Melanoma-associated antigens as messenger RNA detection markers for melanoma.

Melanoma is heterogeneous for its biological properties and melanoma-associated antigens (MAAs). This diversity is partially observed in the expression of the MAAs involved with the melanin synthesis pathway. We therefore developed a sensitive multimarker reverse transcription-PCR plus Southern blot assay using five MAAs as molecular markers to detect primary and metastatic melanoma cells. Melanoma cell lines, melanocytes (cultured), primary and metastatic malignant melanoma tissues, and blood from patients with American Joint Committee on Cancer stage I-IV melanoma were assessed for tyrosinase, tyrosinase-related proteins 1 and 2, Pmel 17, and MART-1/Melan-A. All of the MAA mRNA markers were expressed in 100% of melanoma cell lines and cultured melanocytes, 74% of primary and metastatic tumors (excluding tumor-draining lymph nodes), 43% of tumor-involved lymph nodes, and 43% of patients' bloods. Hypomelanotic melanoma tissues expressed a lower frequency of individual mRNA markers. Overall, at least one mRNA marker was expressed in more than 86% of specimens assayed. Normal tissue specimens from patients and blood from normal volunteer donors were negative for MAA mRNA expression. The multimarker MAA reverse transcription-PCR plus Southern blot analysis was more reliable and sensitive than a single-molecular marker assay for the detection of melanoma cells. This molecular assay can also provide information on MAA mRNA expression of metastatic melanoma cells that may assist in monitoring the therapeutic efficacy of active specific immunotherapy toward specific MAA-bearing melanomas.

Detection of occult melanoma cells in blood with a multiple-marker polymerase chain reaction assay.

PURPOSE: The objective of the study was to develop a sensitive multimarker polymerase chain reaction (PCR) assay to detect circulating melanoma cells in patient blood. The rationale was that malignant melanoma is heterogeneous in regards to antigen expression. PATIENTS AND METHODS: A PCR assay that uses four melanoma-associated gene markers (tyrosinase, p97, MUC18, and MAGE-3) was developed. Sensitivity and specificity of the PCR assay for individual markers were assessed using 10 melanoma cell lines and peripheral-blood lymphocytes (PBL) from 39 normal volunteers as controls. The assay's sensitivity and specificity were improved using nested primers and Southern blot analysis. Patients (N = 119) with American Joint Committee on Cancer (AJCC) stages I to IV disease were evaluated for circulating melanoma cells using the four gene markers under optimal conditions. RESULTS: All melanoma-associated gene markers were expressed in at least 80% of the melanoma lines, whereas 37 of 39 normal PBL tested negative for all markers; the remaining two PBL were positive for MUC18. Using four markers in the PCR assay was significantly better than using tyrosinase alone. There was a significant correlation between the number of positive PCR markers, AJCC stage of disease, and progression of disease. In all AJCC stages, there were more PCR-positive patients with disease than without disease. CONCLUSION: A multimarker PCR assay is more reliable and sensitive than a single-marker assay for detection of melanoma cells in blood of patients. This assay can provide important insight into tumor progression kinetics without major surgical or conventional radiologic diagnostic procedures.

Hippocampal pyramidal cell disarray in schizophrenia as a bilateral phenomenon.

In a continuing quantitative study of hippocampal cell orientation in schizophrenic subjects and nonschizophrenic control subjects, a pattern of right hemispheric cell disorganization in schizophrenic subjects, as robust as that previously described in the left hemisphere, was shown. The study was based on tissue from 11 schizophrenic and seven approximately age-matched control subjects from a Veterans Administration Medical Center. Using a new measuring technique that proved complementary and superior to the method formerly used, we determined the axes of orientation for approximately 10,800 neurons. A significant difference in cell disorganization was found between schizophrenic and control subjects. From separate analyses of the interface zones among the various hippocampal cell sectors, this difference was found to be significant at the interfaces between cornu ammonis zones 1 and 2 and zones 2 and 3. Analysis of the pattern of disorganization numbers suggests a bimodal distribution in which the cell orientation values of one group of schizophrenic subjects overlap those of the nonschizophrenic control group, while the cell orientation values of a second group significantly exceed those of the control population. Although some recent studies have suggested that schizophrenia may be related exclusively to the left hemisphere, the results of this study indicate that schizophrenia-related structural changes involve the right hemisphere as well. Thus, schizophrenia may be a bilateral rather than unilateral disorder.

