Functional transplant of megabase human immunoglobulin loci recapitulates human antibody response in mice.

We constructed two megabase-sized YACs containing large contiguous fragments of the human heavy and kappa (kappa) light chain immunoglobulin (Ig) loci in nearly germline configuration, including approximately 66 VH and 32 V kappa genes. We introduced these YACs into Ig-inactivated mice and observed human antibody production which closely resembled that seen in humans in all respects, including gene rearrangement, assembly, and repertoire. Diverse Ig gene usage together with somatic hypermutation enables the mice to generate high affinity fully human antibodies to multiple antigens, including human proteins. Our results underscore the importance of the large Ig fragments with multiple V genes for restoration of a normal humoral immune response. These mice are likely to be a valuable tool for the generation of therapeutic antibodies.

Obesity or diabetes: what is worse for the mother and for the baby?

OBJECTIVES: The aim of the present study is to evaluate pregnancy outcomes in a cohort of Caucasian pregnant women in relation to their body mass index and glucose tolerance status; the role of central fat distribution, as indicated by waist-to-hip circumference ratio, was also considered. METHODS: Seven hundred women were studied; they had gestational diabetes or impaired glucose tolerance (250) or normoglycaemia (450). Among them 117 had pre-pregnancy overweight/obesity (44 were obese), 133 hyperglycaemia, but normal weight, and 117 hyperglycaemia and overweight/obesity (42 were obese). RESULTS: Hypertension, cesarean delivery and prevalence of large-for-gestational age babies were higher in obese (both with normoglycaemia and hyperglycaemia), mainly in those with greater gestational weight gain and central fat distribution (waist-to-hip ratio > 0.90). Normal weight hyperglycaemic women showed better outcomes than obese normoglycaemic women did. In a multiple logistic regression model, obesity (OR=10.6; 95% CI 5.00-22.54) was directly related to hypertension, and independent predictors of cesarean section were: gestational hyperglycaemia (OR=1.78; 95% CI 1.21-2.62), gestational weight gain (OR=1.06; 95% CI 1.02-1.10), and central obesity (OR=1.51; 95% CI 1.02-2.24), while obesity (OR=4.48; 95% CI 2.30-8.71) gestational weight gain (OR=1.08; 95% CI 1.03-1.12) and central fat distribution (OR=1.81: 95% CI 1.12-2.93) were directly related to delivering larger babies, after multiple adjustments. CONCLUSION: These results suggest that pre-pregnancy obesity and gestational hyperglycaemia were independent risk factors for different adverse pregnancy and neonatal outcomes, while central distribution of fat, and gestational weight gain play an additive adverse role on these outcomes.

[Prevalence of antibody to hepatitis C virus in hospital personnel]. / Prevalenza dell'anticorpo contro il virus dell'epatite C nel personale ospedaliero.

UNLABELLED: Prevalence of antibody to hepatitis C virus (anti-HCV) has been widely investigated in many categories; however no data are available on hospital personnel. The aim of our study was to investigate whether hospital personnel are at risk for HCV infection. METHODS: sera collected during a prospective study on HBV infection in hospital workers done in our institution in 1985 were analyzed for the ELISA test for anti-HCV from Ortho Diagnostic System. Sera were stored at -20 degrees C and were never defrosted until tested. A population of a consecutive series of healthy volunteer blood donors was used as a control group. RESULTS: the anti-HCV prevalence was higher in hospital personnel, than in blood donors (4.5 versus 1.1, p less than 0.001, Odds Ratio 4.5, Confidence Limits 2.9-7.2). CONCLUSION: although anti-HCV is not an "ideal" test for epidemiological purposes, our study suggests that hospital personnel is at high risk for HCV infection.

Urinary incontinence: steps to evaluation, diagnosis, and treatment.

In this era of rapid, scientific medical advances, we still live with the myth that urinary incontinence should be accepted as a normal part of aging. Urinary incontinence, however, should not be considered a disease but rather a symptom or sign of an underlying problem. Patients with urinary incontinence now have many places to turn for advice and medical treatment. In addition to urologists, gynecologists, and geriatricians, nurses are actively involved in the evaluation and management of patients with urinary incontinence. The purpose of this article is to outline a systematic nursing approach to the evaluation, diagnosis, and treatment of patients with urinary incontinence in an office setting.

C-reactive protein and tumor necrosis factor-alpha in gestational hyperglycemia.

