Malarial Antibody Research Articles

Comments on Malarial Antibodies

Comments on Malarial Antibodies

THE ANTIBODY RESPONSE IN VOLUNTEERS WITH CYNOMOLGI MALARIA INFECTIONS.

SummaryThe antibody response to the B strain (six patients) and the M strain (one patient) of Plasmodium cynomolgi was studied in volunteers with sporozoite-induced infections. In all cases malarial antibody was detected after, but not before, the initial parasitemia even throughout long prepatent periods which in one individual extended 107 days. A comparison of the antibody response in patients with short or with long prepatent periods suggests that there is great similarity in respect to the abrupt rise in serum antibody levels after the initial parasitemia and to the subsequent course of antibody production.

Production of Malarial Antibody

AT THE PRESENT TIME there is no accepted serological test which is adaptable to routine use in the investigation of the production of antibody in malarial infections. Attempts in the past to obtain specific complement-fixation and precipitation reactions with sera from patients infected with malaria have met with limited success. 1,2 The fluorescent-antibody technique has been successfully used in the specific staining of malarial parasites, 3,4 and our investigations were undertaken using the indirect method of immunofluorescence 5 to follow the course of production of antibody in normal volunteers infected by Plasmodium vivax and the simian parasite, the B strain of P cynomolgi . The suggestion that a humoral element of malarial immunity is produced in natural infections and is gamma globulin has been expressed by several investigators. 6-9 We were therefore also interested in determining whether any relationship exists between changes in serum gamma globulin and the production of

Fluorescent antibody staining as a measure of malarial antibody.

The erythrocytic forms of 3 species of human malaria parasites but not the sporozoites and oocysts of L. falcipara have been stained by the indirect method of the fluorescent antibody technic. The technic has been used to measure the circulating antibody to malaria with some success and the results so far confirm classic concepts of malarial immunity. Antibody to malaria has been demonstrated in cord blood from immune mothers.

Antibody production in human malaria as determined by the fluorescent antibody technique.

No reliable serological test has been available in the past to follow the course of antibody production in malarial infections. The indirect method of immunofluorescence was utilized in this investigation to study antibody response to sporozoite-induced Plasmodium vivax infections in two human volunteers. Malarial antibody was demonstrated approximately 3 weeks after infection, and has persisted thus far for 121 days. These preliminary results suggest that this method of serological testing is specific and provides a sensitive means of titrating antibody produced in malarial infections.

Transmission of antimalarial immunity ( Plasmodium berghei) from mother rats to their young during lactation

1. (1) This work confirms the report of Bruce-Chwatt (1954), that suckling rats, born of mothers which have been immunized against Plasmodium berghei, show a slight but definite resistance to infection with this parasite. The resistance increased during the nursing period but it was of a temporary nature, and 7 weeks after weaning it had disappeared entirely. 2. (2) Experiments, in which the litters of immune and normal animals were exchanged soon after birth, showed that transference of resistance occurred mainly, if not entirely in the milk.The effect of immune milk could be duplicated in normal suckling rats by giving them immune serum by mouth.Rats which had reached the age of 22 days when first given serum showed no resistance ; evidently malarial antibodies can no longer be absorbed through the gut at this age. 3. (3) The transitory resistance to malarial infection shown by human infants, living in hyper-endemic areas, may be due in part to a similar transference of maternal antibodies; in this case, however, the antibodies are probably transferrred in utero and not in the milk.