the brains of the mutants than in the control animals (8.8 +/- 2.9). However, no significant differences between the number of apoptotic cells, inflammatory scores, or number of tissue cysts were noted in the eyes. IFN gamma mRNA in control mice was detected at day 28 after infection, whereas in both mutants, mRNA production occurred earlier, at day 14. Ocular nitrite levels were higher in lpr and gld mice than in wild-type mice.

CONCLUSIONS

No significant difference in the degree of ocular inflammation and apoptosis was detected between the wild-type and Fas or FasL mutant mice. However, there was an earlier and subjectively greater expression of IFN gamma in the brain and eye and a higher level of nitrite in the ocular tissue of mutant strains than in the wild type. Multiple factors are likely to be involved in the pathogenesis of ocular toxoplasmosis.

Therapeutic applications of antiflammin peptides in experimental ocular inflammation

Antiflammins are synthetic peptides derived from the region of highest local similarity between uteroglobulin and lipocortin. These peptides have shown anti-inflammatory activity on carrageenan-induced rat footpad edema. They are potent inhibitors for phospholipase A2 activation both in vitro and in vivo. Previously, we have demonstrated the effectiveness of topical antiflammins in suppressing acute ocular inflammation and allergic response in rodent endotoxin-induced uveitis and murine allergic conjunctivitis. The mechanisms by which antiflammins protect against inflammation and allergy in these ocular models may involve inhibition of phospholipase A2 and inducible nitric oxide synthase (iNOS) as well as the production of proinflammatory cytokine, interleukin-6.

Signal transduction and biochemical targeting of ovarian carcinoma

The purpose was to identify novel targets for the chemotherapy of ovarian carcinoma.

METHODS

Assays were worked out to measure the activities of P1 kinase, PIP kinase and PLC in ovarian carcinoma samples and in OVCAR-5 cells and to compare the activities to those in normal ovaries. A method was also designed for measuring the concentration of the end product of signal transduction, IP3.

RESULTS AND DISCUSSION

Signal transduction activity was markedly increased in ovarian cancer cells as shown by the increased steady-state activities of the three enzymes and the elevated concentrations of IP3. Inhibitors blocked activities of PI kinase (quercetin), PIP kinase (genistein), and lowered GTP concentration required for PLC (tiazofurin). Combinations of tiazofurin with quercetin, tiazofurin with genistein, and quercetin with genistein yielded a synergistic kill of ovarian cancer cells. Tiazofurin, quercetin and genistein are in various stages of clinical trials.

CONCLUSION

The increased signal transduction activity provides novel, sensitive targets to chemotherapy in ovarian cancer cells.

Cytokine gene expression in different strains of mice with endotoxin-induced uveitis (EIU)

PURPOSE

The kinetics of various cytokines in the eye plays a critical role in endotoxin-induced uveitis (EIU). This study examined the cytokine kinetics and susceptibility of EIU in four mice strains.

METHODS

Four strains of TLR-4 or Toll-like receptor-4 (Lps, lipopolysaccharide-susceptible) gene-positive mice (C3H/HeN of H-2(k), C57/B6 of H-2(b), Balb/C of H-2(d), and 129/J of H-2(b)) were injected subcutaneously with either lipopolysaccharide (LPS) in phosphate-buffered saline (PBS) or PBS alone in two repeated experiments. Mice were sacrificed 1, 3, 6, 24 (1 d), 72 (3 d), 120 (5 d), or 168 (7 d) hours after LPS injection. Ocular histology and reverse transcriptase-polymerase chain reaction (RT-PCR) to detect ocular interleukin-1 alpha (IL-1 alpha), IL-6, tumor necrosis factor-alpha (TNF-alpha), and granulocyte-macrophage colony-stimulating factor (GM-CSF) mRNA were performed. Serum IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha levels were measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

No ocular inflammation was present in any mice within six hours after LPS injection. Only the C3H/HeN mice developed a biphasic ocular inflammatory response (1 d and 5 d), during which all proinflammatory cytokine messages were expressed. In the other three strains with minimal (129/J and Balb/C) to mild (C57/B6) EIU that peaked at 1 d, IL-6 mRNA was barely detectable in C57/B6 and Balb/C; GM-CSF mRNA was also present in C57/B6. Serum IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha were high in all EIU mice within six hours after LPS injection. Control mice did not develop uveitis or measurable cytokine messages.

