With the development of bio-technological drugs, drug immunogenicity evaluation has become key factor of clarifying safety and efficacy of these drugs. It has become the focus to establish a stable and reliable evaluation system. Due to the advantages such as continuous real-time monitoring, surface plasmon resonance (SPR) technology has been widely used in bio-technological drugs immunogenicity assessments. Our study applied this technology to detect anti-drug antibody (ADA) of a recombinant human anti-rabies monoclonal antibody NM57 in the sera of 48 volunteers admitted in phase I clinical trials. This method could satisfy the basic requirements of detection of ADA.
Antibodies, Anti-Idiotypic ; analysis ; blood ; immunology ; Antibodies, Monoclonal ; analysis ; blood ; immunology ; Antibodies, Viral ; analysis ; blood ; immunology ; Humans ; Rabies virus ; immunology ; Recombinant Proteins ; analysis ; blood ; immunology ; Surface Plasmon Resonance

Vitiligo is a disease in which melanocytes are selectively destroyed. The disease is thought to be an autoimmune process being there are antibodies to pigment cells in the sera of patients and animals with vitiligo. In the present study, sera from vitiligo patients were examined for reactivity with the human melanoma cell line, SK-Mel-28, by Western blot analysis of solubilized membrane antigens of these cells to identify the pigment cell antigens defined by antibodies in the patients with vitiligo. Antibody reactivity to human melanoma cells (SK-Mel-28) was investigated in 14 patients with vitiligo, and 16 with normal control individuals. Antibodies to the 116-113, 60, 40 KD antigens were associated with vitiligo being present in 79%, 86%, and 43% respectively of the patients with vitiligo, but in only 6%, 38% and 6% of the normal controls. In contrast, antibodies to the 160-155, 78 and 64 KD antigens were equally common in vitiligo and in normal individuals. The results suggest that autoreactivity to pigment cells occurs more commonly in patients with vitiligo than in the normal control and high autoreactivity to pigment cells in the vitiligo sera might be an impertinent epiphemenon to destroyed pigment cell.
Antibodies, Neoplasm/*blood ; Antigens, Neoplasm/immunology ; Autoantibodies/blood ; Blotting, Western ; Human ; Melanoma/*immunology ; Vitiligo/*immunology

Adult ; Antibodies, Anticardiolipin ; blood ; Antibodies, Antiphospholipid ; blood ; Autoantibodies ; blood ; Female ; Humans ; Male ; Middle Aged ; Phosphatidic Acids ; immunology ; Phosphatidylcholines ; immunology ; Phosphatidylethanolamines ; immunology ; Phosphatidylinositols ; immunology ; Phosphatidylserines ; immunology ; Reference Values

Antibodies, Antinuclear ; blood ; Autoantibodies ; blood ; Autoimmunity ; Biomarkers ; blood ; Hepatitis C ; blood ; immunology ; Humans ; Mitochondria ; immunology ; Muscle, Smooth ; immunology ; Retrospective Studies

OBJECTIVETo investigate the characteristics and dynamic changes of serum neutralizing antibody response in patients with primary infection of dengue virus type 1 (DENV-1).

METHODSSerum samples were obtained from the same patients with primary infection of DENV-1 within 2 weeks after symptom onset in 2006 and in 2010. A group-specific DENV NS1 capture ELISA-based micro-neutralizing test (ELISA-MNT) capable of detecting neutralizing antibodies against all the 4 serotypes of DENV was used to test the neutralizing antibody titers against DENV in the serum samples. The neutralizing antibody titers against a standard strain and 2 clinically isolated strains of DENV-1 were detected in serum samples collected in 2010.

RESULTSCross-reactive neutralizing antibody response against all the 4 serotypes of DENV was found in both of the serum samples collected in 2006 and 2010, but the samples collected in 2006 showed stronger cross-reactive neutralizing antibody responses. The neutralizing antibody against DENV-2, rather than the anticipated DENV-1 antibody, had the highest titer in the samples collected in 2006, whereas the antibody against homologous DENV-1 had the highest titer in the samples obtained in 2010. The neutralizing antibody titers against the homologous DENV-1 was significantly higher in samples collected in 2010 (U=86.500, P=0.000), which also demonstrated significantly different neutralizing antibody titers against the 3 different strains of DENV-1 (Χ(2)=12.123, P=0.002).

CONCLUSIONThe production of cross-reactive neutralizing antibodies between the 4 serotypes of DENV is a characteristic of DENV infection, particularly during early infection, but only the homologous neutralizing antibody increases obviously over time. The titers of the neutralizing antibodies against different strains, even of the same serotype, may differ distinctly.

Antibodies, Neutralizing ; blood ; Antibodies, Viral ; blood ; Cross Reactions ; Dengue ; blood ; immunology ; Dengue Virus ; classification ; immunology ; Humans ; Neutralization Tests

OBJECTIVESHuman metapneumovirus (hMPV) has been identified as one of the most important viral pathogens for acute respiratory tract infections in children. This study was to observe neutralizing activity to hMPV in sera collected from children without respiratory illnesses aged 0 to 6 years and to investigate the correlation between the level of hMPV IgG antibody and neutralizing activity in the same serum.

METHODSSera of 0 to 3 years old children were collected from patients hospitalized for surgery without documented respiratory illnesses, and sera of 3 to 6 years old children were remainder of serum specimens taken for health checkup. Total number of serum specimens was 325. Ten serum samples were selected for neutralizing activity detection in every age group and the sum was 50. The neutralizing titer was assessed by microneutralization assay which had been well documented previously.

