Robert S. Desowitz

The detection of antibodies in human and animal filariases by counterimmunioelectrophoresis with Dirofilaria immitis antigens

Counterimmunoelectrophoresis revealed the presence of precipitin antibody in all of 6 dogs and the 1 cat infected with Dirofilaria immitis and in the serum of 17 of 24 individuals living in a setting of hyperendemic subperiodic bancroftian filariasis. Antigens used in the test were prepared from microfilariae and adult male D. immitis. Some humans and animals had antibodies to both antigens while others had antibodies against microfilariae or adult worms only. The presence of soluble circulating antigen was detected in the sera of two dogs with high microfilaraemias.

The sites of deep vascular schizogony in Plasmodium coatneyi malaria

Abstract 3 rhesus monkeys were experimentally infected with P. coatneyi. At the time of maximal schizogonic development they were killed, and blood films, tissue crushes and sections made to locate the sites of deep vascular schizogony. The major site of schizont concentration was in the capillaries of the ventricular myocardium, but schizonts were also present in the small vessels of the liver, lung, and spleen, though not to the same extent as in the myocardium.

Plasmodium berghei: immunogenic enhancement of antigen by adjuvant addition

Abstract Vaccines consisting of soluble Plasmodium berghei antigen in conjunction with a variety of adjuvants were injected into weanling white rats. Protective immunity, as evidenced by a lower mortality rate, reduced parasitemia and shortened course of infection, was induced by antigen in combination with the following adjuvants: saponin, hexylamine, Bordetella pertussis vaccine, levamisole, and polyinosinic-polycytidylic acid (poly I:C). Soluble antigen alone or combined with Freunds complete adjuvant, bacterial cndotoxin, vitamin A, polyadenylic-polyuredelic acid (poly A:U) failed to induce any significant degree of protective immunity.

Plasmodium berghei: Enhanced Protective Immunity after Vaccination of White Rats Born of Immune Mothers

Young white rats born of immune mothers had a significantly higher level of immunity to Plasmodium berghei after immunization with a nonliving antigen than either unvaccinated littermates or vaccinated rats born of normal nonimmune mothers.

Some factors influencing the induction, maintenance and degree of maternally transmitted protective immunity to malaria (Plasmodium berghei).

Abstract A primary infection of the mother rat, induced at the time of mating, promoted a high level of immunity to P. berghei in the progeny. The level of protection diminished markedly when the interval between the time of infection and mating was 2 months or longer. However, some protective immunity was noted in the progeny whose mothers had been infected for as long a period as 9 months. When mothers who had been infected 2 and 4 months previously were rechallenged with infected erythrocytes at the time of mating an enhanced level of maternally derived protective immunity was present in the progeny. Infected and non-infected adult female rats were inoculated with a non-living P. berghei antigen and infected erythrocytes. The level of protective immunity conferred upon the progeny of these animals was compared. The ascending order of protection was as follows: in progeny from (1) non-infected mothers given non-living antigen at time of mating, (2) mothers infected 2 months prior to mating, (3) mothers given an infective inoculum 2 months prior to mating and inoculated with non-living antigen at time of mating, (4) mothers given an infective inoculum 2 months prior to mating and rechallenged with parasitized erythrocytes at time of mating.

Plasmodium berghei: Renal function and pathology in mice☆

Abstract Albino mice infected with Plasmodium berghei were studied sequentially for changes in blood urea nitrogen (BUN), percentage excretion of phenolsulfonephthalein (PSP), renal histopathology, parasitemia, and hematocrit. Anemia accompanied by hemoglobinuria and a rapidly rising parasitemia were observed on day 4. Renal function and pathology were normal at this time. By day 7 the hematocrit fell to a mean of 20 vol%, the BUN increased and the percentage excretion of PSP decreased. The BUN and PSP excretion became progressively more abnormal on subsequent days. In individual mice there was an inverse relationship between PSP excretion and BUN. During the periods of abnormal renal function, the pathologic abnormality consisted of a bloodless cortex and congested medullary vessels. No casts were present in the tubules. In some kidneys interstitual edema was present. There was no correlation between the pathologic changes in individual mice and the functional abnormalities. Possible interpretations of these data are discussed.