CONCLUSION

In the most susceptible strain, C3H/HeN, EIU was biphasic and correlated to multiple proinflammatory cytokines released in the eye. The less susceptible mice strains exhibited a monophasic response to LPS that may result from no cytokine cascade.

Biphasic ocular inflammatory response to endotoxin-induced uveitis in the mouse

OBJECTIVE

To examine the kinetics and mechanisms of endotoxin-induced uveitis in the mouse.

METHODS

C3H/HeN mice were injected subcutaneously with 0.3 mg of Salmonella typhimurium lipopolysaccharide (LPS) in 0.1 mL of phosphate-buffered saline solution or phosphate-buffered saline solution alone in 3 separate experiments; mice were killed after 1, 3, 5, and 7 days. In 2 other separate experiments, mice were killed 1, 3, 6, and 24 hours after LPS injection. All eyes were collected for histological examination, immunohistochemical analyses, aqueous protein level determination, and reverse transcriptase-polymerase chain reaction for ocular interleukin (IL)1alpha, IL-6, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor messenger RNA (mRNA). Enzyme-linked immunosorbent assay was used to measure tumor necrosis factor alpha and IL-6 levels in aqueous and serum samples.

RESULTS

Results were consistent for all experiments. Numbers of ocular inflammatory cells and levels of aqueous protein peaked 1 and 5 days after LPS injection. Control mice did not develop inflammation. Serum and aqueous IL-6 and ocular IL-6 mRNA levels peaked at 1 day and subsided at 3 days. However, ocular IL-1alpha, tumor necrosis factor alpha, and granulocyte-macrophage colony-stimulating factor mRNA appeared, peaked, and subsided at 3, 5, and 7 days, respectively. Predominant infiltrating cells were neutrophils at 1 day and macrophages at 5 days. Although no ocular inflammatory cells were detected before 24 hours after LPS injection, tumor necrosis factor alpha mRNA was noticed at 1 hour, peaked at 3 hours, and disappeared at 6 hours and granulocyte-macrophage colony-stimulating factor mRNA was spotted only at 3 hours after LPS injection.

CONCLUSIONS

The ocular inflammatory response to C3H/ HeN mouse endotoxin-induced uveitis is biphasic for 7 days. The first wave appears at day 1 and subsides by day 3. A second, higher peak appears at day 5. The 2 inflammatory waves are related to the kinetics of the different cytokines released in the eye. This is in contrast to the rat monophasic endotoxin-induced uveitis model, which has only one peak of intense inflammation associated with cytokine release.

CLINICAL RELEVANCE

A biphasic inflammatory response associated with cytokine release lasting several days is observed in C3H/HeN mice with endotoxin-induced uveitis. Because human anterior uveitis has a tendency to be recurrent in nature, this might be a better experimental model.

Rearrangement of immunoglobulin gene in metastatic Waldenström macroglobulinemia to the vitreous

PURPOSE

To report metastatic Waldenström macroglobulinemia cells with immunoglobulin heavy chain gene rearrangement in the vitreous and the blood.

METHODS

A 58-year-old man with Waldenström macroglobulinemia developed bilateral vitreitis. Diagnostic vitrectomy was performed on the left eye. The vitreous cells and the peripheral blood lymphocytes were analyzed using microdissection and polymerase chain reaction amplification.

RESULTS

Vitrectomy specimen of the left eye contained a few degenerated cells. Molecular analysis showed immunoglobulin heavy chain gene rearrangement at the third complementary determining region of the vitreal infiltrating cells and peripheral blood lymphocytes.

