Risk factors for HIV seropositivity among people consulting for HIV antibody testing: a pilot surveillance study in Quebec.

The surveillance of AIDS (acquired immune deficiency syndrome) through case reporting only reflects the epidemiologic features of HIV (human immunodeficiency virus) transmission a few years earlier and not the prevalence of HIV seropositivity. HIV infection is not a notifiable condition in Quebec. We were asked by the ministère de la Santé et des Services sociaux du Québec to perform a pilot project for the surveillance of HIV seropositivity using a network of sentinel physicians. From May 15, 1988, to Sept. 30, 1989, physicians from four collaborating centres collected data on the serologic status, demographic characteristics and risk factors for 4209 patients who underwent HIV antibody testing. Of the 3899 subjects included in the study 7.9% were HIV positive. Through logistic regression analysis the following variables were found to be significantly associated with HIV seropositivity: presence of HIV-related symptoms (prevalence odds ratio [POR] 36.5), origin from an endemic area (POR 9.1), homosexuality or bisexuality (POR 8.4), intravenous drug use (POR 4.2), male sex (POR 2.8), previous HIV antibody testing (POR 2.5) and previous sexually transmitted disease (POR 1.8). Over the study period we found a large increase in HIV seroprevalence among intravenous drug users (4.2% in 1988 to 19.0% in 1989) (p = 0.02). This increase might reflect a recent change in the epidemiologic pattern of HIV transmission in Quebec. Surveillance of HIV seropositivity through a network of sentinel physicians may be a reasonable alternative to mandatory reporting.     

The influence of HIV infection on antibody responses to a two-dose regimen of influenza vaccine

We studied whether a two-dose regimen of inactivated influenza virus vaccine was more effective than a single dose in inducing protective hemagglutination-inhibition antibody responses in patients infected with human immunodeficiency virus (HIV). Participants included subjects with acquired immunodeficiency syndrome, subjects with acquired immunodeficiency syndrome-related complex, and HIV-seropositive individuals with either lymphadenopathy only or no symptoms. Control subjects were HIV-seronegative heterosexuals and HIV-seronegative homosexuals. Two doses of inactivated influenza vaccine containing 15 micrograms of the hemagglutinin of influenza A/Taiwan/1/86(H1N1), A/Leningrad/360/86(H3N2), and B/Ann Arbor/1/86 were administered intramuscularly in the deltoid region 1 month apart. The second dose of vaccine did not significantly increase the frequency or magnitude of antibody responses of either HIV-seropositive or HIV-seronegative subjects over that achieved by a single dose. The two-dose regimen induced a protective level (greater than or equal to 1:64) of hemagglutination-inhibition antibody to influenza A(H1N1) or (H3N2) virus less often in subjects with symptomatic HIV infection than in uninfected control subjects (39% vs 87% or 46% vs 97%, respectively). Our results suggest that a substantial proportion of individuals with symptomatic HIV infection might remain unprotected from influenza, even after immunization with a two-dose regimen.     

HIV antigen and antibody detection: variable responses to infection in the Edinburgh haemophiliac cohort

Sequential serum samples from 18 haemophiliac patients exposed simultaneously to human immunodeficiency virus type 1 (HIV 1) in early 1984 were tested retrospectively for serological markers of infection. Assay for total antibodies to HIV established that the time to seroconversion might be as long as 110 days after exposure to contaminated factor VIII; serum samples were also tested by Western blotting, by enzyme linked immunosorbent assay (ELISA) for specific antibodies to envelope and core proteins, and for p24 antigen by two assay systems during the two years after infection. The studies showed that five of the 12 patients for whom serum samples obtained between exposure and seroconversion were available had transient p24 antigenaemia. Although amounts of total antibody to HIV and of antibodies to envelope proteins rose continuously during the two years of the study, amounts of antibody to the core protein were variable and tended to decline in patients who became symptomatic. Two patients had persistent p24 antigenaemia that began four months after seroconversion; these patients remained asymptomatic. One patient who developed the acquired immune deficiency syndrome (AIDS) had transient antigenaemia at the time of seroconversion but failed to show any antigen for the rest of the study; progression to AIDS was accompanied by an increase in antibodies to envelope proteins. Much of the variability in the course of infection with HIV must represent the differences in the susceptibility of the patients to infection.     