Assessment of messenger RNA of beta 1-->4-N-acetylgalactosaminyl-transferase as a molecular marker for metastatic melanoma.

Gangliosides GM2 [GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta 1-4Glc beta 1-1Cer] and GD2 [GalNAc beta 1-4(NeuAc alpha 2-8NeuAc alpha 2-3)Gal beta 1-4Glc beta 1-1Cer] are cell surface tumor-associated antigens and have been demonstrated to be important markers of human malignant melanoma progression. Expression of these glycolipid antigens on melanoma tissues can be assessed by immunohistochemistry or biochemical analysis. These methodologies, however, are not logistically practical or sensitive for testing metastatic melanoma cells in blood or in tissue biopsies. In the present study, we hypothesized that the enzyme involved in GM2 and GD2 synthesis, beta 1-->4-N-acetylgalactosaminyltransferase (beta 1-->4GalNac-T), can be a useful marker for detection of occult metastatic melanoma. A reverse transcription PCR and Southern blot assay to detect beta 1-->4GalNac-T mRNA expression was developed. Beta 1-->4GalNac-T mRNA was detected in all 13 melanoma cell lines tested. Metastatic melanoma of lymph nodes and different organ sites expressed beta 1-->4GalNac-T mRNA at various levels. Detection sensitivity of the reverse transcription PCR assay was 1 ng of total RNA extracted from tumor specimens and approximately 5 melanoma cells in 20 million normal donor peripheral blood lymphocytes. In assessment of blood from 126 melanoma patients, beta 1-->4GalNac-T mRNA was more frequently found in advanced-stage melanomas and in patients showing more aggressive tumor progression. Normal donor blood samples (n = 37) were all negative for beta 1-->4GalNac-T mRNA expression. These results suggest that beta 1-->4GalNac-T mRNA is a promising molecular marker for detecting melanoma cells, characterizing antigen expression, and monitoring tumor progression.

Cerebrospinal fluid p24 antigen levels and intrathecal immunoglobulin G synthesis are associated with cognitive disease severity in HIV-1.

OBJECTIVE: To test the hypothesis that selected cerebrospinal fluid (CSF) markers [intrathecal immunoglobulin G (IgG) synthesis rate, oligoclonal IgG bands, and p24 antigen levels] are associated with the presence and severity of clinical HIV-1 neurologic disease. DESIGN AND METHODS: CSF and blood parameters from 142 HIV-seropositive subjects from the baseline examination of a longitudinal study were measured and analyzed in relationship with clinically derived cognitive impairment groups (none, mild, moderate) and with other neurologic and clinical classification groups. Subjects with opportunistic infections, lymphomas or neurosyphilis were excluded. RESULTS: The mean intrathecal IgG synthesis rate and mean CSF p24 antigen levels both differed significantly among cognitive impairment groups; more impairment was associated with a higher rate or level. Mean CSF p24 antigen levels were significantly higher in HIV-1-seropositive subjects with any HIV-1 neurologic disease than in subjects without neurologic disease. In contrast, there were no significant differences among seropositive groups in any CSF parameter when stratified by systemic disease classification (asymptomatic HIV-seropositives, AIDS-related complex, or AIDS), independent of neurologic status. CONCLUSION: We conclude that there may be a relationship between the severity of HIV cognitive disease and increasing levels of intrathecal IgG synthesis and CSF p24 antigen levels.

Herpes simplex virus in postmortem multiple sclerosis brain tissue.