CONCLUSIONS

Waldenström macroglobulinemia rarely metastasizes to the vitreous. Molecular detection of the immunoglobulin heavy chain gene third complementary determining region rearrangement is helpful in the diagnosis of the malignancy. Microdissection combined with polymerase chain reaction is a useful and innovative tool for molecular pathological investigation.

Fast and memory efficient implementation of the exact PNN

Straightforward implementation of the exact pairwise nearest neighbor (PNN) algorithm takes O(N3) time, where N is the number of training vectors. This is rather slow in practical situations. Fortunately, much faster implementation can be obtained with rather simple modifications to the basic algorithm. In this paper, we propose a fast O(tauN2) time implementation of the exact PNN, where tau is shown to be significantly smaller than N, We give all necessary data structures and implementation details, and give the time complexity of the algorithm both in the best case and in the worst case. The proposed implementation achieves the results of the exact PNN with the same O(N) memory requirement.

Inhibition of experimental melanin protein-induced uveitis (EMIU) by targeting nitric oxide via phosphatidylcholine-specific phospholipase C

Experimental melanin protein-induced uveitis (EMIU) is an autoimmune uveitis induced by immunization with uveal melanin protein. Fas and FasL enhancement is reported in rats with EMIU. Tricyclodecan-9-yl-xanthogenate (D609), a specific inhibitor of phosphatidylcholine-specific phospholipase C, inhibits inducible nitric oxide synthase (iNOS) induction. In two independent experiments, 35 Lewis rats with EMIU received either D609 or PBS daily. The eyes and draining lymph nodes were collected for histology, analyses of nitrite, peroxide, and superoxide dismutase, Fas and FasL immunochemistry, in situ hybridization for iNOS mRNA and in situ apoptosis detection at the peak of the disease. Both experiments showed significant inhibition of EMIU by D609. Decreases in nitrite and peroxide, increase of superoxide dismutase and lower expressions of iNOS mRNA were found in D609-treated, as compared to PBS-treated eyes. There was mild enhancement of Fas and FasL in the eyes and lymph nodes of D609-injected animals. DNA fragmentation was increased in the lymph nodes of D609-treated rats. We conclude that iNOS activation is responsible for NO production in eyes with EMIU. The suppressive effect of D609 on EMIU may result from scavenging NO and activating apoptosis previously inhibited by NO along with other anti-inflammatory effects.

Morphologic and genetic analysis of retinal angioma associated with massive gliosis in a patient with von Hippel-Lindau disease

We report morphologic and genetic analysis of bilateral retinal angiomas in a 35-year-old patient with von Hippel-Lindau (VHL) disease. Enucleation of both eyes revealed extensive intraocular tumor. Whereas the right eye demonstrated large amounts of retinal angioma tissue, the left eye showed small areas of retinal angioma associated with massive diffuse retinal gliosis. Genetic analysis of the angioma showed allelic deletion of the VHL gene locus, suggesting that the origin of the angiomas was directly related to the patient's underlying VHL disease. Genetic analysis of the pleomorphic glial proliferation showed no allelic VHL gene deletion, which is consistent with the assessment that the glial component represents a reactive process. Apoptosis detected by TUNEL revealed lack of DNA fragmentation in the angioma; in contrast, many positive signals were found in the massive gliosis. We confirmed that the abnormal VHL genes were located in the "stromal" cells of the retinal angioma. Massive gliosis in VHL disease is a true reactive retinal gliosis.

VHL gene deletion and enhanced VEGF gene expression detected in the stromal cells of retinal angioma

OBJECTIVE

Retinal angioma frequently occurs in von Hippel-Lindau (VHL) disease. However, VHL gene alterations have not been documented in retinal angiomas.

METHODS

Using tissue microdissection and polymerase chain reaction amplification, we have analyzed 7 retinal angiomas associated with VHL disease for loss of heterozygosity of the VHL gene. In addition, vascular endothelial growth factor expression was evaluated in these tumors by immunohistochemistry and in situ hybridization.

