605 TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE, VOL. 72, No. 6, 1978
Mother-child relation in human schistosomiasis mansoni : skin test and cord blood reactivity to schistosomal antigens Laboratdrio
Central
PIERRE TACHON AND RADOVAN BOROJEVIC Gonpalo Murk, 121 rua Waldemar Falctlo, Salvador, 77 rue Pasteur, Lyon, France
Summary Reaction to schistosomal antigen was studied in children born to mothers infected with Schistosoma mansoni. Values of immediate (15 min) skin reactions were more elevated and values of delayed (24 h) skin reactions were significantly higher in children born to infected mothers than in children born to uninfected mothers. The macrophage migration inhibition test, done on cord blood cells, was positive to schistosomal antigen in 40 % of children born to infected mothers and negative in all children born to uninfected mothers. These results suggest prenatal sensitization to schistosomal antigen in children born to mothers infected with S. mansoni. Introduction In regions hyperendemic for schistosomiasis mansoni, where levels of infection are above 90%, severe overt disease affects 5 to 25 “,/oof the population. The distribution of severe cases is not random but involves preferentially members of a limited number of families. This familial distribution was described by KLOETZEL (1958) and confirmed recentlv in studies bv 1. C. BINA in the State of Bahia (personal communication). In a homogeneous population familial distribution of severe forms of the disease may be related to microecological, hereditary or congenital factors. Congenital modifications of the immune response to schistosomiasis have been demonstrated in several experimental systems (LEWERT & MANDLOWITZ, 1969; HANG et al., 1974) and its effect on the evolution of the disease has been shown BOROJEVIC et al., 1977). In an earlier study, we demonstrated positive delayed skin reactions to schistosomal antigen in uninfected children born to infected mothers (CAMUS et al.. 1976). The uresent studv was under taken to investigate this phenomenon in new-born children, and thus to differentiate the modifications of an immune response acquired during intrauterine life from those subsequently acquired due to lactation and contact with the local environment. Materials and Methods Population studied 35 parturients and their children, admitted to “Luiz Argollo” Maternity Hospital in SantoAntonio-de-Jesus, state of Bahia, Brazil, were studied. Tb.ev all came from the surroundine rural area, endemic for schistosomiasis mansoni. 26 mothers were infected with Schistosoma mansoni. Schistosomal infection was monitored by stool
Brazil
and Institut
Pasteur,
examination and by immunological methods, i.e. immediate skin reaction (15 min), immunofluorescence and immuno-electrophoresis (carried out on lyophilized sera in the routine diagnostic service of the Institut Pasteur in Lille, France). One stool examination revealed eggs in the faeces of 18 mothers. Repeated stool examinations, often necessary to establish the presence of a light schistosome infection, could not be done. When the immediate skin reaction and at least one serological test were positive, schistosomal infection was presumed as, in young individuals, living continuously in an endemic area, spontaneous cure would not be expected. No mothers had previously had chemotherapy against schistosomiasis. Mothers with a negative stool test and negative immunologically were used as the control group. The mothers’ ages varied from 15 to 44 years and most had had several children. All the women studied appeared in a satisfactory general state and none had overt severe schistosomiasis. All cases with infectious genital diseases were eliminated. 26 babies were born naturally and nine by caesarians. Intestinal parasites are common in this region (Ascaris, Trichuris and Ancylostoma) but no severe infection was observed in the series studied. Eight of the parturients were Negro, six white and the rest were mixed Negro, white and Indian blood, classified as “pardo”, following Brazilian standards. In vivo techniques Skin tests were done on the interior forearm of mothers and on the arm of children. Intradermal injection of 0.05 ml of commercial “Behringwerk AG” schistosomal antigen (total worm extract) was followed by injection of 0.05 ml of “Behringwerk AG” control solution at an adjacent site. In six mothers the immediate reaction to the control solution was greater than half of the reaction to schistosomal antigen; they were excluded from the analysis of immediate reactions. The reactions were read at 15 min for immediate hypersensitivity and the induration was read at 24 hours for delayed hypersensitivity, following MORIEARTY & LEWERT (1974). The reactions were outlined and transferred to millimeter paper for surface estimation. Following the “Behringwerk AG” instructions, immediate reactions were considered positive in adults when the area covered 100 mm2 or more, and in children as doubtful positive when the area covered from 50 to 100 mm2. For delayed reaction the limits were based on observations in an uninfected group, and the minimal value for positivity in the 24-hour skin
MOTHER-CHILD
606
FIGURE
RELATION
IN HUMAN
SCHISTOSOMIASIS
1
FIGURE
IMMEDIATE SKIN REACTION TO SCHISTOSOMAL ANTIGEN MOTHERS
MANSONI
2
DELAYED SKIN REACTION TO SCHISTOSOMAL ANTIGEN
CHILDREN
CtilLDREN
MOTHERS
L00mm2
1000*
* *
*
* * * **
00 *+ +
*
** * + *+* ** 00
n
* * lk* *
IO
+ *‘lr **
m n n n n
*t * *** + + * * + +
mm n mm n
m
**
mm * *
*
l
n B
a n n
*
n u
**
n
mmmm000000
Mothers
with
positive
skin
reaction
*
Mothers
with
positive
skin
reaction
Sr Mothers
with
negative
skin
reaction
Sr Mothers
with
negative
skin
reaction
W Children
born
to mothers
with
positive
skin
reaction
n Children
born
to mothers
with
positive
0 Children
born
to mothers
with
negative
skin
reaction
0 Children
born
to mothers
with
negative
*
skin skin
reaction reaction
I'. TACHONANDR. BOROJEVIC reaction
was taken to be 10 mm2 (CAMUS et al.,
1977). In vitro techniuue The inhibiiion of leucocyte migration test (MIT) was done followine BENDIXEN & SOBORG
