Class I major histocompatibility complex anchor substitutions alter the conformation of T cell receptor contacts.

An immunogenic peptide (GP2) derived from HER-2/neu binds to HLA-A2.1 very poorly. Some altered-peptide ligands (APL) of GP2 have increased binding affinity and generate improved cytotoxic T lymphocyte recognition of GP2-presenting tumor cells, but most do not. Increases in binding affinity of single-substitution APL are not additive in double-substitution APL. A common first assumption about peptide binding to class I major histocompatibility complex is that each residue binds independently. In addition, immunologists interested in immunotherapy frequently assume that anchor substitutions do not affect T cell receptor contact residues. However, the crystal structures of two GP2 APL show that the central residues change position depending on the identity of the anchor residue(s). Thus, it is clear that subtle changes in the identity of anchor residues may have significant effects on the positions of the T cell receptor contact residues.

T cell activity after dendritic cell vaccination is dependent on both the type of antigen and the mode of delivery.

Previous work in both human and animal models has shown that CTL responses can be generated against proteins derived from tumors using either peptide-pulsed dendritic cells (DCs) or nucleic acids from the tumor transfected into autologous DCs. Despite the efficacy of this approach for vaccine therapy, many questions remain regarding whether the route of administration, the frequency of administration, or the type of Ag is critical to generating T cell responses to these Ags. We have investigated methods to enhance CTL responses to a peptide derived from the human proto-oncogene HER-2/neu using mice containing a chimeric HLA A2 and H2Kb allele. Changes in amino acids in the anchor positions of the peptide enhanced the binding of the peptide to HLA-A2 in vitro, but did not enhance the immunogenicity of the peptide in vivo. In contrast, when autologous DCs presented peptides, significant CTL activity was induced with the altered, but not the wild-type, peptide. We found that the route of administration affected the anatomic site and the time to onset of CTL activity, but did not impact on the magnitude of the response. To our surprise, we observed that weekly administration of peptide-pulsed DCs led to diminishing CTL activity after 6 wk of treatment. This was not found in animals injected with DCs every 3 wk for six treatments or in animals initially given DCs weekly and then injected weekly with peptide-pulsed C1R-A2 transfectants.

Poor binding of a HER-2/neu epitope (GP2) to HLA-A2.1 is due to a lack of interactions with the center of the peptide.

Class I major histocompatibility complex (MHC) molecules bind short peptides derived from proteins synthesized within the cell. These complexes of peptide and class I MHC (pMHC) are transported from the endoplasmic reticulum to the cell surface. If a clonotypic T cell receptor expressed on a circulating T cell binds to the pMHC complex, the cell presenting the pMHC is killed. In this manner, some tumor cells expressing aberrant proteins are recognized and removed by the immune system. However, not all tumors are recognized efficiently. One reason hypothesized for poor T cell recognition of tumor-associated peptides is poor binding of those peptides to class I MHC molecules. Many peptides, derived from the proto-oncogene HER-2/neu have been shown to be recognized by cytotoxic T cells derived from HLA-A2(+) patients with breast cancer and other adenocarcinomas. Seven of these peptides were found to bind with intermediate to poor affinity. In particular, GP2 (HER-2/neu residues 654-662) binds very poorly even though it is predicted to bind well based upon the presence of the correct HLA-A2.1 peptide-binding motif. Altering the anchor residues to those most favored by HLA-A2.1 did not significantly improve binding affinity. The crystallographic structure shows that unlike other class I-peptide structures, the center of the peptide does not assume one specific conformation and does not make stabilizing contacts with the peptide-binding cleft.

Childhood victimization and subsequent risk for promiscuity, prostitution, and teenage pregnancy: a prospective study.