RESULTS

All 6 informative retinal angiomas showed loss of heterozygosity of the VHL gene. Loss of heterozygosity was detected in vacuolated "stromal" cells, but not in vascular cells or reactive glial tissue. Vascular endothelial growth factor protein and messenger RNA were also present in vacuolated "stromal" cells.

CONCLUSIONS

These findings suggest that vacuolated "stromal" cells represent the true neoplastic component in retinal angioma. These cells express vascular endothelial growth factor and therefore may be responsible for abundant neovascularization of retinal angioma.

Utility of microdissection and polymerase chain reaction for the detection of immunoglobulin gene rearrangement and translocation in primary intraocular lymphoma

OBJECTIVE

Primary intraocular lymphoma, a non-Hodgkin's lymphoma, is a primary central nervous system lymphoma (PCNSL). Diagnosis is usually made by identifying malignant, large B lymphocytes in the vitreous, eye, brain, and cerebral spinal fluid; however, these cells are few, friable, and difficult to recognize. Recently, clonal heavy chain immunoglobulin (IgH) gene rearrangement and bcl-2 gene translocation have been reported in systemic B-cell lymphoma and are used for the detection of malignant cells and in making a diagnosis. The authors investigated the molecular changes in three eyes and a chorioretinal biopsy specimen of four patients with PCNSL.

DESIGN

Human tissue study.

MATERIALS

Five ocular specimens of PCNSL were collected.

INTERVENTION

The first patient had a diagnostic enucleation of the left eye. The second patient underwent diagnostic chorioretinal biopsy. In the third case, a pair of autopsied eyes with reactive lymphoplasmacytic infiltrates of a patient with acquired immune deficiency syndrome (AIDS) were studied. In the fourth case, an enucleated eye of a patient with AIDS-associated lymphoma was sampled.

MAIN OUTCOME MEASURES

The bcl-2 and IgH genes of the lymphoma cells from routine, paraffin-embedded, formaldehyde-fixed, or frozen histologic tissue sections were analyzed using microdissection and polymerase chain reaction (PCR) technique.

RESULTS

Lymphoma cells obtained from the above four cases showed IgH rearrangement gene in the third framework of the VH region. Bcl-2-associated translocation also was detected in three cases (cases 1, 2, and 4).

CONCLUSION

Rearrangement of the IgH gene can serve as a molecular marker for PCNSL. Microdissection allows for procurement and analysis of specific, selected, minute cell populations that are obtained from histologic sections of the complex, heterogeneous tissue. Translocation of IgH and bcl-2, the apoptotic "survival" signal and proto-oncogene, could contribute to the pathogenesis of PCNSL. The combination of microdissection and PCR is a powerful tool for studies of small lesions and cell populations and for understanding disease mechanisms.

High-resolution analysis of T-cell receptor beta-chain repertoires using DNA heteroduplex tracking: generally stable, clonal CD8+ expansions in all healthy young adults

The accurate measurement of T-cell receptor (TCR) repertoire changes requires the analysis of a representative sampling of complex T-cell populations. The number and frequency of clonally expanded TCR beta-chain transcripts bearing distinct CDR3 sequences were accurately determined using a simple DNA heteroduplex tracking assay. This method allowed major and minor clonal expansions (> or = 1% of a Vbeta subfamily's transcripts) to be rapidly and reproducibly quantified. Oligoclonal CD8 + cell expansions were detected in all young adults tested, while CD4 + cells generally expressed more polyclonal beta-chain repertoires. The same pattern of CD8 + cells oligoclonality and CD4 + cells polyclonality was observed in asymptomatic HIV-1 infected individuals with high CD4 + cell counts. CD8 + CD45RA + and CD8 + CD45RO + cell fractions both displayed oligoclonal, although distinct, TCR beta chain repertoires while CD8 + cells from umbilical cord blood were generally polyclonal. Oligoclonal CD8 + cell repertoires from young adults were generally stable over a period of weeks, although minor, transient, clonal expansions could also be detected in the absence of symptomatic infections. DNA heteroduplex tracking analysis provided a higher level of sensitivity for the detection of TCR beta chain transcript expansions than CDR3 length (spectrotyping/immunoscope) analysis. DNA heteroduplex tracking of TCR beta-chain transcripts is therefore a simple and sensitive method for assessing the level of clonality and for measuring changes in the TCR beta chain repertoire of different T-cell populations.