OBJECTIVES AND STUDY DESIGN: Increasing evidences support an inflammatory origin for gestational hyperglycemia. This paper aims at investigating, cross-sectionally and prospectively, the relationships between tumor necrosis factor-alpha (TNF-alpha) and C-reactive protein (CRP) levels in normoglycemic and hyperglycemic pregnancies of women with and without conventional risk factors for gestational diabetes (GDM). RESULTS: Both at simple and multiple correlations TNF-alpha levels are associated to fasting insulin, homeostasis model assessment-insulin resistance (HOMA-IR) values and gestational hyperglycemia, while high sensitivity CRP (hsCRP) levels to body mass index (BMI). Furthermore, the TNF-alpha levels of the second trimester and their increments in the third trimester are significant predictors of insulin levels measured at 32-36 weeks in the subgroup of hyperglycemic women with < or = 35 yr, BMI <25 kg/m2 and the absence of a first-degree relative with Type 2 diabetes (respectively, beta=1.1; 95%CI 0.66-1.48; p=0.002 and beta=1.0; 95%CI 0.36-1.66; p=0.02), in a multiple regression model, after multiple adjustments. In a second cohort of women at low risk for GDM (<25 yr, BMI <25 kg/m2 and absence of a first-degree relative with Type 2 diabetes), 24-28 weeks TNF-alpha levels are highly associated with corresponding insulin and HOMA values in the same model (respectively, beta=0.27; 95%CI 0.11-0.43; p=0.001 and beta=0.30; 95%CI 0.14-0.46; p<0.001). CONCLUSIONS: The data support the developing hypothesis that low-grade systemic inflammation is associated to GDM, in particular for pregnant women without conventional risk factors for gestational hyperglycemia, whose insulin resistance seems less explainable.

Cues to action: pelvic floor muscle exercise compliance in women with stress urinary incontinence.

Pelvic floor muscle exercises are recommended as an initial treatment to women with stress urinary incontinence. This treatment is often unsuccessful because of patient noncompliance. A post-test, experimental control group design was used to examine Pender's (1992) concept of an external cue to action, an audiocassette tape, to enhance patient compliance to pelvic floor exercises. Eighty-six women with urodynamically evaluated stress urinary incontinence participated through a Pelvic Floor Exercise Unit at a large teaching hospital. Patients received biofeedback training and written information to reinforce pelvic floor muscle exercises during a 45-min appointment with a nurse. Patients were instructed to perform the exercises for 10 min twice daily. Forty-three women randomly assigned to an experimental group received an audiocassette tape. Four to 6 weeks later all patients completed a researcher-developed questionnaire that was validity and reliability tested assessing pelvic floor exercise compliance. The 43 patients (100%) who received the audiocassette tape reported compliance with "routine" exercises. Twenty-two of 34 patients (65%) who did not receive the tape were compliant (P = 0.0003). Thirty-four of 41 patients (83%) who received the tape reported exercise compliance twice a day, while 4 of 34 patients (12%) in the control group were similarly compliant (P = 0.0000). The findings suggest adding an audiocassette tape to a pelvic floor exercise program enhances patient compliance for incontinent women compared to verbal and written instruction combined with biofeedback.

Transgenic mice as a source of fully human antibodies for the treatment of cancer.

The last two years have seen a renaissance of monoclonal antibodies for the treatment of disease. Of the eight antibodies currently approved for human therapy, two are for the treatment of cancer. In large part, the revival of antibodies has been driven by technology developments geared toward making antibodies less likely to elicit an anti-antibody response in humans. The development of transgenic mice, XenoMouse animals, capable of making fully human antibodies offers new opportunities for generating antibodies of therapeutic quality. Recently, this technology has been applied to the generation of a fully human antibody to the epidermal growth factor receptor. A description of the development of this antibody serves to illustrate the power and ease of use of XenoMouse technology.

A provocative maneuver to elicit cystometric instability: measuring instability at maximum infusion.

PURPOSE: We identify a provocative maneuver to enhance the sensitivity of cystometry in detecting detrusor instability when urge incontinence is suspected based on clinical history. MATERIALS AND METHODS: A total of 134 consecutive women with clinical urge incontinence underwent carbon dioxide cystometry between August 1995 and October 1996. The bladder was filled to maximal capacity with the patient supine. Six provocative maneuvers were performed consecutively to evoke detrusor instability, including lying supine, rising to a seated position, walking toward the bathroom, handwashing, coughing and sitting on the toilet with instructions not to void. Subjects were divided into 2 groups depending on the order of maneuvers. Sitting on the toilet was the last maneuver for group 1 (80 patients) and was in the middle of the sequence for group 2 (54). RESULTS: Sitting on the toilet evoked detrusor instability in 37.5% of group 1 and 53.8% of group 2. This maneuver with instructions not to void was the most provocative stimulus in eliciting detrusor instability with a detection rate of 68.4% for all subjects. CONCLUSIONS: Sitting on the toilet with the bladder at maximal capacity is the most provocative maneuver for detecting detrusor instability. The incidence of suspected detrusor instability is enhanced by using this test during routine cystometry.