OBJECTIVES: This study examined the extent to which being abused and/or neglected in childhood increases a person's risk for promiscuity, prostitution, and teenage pregnancy. METHODS: A prospective cohorts design was used to match, on the basis of age, race, sex, and social class, cases of abused and/or neglected children from 1967 to 1971 with nonabused and nonneglected children; subjects were followed into young adulthood. From 1989 to 1995 1196 subjects (676 abused and/or neglected and 520 control subjects were located and interviewed. RESULTS: Early childhood abuse and/or neglect was a significant predictor of prostitution for females (odds ratio [OR] = 2.96). For females, sexual abuse (OR = 2.54) and neglect (OR = 2.58) were associated with prostitution, whereas physical abuse was only marginally associated. Childhood abuse and neglect were not associated with increased risk for promiscuity or teenage pregnancy. CONCLUSIONS: These findings strongly support a relationship between childhood victimization and subsequent prostitution. The presumed causal sequence between childhood victimization and teenage pregnancy may need to be reevaluated.

Role of p53 immunohistochemistry in differentiating reactive gliosis from malignant astrocytic lesions.

P53 immunohistochemistry has been used to distinguish between malignant tumors and morphologically similar benign processes. In the central nervous system, a major diagnostic dilemma is caused by overlapping features of benign reactive astrocytic lesions and low-grade astrocytomas, especially with small biopsies. P53 immunoreactivity in astrocytes could be useful in differentiating benign reactive lesions from malignant astrocytomas. An immunohistochemical study on 110 brain lesions from 108 patients using a monoclonal antibody (DO-7) against p53 protein was conducted. Using the modified Ringertz and World Health Organization system, the specimens included 22 astrocytomas, 12 anaplastic astrocytomas, 42 glioblastoma multiforme tumors, three nonglial tumors, and 56 reactive astrocytic lesions to 25 neoplasms, nine infectious processes, six cerebrovascular disorders,one metabolic disorder, two vascular malformations, eleven degenerative/demyelinating lesions, and two unknown primary lesions. Immunoreactive astrocytic tumors included 12 (54%) astrocytomas, nine (75%) anaplastic astrocytomas, and 38 glioblastoma multiforme tumors (90%). Among the reactive astrocytic lesions, only five (9%) cases of progressive multifocal leukoencephalopathy were immunoreactive. These data demonstrate that p53 immunoreactivity in astrogliosis is unusual but is to be expected in astrocytomas and can help to differentiate reactive from neoplastic astrocytic lesions.

Substance use/misuse among female prostitutes and female arrestees.

The literature has documented the correlation between prostitution and drug use/misuse. This study probed demographics, drug use experimentation and frequency, age of first drug use, and drug use treatment among 53 female prostitutes and 47 female arrestees. The results indicated that: 1) prostitutes were likely to drop out of school; 2) significantly more prostitutes had tried drugs, had used drugs with greater frequency and had begun drug/alcohol use at younger ages. These results imply that: 1) early drug/alcohol use and withdrawal from school could leave young women vulnerable and at higher risk of becoming involved in prostitution; and 2) drug use treatment and intervention needs to begin at younger ages.

DNA fingerprinting by pulsed field gel electrophoresis and ribotyping to distinguish Pseudomonas cepacia isolates from a nosocomial outbreak.

We typed 40 isolates of Pseudomonas cepacia obtained from patients involved in a single outbreak using pulsed field gel electrophoresis and ribotyping. All isolates from the majority of the patients, 16 of 18 (89%), were included in a single group. These typing methods should aid in the clarification of the epidemiology of infection with P. cepacia.

Molecular analysis of hemolytic and phospholipase C activities of Pseudomonas cepacia.