Recombinant adenovirus encoding gp100 modulates experimental melanin-protein induced uveitis (EMIU)

Experimental melanin-protein induced uveitis (EMIU) is a T-cell mediated autoimmune uveitis induced by immunization with bovine uveal melanin protein. Gp100, a melanocyte lineage-specific protein, is identified as a human melanoma antigen. A recombinant adenovirus construct encoding gp100 (Ad2CMV-gp100) has been used as a vaccine for cancer therapy. This study examines the effect of Ad2CMV-gp100 on EMIU. To induce EMIU, rats were injected intraperitoneally on day 7 before immunization with ad2CMV-gp100, control adenovirus encoding LacZ (Ad2CMV-LacZ), or no virus. On day 21 after immunization, the right eye was processed for histology and the left eye was analysed for cytokines by quantitative reverse transcriptase-polymerase chain reaction. Western blot analysis showed that uveal melanin-protein contains gp100. In three independent experiments, ocular inflammation was significantly suppressed, and expression of ocular IL-12p40 mRNA was much lower in the rats which received Ad2CMV-gp100 before immunization than in those that received Ad2CMV-LacZ or no virus. No abnormalities developed in rats which received Ad2CMV-gp100 or Ad2CMV-LacZ alone. Therefore, Ad2CMV-gp100 injection prevents the development of EMIU, at least in part, through cytokine regulation.

Isolation and characterization of a novel nucleic acid binding protein from calf lenses

The transitional process of lens cellular differentiation is accompanied by several unique morphological and biochemical changes. Pyknosis or apoptosis of the nucleus involves extensive degradation of genetic materials. In an attempt to search for a gene product responsible for such a regulatory process, we have adopted DNA-cellulose affinity chromatography to enrich the specific binding protein. A binding protein was isolated by high salt (0.8M KCl) wash of the lens polysomal fraction and purified to apparent homogeneity by DNA-cellulose affinity column and chromatofocusing. The nucleic acid binding protein has an apparent molecular weight of 36,000, designated as regulatory factor 36 (RF-36), as determined by SDS/PAGE. Amino acid composition analysis indicated that RF-36 contains high proportions of glycine, alanine, characteristic of the core heteronucleus RNP proteins. Comparative immunological studies with other DNA binding protein antigen (e.g. helix destabilizing protein) suggest the existence of some common overlapping determinant. However, when monoclonal anti-RF-36 was used as immunoprobe, no cross immunoactivity was detected between these homologous binding proteins, suggesting some antigenic diversity among these two nucleic acid binding proteins from different organisms.

An improved method for covalent attachment of antibody to liposomes

A rapid and simple method is described for the incorporation of monoclonal antibody coupled with palmitic acid into liposomes prepared by the reverse-phase evaporation method (Szoka, F. and Papahadjopoulos, D. (1978) Proc. Natl. Acad. Sci. U.S.A. 75, 4194-4198). Palmitoyl antibody in 0.15% deoxycholate is added to a liposome suspension after the majority of the organic solvent has been removed by evaporation. Efficient incorporation (over 80%) of palmitoyl antibody occurred without leakage of the encapsulated drug. Native, unmodified antibody did not incorporate under identical conditions. About 50% of the incorporated antibodies could be readily digested by protease, while most of an internal protein marker was not, suggesting that about half of the antibodies were exposed on the outer surfaces of liposomes. Target-specific binding of antibody-liposomes has also been demonstrated in vitro with the RDM-4 lymphoma cells. This method offers a rapid and highly efficient attachment of functional antibody molecules to liposomes with high capture efficiency of drugs, and therefore should be useful in target-specific delivery of drugs mediated by liposomes.