BACKGROUND: Herpes simplex virus (HSV) is a common neurotropic virus that is capable of long latencies. It can cause focal demyelination in animals. OBJECTIVE: To test for the presence of HSV-1 and -2 in postmortem brain samples from patients with multiple sclerosis (MS) and controls using polymerase chain reaction and Southern blot hybridization. METHODS: Dissected plaque tissue classified as active or inactive and unaffected white matter (WM) and gray matter (GM) from 37 cases of MS were screened for HSV using polymerase chain reaction and Southern blot hybridization. White matter and GM from 22 cases of Alzheimer's disease, 17 cases of Parkinson's disease, and 22 cases without neurologic disease served as controls. RESULTS: Forty-six percent (17/37) of the MS cases and 28% (17/61) of the control cases had samples that were positive for HSV (P = .11). Forty-one percent (9/22) of active plaques and 20% (6/30) of inactive plaques were positive for HSV. Twenty-four percent (9/37) and 14% (5/37) of MS cases and 23% (14/61) and 13% (8/61) of non-MS cases had HSV in WM and GM, respectively. No significant differences were found among all subgroups (P = .10). CONCLUSIONS: Herpes simplex virus was present in more MS cases than control cases and in more active plaques than inactive plaques. The presence of HSV in WM and GM in cases of MS as well as in control cases makes an etiologic association to the MS disease process uncertain, but cellular localization of HSV and its relationship to oligodendrocytes and latency may reveal such an association in future studies.

Presence of herpes simplex DNA in surgical tissue from human epileptic seizure foci detected by polymerase chain reaction: preliminary study.

OBJECTIVES: To determine whether herpes simplex virus causes monofocal epilepsy and to assess the presence of herpes simplex virus 1 (HSV-1) and HSV-2 in surgical specimens from patients with epilepsy by using polymerase chain reaction and Southern blot analysis. BACKGROUND: Herpes simplex virus is a common neurotropic virus capable of latency within the central nervous system; it has a predilection for the temporal lobe. Central nervous system infection with HSV has been associated with seizure activity. DESIGN AND METHODS: Surgical specimens were removed from 50 patients as part of a treatment protocol for monofocal epilepsy. Neuropathological classification was done, and adjacent sections were screened for HSV by using polymerase chain reaction. Tissues obtained post mortem from the temporal lobe cortex of persons with Alzheimer disease (n=17), Parkinson disease (n=14), or nonneurological disease (n=17) served as controls. RESULTS: Twenty (40%) of the 50 epilepsy cases and 2 (4%) of the 48 control cases had at least one sample that tested positive for HSV (P<.001). Sixty-seven percent (8/12) of the epilepsy cases with heterotopia were positive for HSV. CONCLUSIONS: There was a statistically significant difference in the frequency of HSV-positive surgical specimens from monofocal seizure epicenters compared with nonepilepsy control specimens. These data suggest an association of the virus with seizure activity. All specimens positive for HSV (surgical specimens and control specimens) should be examined to determine the activity or latency state of the virus and cellular localization.

An analysis of acute changes in interleukin-6 levels after treatment of hepatitis C with consensus interferon.

Cytokine production has been implicated in the antiviral response to interferon-alpha (IFN-alpha) in hepatitis C and in the development of IFN-alpha-related side effects. We characterized acute changes in serum cytokine levels following administration of a single dose of consensus IFN (IFN-con1) and during continuous treatment of chronic hepatitis C patients. Serum samples were collected at baseline, at multiple times early after IFN administration, and weekly thereafter. Viral RNA titers were assessed by RT-PCR, and viral kinetics were followed. ELISA assays were used to measure IFN-gamma, tumor necrosis factor-alpha (TNF-alpha), interleukin-2 (IL-2), IL-4, IL-6, and IL-16. Serum cytokine levels were low at baseline. IL-6 was detected in patients with hepatitis C but not in healthy control subjects by either ELISA or RT-PCR, indicating that low levels of circulating IL-6 were associated with hepatitis C infection. None of the cytokines measured increased significantly after IFN administration except for IL-6. IL-6 levels rose rapidly, peaked at 6-15 h in a dose-dependent manner, and returned to baseline by 48 h in both patients receiving a single dose of IFN and those receiving continuous treatment. This was confirmed by RT-PCR. Pretreatment IL-6 levels were directly correlated with area under the curve (AUC) for IL-6 during the 24 h after IFN dosing (r = 0.611, p = 0.007). Viral titers decreased within 24-48 h after a single dose of IFN-con1. Changes in hepatitis C RNA titers were not significantly associated with pretreatment IL-6 levels or with changes in IL-6 levels. In conclusion, (1) baseline serum cytokine levels, except for IL-6, were low or within the normal range in patients with hepatitis C, (2) IL-6 levels were detected in some patients with hepatitis C before treatment but not in healthy controls, (3) IL-6 levels increased acutely after a single dose of IFN-alpha, and IL-6 induction was related to baseline IL-6 level, and (4) changes in IL-6 levels did not correlate with the early virologic response to IFN.

