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F Scinicariello

Publications and source records attributed to F Scinicariello.

12 recordsLinked to original sources
PubMed2001

Intraspecies heterogeneity of immunoglobulin alpha-chain constant region genes in rhesus macaques.

Immunoglobulin A (IgA) is the major antibody class present in external secretions and is also an important component of serum immunoglobulins. On mucosal surfaces, IgA represents a first line of defence by neutralizing invading pathogens. The number of IgA constant-region genes (C alpha) present in different mammalian species is variable. Immunoglobulin C alpha genes differ mainly in the sequences located in the hinge region. IgA molecules, whose hinge regions are remarkably similar to those of the respective human molecules, are present in hominoid primates. In this report, we show that two alleles of a single immunoglobulin C alpha are present in rhesus macaques (Macaca mulatta). In addition, we show that intraspecies immunoglobulin C alpha allelic polymorphism is very high in this non-human primate species. Specifically, five different hinge regions, some of which are proline-rich, were identified from a total of eight rhesus macaque immunoglobulin C alpha-chains. The five hinge regions were different from those present in hominoid primates, both in length and in sequence. These results represent the first example of high levels of intraspecies immunoglobulin constant-region variability and suggest that IgAs of variable structure and function may be present in rhesus macaques. As rhesus macaques are widely used as animal models for the development of vaccines for acquired immune deficiency syndrome (AIDS), the possible presence of structurally and functionally variable IgA molecules in different animals should be taken into account when designing experimental strategies to induce mucosal antibody responses to human immunodeficiency virus (HIV).

Alleles↗
PubMed1997

DNA-based immunization induces anti-CD4 antibodies directed primarily to native epitopes.

DNA-based immunization is one of the most promising strategies to induce protective immunity against a variety of pathogens, presenting clear advantages as compared to the use of recombinant antigens. One of these advantages might be the ability to induce antibodies directed primarily against conformational determinants, as compared to immunization with recombinant proteins. To test this possibility, we have analyzed the antibody responses induced in mice by immunization with either recombinant soluble CD4 (rCD4) or by immunization with plasmid DNA-encoding CD4 (CD4-DNA). Mice immunized with CD4-DNA had lower titers of antibodies able to recognize rCD4 than mice immunized with rCD4. However, immunization with CD4-DNA induced antibodies reactive with the native cell surface CD4 molecule in all mice, whereas only two out of five mice immunized with rCD4 produced antibodies reactive with cell surface CD4, thus demonstrating that the genetic immunization approach may lead to an antibody response more consistent and superior at a qualitative level as compared to immunization with the corresponding recombinant protein. In addition, differences in the kinetics of appearance of antibodies directed against the native CD4 molecule were observed between mice immunized with CD4-DNA or rCD4. In the first case, antibodies reacting with cell surface CD4 were present 28 days after the first immunization, whereas mice immunized with rCD4 produced antibodies directed against the native molecule only following a booster injection. Finally, the two groups of mice produced antibodies with a different isotype distribution. No clear predominance of a specific IgG subclass was detected in the antibody population produced in response to DNA immunization. Conversely, mice immunized with rCD4 produced predominantly antibodies of the IgG1 isotype, indicating generation of a TH2 response. Together, results from this study indicate that the CD4 molecule endogenously produced following DNA immunization is expressed, at least partially, in a native conformation. This feature confers a major advantage to the DNA immunization approach as compared to immunization with the corresponding recombinant protein, which seems to elicit antibodies predominantly directed to epitopes uniquely expressed on the recombinant molecule.

Animals↗
PubMed1995

Risk of venereal B virus (cercopithecine herpesvirus 1) transmission in rhesus monkeys using molecular epidemiology.

The importance of venereal modes of B virus (cercopithecine herpesvirus 1) transmission was evaluated in 49 rhesus monkeys tested at necropsy. Antibodies to B virus were demonstrated in 19 monkeys, but no active viral shedding was detected in mucosal swabs collected at death. The polymerase chain reaction demonstrated presence of the ICP 18.5 (UL28) gene of B virus in neuronal tissues of 15 monkeys presumed to be latently infected, including 12.8% of trigeminal and 22.9% of lumbosacral ganglia pools. Two monkeys tested positive at both sites. Breeding history was predictive of B virus seropositivity (odds ratio, 1.64; 95% confidence interval, 1.21-2.23; P < .05). The population attributable risk of B virus seropositivity due to breeding was 22.7%, similar to the proportion of monkeys with B virus DNA in neuronal tissues subserving the genital region. Sexual contact is a significant, but not predominant, mode of B virus transmission between monkeys.

Age Factors↗
PubMed1994

Occurrence of human papillomavirus and p53 gene mutations in Kaposi's sarcoma.

