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The feasibility of using serum IgM, IgA and IgG antibodies specific to Epstein-Barr virus (EBV) viral capsid antigen (VCA), as determined by immunoperoxidase assay (IPA), for the early diagnosis of mononucleosis was evaluated in 65 patients with infectious mononucleosis (IMN). Control groups consisted of 104 healthy students and 15 cytomegalovirus-infected patients. In the first serum sample obtained upon admission, IgM antibodies (titer > or = 64) to EBV VCA were found in 64 of the 65 IMN patients (98%), while EBV-VCA IgA antibodies (titer > or = 32) were found in 32 patients (49%). In those particular titers, no EBV-VCA IgM or IgA antibodies were found in any of the control sera. EBV-VCA-specific IgM antibodies were also not detected in any of the 15 patients with cytomegalovirus infection. In sera obtained from IMN patients within 10 days of the onset of symptoms, 18 of 19 (95%) were IgM seropositive. This study demonstrates that serum EBV-VCA IgM antibodies (titer > or = 64) as determined by IPA are highly specific (100%) and highly sensitive (98%) and can be of value for the early and rapid diagnosis of EBV-IMN infection.

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Herpes viruses, such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV), very often occur in the nasopharynx. A pathogenetic role of these viruses in immunoglobulin A nephropathy (IgA NP) is a challenging hypothesis, since upper respiratory tract infections are frequently and closely related in time to the acute episodes of IgA NP. However, conflicting reports have been published in this field. We compared the IgA and IgG antibody (AB) titres against cytomegalovirus (CMV) in sera of 41 IgANP patients with 80 healthy controls. The prevalence rates of CMV-IgA and CMV-IgG AB were significantly higher in patients with IgA NP than in healthy controls (CMV-IgA, titre > = 8, p < 0.001; CMV-IgG, titre > = 16, p < 0.05). There was also a significant difference in the concentration of CMV-IgA AB between IgANP patients and controls (IgA NP: 0.34 +/- 0.66, healthy controls: 0.06 +/- 0.33, mean +/- SD, p = < 0.002), but not in the concentration of CMV-IgG AB between NP patients and controls. While examining 60 patients with IgA NP and 75 healthy controls a significantly elevated prevalence rate of IgA AB against EBV capsid antigen (EBV-VCA) was also detected in the sera of IgA NP patients vs controls (titre > = 16; p < 0.05). There was no significant difference in the prevalence of IgG AB to EBV-VCA between patients with IgA NP and healthy controls, except at titre = 1024 (p < 0.05). At a follow-up, CMV-IgA persisted in 4 of 5, and EBV-VCA-IgA in 8 of 12 seropositive patients with IgA NP. We could not detect virus antigens or virus deoxyribonucleic acid (DNA) in the glomeruli of NP patients either with immunohistology using a monoclonal antibody or with the DNA in situ hybridization technique.(ABSTRACT TRUNCATED AT 250 WORDS)

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The significance of chlamydia serum IgG and IgA antibodies was studied, by immunoperoxidase assay, in 210 homosexual men at various stages of HIV infection. Cross sectional analysis of chlamydia IgG antibodies at a titer of > or = 128 indicated a significantly higher prevalence rate among AIDS patients (27.0%) as compared to asymptomatic HIV seronegatives (6.0%) (p = 0.022). The geometric mean titer (GMT) of IgG antibodies to chlamydia was also significantly higher in AIDS patients (106.4) as compared to HIV seronegatives (58.2) (p = 0.022) and persistently asymptomatic HIV seropositives (51.7) (p = 0.05). Chlamydia IgA antibodies did not differ significantly in prevalence and GMT among the various groups.

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The effect of treatment with doxycycline on serum IgG and IgA antichlamydial antibodies was evaluated in 33 women who had had acute salpingitis associated with high titers of serum IgG (> or = 1:128) and/or IgA (> or = 1:16) antichlamydial antibodies. Overall, 29 women (87.9%) remained with high titers of IgG and/or IgA antibodies. No change or insignificant change in IgG antibody titer was demonstrated in 21 women (63.6%) and in IgA antibody titer in 21 women (63.6%). Positive seroconversion or a significant increase (> or = 4-fold) in IgG antibody titer was demonstrated in eight women (24.2%) and in IgA antibody titer in six women (18.1%). Negative seroconversion or a significant decrease in IgG antibody titer was demonstrated in four women (12.1%) and in IgA antibody titer in six women (18.1%). It is concluded that in most patients who had acute salpingitis associated with pretreatment high titers of serum antichlamydial antibodies, posttreatment titers may remain high even if treatment with doxycycline results in complete resolution of clinical signs and symptoms of the disease.