RESULTSAmong 50 serum samples, eight in which hMPV IgG antibody was proved negative by ELISA previously did not show any neutralizing activity. The remaining 42 samples, as expected, showed variable neutralizing activity. The geometric mean neutralizing titer to hMPV for all the samples was 1:129. In the age group of 0-5 months, the geometric mean titer was 1:160. In the age groups of 6-11 months, 12-23 months, 24-35 months, 3-6 years, the geometric mean titers were 1:58.9, 1:114.9, 1:172.8 and 1:160.0, respectively. The level of hMPV antibody and neutralizing activity in the same serum was significantly correlated (r = 0.668).

CONCLUSIONMost 0-6 year-old children in Chongqing area have neutralizing antibody in their serum. Whether such neutralizing activity is high enough to prevent infection with different subtypes of hMPV is unknown.

Antibodies, Neutralizing ; blood ; immunology ; Antibodies, Viral ; blood ; Child ; Child, Preschool ; China ; Enzyme-Linked Immunosorbent Assay ; Humans ; Metapneumovirus ; immunology ; Paramyxoviridae Infections ; blood ; immunology ; Pediatrics ; Respiratory Tract Infections ; immunology

Antibodies, Viral ; blood ; Humans ; SARS Virus ; immunology ; Severe Acute Respiratory Syndrome ; immunology ; T-Lymphocytes, Cytotoxic ; immunology

Immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease. It is considered that production of platelet auto-antibodies was one of the pathogenesis of ITP, first-line therapy including corticosteroid and immunoglobulin could reduce destruction of platelets by inhibiting production of auto-antibodies and blocking Fc-receptor of reticuloendothelial system, but some of the patients were refractory to first-line therapy and have persistent duration of the disease, having worse prognosis and developing into chronic/refractory ITP(C/RITP) . Platelet membrane glycoprotein like GPIIb/IIIa and GPIbα are the most common antigen targets, but first-line therapy was less effective to patients whose anti-GPIbα antibodies are positive. Further studies revealed that the way causing platelet destruction by anti-GPIIb/IIIa antibodies and anti-GPIbα antibodies are different: the former is mainly dependent to Fc-pathway, and the latter mainly cleared platelet by Fc-independent way. Results above indicated that detection of type of platelet auto-antibodies maybe potential to treatment and prognosis of ITP. This article summarizes relationship between platelet specific antibodies and the onset, clinical manifestation, treatment and prognosis of ITP.
Antibodies ; immunology ; Autoimmune Diseases ; Blood Platelets ; immunology ; Humans ; Platelet Membrane Glycoproteins ; Prognosis ; Thrombocytopenia ; immunology ; therapy

Plasmodium falciparum liver stage antigen-1 (PfLSA-1) is one of the few antigens expressed exclusively in liver stage parasites. In this study, we evaluated the antibody responses against recombinant PfLSA-1 in naturally infected individuals in Myanmar. High levels of antibody responses (70.7%) were detected in 82 serum samples from 116 infected individuals, and IgG responses to PfLSA-1 principally composed of responses of IgG1 and IgG3 subclasses. These results show that PfLSA-1 elicits effective antibody responses in individuals infected with P. falciparum, and thus it could be not only an attractive candidate protein for vaccine development, but also a useful antigen for serodiagnosis of the infection.
Animals ; Antibodies, Protozoan/*blood/immunology ; Antigens, Protozoan/*immunology ; Humans ; Immunoglobulin G/blood ; Malaria, Falciparum/blood/epidemiology/*immunology ; Myanmar/epidemiology

OBJECTIVETo investigate the prevalence of antinuclear antibodies (ANA) and anti-liver/ kidney microsomal type 1 antibodies (anti-LKM1) in patients with chronic hepatitis C (CHC)and to explore the mechanism of production of these autoantibodies.

METHODSSerum samples were collected from 360 patients with CHC (case group), 69 patients with chronic hepatitis B (CHB) and 69 patients with autoimmune hepatitis (AIH) (control group). Serum ANA and anti-LKM1 were detected by indirect immunofluorescence (HF) technique and enzyme-linked immunosorbent assay (ELISA), respectively. Multi-factor analysis was performed to explore the correlations of the production of autoantibodies with some factors such as age, sex, viral loads, HCV genotype, biochemical parameters and clinical characteristics.

RESULTSFifty-four (15%) of 360 patients infected with HCV were positive in autoantibodies. The prevalence of ANA and anti-LKM1 were 12.5% (45/360) and 2.5% (9/ 360), respectively. The positive rate of autoantibodies in patients with CHC was significantly higher than that in patients with CHB (15% vs 2.9%, P = 0.006), but significantly lower than that in patients with AIH (15% vs 47.9%, P < 0.001). Twenty-one (11.35%) of 185 male patients and 33 (18.86%) of 175 female patients were positive in autoantibodies, the difference in positive rate was significant (P < 0.05). HCV virus loads in the autoantibodies negative group were higher than that in the autoantibodies positive group (7.2 x 10(7) copies/L vs 1.23 x 10(7) copies/L, P < 0.05). There were not significant differences in age and genotype between the autoantibody positive group and the autoantibody negative group. The serum biochemical parameters of the autoantibody positive group were similar to those of the autoantibody negative group. The differences were not significant for the course of disease, clinical symptom, the incidence of cirrhosis between the autoantibody positive group and the autoantibody negative group. The prevalence of autoantibodies was not different for patients with or without interferon treatment (P > 0.05).

CONCLUSIONAutoantibodies related to AIH can be detected in CHC patients; interferon may not induce the production of autoantibodies; it is very likely that HCV infection induces the autoimmune reaction and the production of autoantibodies.

Adult ; Antibodies, Antinuclear ; blood ; immunology ; Autoantibodies ; blood ; immunology ; Female ; Hepatitis C, Chronic ; blood ; immunology ; virology ; Humans ; Male ; Middle Aged