Serologic response to BK Virus following human infection with SV40.

A small group of human volunteers given live SV40 virus, and who sero-converted to SV40, did not develop any heterologous antibody response to BK virus, even when BK antibody was demonstrated in preinfection sera. SV40 infection does not appear to contribute significantly to the patterns of BK antibody seen in human populations.     

Pox infection in white rats.

2 pox outbreaks among white rats in a breeding colony are described. The infection occurred in 3 different forms: pulmonary, dermal and mixed. Apparently healthy animals appeared to be virus carriers. The virus isolated belonged to the genus Orthopoxvirus of Poxviridae family, and was very close to cowpox virus. It differed from reference strains of cowpox virus in having a lower ceiling temperature and a higher pathogenicity for white rats.     

Serologic diagnostics of Legionella infection

Technical approaches to construction of preparations for serologic diagnostics of Legionella infection were presented in the article; antigenic- and immunoglobulin-based diagnostic kits with known characteristics were developed. Immunogenic properties of protein and lypopolysaccharide antigens, which have diagnostic value, were studied; similarity of protein antigens from 7 serogroups of L. pneumophila was demonstrated. Soluble antigen with known composition was obtained and used for the development of antigen-based polymeric kit for diagnostics of Legionella infection. On the basis of hyperimmune sera, immunoglobulin-based polymeric diagnostic kit and array of coagglutinating diagnostic kits for the mentioned 7 serogroups were developed. Antigen-based polymeric diagnostic kit was recommended for licensure.     

Serologic response of Rio Grande wild turkeys to experimental infections of Mycoplasma gallisepticum

The serologic response of Rio Grande wild turkeys (Meleagris gallopavo intermedia) to Mycoplasma gallisepticum (MG) was determined. Free-ranging turkeys were caught in southern Texas, shipped to the University of Wisconsin, Madison, and housed in isolation facilities. Fourteen birds were exposed to MG, by intratracheal and intranasal inoculation. Eight birds received sterile broth only. Two wk prior to the end of the experiment, MG exposed turkeys were stressed by challenge with a serologically unrelated mycoplasma. Serum from all exposed birds reacted positively for MG antibody by the rapid plate agglutination (RPA) procedure within 2 mo postexposure (PE) and all but one remained positive for 14 mo PE. Less than one half of the exposed birds developed positive MG antibody titers detectable by the hemagglutination inhibition (HI) test within 2 mo PE, and by 10 mo PE, none had positive titers. Antibody was detected by the HI test in two of 11 infected turkeys, 14 mo PE, and titers increased significantly within 2 wk. MG was isolated from tracheal swabs from two infected birds 2 mo PE, but attempts thereafter failed. However, at the termination of the experiment 15 mo later, MG was isolated from lung tissue of three of 11 exposed turkeys and from a blood clot found in the lower trachea of one bird.     

Preliminary study on haemocyte response to white spot syndrome virus infection in black tiger shrimp Penaeus monodon

White spot syndrome virus (WSSV) has been a major cause of shrimp mortality in aquaculture in the past decade. In contrast to extensive studies on the morphology and genome structure of the virus, little work has been done on the defence reaction of the host after WSSV infection. Therefore, we examined the haemocyte response to experimental WSSV infection in the black tiger shrimp Penaeus monodon. Haemolymph sampling and histology showed a significant decline in free, circulating haemocytes after WSSV infection. A combination of in situ hybridisation with a specific DNA probe for WSSV and immuno-histochemistry with a specific antibody against haemocyte granules in tissue sections indicated that haemocytes left the circulation and migrated to tissues where many virus-infected cells were present. However, no subsequent haemocyte response to the virus-infected cells was detected. The number of granular cells decreased in the haematopoietic tissue of infected shrimp. In addition, a fibrous-like immuno-reactive layer appears in the outer stromal matrix of tubule walls in the lymphoid organ of infected shrimp. The role of haemocytes in shrimp defence after viral infection is discussed.     

Serologic pattern of meningococci in a focus of infection]

The authors present the results of typing of meningococci (isolated from the patients and carriers) by the sera of serological groups A, B, C, D, X, Y, and Z made at the Leningrad Institute of Vaccine and Sera. The causative agents of serological group A were most frequently isolated from the patients with the generalized forms of meningococcus infection. The percentage of detection of meningococci of serological group A was the greatest in the patients and much less in the carriers in and outside the foci of this infection. Many dissociated cultures were revealed among the strains isolated from the carriers. Sera of the Leningrad Institute of Vaccine and Sera have permitted typing of meningococci cultures belonging to various serological groups in accordance with the international classification.     

Peripheral blood white cell responses during Angiostrongylus cantonensis infection in rats

Yono W. K. and Dobson C. 1984. Peripheral blood white cell responses during Angiostrongylus cantonensis infections in rats. Interntional Journal for Parasitology14: 207–211. Changes in white blood cell (WBC) populations and their proliferative responses to phytohaemagglutinin (PHA) and parasite antigens in vitro were studied in rats given one to three concurrent infections with Angiostrongylus cantonensis. WBC counts were elevated following infection; these changes were augmented following each successive reinfection. The WBC response could be partitioned into variations in the numbers of four major cell types. There was a loss of lymphocytes from the circulation after infection or reinfection followed by an increase in circulating lymphocytes when the parasite migrated to the lungs and matured. An eosinophilia was observed in all rats immediately after infection which was enhanced successively after each reinfection. The monocyte populations increased in a similar, but less obvious manner, to the eosinophil leucocytes. Neutrophil leucocytes increased after infection, but the numbers declined after reinfection. All rats given one to three infections showed a neutrophilia late in the experiment. A reversal in the neutrophil leucocyte-lymphocyte ratio was observed after each infection. A peak response in the proliferation of peripheral blood lymphocytes in vitro to PHA preceded and exceeded that stimulated by A. cantonensis antigen. These responses were interpreted as the dissemination of uncommitted thymus-dependent lymphocytes involved in the induction of antigen sensitized memory cells released following the protective immune reaction. The degree of lymphocyte responsiveness to mitogens correlated with the numbers of these cells circulating at each time interval. The relationships between in vitro lymphocyte responses and protective immunity in the rat against A. cantonensis are discussed.     

Serologic evidence of hantavirus infection in sigmodontine rodents in Mexico

Antibodies to hantaviruses in two species of sigmodontine rodents (Peromyscus maniculatus and Reithrodontomys sumichrasti) collected in central Mexico are reported. Peromyscus maniculatus, a common species throughout much of Mexico, is the reservoir of Sin Nombre virus (SNV), the etiologic agent of the great majority of cases of hantavirus pulmonary syndrome (HPS) in North America. Although the identity of the virus detected in P. maniculatus in Mexico could not be determined by these serologic results, our findings suggest that SNV may occur throughout the range of P. maniculatus in North America. If true, the failure to identify HPS in Mexico is not due to the absence of pathogenic hantaviruses in Mexico.