Effect Of Individual And Combined Immunization Pathways On The Intensity Of Humoral Immune Response & Correlation Analysis Of Mucosal IgA J Chain And Secretory Tablets With IgA Nephropathy

This thesis consists of two parts.In the first part we studied effects of oral,intranasal and subcutaneous immunization alone or in combination with intravenious immunization in humoral immune responses.In the second part we studied the relations of mucosal IgA with IgA nephropathy through investigation of IgA J chain and secretory component.Part ?The mucosal immune system and systemic immune compartment respond at different sites.They work alone or in synergy to protect the body against invading antigens.When encountering antigens,B cells are stimulated to differentiate into antigen-specific antibody secreting cells and migrate to their effector sites.The antibody secreting cells induced by antigens at different sites translocate to different effector sites and express antibodies with different isotypes.In order to study effectiveness of immune responses and antibody isotypes produced after immunization through different routes,we immunized mice with keyhole limpet hemocyanin(KLH)via oral,intranasal(i.n.)or subcutaneous(s.c.)routes alone or combined with the intravenous(i.v.)route.The results showed that administering antigen intravenously could affect antibody production and formation of antibody secreting cells with different degrees.Combined oral/i.v.and i.n./i.v.immunization,but not s.c./i.v.immunization caused a great increase of IgA ASCs in the spleen.Combined oral/i.v,immunization could also enhance IgA production in serum and in the small intestine.Combined i.n./i.v.immunization could enhance IgA production in serum but not in the small intestine.In addition,combined oral/i.v.immunization also caused increase of IgG ASCs in both the spleen and bone marrow.In comparison,combined i.n./i.v.and s.c./i.v.immunization could increase IgG ASCs in the spleen but not in bone marrow.Intravenous administration of KLH in mice that had been immunized via oral,i.n.or s.c.routes caused some increase of IgM ASCs in the spleen but not in bone marrow.In conclusion,combined oral and i.v.administration of an antigen can induce fast and strong immune responses,especially for IgA,in both mucosal and systemic compartments.This part of work may help for optimal immunization routes of vaccinations to get more effective immune protection.Part ?IgA nephropathy(IgAN)has been recognized as the most common form of primary glomerulonephritis clinically.Its characteristic feature is deposition of polymeric IgAl(pIgA1)as the main immunoglobulin in glomerular mesangial area with mesangial cells proliferation,matrix increase,eventually leading to glomerular inflammatory injury.Currently,the pathogenesis of this disease is still not clear and there is no effective treatment.Persistent renal injury culminates in end-stage renal failure in 30%to 40%of patients within 20 years of diagnosis.Although people know that pIgAl in glomerular mesangial deposition is the direct cause leading to glomerular injury,there is still different opinins about the source of pIgAl.In order to investigate the mucosal IgA in IgAN patients and the origin of deposited IgA,we focus on J chain and SC,which are the components of mucosal IgA.In this study we selected saliva and serum samples from 57 IgAN patients,32 normal control subjects and 29 patients with other kidney diseases as disease controls.We used enzyme-linked immunosorbent assay(ELISA)to detect the levels of salivary IgA and J chain,and then detect their serum IgA levels.We also used western blot to detect the aberrance in salivary SC.The results showed that,the level of salivary IgA between IgAN patients and normal controls did not have significant difference(P=0.6294),the level of J chain did not have significant difference either(P=0.8153).However,more IgAN patients showed aberrant SC with lower molecular weight than normal controls(22.81%vs.6.25%).We also found that IgAN patients with aberrant SC also had lower level of salivary IgA and J chain,while their serum IgA levels were significantly higher than normal and other disease controls(P=0.0235,P=0.0015).This result suggests that there may have a substance in the saliva of IgA nephropathy patients,which reduces the molecular weight of normal SC.As a consequence,it causes disorder of mucosal IgA transport,resulting in decreased salivary IgA levels and elevated serum IgA levels.These results might provide clues for understanding the relations of mucosal IgA with development of IgAN.