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Kidney cell lines MA104 and BGM were infected with vaccinia and measles viruses respectively in the presence of 45Ca. Increased 45Ca level was detected in the virally infected cells as compared with control cells. An enhancement of 28 +/- 6% and 37 +/- 13% was shown in vaccinia and measles respectively following 5 h of infection. The effect of the calcium antagonist verapamil was studied in both vaccinia- and measles-infected cells. In one-step growth experiments, the mean inhibitory effect of 90 microM verapamil on viral yield after 13 h was 97 +/- 1% in the case of vaccinia. In the measles virus after 47 h a mean of 76 +/- 5% inhibition was detected. The suitability of verapamil as a potential antiviral agent is suggested and requires further investigation.

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In this study levels of prostaglandin E(2) (PGE(2)), tumour necrosis factor (TNF) and interleukin-1 (IL-1) alpha in medium from monocyte derived macrophages (MdM) infected with Chlamydia trachomatis (L(2)/434/Bu or K biovars). TNF and PGE(2) were found in both cases while IL-1 alpha was not detected. Both TNF and PGE(2) levels were higher in the medium of the MdM infected with K biovars. TNF reached maximum levels 24 h postinfection, and then declined, while PGE(2) levels increased continuously during the infection time up to 96 h post-infection. Addition of dexamethasone inhibited production of TNF and PGE(2). Inhibition of PGE(2) production by indomethacin resulted in increased production of TNF, while addition of PGE(2) caused partial inhibition of TNF production from infected MdM.

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We conducted a prospective randomized double blind study to determine: (1) the safety and immunogenicity of live oral tetravalent human-rhesus rotavirus reassortant vaccine in neonates; and (2) whether a second dose at the age of 6 to 8 weeks enhances the immunogenicity. Two hundred forty healthy neonates were enrolled and received vaccine (183) or placebo (57) on the second day of life. At the age of 6 to 8 weeks 133 received placebo and 88 received a second dose of vaccine. Medical events were noted within 10 days from vaccine administration in 6 of 183 (3.3%) vaccine recipients vs. 0 of 57 placebo recipients (P = 0.34) after the first dose and in 8 of 88 (9%) vs. 4 of 133 (3%) after the second dose (P = 0.069); none was severe and all were of short duration. Seroresponse of any type (detectable IgA or 4-fold increase of titer to rhesus rotavirus was 9% for the placebo, vs. 52 and 46% for those who received one and two doses of vaccine, respectively. However, neutralizing antibodies against human serotypes 1, 2 and 3 were not raised successfully in vaccinated infants when compared with placebo recipients. The same pattern was found when geometric mean titers were compared. Vaccine take was better when cord blood titers were low. At the age of 1 year the vaccinees had more often high titers for antirhesus rotavirus antibodies (> 640) than the placebo recipients (49% vs. 0%; P < 0.001). NO difference was found between the groups in neutralizing antibodies to human serotypes 1, 2 and 3 rotavirus.(ABSTRACT TRUNCATED AT 250 WORDS)

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A community oriented intervention program was initiated in 1985 in 12 rural communities in southern Israel to identify and treat women of reproductive age with markers of Chlamydia trachomatis (CT) infection. Among 860 women tested, 21 (2.4%) had CT IgG antibody titers greater than or equal to 128, or CT IgA antibody titers greater than or equal to 16, and 9 of these women had positive cultures for CT. The 21 women, as well as their male partners, received specific anti-CT treatment, and were followed up for 5 years to assess obstetric complications, and to evaluate the effectiveness of treatment. In 9 women positive cultures became negative. In 13 out of the 17 cases with sequential follow-up a four fold decrease in IgG specific antibody titers was observed. Yet, in all but two of the cases, IgA specific antibody titers remained greater than or equal to 16.

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One hundred and thirty eight subjects were examined for presence of antibodies by immunoperidose assay (IPA). The frequency of Cytomegalovirus (CMV) and Herpes Simplex Virus (HSV) antibody of 48 schizophrenic inpatients was compared to 48 inpatients with other psychosis and to 48 staff controls. No differences were found between schizophrenic and control groups.

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In an attempt to characterize the nature of symptomatic versus asymptomatic spotted fever group rickettsia (SFGR) infection, the immune response to R. conorii (boutonneuse fever) structural polypeptides was studied by Western-blot immunoassay. Sera from immunoperoxidase assay (IPA), SFGR seropositive (titre greater than or equal to 80) individuals, symptomatic and asymptomatic and from SFGR seronegative (IPA titre less than 80) individuals living in a kibbutz community in the desert region of Southern Israel were examined by immunoblot. This community suffered from a very high morbidity rate due to SFGR (21-fold higher than the national reported average). The entire community (n-326) has been followed-up since 1985, with serial serum samples being examined for specific IgG antibodies by IPA. The intensity of the immunoblot reaction correlated with specific IgG antibody titres as determined by IPA. This correlation was also observed between the decrease in the IgG titre and the strength of the antibody-antigen reaction by immunoblot over time for a given individual. IPA seropositive sera from asymptomatic as well as symptomatic spotted fever cases reacted to 8 individual polypeptides. In both cases antibodies to 22 kD, 24 kD, 26 kD, 28 kD, 30 kD, 32 kD, 34 kD, and 37 kD were found. In the IPA seronegative sera, antibodies to polypeptides in the range of 24 kD to 32 kD were not detected. The lack of detectable differences by immunoblotting between SFGR symptomatic vs, asymptomatic cases might be explained by other aspects of the immune response of each infected individual, and/or it is possible that virulent and non-virulent antigenically closely related SFGR strains infected symptomatic vs. asymptomatic individuals.

