generation-recombinant-human-igg-monoclonal-antibodies-from

Generation of Recombinant Human IgG Monoclonal Antibodies from Immortalized Sorted B Cells

Finding new methods for generating human monoclonal antibodies is an active research field that is important for both basic and applied sciences, ...

Maastricht University

HIV-1 displays extensive genetic diversity globally which poses challenge in designing a suitable antigen/immunogen to provoke desired protective immune response in host. HIV-1 mediated pathogenesis is complex and involves host genes, virus genes and other factors. A number of genetic subtypes have been identified based on sequence variations, largely in envelope region. Different genetic subtypes display variation in amino acid sequences with increasing incidence of subtype B, C, D and mosaic recombinants in India. They can potentially alter the functions of several proteins like Rev, Tat ,Vpr, Vif etc and thereby, influence HIV-1 mediated pathogenesis. Recent study has shown that LTR promoter region exhibits novel mosaic structures with segments from B/C Myanmar and India. This indicates rapid evolving nature of HIV-1 and causing epidemics due to existence of multiple subtypes in Indian region. These multiple subtypes show significant differences in various functions (gene activation, cell cycle arrest, RNA binding activities) compared to prototype subtype B genes. These differences may help in better understanding of unique features of HIV-1 epidemic in India.

Global HIV-1 molecular epidemiology with special reference to genetic analysis of HIV-1 subtypes circulating in North India: functional and pathogenic implications of genetic variation.

Osmoregulation and the human mycobiome.

Bortezomib is a potent inhibitor of proteasomes currently used to eliminate malignant plasma cells in multiple myeloma patients. It is also effective in depleting both alloreactive plasma cells in acute Ab-mediated transplant rejection and their autoreactive counterparts in animal models of lupus and myasthenia gravis (MG). In this study, we demonstrate that bortezomib at 10 nM or higher concentrations killed long-lived plasma cells in cultured thymus cells from nine early-onset MG patients and consistently halted their spontaneous production not only of autoantibodies against the acetylcholine receptor but also of total IgG. Surprisingly, lenalidomide and dexamethasone had little effect on plasma cells. After bortezomib treatment, they showed ultrastructural changes characteristic of endoplasmic reticulum stress after 8 h and were no longer detectable at 24 h. Bortezomib therefore appears promising for treating MG and possibly other Ab-mediated autoimmune or allergic disorders, especially when given in short courses at modest doses before the standard immunosuppressive drugs have taken effect.

Proteasome inhibition with bortezomib depletes plasma cells and specific autoantibody production in primary thymic cell cultures from early-onset myasthenia gravis patients.

The role of Th17 cells in the pathogenesis of autoantibody-mediated diseases is unclear. Here, we assessed the contribution of Th17 cells to the pathogenesis of experimental autoimmune myasthenia gravis (EAMG), which is induced by repetitive immunizations with Torpedo californica acetylcholine receptor (tAChR). We show that a significant fraction of tAChR-specific CD4(+) T cells is producing IL-17. IL-17(ko) mice developed fewer or no EAMG symptoms, although the frequencies of tAChR-specific CD4(+) T cells secreting IL-2, IFN-γ, or IL-21, and the percentage of FoxP3(+) Treg cells were similar to WT mice. Even though the total anti-tAChR antibody levels were equal, the complement fixating IgG2b subtype was reduced in IL-17(ko) as compared to WT mice. Most importantly, pathogenic anti-murine AChR antibodies were significantly lower in IL-17(ko) mice. Furthermore, we confirmed the role of Th17 cells in EAMG pathogenesis by the reconstitution of TCR β/δ(ko) mice with WT or IL-17(ko) CD4(+) T cells. In conclusion, we show that the level of IgG2b and the loss of B-cell tolerance, which results in pathogenic anti-murine AChR-specific antibodies, are dependent on IL-17 production by CD4(+) T cells. Thus, we describe here for the first time how Th17 cells are involved in the induction of classical antibody-mediated autoimmunity.

IL-17-producing CD4(+) T cells contribute to the loss of B-cell tolerance in experimental autoimmune myasthenia gravis.

Deal watch: Panning for gold: sourcing pharmaceutical innovation.

Breed-wise standard electrocardiographic values in dogs have been reported as there is variation in body and chest conformation, which limits the application of data of one breed for other breed. Labrador retrievers being originated from hunting dogs, their electrocardiogram (ECG) values might be different from standard normal range of other dog breeds. So, the purpose of the present study was to determine the standard ECG of Labrador retrievers and to check effect of body weight, gender and breed upon different ECG parameters. Six-lead ECGs, three bipolar standard limb leads (I, II and III) and three augmented unipolar limb leads (aVR, aVL and aVF), were taken from 24 Labrador retrievers positioned in right lateral recumbency without any chemical restraint. Amplitude and duration of P wave and QRS complex, PR interval, QT interval and mean electrical axis and heart rate were measured in each recording. Non-significant effect of gender and body weight was seen on all the ECG waves. Deep Q waves in Leads I, II and aVF and variation in relation to QRS pattern were noted. It was concluded that retrievers had a specific shape of QRS complex which must be considered when evaluating a patient suspected of having cardiac disease. However, amplitude and durations of different ECG waves in all the six leads were statistically not affected by gender or body weight.

Article	Year
Global HIV-1 molecular epidemiology with special reference to genetic analysis of HIV-1 subtypes circulating in North India: functional and pathogenic implications of genetic variation. Indian journal of experimental biology\| PubMed ID: 19634706	2009
Osmoregulation and the human mycobiome. Frontiers in microbiology\| PubMed ID: 24860554	2014
Proteasome inhibition with bortezomib depletes plasma cells and specific autoantibody production in primary thymic cell cultures from early-onset myasthenia gravis patients. Journal of immunology (Baltimore, Md. : 1950)\| PubMed ID: 24973445	2014
IL-17-producing CD4(+) T cells contribute to the loss of B-cell tolerance in experimental autoimmune myasthenia gravis. European journal of immunology\| PubMed ID: 25676041	2015
Deal watch: Panning for gold: sourcing pharmaceutical innovation. Nature reviews. Drug discovery\| PubMed ID: 26000724	2015
Reference values of six-limb-lead electrocardiogram in conscious Labrador retriever dogs. Pakistan journal of biological sciences : PJBS\| PubMed ID: 26031002	2014

Abhishek Saxena

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