Mother-child relation in human schistosomiasis mansoni : skin test and cord blood reactivity to schistosomal antigens Laboratdrio
Central
PIERRE TACHON AND RADOVAN BOROJEVIC Gonpalo Murk, 121 rua Waldemar Falctlo, Salvador, 77 rue Pasteur, Lyon, France
Summary Reaction to schistosomal antigen was studied in children born to mothers infected with Schistosoma mansoni. Values of immediate (15 min) skin reactions were more elevated and values of delayed (24 h) skin reactions were significantly higher in children born to infected mothers than in children born to uninfected mothers. The macrophage migration inhibition test, done on cord blood cells, was positive to schistosomal antigen in 40 % of children born to infected mothers and negative in all children born to uninfected mothers. These results suggest prenatal sensitization to schistosomal antigen in children born to mothers infected with S. mansoni. Introduction In regions hyperendemic for schistosomiasis mansoni, where levels of infection are above 90%, severe overt disease affects 5 to 25 “,/oof the population. The distribution of severe cases is not random but involves preferentially members of a limited number of families. This familial distribution was described by KLOETZEL (1958) and confirmed recentlv in studies bv 1. C. BINA in the State of Bahia (personal communication). In a homogeneous population familial distribution of severe forms of the disease may be related to microecological, hereditary or congenital factors. Congenital modifications of the immune response to schistosomiasis have been demonstrated in several experimental systems (LEWERT & MANDLOWITZ, 1969; HANG et al., 1974) and its effect on the evolution of the disease has been shown BOROJEVIC et al., 1977). In an earlier study, we demonstrated positive delayed skin reactions to schistosomal antigen in uninfected children born to infected mothers (CAMUS et al.. 1976). The uresent studv was under taken to investigate this phenomenon in new-born children, and thus to differentiate the modifications of an immune response acquired during intrauterine life from those subsequently acquired due to lactation and contact with the local environment. Materials and Methods Population studied 35 parturients and their children, admitted to “Luiz Argollo” Maternity Hospital in SantoAntonio-de-Jesus, state of Bahia, Brazil, were studied. Tb.ev all came from the surroundine rural area, endemic for schistosomiasis mansoni. 26 mothers were infected with Schistosoma mansoni. Schistosomal infection was monitored by stool
Brazil
and Institut
Pasteur,
examination and by immunological methods, i.e. immediate skin reaction (15 min), immunofluorescence and immuno-electrophoresis (carried out on lyophilized sera in the routine diagnostic service of the Institut Pasteur in Lille, France). One stool examination revealed eggs in the faeces of 18 mothers. Repeated stool examinations, often necessary to establish the presence of a light schistosome infection, could not be done. When the immediate skin reaction and at least one serological test were positive, schistosomal infection was presumed as, in young individuals, living continuously in an endemic area, spontaneous cure would not be expected. No mothers had previously had chemotherapy against schistosomiasis. Mothers with a negative stool test and negative immunologically were used as the control group. The mothers’ ages varied from 15 to 44 years and most had had several children. All the women studied appeared in a satisfactory general state and none had overt severe schistosomiasis. All cases with infectious genital diseases were eliminated. 26 babies were born naturally and nine by caesarians. Intestinal parasites are common in this region (Ascaris, Trichuris and Ancylostoma) but no severe infection was observed in the series studied. Eight of the parturients were Negro, six white and the rest were mixed Negro, white and Indian blood, classified as “pardo”, following Brazilian standards. In vivo techniques Skin tests were done on the interior forearm of mothers and on the arm of children. Intradermal injection of 0.05 ml of commercial “Behringwerk AG” schistosomal antigen (total worm extract) was followed by injection of 0.05 ml of “Behringwerk AG” control solution at an adjacent site. In six mothers the immediate reaction to the control solution was greater than half of the reaction to schistosomal antigen; they were excluded from the analysis of immediate reactions. The reactions were read at 15 min for immediate hypersensitivity and the induration was read at 24 hours for delayed hypersensitivity, following MORIEARTY & LEWERT (1974). The reactions were outlined and transferred to millimeter paper for surface estimation. Following the “Behringwerk AG” instructions, immediate reactions were considered positive in adults when the area covered 100 mm2 or more, and in children as doubtful positive when the area covered from 50 to 100 mm2. For delayed reaction the limits were based on observations in an uninfected group, and the minimal value for positivity in the 24-hour skin
MOTHER-CHILD
606
FIGURE
RELATION
IN HUMAN
SCHISTOSOMIASIS
1
FIGURE
IMMEDIATE SKIN REACTION TO SCHISTOSOMAL ANTIGEN MOTHERS
MANSONI
2
DELAYED SKIN REACTION TO SCHISTOSOMAL ANTIGEN
CHILDREN
CtilLDREN
MOTHERS
L00mm2
1000*
* *
*
* * * **
00 *+ +
*
** * + *+* ** 00
n
* * lk* *
IO
+ *‘lr **
m n n n n
*t * *** + + * * + +
mm n mm n
m
**
mm * *
*
l
n B
a n n
*
n u
**
n
mmmm000000
Mothers
with
positive
skin
reaction
*
Mothers
with
positive
skin
reaction
Sr Mothers
with
negative
skin
reaction
Sr Mothers
with
negative
skin
reaction
W Children
born
to mothers
with
positive
skin
reaction
n Children
born
to mothers
with
positive
0 Children
born
to mothers
with
negative
skin
reaction
0 Children
born
to mothers
with
negative
*
skin skin
reaction reaction
I'. TACHONANDR. BOROJEVIC reaction
was taken to be 10 mm2 (CAMUS et al.,
1977). In vitro techniuue The inhibiiion of leucocyte migration test (MIT) was done followine BENDIXEN & SOBORG
