Serological investigations on ribitol-containing lipopolysaccharides from Proteus mirabilis.

Lipopolysaccharides containing or noncontaining ribitol derived from several Proteus mirabilis strains were studied using passive hemagglutination, hemagglutination-inhibition and semi-quantitative precipitin tests. The results indicate that ribitol plays a role in the serological specificity of the respective lipopolysaccharides.     

Serological investigations in 15 cases of bird fanciers disease.

Serological studies in 15 patients with bird fanciers disease are reported. Quantitative analysis of serum proteins showed elevation of IgG in almost every case. High IgE was observed in three patients with isolated asthmatic reactions. In four patients alpha1-antitrypsin was transiently diminished. Two of these had heterozygous deficiency of this protein (genotype MS and MZ). Precipitins against avian sera and avian droppings were found in all patients, but also in some exposed and nonexposed controls. Cross-reactions to avian antigens from different species were observed quite regularly in patients but not in controls. One case is presented suggesting that these cross-reactions may be of clinical importance. Precipitins against other inhaled antigens such as Aspergillus fumigatus, cereals or Micropolyspora faeni were observed significantly more frequently in patients than in controls. These precipitins showed no cross-reactions with those against avian antigens.     

Distribution of IgG subclasses in antimonial unresponsive Indian kala-azar patients

Sodium antimony gluconate (SAG) is the mainstay of treatment for visceral leishmaniasis (VL) or kala-azar. In view of the increasing incidence of refractoriness to SAG in India, we compared the levels of parasite-specific IgG and IgG subclasses in 20 longitudinally followed up kala-azar patients. In both SAG-responsive (n = 10) and unresponsive patients (n = 10), the levels of total IgG, IgG1, IgG2, IgG3 and IgG4 were increased, the rank order being IgG1 > IgG2 > IgG3 = IgG4. Following treatment, a significant decrease in total IgG and the four subclasses occurred in the SAG-responsive group, whereas in the SAG-unresponsive group these levels were unchanged or slightly increased. Therefore, monitoring of IgG1 and IgG2 levels in Indian kala-azar patients is a good serologic alternative to monitoring the disease status.     

Cell-mediated immune response in Indian kala-azar and post-kala-azar dermal leishmaniasis

Cell-mediated immune (CMI) response in 16 Indian kala-azar (KA) and 12 post-kala-azar dermal leishmaniasis (PKADL) patients was studied in detail by in vitro lymphocyte transformation experiments and by in vivo skin testing. Peripheral blood lymphocytes of active KA patients failed to be stimulated by leishmania antigen. On the other hand, lymphocytes from a majority of the active KA patients could be stimulated by phytohemagglutinin. Active KA patients also failed to show delayed type hypersensitivity reaction to leishmanin, although 72% of them showed delayed type hypersensitivity to a purified protein derivative of tuberculin. Longitudinal studies indicated that antigen-specific CMI response usually appeared in treated KA patients after 12 to 20 weeks of antileishmanial drug therapy, although individual variations were noted. CMI response in PKADL patients was variable as about two-thirds of them showed positive sensitization to leishmania antigen in either in vivo or in vitro tests. Usually, patients with newly acquired PKADL exhibited better CMI response than those with chronic PKADL. However, lymphocytes from all of these patients could be stimulated normally by phytohemagglutinin. Results presented in this study show an impairment of CMI response in active KA which appears to be more specific to leishmania than generalized in nature. Moreover, restoration of specific T-cell responsiveness was aided by antileishmanial drug therapy which resulted in the reduction of antigenic load by parasite destruction and a concomitant decrease in circulating antibody levels, particularly that of the immunoglobulin G class. We suggest that the protection afforded by specific CMI response against Leishmania donovani infection may not be absolute and probably depends on other host-related factors leading to parasite destruction and patient recovery.     

Serological and molecular typing in platelet alloantibody investigations

Alloimmunization against platelet antigens causes complications in transfusion settings as platelet transfusion refractoriness and post‐transfusion purpura, as well as in pregnancy, causing fetal/neonatal alloimmune thrombocytopenia. Strategies for the laboratory investigations depend on a repertoire of serological and molecular assays and are often dependent on timing and objective. Technical improvements have led to a number of sophisticated methods for alloantigen typing and alloantibody identifications during the last decade; however, some traditional methods are still beneficial. The laboratory investigations should ensure that the causative antibody specificities are identified as soon as possible to support the correct diagnosis and guide the selection of compatible platelets if needed.     