By using a gene-specific fragment from the hemolytic phospholipase C (PLC) gene of Pseudomonas aeruginosa as a probe and data from Southern hybridizations under reduced stringency conditions, we cloned a 4.2-kb restriction fragment from a beta-hemolytic Pseudomonas cepacia strain which expressed hemolytic and PLC activities in Escherichia coli under the control of the lac promoter. It was found, by using a T7 phage promoter-directed expression system, that this DNA fragment carries at least two genes. One gene which shares significant DNA homology with both PLC genes from P. aeruginosa encodes a 72-kDa protein, while the other gene encodes a 22-kDa protein. When both genes on the 4.2-kb fragment were expressed from the T7 promoter in the same cell, hemolytic and PLC activities could be detected in the cell lysate. In contrast, when each individual gene was expressed in different cells or when lysates containing the translated products of each separate gene were mixed, neither hemolytic activity nor PLC activity could be detected. Clinical and environmental isolates of P. cepacia were examined for beta-hemolytic activity, PLC activity, sphingomyelinase activity, and reactivity in Southern hybridizations with a probe from P. cepacia which is specific for the larger gene which encodes the 72-kDa protein. There were considerable differences in the ability of the different strains to express hemolytic and PLC activities, and the results of Southern DNA-DNA hybridizations of the genomic DNAs of these strains revealed considerable differences in the probe-reactive fragments between high- and medium-stringency conditions as well as remarkable variation in size and number of probe-reactive fragments among different strains. Analysis of the genomic DNAs from hemolytic and nonhemolytic variants of an individual strain (PC-69) by agarose gel electrophoresis. Southern hybridization, and transverse alternating pulsed field gel electrophoresis suggests that the conversion of the hemolytic phenotype to the nonhemolytic phenotype is associated with either the loss of a large plasmid (greater than 200 kb) or a large deletion of the chromosome of P. cepacia PC-69.

Cholangiocarcinoma in association with multiple biliary microhamartomas.

The rarity of cholangiocarcinoma occurring in von Meyenburg complexes is well appreciated. We describe the case of a 35-year-old man found to have cholangiocarcinoma in association with multiple biliary microhamartomas of the liver. Areas of ductal proliferation and atypia within the bile duct hamartomas suggest malignant transformation to cholangiocarcinoma.

Fine needle aspiration biopsy in clinical management of head and neck tumors.

Ninety-five percent (195) of 203 fine needle aspiration biopsies (FNAB) of head and neck specimens contained adequate tissues for histologic evaluation. No complications or needle tract recurrences were identified. Out of 135 patients whose surgical excision followed FNAB, 5% (7/135) of the biopsies were nondiagnostic. Correlation of cytologic and histologic findings of the remaining 128 FNAB revealed a sensitivity rate of 82% (46/56), a specificity rate of 99% (71/72), and a positive predictive of value of 98% (46/47). The diagnostic accuracy of FNAB was better with salivary gland and cervical node specimens than with thyroid, skin, and subcutaneous specimens. Fine needle aspiration biopsy may be considered as the first diagnostic step in the evaluation of the mass of the head and neck region, if the nondiagnostic aspiration rate is low and the diagnostic accuracy is high.

Ganglioneuroma of the terminal ileum. An unusual case of occult gastrointestinal bleeding.

Occult gastrointestinal (GI) bleeding from small-bowel tumors is relatively uncommon, and bleeding from neural tumors is rare. A case of chronic bleeding from a ganglioneuroma that led to ileal ulceration is presented. This case documents the important role of exploratory celiotomy and thorough exploration of the abdomen in carefully selected patients with occult GI blood loss. In this case, a complete preoperative evaluation was negative, but a nondirected celiotomy resulted in diagnosis and successful treatment.

Breast cancer risk: a review of definitions and assessments of risk.

The histopathological and biochemical characteristics of cells and multicellular structure of benign and malignant breast changes have highly significant implications as to the risk of acquiring and dying of breast cancer. Consequently, every breast biopsy merits highly specific histopathological characterization as well as assay for hormone receptors. Certain aspects of a woman's personal and family history may be associated with increased or decreased risk. Clinical application of these variables to the prediction of future outcome requires an understanding of the definitions of risk. These definitions must then be applied appropriately when assessing risk. The definition of risk used must be explicitly stated and consistently used. Provided is a review of the definitions of risk and the risk of acquiring breast cancer according to age, family history, and histopathological characteristics of benign breast biopsies. The highly variable relative risk of dying from breast cancer when diagnosed is also reviewed.