Detection of occult melanoma cells in sentinel lymph nodes and blood.

The presence or absence of regional nodal metastases is the most important prognostic factor for predicting survival in patients with clinical stage I or II cutaneous melanoma. Successful treatment of melanoma patients with primary tumors greater than 0.76-mm thick without clinically palpable nodes is thus critically dependent on identification and biopsy of the sentinel lymph nodes and the detection of possible occult micrometastases in those nodes. Biopsy of sentinel lymph nodes has been greatly facilitated by the development of lymphoscintigraphy. Immunohistochemical and polymerase chainreaction (PCR)-based detection of unique melanoma markers have also dramatically improved our ability to detect nodal micrometastases and assess the risk of recurrence in this patient population. These techniques now make it possible to perform complete lymph node dissection only in those patients with confirmed nodal metastases. The detection of occult melanoma cells in blood using a sensitive multimarker PCR assay is also contributing to the proper staging of melanoma. These techniques have greatly enhanced the oncologist's ability to make rational treatment decisions.

On classification of post-mortem multiple sclerosis plaques for neuroscientists.

Plaque classification is proposed based on observation of 348 plaques from 52 post-mortem multiple sclerosis (MS) cases. Four plaque types, ranging from 'earliest lesion' to 'inactive', are described according to immunological activation and degree of demyelination, seen by expression of the Major Histocompatibility Complex (MHC) Class II molecule, HLA-DR, and by Oil Red O staining, respectively. 40% of the plaques were inactive. This result highlights the need for a description of plaque activity for studies of the etiopathogenesis of MS; that is, the earliest and/or the most active plaques should contain the causative agent whereas the burnt out plaques should not.

Trans-blood-brain-barrier albumin leakage and comparisons of intrathecal IgG synthesis calculations in multiple sclerosis patients. Multiple Sclerosis Study Group, Alpha Interferon Study Group, and Azathioprine Study Group.

We compared four equations for estimating intrathecal IgG synthesis (Tibbling and Link IgG index (T/L), Schuller and Sagar (S/S), Reiber and Felgenhauer (R/F), and Tourtellotte (T) equations) using data from chronic progressive MS patients. For normal albumin leakage (AL) (< 75 mg/day-intact BBB), T (r = 0.15) and R/F (r = 0.10) showed comparable positive correlations with trans-BBB AL, T/L (r = -0.10) was negative and S/S was uncorrelated (r = 0.05). For abnormal AL (> or = 75 mg/day), the R/F (r = -0.24), S/S (r = -0.37) and the T/L (r = -0.22) equations overcorrected, whereas the T (r = 0.07) equation values did not correlate with AL. The albumin index and trans-BBB albumin leakage rate formulae gave essentially identical estimates of BBB leakage (r = 0.99, P = 0.0001). We conclude that in chronic progressive MS patients the R/F, T/L and S/S formulae overcompensate for large abnormal T-BBB albumin leakage rates. The T formula corrected best for IgG transudate at high AL rate values in MS.

Quantitation of intrathecal measles virus IgG antibody synthesis rate: subacute sclerosing panencephalitis and multiple sclerosis.