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The significance of serum IgG and IgA antibodies to cytomegalovirus (CMV) at various stages of human immune deficiency virus (HIV) infection was studied in 175 homosexual men. Sera were obtained from 123 HIV seropositives [41 asymptomatic, 29 with lymphadenopathy associated syndrome (LAS), 22 with AIDS related complex (ARC), and 31 AIDS patients], 17 HIV seroconverters, and 35 HIV asymptomatic seronegatives. The sera were tested blindly for CMV IgA and IgG antibodies using the immunoperoxidase assay (IPA) and CMV infected human embryo cells. Cross-sectional analysis of CMV IgG antibodies at a titer of greater than or equal to 20 showed 87% and 100% prevalence in the HIV seronegative groups and in the HIV seropositive groups, respectively (P less than 0.05). CMV IgG antibodies at a titer of greater than or equal to 80 were present in significantly higher proportions among the HIV seropositive subjects of the various groups as compared with the HIV seronegative homosexual men. However, in the HIV seronegatives who later seroconverted to HIV, a significantly higher prevalence of CMV antibodies (35%) was detected before HIV seroconversion, as compared with the persistently HIV seronegative subjects (14.3%) (P less than 0.05). The HIV seronegatives pre-HIV seroconversion also exhibited a significantly higher geometric mean titer (GMT) of CMV IgG antibodies (62.17 +/- 0.64) as compared with the persistently HIV seronegatives (34.0 +/- 0.6) (P = 0.03). Significantly higher GMTs of CMV IgG antibodies were detected in all the HIV seropositive groups as compared with the persistently HIV seronegative group. CMV IgG antibodies were not detected in the HIV seronegative subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

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The immune response to individual major antigens of Legionella bozemanii was studied in 67 sera from 26 inpatients with febrile disease using immunoblotting techniques. All the patients had fever of unknown origin and showed strong serological reactions to L bozemanii that cross-reacted with Rickettsia typhi, as determined by a standard indirect microimmunofluorescence assay. Sera analysed by western blotting reacted with 12-14 molecular components of L bozemanii with apparent molecular weights ranging from 14,000 to 94,000 daltons. These reactions compared well with a reference system using antisera of rabbits immunised with the same strain of Legionella. The three major cross-reactive components of R typhi were polypeptide antigens of 94,000, 67,000 and 43,000 daltons. It is concluded that western blotting can help in the differential diagnosis of patients with fever of unknown origin whose sera cross-react to L bozemanii and R typhi.

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Viral cofactors may be important in the pathogenesis of HIV infection and the development of AIDS, but their role is still imperfectly understood. Sequential serological studies were performed in a cohort of 100 homosexual men and 70 matched healthy controls over a mean period of 4 years. Of the patients, 18 were found to be HIV+ on admission to the study and 15 seroconverted to HIV+ during the follow up (seroconversion group). Serum antibodies of both IgG and IgA isotypes against Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were determined. IgG antibodies indicate past infection, while a marked increase in IgG titre or a positive IgA titre were taken to indicate active infection or reactivated latent infection. EBV and CMV infections were about two to four times more prevalent in the homosexual men both HIV- and HIV+, compared with controls. Active infections were increased in the homosexual men and particularly in the HIV+ patients. The seroconversion group revealed activation of both EBV and CMV following HIV infection. When the antibody profile of seroconverting patients at the time preceding seroconversion was compared with a matched group of 39 homosexual men who remained HIV-, no change was found in CMV antibodies, but four out of 15 (26.6%) of the patients had high titres of anti-EBV IgA preceding seroconversion, as compared with only one out of 39 (2.6%) of HIV- homosexual men (P less than 0.05). This suggests a role for EBV reactivation in the pathogenesis of HIV infection in some patients.