Global characterization of modifications to the charge isomers of IgG antibody

Posttranslational modifications of antibody products affect their stability, charge distribution, and drug activity and are thus a critical quality attribute. The comprehensive mapping of antibody modifications and different charge isomers (CIs) is of utmost importance, but is challenging. We intended to quantitatively characterize the posttranslational modification status of CIs of antibody drugs and explore the impact of posttranslational modifications on charge heterogeneity. The CIs of antibodies were fractionated by strong cation exchange chromatography and verified by capillary isoelectric focusing-whole column imaging detection, followed by stepwise structural characterization at three levels. First, the differences between CIs were explored at the intact protein level using a top-down mass spectrometry approach; this showed differences in glycoforms and deamidation status. Second, at the peptide level, common modifications of oxidation, deamidation, and glycosylation were identified. Peptide mapping showed nonuniform deamidation and glycoform distribution among CIs. In total, 10 N-glycoforms were detected by peptide mapping. Finally, an in-depth analysis of glycan variants of CIs was performed through the detection of enriched glycopeptides. Qualitative and quantitative analyses demonstrated the dynamics of 24 N-glycoforms. The results revealed that sialic acid modification is a critical factor accounting for charge heterogeneity, which is otherwise missed in peptide mapping and intact molecular weight analyses. This study demonstrated the importance of the comprehensive analyses of antibody CIs and provides a reference method for the quality control of biopharmaceutical analysis.     

Prevalence of HIV seropositivity among patients with squamous cell carcinoma of the conjunctiva

Objective

To determine the prevalence of HIV seropositivity among patients with squamous cell carcinoma of the conjunctiva.

Methods

All patients with clinical and histopathological confirmation of squamous cell carcinoma seen during a ten year period (July 1999 to June 2009) were tested for HIV (Human Immunodeficiency Virus). The number of patients with squamous cell carcinoma of the conjunctiva who are HIV positive were counted.

Results

A total of thirty-three(33) eyes in thirty-two(32) patients were confirmed histopathologically to have conjunctival squamous cell carcinoma. Their ages ranged from 22 years to 66 years with a mean age of (38.6±11.8) years (SD). The male to female ratio was 1:1.5. Twenty four (75%) of these patients were HIV positive.

Conclusions

Squamous cell carcinoma is associated with the human immunodeficiency virus and is thus a marker for the disease in Benin City, Nigeria.     

不同方法检测红细胞血型IgG抗体的探讨

目的比较3种方法检测红细胞血型IgG抗体,为确定选用检测该抗体的方法及确定检测该抗体的最佳方案提供依据。方法采用聚凝胺法、抗球蛋白法及蛋白酶法等3种方法,分别检测116人份预处理过的O型血清（其中不含IgM抗-A及IgM抗-B）中的IgG抗A及IgG抗B,分别检测1批IgG抗D及1批IgG抗E效价的积分。结果在116人份预处理过的O型血清中,聚凝胺法、抗球蛋白法及蛋白酶法分别检出74人份、71人份及73人份血清中有IgG抗A,检出率分别为63.79%、61.21%及62.93%,三者比较差异无统计学意义（χ^2=0.172,P〉0.05）,分别检出83人份、81人份及82人份血清中有IgG抗B,检出率分别为71.55%、69.83%及70.69%,三者比较差异无统计学意义（χ^2=0.083,P〉0.05）;聚凝胺法、抗球蛋白法及蛋白酶法分别检出1批IgG抗D效价的积分为46、42、46,分别检出1批IgG抗E效价的积分为32、30、32。结论 3种方法均可用于检测红细胞血型IgG抗体,但采用单一方法检测该抗体,个别样本中的该抗体可被漏检,若采用3种方法联合应用来检测该抗体,则可防止个别样本中的该抗体被漏检,因此,采用3种方法联合应用来检测该抗体,是检测该抗体的最佳方案。