A method for quantitating specific anti-viral antibodies in serum and cerebrospinal fluid (CSF) is established using enzyme-linked immunosorbent assay (ELISA). Quantitated antibody levels are used to determine intrathecal specific IgG synthesis rate for the particular antibody. Measles virus was used as a model for validating this quantitative technique: a mutated form of measles virus is a cause of subacute sclerosing panencephalitis (SSPE) and there is a possibility that measles virus is related to the cause of multiple sclerosis (MS). Matched serum and CSF samples were assayed. Concentration of anti-measles IgG was determined and intrathecal measles-specific IgG synthesis rate was calculated. For the SSPE samples, measles-specific IgG synthesis rate was elevated and comprised > 20% of the total intrathecal IgG synthesis rate; these results are consistent with the literature. The ELISA method can be performed routinely, providing a quick, simple, reproducible means of quantitating specific antibody concentrations, with sensitivity greater than 1 nanogram per milliliter. With this method, quantitation of IgG antibodies to any other viral antigen can be reliably and precisely determined.

Histopathological features of hepatitis C in renal transplant candidates [see comment].

BACKGROUND: Although hepatitis C virus (HCV) infection is common in renal transplant candidates, its clinical significance remains unclear in this population. Little detailed information is available about the histological severity of HCV infection in these patients. We evaluated the liver biopsy features of chronic HCV in a large population of renal transplant candidates and investigated associations between histopathological changes and host- and virus-related factors. METHODS: Thirty-seven patients seropositive for anti-HCV with chronic renal failure (CRF) referred to UCLA Medical Center for kidney or kidney/liver transplantation during the period 1992-1997 were included. HCV genotype and viral load were measured. A multivariate analysis by logistic regression model was performed: age, gender, race, HCV load and genotype, CRF level, aspartate and alanine aminotransferase activity, duration of HCV infection, underlying nephropathy, and alcohol abuse were independent variables; liver histology score was assumed a dependent variable. RESULTS: Liver disease was present in all HCV-infected patients. Logistic regression analysis revealed that histological damage was (P = 0.0017) independently associated with the CRF level; the severity of liver disease, as shown by univariate analysis, being significantly higher in CRF patients not requiring dialysis than among dialysis population. All patients on dialysis showed mild or moderate necroinflammatory activity; the majority (22/28 = 79%) of these individuals had fibrosis, three (3/28 = 11%) dialysis patients had established cirrhosis. Thirty-one (84%) of 37 patients were tested by polymerase chain reaction, 25 (81%) patients had detectable HCV RNA in serum, the mean HCV load among viremic patients was 10.9x10(5) copies/ ml. The most frequent HCV genotypes were la (8/24 = 33%) and 1b (7/24 = 29%), followed by genotype 2b (3/24 = 12%). CONCLUSIONS: Pathological changes on liver biopsy were observed in all HCV-infected patients awaiting renal transplantation. The severity of histologic damage observed on liver biopsy was less in dialysis than predialysis CRF patients. All dialysis patients had mild or moderate necroinflammatory activity; fibrosis was frequent with 11% of them having cirrhosis. The HCV viral load was rather low; no relationship between liver histology changes and virological features of HCV or aminotransferase activity was apparent. Further studies with repeat liver biopsies after kidney transplantation to observe the evolution of HCV-related liver disease after immunosuppressive therapy are indicated. We suggest including liver biopsy in the evaluation of the HCV-infected renal transplant candidate.

Schizophrenia and the hippocampus: the embryological hypothesis extended.

Recent studies suggest that consistent structural changes exist in the hippocampi of schizophrenic patients. These alterations are characterized by a significant degree of disorientation of the hippocampal pyramidal cells when compared with age-matched nonschizophrenic controls. The degree of neuronal disorientation seems to correlate positively with the severity of the clinical picture. A hypothesis on the pathogenesis of this process, suggested in an earlier article, is extended here. Putative maternal infection with one of several neuraminidase-bearing viruses, especially during the second trimester of pregnancy, may severely affect the migration of primitive neurons into the primordial hippocampus. The "neuraminidase effect," expressed through alteration of the normal sequential patterns of N-CAM (neuronal-cell adhesion molecule) maturation, may result in the cellular disarray we have noted. This alteration may prove useful as a cell marker for schizophrenia, even though its actual relation to clinical symptomatology has still to be evaluated. Genetic factors also are believed to be involved, perhaps in the form of certain patterns of reduced immunocompetence, which might render the mother more susceptible to viral infection.

