|
| ||
|
|
||
Binding Antibody (binding + antibody)
Selected AbstractsIdentification and Repair of Positive Binding Antibodies Containing Randomly Generated Amber Codons from Synthetic Phage Display LibrariesBIOTECHNOLOGY PROGRESS, Issue 3 2006Warren D. Marcus Phage display technology allows for the rapid isolation and characterization of monoclonal antibodies that have vast potential for therapeutic and diagnostic applications. However, the panning process, which utilizes a host strain that suppresses termination by the amber codon, has an inherent bias toward clones containing randomly generated amber stop codons, complicating identification of positive binding antibodies when the antibody genes are finally expressed in a nonsupressor host. Here, we perform biopanning against a Histone 2A peptide using streptavidin- or anti-biotin-coated beads. After four rounds, a dominant clone is characterized but contains a spurious amber stop codon. A protocol is given that readily corrects the amber codon, allowing for soluble antibody production once the phagemid is transformed into a nonsuppressor bacterial strain. This work also highlights the ability to isolate antibodies against a protein antigen by using only a small peptide (15 amino acids) representing a portion of the antigen. [source] CD40-mediated enhancement of immune responses against three forms of influenza vaccineIMMUNOLOGY, Issue 1 2007Caterina Hatzifoti Summary There is potential for influenza A infections to cause massive morbidity and mortality. Vaccination may be the primary defence against pandemic influenza, and potential pandemic'flu vaccines may be produced conventionally, in embryonated eggs, or as recombinant protein or synthetic peptide vaccines. However the vaccines are produced, the supply may be limiting, and it will be important to enhance the immunogenicity of the vaccines as much as possible. We have shown that conjugation to CD40 binding antibody is a very efficient way of enhancing immune responses against model antigens, but were interested in assessing the effectiveness of this system using influenza vaccines. We produced conjugates of CD40 monoclonal antibody (mAb) and isotype control with three potential influenza vaccines: a peptide-based vaccine containing T- and B-cell epitopes from virus haemagglutinin; a whole, killed virus vaccine; and a commercially produced split virus vaccine. CD40 mAb conjugates in each case were more immunogenic, but the adjuvant effect of CD40 conjugation was greatest with the split vaccine, where antibody responses were enhanced by several hundred-fold after a single immunization, and lymphocyte proliferation in response to antigen in vitro was also strongly enhanced. [source] Mucous membrane pemphigoid, thymoma, and myasthenia gravisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 9 2000Haideh Yazdani Sabet In November 1997, approximately 1 year before being evaluated at the Mayo Clinic, Rochester, a 63-year-old woman presented with erosive tongue lesions that were diagnosed by her physician as oral lichen planus. The lesions responded well to 3 months of treatment with systemic and topical corticosteroids and topical antiyeast medication. She stopped taking the medications and had a relapse. A few months after the oral lesions developed, her left eyelid became ptotic. Results of magnetic resonance imaging of her brain were normal, and the ptosis resolved spontaneously after 2 weeks. One year later, her right eyelid began to droop, and the results of edrophonium testing were positive. She was prescribed prednisone, 30 mg daily, and pyridostigmine, as needed. The ptosis improved, but never fully resolved. Radiography revealed a left ,,thyroid nodule,'' but computed tomography did not show a mediastinal mass. She was advised to have the ,,nodule'' removed surgically and came to the Mayo Clinic, Rochester, for a second opinion. Her medical history was significant for the following: tinnitus, glaucoma, early bilateral cataracts, and long-standing hypertension, for which she took losartan, 50 mg twice daily. Other medications included: prednisone, 30 mg daily; pyridostigmine as needed; famotidine, 40 mg daily; and eyedrops for glaucoma. She denied any history of hyperthyroidism or hypothyroidism, head and neck irradiation, family history of thyroid disease, or diplopia. Hepatitis serologic studies revealed hepatitis B exposure and recovery, hepatitis C immunity, and a previous hepatitis A viral infection. On examination at the Mayo Clinic, Rochester, an erosive hypertrophic plaque was noted on the posterior dorsal half of the tongue, and vesicles and erythematous erosions on the hard and soft