Evaluation of PCR for diagnosis of Indian kala-azar and assessment of cure

This study was done to evaluate PCR with Ld1 primers for the diagnosis of Indian visceral leishmaniasis (VL) and to assess its role in prediction of the disease outcome. The PCR assay was performed with DNA isolated from the peripheral blood of parasitologically confirmed cases of VL before the initiation of treatment, just after the end of treatment, and at 3 and 6 months of follow-up. The pretreatment PCR result was positive for 100 of 101 patients (sensitivity, 99%; confidence interval [CI], 94 to 100%). None of the 150 negative controls tested were PCR positive (specificity, 100%; CI, 96.8 to 100%). Of 60 patients who were treated at our center, 51 (85%; CI, 73 to 93%) became negative immediately after treatment and continued to be negative at 3 and 6 months of follow-up. At the 3-month follow-up, two of the remaining nine patients were PCR positive, making 58 (96.7%; CI, 87 to 100%) patients PCR negative. At the 6-month follow-up, all patients became PCR negative. One patient who was PCR negative immediately after the end of treatment relapsed 11 months later. This limited prospective study with VL patients suggests that the PCR assay is a highly sensitive and specific (99% and 100%, respectively) tool for the diagnosis of VL. In the majority of patients, it can identify a successful disease outcome; however, its translation into the field setting remains a major challenge.     

Serological investigations in children with colonized Spitz-Holter valves

It has been found that children with hydrocephalus, whose Spitz-Holter valves are colonized with Staph. albus, have an antibody to this organism in their serum. Children without colonized shunts have little or no such antibody. A test for this antibody is described, and its use in such cases is discussed.     

Serological and biochemical investigations among five endogamous groups of Delhi, India.

Phenotype and gene frequencies for four blood group systems (ABO, MN, Rh and P) and haptoglobin among five endogamous groups of Delhi, India, are reported. All the systems are polymorphic in all the population groups. The average heterozygosity per locus in high (in the range 48-52 per cent) for all the groups. The extent of genic variability among the groups in terms of net codon differences per locus has been studied; the heterogeneity within the groups is large as compared to the between-group heterogeneity. There is no definite clustering of the of the groups with respect to their biological rank.     

Immunoblot analysis of the antibody response to antigens of Leishmania donovani in Indian kala-azar

When infected with Leishmania donovani, patients develop specific antibodies that constitute the basis of serodiagnosis. Using immunoblot analysis, we examined the antibody response to antigens of L. donovani in 35 kala-azar (KA) patients and 67 controls. Sera from KA patients recognised numerous antigens with molecular weights ranging from 14-110 kDa. Antigens of 40 kDa, 55 kDa, 65 kDa, 70 kDa and 82 kDa were recognised most frequently. All KA patients produce an antibody response to one or more of these antigens. The majority (83%) of KA cases recognised at least four of these five parasite antigens. The 70 kDa antigen showed the greatest sensitivity for Indian KA, and produced a positive reaction in 94% of patients. This antigen gave 10% false-positive reactions in controls comprising patients with related diseases (i.e. tuberculosis, leprosy and malaria) and in healthy controls. Data indicated that the 70 kDa antigen may include a member of the heat shock protein 70 family. Studies with four clinical isolates of L. donovani showed that the 70 kDa component was expressed in all the strains examined. Immunoblot assay (Western blotting) provided a sensitive diagnostic test for KA patients, and identified the 70 kDa parasite antigen that is promising as a potential target antigen for the development of less complex serodiagnostic assays for KA.     

Serological, clinical and epidemiologic analysis of 53 cases of kala-azar in the Arab Republic of Yemen

The visceral leishmaniasis (Kala-Azar) is present in Republic Arab of Yemen. On 53 cases diagnosed during 21 months in Taez Republican Hospital the disease is affecting essentially children (55 under five years old) with predominant focus in the area of Charaab and Qobeita. Serology using passive hemagglutination is helpful for the diagnosis when the rate is higher or equal to 1/64e. The problem of wrong positive reaction in cases of lymphoblastic leukemia and Hodgkin is noticed.     