Common laparoscopic procedures in swine: a review.

Swine serve as excellent models for many laparoscopic procedures. As more operations are being performed laparoscopically, it is essential for the surgeon to have a good understanding of laparoscopic techniques. This manuscript reviews some commonly performed laparoscopic operations with an emphasis on models in swine. Porcine anatomy is generally similar to human anatomy with some minor differences. Practice on porcine models can help refine techniques and increase efficiency and skill.

Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of nonsentinel nodes following completion lymphadenectomy for melanoma.

INTRODUCTION: Most melanoma patients with sentinel lymph nodes (SLN) that are histologically positive for metastasis have no additional positive lymph nodes found upon completion lymph node dissection (CLND). Therefore, it has been suggested that CLND may not be required for all patients with positive SLN. This study was undertaken to determine the frequency with which nonsentinel nodes contain melanoma cells detected by RT-PCR. METHODS: Negative control lymph nodes were obtained from patients with breast and colon cancer. Positive control lymph nodes contained histologic evidence of melanoma. Nonsentinel nodes were harvested from melanoma patients undergoing CLND for a positive SLN. RT-PCR analysis for melanoma markers tyrosinase, gp100, MART-1, and MAGE-3 was performed, with Southern blot detection. The RT-PCR test was considered positive for the presence of melanoma cells if tyrosinase and at least one other marker were detected above background levels. RESULTS: RT-PCR analysis detected the presence of melanoma cells in 0/100 (0%) of negative control lymph nodes and 28/29 (97%) of positive control lymph nodes. A total of 117 histologically negative nonsentinel nodes from 13 patients who underwent CLND for positive SLN were evaluated. RT-PCR analysis was positive in 18/117 histologically negative nonsentinel nodes (15%) from 7/13 patients (54%). CONCLUSION: RT-PCR analysis suggests that when the SLN contains histologic evidence of melanoma, the remaining nodes in that basin are at risk for metastatic disease, despite the fact that these nonsentinel nodes are infrequently histologically positive.

Detection of beta-human chorionic gonadotropin mRNA as a marker for cutaneous malignant melanoma.

The beta chain of human chorionic gonadotropin (hCG) hormone is produced by fetal cells, gonadal cell tumors and several types of non-gonadal carcinoma. hCG is composed of an alpha and a beta chain, the latter of which can be used to distinguish the molecule from other related gonadotropin hormones. Detection of beta-hCG mRNA transcripts can be potentially useful as a marker to identify tumor cells. We devised a highly specific and sensitive assay to detect the atavistic expression of beta-hCG in cutaneous melanoma by RT-PCR. Twenty-four melanoma cell lines and 43 melanoma biopsies were evaluated for beta-hCG mRNA expression. An RT-PCR assay was developed to specifically distinguish beta-hCG poly-A mRNA from other related gonadotropin beta chains. This was performed by endonuclease digestion of a unique Sty 1 site in the beta chain, followed by Southern blot analysis with a beta-hCG cDNA probe. Of the 24 melanoma cell lines analyzed, 18 expressed beta-hCG mRNA. Analysis of melanoma biopsy specimens revealed beta-hCG mRNA expression in 17/25 melanoma-positive TDLN, and in only 5/15 non-lymphoid melanoma metastases. Beta-hCG mRNA expression had a 53% correlation to tyrosinase mRNA, a predominant melanoma marker. Beta-hCG mRNA was not detected in normal donor PBL and normal lymph nodes. Detection of beta-hCG mRNA expression may be a useful molecular marker to define a subset of malignant melanoma.

Quantifying HIV-1 RNA using the polymerase chain reaction on cerebrospinal fluid and serum of seropositive individuals with and without neurologic abnormalities.