palates ( Fig. 1a). A lace-like white pattern was seen on the buccal mucosa bilaterally, and a small erosive patch on the left buccal mucosa ( Fig. 1b). Ocular and nasal mucous membranes were normal in appearance, and there were no pertinent skin findings. Dermatopathologic examination of an excisional biopsy specimen from the left dorsum of the tongue demonstrated an ulcer with epitheliomatous hyperplasia and a granulomatous reaction, presumably due to yeast infection. Silver staining showed hyphae and yeast at the base of the tongue ulcer. The results of the direct immunofluorescence study were negative and revealed no lichenoid changes on hematoxylin and eosin staining. Indirect immunofluorescence testing of the serum revealed a 1 : 80 titer of basement membrane zone antibodies, reflecting pemphigoid. This test was positive on repeat study. Salt-split skin on monkey esophagus revealed an epidermal pattern of basement membrane zone antibodies. Treatment included fluocinonide gel applied to the involved areas four times daily and oral antiyeast therapy (fluconazole, 200 mg once daily by mouth) while the rest of the evaluation was being completed. Figure 1(a). Erosive hypertrophic tongue plaque. Figure (b) ,. Erosive patch on the buccal mucosa. As part of the evaluation of the ptosis, a myasthenia gravis antibody panel was performed. It revealed the following abnormalities: striated muscle antibody at 1 : 480 (reference range, <1 : 60), acetylcholine receptor binding antibody at 6.33 nmol/L (reference range, ,,0.02 nmol/L), acetylcholine receptor blocking antibody at 31% (reference range, 0,25%), and acetylcholine receptor modulating antibody at 100% (reference range, 0,20%), suggesting thymoma. Treatment included pyridostigmine, 30,45 mg 3,4 times daily, to control the myasthenia symptoms, while the ill-defined neck mass was being evaluated. A mildly enlarged thyroid was noted on physical examination. Hematology panel revealed thyroid-stimulating hormone (TSH) levels in the low normal range; the thyroid microsomal antibody was normal. Chest radiography showed minor tracheal deviation, and a previous computed tomogram showed what appeared to be a 3-cm enlarged mass in the thyroid. Ultrasonographically guided thyroid biopsy did not show malignancy, but a benign mesenchymal-type tumor was found and surgical excision was planned. Intraoperatively, a thymoma of the left cervical thymic tongue was found. At 6 months' follow-up, the ptosis and oral mucosal lesions had improved significantly, although she continued topical corticosteroid therapy intermittently for minor erosive oral disease. [source] Mother to child transmission of HIV-1 in a Thai population: Role of virus characteristics and maternal humoral immune response,JOURNAL OF MEDICAL VIROLOGY, Issue 5 2009Chonticha Kittinunvorakoon Abstract The objective of this study was to investigate factors influencing mother to child transmission of HIV-1 in Thailand, where HIV-1 CRF01_AE, the major subtype in Southeast Asia, predominates. Samples from 84 HIV-1 infected, anti-retroviral treatment-naïve, non-breast feeding mothers, 28 who transmitted HIV-1 to their babies (transmitters) and 56 who did not (non-transmitters), were studied for maternal humoral immune response and virus characteristics. Maternal humoral immune response was measured by lymphocyte phenotyping; neutralizing antibodies to laboratory HIV-1 MN strain and two clinical isolates; peptide binding antibody to gp41 and V3 from strains CRF01_AE, B, and MN; autologous antibodies; and quasispecies diversity. Virus characteristics studied were viral load, co-receptor usage, and viral replication capacity. No significant difference between transmitters and non-transmitters was found for any parameter of maternal humoral immune response. However, viral load and viral replication capacity were significantly higher in transmitters versus non-transmitters and were not correlated with each other. This suggests that viral replication capacity may be a transmission factor independent of viral load, which is already well established as a risk factor for transmission of HIV-1. All except four viral isolates used the CCR5 co-receptor. This is one of few studies of vertical transmission in a population where HIV-1 CRF01_AE predominates. The data suggest that in this population the maternal humoral immune response was not important in preventing transmission at parturition, but that virus characteristics were key factors, and that viral replication capacity may contribute to birth-associated mother to child transmission of HIV-1. J. Med. Virol. 81:768,778, 2009. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||