Localization and pattern of expression of a female specific mRNA in Schistosoma mansoni.

To understand mechanisms involved in sex-specific gene expression in Schistosoma mansoni, a cDNA (fs800) was isolated that hybridized to an 800 nucleotide mRNA present in high levels only in mature female worms. The fs800 cDNA sequence was characterized by two long open reading frames and central stretches of repeated amino acids. Fs800 did not share similarities with other known sequences in computer searches. In situ hybridization, however, revealed that the mRNA corresponding to fs800 was found only in female vitelline cells, suggesting that the product of this gene may be involved in the production or function of eggs. Fs800 is developmentally regulated as expression of this gene is dependent on the maturity of female worms. Furthermore, during in vitro culture, when female worms are known to stop egg production, expression of fs800 selectively ceased.

Thickness as prognostic aid in upper aerodigestive tract cancer.

A retrospective review of records and microscopic slides was carried out on 151 patients, encompassing nine specific upper aerodigestive tract cancer sites, correlating depth of invasion with node metastases and outcome. In this preliminary descriptive study, thickness was found to be more closely related to node metastasis and to survival than was surface diameter in middle-stage tumors, particularly in tongue, floor of the mouth, buccal mucosa, gum, and soft palate sites. Thickness, depth of penetration, and bone involvement appear to represent the degree of general tumor aggressiveness better than does surface extent. A substitution of thickness measurement for surface diameter (T) in the present TNM staging system is suggested.

Localization of discontinuous epitopes of herpes simplex virus glycoprotein D: use of a nondenaturing ("native" gel) system of polyacrylamide gel electrophoresis coupled with Western blotting.

Previously, a panel of monoclonal antibodies (MCAb) was used to define specific epitopes of herpes simplex virus glycoprotein D (gD) (R. J. Eisenberg et al., J. Virol. 53:634-644, 1985). Three groups of antibodies recognized continuous epitopes; group VII reacted with residues 11 to 19 of the mature protein (residues 36 to 44 of the predicted sequence), group II reacted with residues 272 to 279, and group V reacted with residues 340 to 356. Four additional antibody groups recognized discontinuous epitopes of gD, since their reactivity was lost when the glycoprotein was denatured by reduction and alkylation. Our goal in this study was to localize more precisely the discontinuous epitopes of gD. Using a nondenaturing system of polyacrylamide gel electrophoresis ("native" gel electrophoresis) coupled to Western blotting, we analyzed the antigenic activity of truncated forms of gD. These fragments were generated either by recombinant DNA methods or by cleavage of purified native gD-1 (gD obtained from herpes simplex virus type 1) and gD-2 (gD obtained from herpes simplex virus type 2) with Staphylococcus aureus protease V8. Antibodies in groups III, IV, and VI recognized three truncated forms of gD-1 produced by recombinant DNA methods, residues 1 to 287, 1 to 275, and 1 to 233. Antibodies in group I recognized the two larger forms but did not react with the gD-1 fragment of residues 1 to 233. On the basis of these and previous results, we concluded that a protion of epitope I was located within residues 233 to 259 and that epitopes III, IV, and VI were upstream of residue 233. Antibodies to continuous epitopes identified protease V8 fragments of gD-1 and gD-2 that contained portions of either the amino or carboxy regions of the proteins. None of the V8 fragments, including a 34K polypeptide containing residues 227 to 369, reacted with group I antibodies. This result indicated that a second portion of epitope I was located upstream of residue 227. Two amino-terminal fragments of gD-1, 33K and 30K, reacted with group III, IV, and VI antibodies. A 33K fragment of gD-2 reacted with group III antibodies. Based on their size and reactivity with endo-beta-N-acetylglycosaminidase F, we hypothesized that the 33K and 30K molecules represented residues 1 to 226 and 1 to 182 of gD-1, respectively. These results suggest that epitopes III, IV, and VI are located within the first 182 residues of gD.(ABSTRACT TRUNCATED AT 400 WORDS)

Association of chronic cystic mastopathy, xeromammographic patterns, and cancer.