Epidemiological evidence indicates that a sexually transmitted agent might be involved in the etiopathogenesis of Kaposi's sarcoma (KS). The prevalence of human papillomaviruses (HPV) in KS has been the focus of several investigations that have reported conflicting data. In addition, mutations of the p53 gene, which are the most frequent genetic changes found in human tumors, are absent in HPV-positive cervical carcinomas leading to the hypothesis that the function of p53 in HPV-positive tumors is inactivated through binding to the E6 viral gene product. Thus, the present study was designed to investigate the presence of HPV and p53 gene mutations in 17 formalin-fixed, paraffin-embedded KS [7 acquired immunodeficiency syndrome-KS (AIDS-KS) and 10 classic KS] specimens. HPV 6 DNA was detected in an AIDS-KS specimen, and HPV 16 DNA was found in 3 classic KS specimens. Heterozygous mutations of the p53 gene were detected in five (24%) KS samples. No p53 mutations were detected in HPV-positive KS. The p53 mutations were mainly transversions (four of five). These data indicate that HPV may contribute to the pathogenesis of some cases of KS and that p53 alteration may represent a key event in the progression of the malignancy.

DNA, Viral↗
PubMed1993

Rapid detection of B virus (herpesvirus simiae) DNA by polymerase chain reaction.

Rapid diagnosis of B virus (herpesvirus simiae) infection in humans followed by early antiviral treatment is essential for the patient's survival. To improve laboratory diagnosis of B virus infections, a polymerase chain reaction (PCR)-based test using synthetic oligonucleotide primers and probe was developed to detect B virus DNA in clinical samples. After the specificity of the PCR was assessed for detection of several B virus isolates, the method was used to investigate human and monkey specimens, and results were compared with those obtained by viral culture. PCR appeared to be more sensitive than conventional virus isolation and thus of practical use for a rapid identification of B virus infection when conventional viral cultures are negative.

Animals↗
PubMed1992

Human papillomavirus 16 exhibits a similar integration pattern in primary squamous cell carcinoma of the penis and in its metastasis.

BACKGROUND: Human papillomaviruses (HPV) are among the most common causes of sexually transmitted viral infections in the United States, and HPV types 16, 18, and others have been strongly linked with the development of cervical cancer. DNA from these oncogenic HPV types also has been detected in biopsy specimens of penile intraepithelial and invasive neoplasms, indicating a causal role of these viruses in the malignant transformation of these tissue. METHODS: Southern blot analysis and two-dimensional gel electrophoresis were used to investigate the presence and physical state of HPV in a patient with metastatic penile carcinoma. RESULTS: The presence of HPV 16 DNA integrated into the host's genome was documented in a primary penile squamous cell carcinoma and its lymph node metastasis. CONCLUSIONS: The identical restriction endonuclease cleavage patterns for HPV 16 in both the primary tumor and its lymph node metastasis indicate that both tumors arose from a single clonal event. This finding provides evidence of a causal role of HPV in squamous cell carcinoma of male genitalia.

Adult↗
PubMed1992

p53 mutations in basal cell carcinomas.

Genomic DNA from 14 basal cell carcinoma biopsies was screened for the presence of mutations in the p53 gene, using the polymerase chain reaction followed by direct DNA sequencing. Heterozygous mutations were detected in 7 of 14 (50%) samples investigated. All mutations were G:C-A:T transitions, and five (71%) of these mutations were transitions at hot spots with CpG sites, three at codon 248 and two at codon 273. The striking similarity of the type of mutations detected in this study and with the UV mutagenesis studies reported in literature suggest the hypothesis that UV may act on the p53 gene in a carcinogenic-specific fashion.

Base Sequence↗
PubMed1992

Human papillomavirus type 16 found in primary transitional cell carcinoma of the Bartholin's gland and in a lymph node metastasis.

We report a case of primary transitional cell carcinoma of the Bartholin's gland and its lymph node metastasis that contained HPV 16 sequences by polymerase chain reaction. The physical state of HPV 16 DNA in the primary cancer was investigated by Southern blot analysis which showed the presence of the episomal form of viral DNA. Our findings of HPV 16 DNA in the transitional cell carcinoma of the Bartholin's gland and its metastasis would indicate that both tumors arose from a single clonal event, thus providing evidence that the HPV 16 may have an oncogenic potential in this rare malignancy even in the episomal state.

Adult↗
PubMedDate not supplied

Detection of human papillomavirus in primary hepatocellular carcinoma.

Human papillomaviruses (HPV) have been linked causally to some human cancers such as cervical carcinoma. To determine whether any additional type of human malignancy contained HPV DNA, we examined 16 hepatocellular carcinoma (HCC) specimens by Southern blot technique and by polymerase chain reaction (PCR). One HCC contained HPV 16 DNA as demonstrated by both Southern blot and PCR. Two other HCC samples contained HPV 18-related nucleotide sequences by PCR but were negative by Southern blot of genomic DNA. HPV could have been carried via blood to the liver, thus indirectly supporting the presence of an HPV viremia. Our findings suggest that oncogenic HPV might constitute a cofactor acting synergistically with hepatitis B virus (HBV) in the development of the HCC in these patients. Alternatively, the presence of HPV in the tumor tissue might be the result of an opportunistic infection.

Autoradiography↗