Clinical experience with a balloon-tipped urethral insert for stress urinary incontinence.

A balloon-tipped urethral insert for control of urinary incontinence in women has undergone clinical trials and has been accepted for clinical use by the U.S. Food and Drug Administration. On the basis of results of a multicenter clinical trial, it was concluded that the device provides a safe and effective option for management of genuine stress incontinence and mild mixed incontinence in women. This article reviews appropriate patient selection, education, and training to optimize patient acceptance and efficacy of this urinary control insert.

Distinct roles for RAG-1 in the initiation of V(D)J recombination and in the resolution of coding ends.

Although RAG-1 and RAG-2 have been shown to be indispensible for V(D)J recombination, their exact role in this reaction remains unclear. Co-transfecting RAG-1 and RAG-2 expression vectors into NIH3T3 fibroblasts confers V(D)J recombination activity to these otherwise recombinationally inactive cells. In this report we have found that in transient transfections of mouse NIH3T3 fibroblasts with RAG-1 and RAG-2 and the appropriate recombination substrates, one RAG-1 expression vector, pRAG-1A, is capable of yielding both signal joints and coding joints, while another RAG-1 expression vector, pRAG-1B, yields only signal joints. The RAG-1 open reading frame for these two expression vectors is interchangeable, indicating that the inability to resolve coding joints is due to the 45-base pair difference found in the 5'-untranslated regions of these constructs. Differences in this region result in a 15-fold difference in gene expression when the luciferase coding region is substituted for the RAG-1 cDNA. This report provides evidence that RAG-1 may have a role in both the initiation of V(D)J recombination as well as the resolution of coding ends. The data also suggest that these RAG-1 activities may be dependent on different levels of RAG-1 expression.

Purification of the herpes simplex virus type 1 65-kilodalton DNA-binding protein: properties of the protein and evidence of its association with the virus-encoded DNA polymerase.

Using a combination of conventional column chromatography and velocity sedimentation, we have purified the 65-kilodalton DNA-binding protein (65KDBP) encoded by herpes simplex virus (HSV) greater than 625-fold. The HSV type 1 (HSV-1)-encoded DNA polymerase (pol) cofractionated with 65KDBP through DEAE-Sephacel, Blue Sepharose, and Mono Q columns and was only separated from 65KDBP by sedimentation through a glycerol gradient. Immunoaffinity columns containing monoclonal antibody (MAb) 6898 immunoglobulin effectively bound most of the HSV-1 pol activity which coeluted with 65KDBP. The pattern of reactivities of HSV-1/HSV-2 recombinants with MAbs specific for HSV-1 65KDBP or the HSV-2-infected cell-specific protein ICSP34,35 strongly suggests that these two species are serotype equivalents of the same protein. Taken together, all these data indicate that 65KDBP is a pol-associated protein and the HSV-1 counterpart of HSV-2 ICSP34,35 previously reported to have similar properties (P. J. Vaughan, D. J. M. Purifoy, and K. L. Powell, J. Virol. 53:501-508, 1985). Purified preparations of 65KDBP were capable of binding to double-stranded DNA, as determined by filter retention and mobility shift assays. The protein-DNA complex formed with 65KDBP was distinct from that produced by pol and could be further shifted by the addition of immunoglobulin specific for 65KDBP. These results demonstrate that 65KDBP has been purified substantially free from pol and indicate that DNA binding is an inherent property of the protein.

The essential 65-kilodalton DNA-binding protein of herpes simplex virus stimulates the virus-encoded DNA polymerase.

The 65-kilodalton DNA-binding protein (65KDBP) of herpes simplex virus type 1 (HSV-1), the product of the UL42 gene, is required for DNA replication both in vitro and in vivo, yet its actual function is unknown. By two independent methods, it was shown that the 65KDBP stimulates the activity of the HSV-1-encoded DNA polymerase (Pol). When Pol, purified from HSV-1-infected cells, was separated from the 65KDBP, much of its activity was lost. However, addition of the 65KDBP, purified from infected cells, stimulated the activity of Pol 4- to 10-fold. The ability of a monoclonal antibody to the 65KDBP to remove the Pol-stimulating activity from preparations of the 65KDBP confirmed that the activity was not due to a trace contaminant. Furthermore, the 65KDBP did not stimulate the activity of other DNA polymerases derived from T4, T7, or Escherichia coli. The 65KDBP gene transcribed in vitro from cloned DNA and translated in vitro in rabbit reticulocyte lysates also was capable of stimulating the product of the pol gene when the RNAs were cotranslated. The product of a mutant 65KDBP gene missing the carboxy-terminal 28 amino acids exhibited wild-type levels of Pol stimulation, while the products of two large deletion mutants of the gene could not stimulate Pol activity. These experiments suggest that the 65KDBP may be an accessory protein for the HSV-1 Pol.