The Breast Cancer Demonstration and Detection Project in Louisville (BCDDP-L) screened 10,128 women for cancer. From this screening, another project evolved wherein those patients diagnosed as having chronic cystic mastopathy (CCM) were followed over a 10-year period to evaluate any association between CCM and breast cancer. In all, 1396 breast biopsies were performed, with 165 cancers being diagnosed either on initial screening or during subsequent years. Three of these are excluded, since histopathologic slides could not be obtained for central review. Of this group, cancer was associated with CCM in 116 specimens and without CCM in 46 specimens. One subset of 355 patients with biopsy-proven CCM but no breast cancer was followed for 6 to 12 years, for a total of 2443.5 woman-years of observation. Within this subset, a total of only four cancers occurred (4 cancers/2443.5 woman-years for 0.00164 cancers/woman-years). This incidence is not significantly different from the expected value. However, an estimate is provided as to the power of the test that could be obtained from a larger sample size derived from other BCDDPs. This group of 355 women was sorted into subsets by establishing a matrix matching ten histopathologic subdivisions of CCM against six subdivisions of Wolfe's xeromammographic (XM) patterns. The numbers of cancers in each cell of this matrix is reported. The results found no concentration of these four cancers in this matrix.

Primary malignant melanomas of the lung and adrenal.

Malignant melanoma originating outside the skin, juxtacutaneous mucous membranes, eyes, and leptomeninges is a very rare neoplasm. Two such primary visceral malignant melanomas from the lung and adrenal are described in detail.

Endoarterial pulmonary metastasis of malignant trophoblast associated with a term intrauterine pregnancy.

A previously healthy gravida 4, para 3, developed preclampsia and progressive dyspnea at the 37th gestational week and had bilateral pulmonary infiltrates on chest roentgenogram. She delivered a healthy, term, male infant with a normal appearing placenta. Postpartum, her respiratory status gradually worsened. A lung biopsy on the 20th postpartum day revealed intravascular trophoblasts, diffuse arteriolar thrombosis with pulmonary infarction, and subacute interstitial pneumonitis. Combination chemotherapy was instituted, but the patient died from respiratory insufficiency.

The association of pathologic and mammographic characteristics of primary human breast cancers with "slow" and "fast" growth rates and with axillary lymph node metastases.

This article reports statistically significant associations existing between the clinical, mammographic and histopathologically classified properties of mammary cancers occurring in the population of 10,120 women screened in the BCDDP at the University of Louisville over a 5-year period and the propensity to grow "fast" and "slow" and metastasize or not metastasize to the axillary lymph nodes. Fast cancers, divided into two defined subsets as "fast 1" and "fast 2," are those surfacing in the intervals between mammograms. The faster cancers exhibited a significant absence of calcification, were discovered in younger patients and resulted in a shorter 5-year cumulative survival rate (fast 1 = 74 +/- 9% to slow = 94 +/- 4%). In addition to growth rates, another index of virulence in small cancers is the early appearance of metastases in the axillary lymph nodes. The absence of microscopic calcifications and the presence of lymphatic invasion around the primary cancer site were significantly associated with the presence of axillary metastases. Other factors associated with the occurrence of axillary metastases were a higher mitotic index, poor cellular differentiation and a larger size of cancer at diagnosis. The author's results confirm that interval surfacing cancers are biologically different and are not comparable to cancers discovered by scheduled screens. Cancers that metastasize to lymph nodes while very small have properties in common with these interval surfacing and, presumably, faster growing cancers.