Subpopulations of T lymphocytes in the peripheral blood and lymph nodes of Indian kala-azar patients

Distribution of T cells in the peripheral blood and lymph nodes of Indian kala-azar (KA) patients was studied by using appropriate phenotypic markers for CD2⁺, CD4⁺ and CD8⁺ cells. Significant reduction in the CD2⁺, CD4⁺ cell numbers as well as CD4⁺/CD8⁺ cell ratio was noted in the peripheral blood of active KA cases. Such alteration in the T cell population appeared to be a manifestation of the disease process as it showed a tendency to return close to normalcy several months after successful chemotherapy. Histopathological studies of KA patients with lymphadenopathy demonstrated gradual destruction of lymph node follicular architecture which correlated well with the severity and duration of illness. Massive infiltration of CD2⁺ cells in the cortical region of lymph node was evident. The observed preponderance of CD4⁺ cells over CD8⁺ ones in these infiltrates was in sharp contrast to the distribution pattern of these cells in the periphery. Significance of these findings is discussed in relation to the current concepts on the immunology of leishmaniasis and related diseases. Received: 20 May 1996     

Tissue distribution of the T cell activation antigen Ta1. Serological, immunohistochemical and biochemical investigations.

The recently described Ta1 antigen is expressed by activated T cells in vitro and in vivo, as observed in patients with certain immune-mediated diseases, such as multiple sclerosis. In this paper we report on the tissue distribution of the Ta1 antigen. Serological testing of human tumour cell lines and immunohistochemical analysis of human tissue sections revealed a reactivity of the anti-Ta1 antibody with normal and malignant tissues of the upper gastro-intestinal tract, the biliary tract, exocrine pancreas and kidney. SDS-PAGE analysis of immunoprecipitates from 125I-labelled cells, employing the anti-Ta1 antibody, yielded a 113-115 kD band from three serologically Ta1 positive tumour cell lines, from a serologically Ta1 negative human EBV-transformed B lymphoblastoid cell line, from peripheral blood mononuclear cells (PBMC) and, as previously described, a 105 kD band from PHA activated T cells (Fox et al., 1984). After endoglycosidase F treatment similar bands of 85 kD were precipitated from activated T cells and from tumour cell lines. It is therefore likely that very similar glycoproteins, which differ only modestly in the size of carbohydrate chains, bear the Ta1 epitope on Ta1 positive tissues.     

Characterization of immunoglobulin G and its subclass response to Indian kala-azar infection before and after chemotherapy

Serologic parameters of kala-azar were evaluated by Western blot analysis. Sera from kala-azar patients with confirmed diagnoses were screened for immunoglobulin G (IgG) and IgG subclass-specific reactivity against Leishmania donovani membrane antigen (LAg). Heterogeneous LAg-specific IgG reactivity with numerous proteins with molecular masses ranging from 18 to 190 kDa was observed. Though the individual band patterns were varied, seven polypeptides of approximately 31, 34, 51, 63, 72, 91, and 120 kDa were immunoreactive with all the sera tested from kala-azar patients. The band patterns of the immunoblots of sera from patients after treatment and clinical cure with sodium antimony gluconate revealed a decrease in the frequency of the bands. Still, recognition of the 63- and 120-kDa bands was 100%, and the 55- and 91-kDa fractions were recognized in 93% of the sera from cured individuals. Among the IgG subclasses, IgG1 reacted with the greatest number of polypeptides. The 63-kDa protein was again detected by all of the IgG subclasses of all the sera tested. Other fractions recognized by the subclasses of more than 70% of the serum samples included those of 47, 51, 55, and 78 kDa. Following treatment, 63- and 51-kDa bands were the most reactive with the IgG subclasses. LAg-associated cross-reaction with other reference human antisera revealed a mild reactivity of the 63-kDa polypeptide with some of the serum samples from leprosy, malaria, typhoid, tuberculosis, and healthy controls. Western blot analysis of LAg entrapped in liposomes, strong vaccine candidates against experimental visceral leishmaniasis, revealed a more restricted band pattern. The 63-kDa fraction revealed by all pre- and posttreatment sera showed almost negligible levels of cross-reaction with sera from patients with other diseases or from healthy controls. These observations provide insight into induced immunity during kala-azar infection for future application.     

Transplacental (passive) transmission of plague antibodies in the great gerbil. Serological investigations in plague

Summary Passive transmission of plague antibodies from immune female great gerbils to their progeny was established. A high antibody titre was revealed in all the embryos, the placenta and amniotic fluid. The antibodies were retained in the serum of the young up to the 20th day after birth (observation period).(Presented by Active Member AMN SSSR N. N. Zhukov-Verezhnikov) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 55, No. 6, pp. 88–91, June, 1963