The human immunoglobulin loci introduced into mice: V (D) and J gene segment usage similar to that of adult humans.

Variable gene segments of the human immunoglobulin loci are represented in the human peripheral repertoire at different frequencies. XenoMouse strains contain approximately 2 megabases of the human immunoglobulin heavy and kappa light chain loci that functionally recapitulate the human humoral immune system. Analysis of human antibody transcripts from XenoMouse spleens and lymph nodes revealed that V, D and J gene segment utilization from these unimmunized animals were nearly identical to the gene segment utilization reported for humans with extensive antigenic histories.

Production of protective human antipneumococcal antibodies by transgenic mice with human immunoglobulin loci.

Infections with Streptococcus pneumoniae remain a significant cause of morbidity and mortality. To gain insight into structure-function relationships for human antibodies to pneumococcal capsular polysaccharide (PPS), we studied the response of transgenic mice reconstituted with human immunoglobulin loci, XenoMouse, to PPS antigens in a pneumococcal vaccine. Enzyme-linked immunosorbent assays of sera from mice vaccinated with a 23-valent pneumococcal vaccine revealed that they produced serotype-specific human antibodies, with the greatest response being to the PPS of serotype 3 (PPS 3). Molecular sequence analysis of three monoclonal antibodies (MAbs) to PPS 3 generated from lymphoid cells from mice vaccinated with a 23-valent pneumococcal vaccine or a PPS 3-bovine serum albumin conjugate revealed that they all used heavy-chain immunoglobulin genes from the V(H)3 family, two expressed light chain genes from the human Vkappa1 family, and one expressed a mouse lambda light chain. The protective efficacy of the two MAbs was examined in mice. A 10-microgram dose of both, and a 1-microgram dose of one, significantly prolonged survival from a lethal serotype 3 infection in CBA/N mice. Our data show that XenoMouse mice produced protective, serotype-specific human antibodies to PPS 3, and they lend support to the proposal that these animals represent a useful model to study the human antibody response to PPS antigens.

Immunoglobulin gene usage and immunohistochemical characteristics of human monoclonal antibodies to the mitochondrial autoantigens of primary biliary cirrhosis induced in the XenoMouse.

The immunodominant antimitochondrial antibody (AMA) response in primary biliary cirrhosis (PBC) is directed against the E2 component of pyruvate dehydrogenase (PDC-E2). The nature of the clonal selection process is unclear, and to address this issue, we took advantage of a transgenic technology, XenoMouse, that contains 80% of the human immunoglobulin (Ig) variable gene repertoire and can produce high-affinity human antibodies to virtually any immunogen without evidence of clonal bias. We immunized mice with PDC-E2 to obtain 13 HmAbs, including 4 IgG(2) and 9 IgM isotypes. Immunoglobulin gene analysis was unique and demonstrated a clonal bias; the immunoglobulin gene usage was considerably different from other antibody responses analyzed in XenoMouse systems. Four of the 13 mAbs recognized the inner lipoyl domain of PDC-E2, 2 of 13 recognized the entire PDC-E2 molecule, 4 of 13 recognized PDC-E2 and OGDC-E2, 1 of 13 recognized OGDC only, 1 recognized BCOADC-E2 only, and 1 recognized an unidentified 100-kd mitochondrial protein. Immunohistochemical staining using these HmAbs produced mitochondrial staining of septal bile ducts in both PBC and control livers. Ig gene analysis showed that 7 of 13 HmAbs used the V(H)3 and 4 of 13 used VH4 gene repertoire, respectively. Three of 7 V(H)3 antibodies used the same Ig VH3-21 gene family found in human AMA from patients with PBC. The CDRs of these autoantibodies were slightly mutated when compared with the sequences present within the Ig germline genes. In conclusion, the XenoMouse not only recapitulates the unique specificity and restriction of PBC patients, but indicates that the autoantibodies are derived from a restricted clonal selection process. Such data suggest that the original immunogen leads to somatic mutation without subsequent development of determinant spreading.