We quantified HIV-1 RNA levels (copies per milliliter) in cerebrospinal fluid (CSF) and serum from subjects at various stages of HIV-1 disease and determined the relationship of RNA levels to clinical and neurologic disease status (HND) and to laboratory values. Ninety-seven HIV-1-seropositive men without CNS opportunistic infections, tumors, or neurosyphilis and 13 high-risk seronegative controls were included in the study. Each individual underwent a structured interview and physical and neurologic examinations, followed by standardized collection of blood and CSF. A custom-designed, fully automated polymerase chain reaction (PCR) system was used to perform a minimum of four separate amplifications per specimen, using two HIV-1 gag primer pairs. Southern blotting followed by hybridization with product-specific probes was used for post-PCR detection. The number of copies per milliliter was determined by relating unknowns to a built-in dilution-series standard curve using an image analysis system. HIV-1 RNA was detectable in 96% of the sera, 78% of the concentrated CSF samples, and 54% of the unconcentrated CSF samples. Serum RNA levels were significantly higher than in CSF. Serum RNA levels were significantly inversely correlated with CD4+ cell counts (p = -0.34; p = 0.03): i.e., higher RNA levels in seropositive subjects were associated with lower numbers of CD4+ cells. Serum RNA levels correlated positively with number of AIDS-related symptoms, dysfunction scores for total neurological examination, mental status score, cranial nerve score, and CNS motor signs score. Serum RNA levels did not correlate significantly with length of time on zidovudine therapy, intrathecal IgG synthesis rate, or albumin leakage. RNA levels in CSF significantly correlated only with intrathecal IgG synthesis rate and with serum RNA levels. These results confirm that serum levels of HIV-1 RNA correlate with HND and inversely correlate with CD4 counts, demonstrating that HND occurs predominantly in late stages of HIV-1 disease, although HIV-1 RNA can be detected in CSF from a majority of HIV-1-seropositive individuals at all stages of disease, which suggests that there can be early penetration of HIV into the CNS. However, HND can occur in the absence of high levels of CSF HIV-1 RNA. We also found that the concentration of HIV-1 in CSF is correlated with intrathecal IgG synthesis rate.

Molecular detection of tumor-associated antigens shared by human cutaneous melanomas and gliomas.

Both melanocytes and glial cells are derived embryologically from the neural ectoderm. Their malignant transformed counterparts, melanoma and glioma cells, respectively, may share common antigens. Numerous tumor-associated antigens have been identified in melanomas but only a few a gliomas. Using an established reverse transcriptase polymerase chain reaction plus Southern blot assay, we compared the mRNA expression of melanoma-associated antigens (MAAs) of melanomas to brain tumors primarily derived from glial cells. The MAAs studied included tyrosinase (Tyr), tyrosinase-related protein-1 and -2 (TRP-1 and TRP-2), gp100, human melanoma antigen-encoding genes 1 and 3 (MAGE-1 and MAGE-3), and melanotransferrin (p97). Glioblastoma multiforme (n = 21), anaplastic astrocytoma (n = 3), ependymoma (n = 2), meningioma (n = 3), oligodendroglioma (n = 1), and melanoma (n = 12) tumor specimens were assayed for MAA mRNA expression. Glioblastoma multiforme, astrocytoma, and melanoma cell lines were also assayed. We observed that individual MAA mRNAs were expressed in these brain tumors and cell lines at varying frequencies. The melanogenesis-pathway-related MAAs Tyr, TRP-1, TRP-2, and gp100 mRNAs were also expressed at different levels in normal brain tissues but at a much lower frequency than in glioblastoma multiforme and melanoma. MAGE-1 and MAGE-3 mRNA were expressed in different types of tumor specimens and cell lines but never in normal brain tissue. Tumor antigen p97 was expressed in all types of tumors and also in normal brain tissues. These studies demonstrate that melanomas and primary brain tumors express common MAAs and could be exploited in patients with malignant glioma by active specific immunotherapy against these common MAAs.