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Occurrence and significance of specific IgA and IgM to cytomegalovirus (CMV) in recurrent CMV infection was evaluated in 21 allogeneic T lymphocyte-depleted bone marrow transplantation (BMT) recipients who had been previously CMV seropositive. Of 17 patients with CMV infection, viruria was detected in 94%, CMV-specific IgA in 88% and IgM in 76%, and a fourfold rise in IgG in 65%. The median time between BMT and detection of viruria was 69 days, of IgA 70, of IgM 62, and of IgG 88 days. The IgM and IgA responses lasted for 14 and 30 days (median time), whereas high IgG titers persisted. Twelve patients developed CMV disease; in these the appearance of viruria, IgA, and IgM preceded the rise of IgG (P less than .02). CMV-specific IgA and IgM are valuable diagnostic tools in BMT recipients with recurrent CMV infection.

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IgA nephropathy, assumed to be a form of chronic immune complex glomerulonephritis, has sometimes been associated with various autoimmune diseases and autoimmune phenomena including autoantibody production. The present study was aimed at thoroughly investigating the frequency of autoantibodies against five common nuclear autoantigens in 59 patients with IgA nephropathy and in 48 patients with other immune complex glomerulonephritides (24 patients with membranous and 24 with mesangio-capillary glomerulonephritis) and in 30 healthy controls. The incidence of raised autoantibody titres (greater than or equal to 2 SD of the average of controls) in IgA NP was not found to be significantly different from the incidence of other immune complex glomerulonephritis groups. In none of the subjects was a titer above 3 SD of the average of controls found. Although IgA NP is thought to be an immune mediated disease, on the basis of our study it is not associated with a statistically significant incidence of raised antinuclear antibodies.

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In vitro models of Chlamydia trachomatis inhibition by cytokines, human-monocyte derived macrophages (HMDM) and human polymorphonuclear leukocytes (HPMN) are discussed in an attempt to delineate the molecular basis of parasite-host cell interplay in persistent and chronic chlamydial infection. Interferon gamma (IFN) has been found to reversibly inhibit chlamydial growth at an early stage in the replicative cycle, while tumor necrosis factor (TNF) has a more profound effect on chlamydial growth resulting in production of aberrant reticulate bodies and enhancement of production of prostaglandin E2 (PGE2). Chlamydia trachomatis (serovar L2) replicate in HMDM while serovar K has been found to be restricted in these cells. Chlamydiae are killed by HPMN but the cell walls persist undegraded, inducing production of oxygen radicals which can be demonstrated to induce DNA strand scissions in HeLa target cells. Evidence is accumulating that chlamydia specific serum IgA antibodies may serve as a noninvasive serological marker for diagnosis of a number of acute and persistent Chlamydia trachomatis infections.

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The point prevalence of IgG and IgA antibodies to Chlamydia was analyzed in serum and follicular fluid in 63 patients undergoing in vitro fertilisation (IVF) in comparison to sera of 298 healthy women by the single serovar (L2) inclusion immunoperoxidase assay (IPA). The presence of specific IgG and IgA to Chlamydia in follicular fluid was demonstrated. No statistical association was found between the presence of specific Chlamydia IgG and IgA in serum and follicular fluid to oocyte fertilization. The positive predictive value for mechanical infertility of Chlamydia IgG at titers of greater than or equal to 128 and IgA titers at greater than or equal to 16 was 91 and 92%, respectively, in this high-risk group for mechanical infertility. Multiple regression analysis singled out Chlamydia IgG levels as a major contributor to the variance between the groups of infertile patients.

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Development of Chlamydia trachomatis (L2/434/Bu) in HEp-2 cells was inhibited by treatment of the cells with recombinant human alpha tumor necrosis factor (TNF). In the infected cultures that were treated with TNF, high concentrations of prostaglandin E2(PGE2) were detected, exceeding by far the concentrations found in TNF-treated but uninfected cells or in infected cells that were not treated with TNF. PGE2 levels increased gradually for 2 days after infection. Raising the tryptophan concentration in the culture medium, which reversed the inhibition of chlamydial replication by TNF, also blocked the increase in PGE2 formation. However, neutralizing antibodies to beta interferon, which also interfered with the antichlamydial effect of TNF, did not decrease PGE2 formation. Excessive formation of PGE2 by cells infected with chlamydiae and treated by TNF might be related to some of the complications associated with chlamydial infection.

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Immunoperoxidase assay was used for the determination of serum-specific anti-leishmanial IgG antibodies in 65 patients with cutaneous leishmaniasis (CL), in 5 with visceral leishmaniasis (VL) and in 84 controls. A significant difference was observed between CL and VL sera and the control sera when either Leishmania major, L. donovani or L. aethiopica intact promastigotes were used as antigens. CL patients showed similar activity against L. major and L. donovani antigen (titers 4-64 and less than 2-64 respectively), whereas VL patients showed a higher activity with the homologous antigen L. donovani (titers 128-2,048). A high and significant correlation was demonstrated between immunoperoxidase assay, immunofluorescent assay and radioimmunoassay. No cross-reactivity was found with sera from malaria patients.

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