U.S. patent number 5,866,347 [Application Number 08/833,653] was granted by the patent office on 1999-02-02 for method of identifying persons susceptible to autoimmune neuropsychiatric disorders.
This patent grant is currently assigned to The United States of America as represented by the Department of Health and Human Services. Invention is credited to Henrietta L. Leonard, Susan E. Swedo, John B. Zabriskie.
United States Patent |
5,866,347 |
Swedo , et al. |
February 2, 1999 |
**Please see images for:
( Certificate of Correction ) ** |
Method of identifying persons susceptible to autoimmune
neuropsychiatric disorders
Abstract
A method of identifying individuals who have, or who are at risk
of developing, autoimmune neuropsychiatric disorders is disclosed.
The invented method relies on detection of the B lymphocyte
antigen, D8/17. The invented method can conveniently be carried out
as a simple blood test.
Inventors: |
Swedo; Susan E. (McLean,
VA), Leonard; Henrietta L. (Providence, RI), Zabriskie;
John B. (New York, NY) |
Assignee: |
The United States of America as
represented by the Department of Health and Human Services
(Washington, DC)
|
Family
ID: |
23877917 |
Appl.
No.: |
08/833,653 |
Filed: |
April 8, 1997 |
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
473033 |
Jun 6, 1995 |
|
|
|
|
Current U.S.
Class: |
435/7.24;
435/960; 435/7.94; 435/343; 436/501; 435/7.9; 435/7.7; 435/7.2;
435/7.21; 435/7.1; 530/389.6; 530/388.85; 530/388.73; 530/388.7;
530/388.22; 436/811; 436/536; 436/514; 436/506; 435/7.92;
530/391.1; 530/391.3; 435/343.1; 435/7.95; 435/7.93 |
Current CPC
Class: |
G01N
33/56944 (20130101); G01N 33/56972 (20130101); G01N
33/6896 (20130101); G01N 2474/20 (20210801); G01N
2800/301 (20130101); Y10S 436/811 (20130101) |
Current International
Class: |
G01N
33/569 (20060101); G01N 33/68 (20060101); G01N
033/53 (); G01N 033/564 (); G01N 033/543 (); G01N
033/577 () |
Field of
Search: |
;435/7.1,7.21,7.2,7.24,7.7,7.9,7.92,960,7.93,7.94,7.95,334,343,343.1
;436/501,506,514,536,811
;530/388.22,388.7,388.73,388.85,389.6,391.3,391.1 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Allan Gibofsky, MD, JD; John B. Zabriskie, MD; Rheumatic Fever: New
Insights Into An Old Disease, Bulletin on the Rheumatic Diseases,
vol. 42, pp. 5-7, Nov. 1993. .
Susan E. Swedo, MD; Sydenham's Chorea A Model for Childhood
Autoimmune Neuropsychiatric Disorders: JAMA, Dec. 14, 1994 -vol.
272, No. 22, pp. 1788-1791. .
Harvey S. Singer; Neurobiological Issues in Tourette Syndrome;
Brain and Development vol. 16: 353-364, 1994. .
Susan E. Swedo, MD et al.; Sydenham's Chorea: Physical and
Psychological Symptoms of St Vitus Dance; Pediatrics vol. 91 No. 4;
Apr. 1993, pp. 706-713. .
Susan E. Swedo, MD, Henrietta L. Leonard, MD, and Judith L.
Rapoport, MD; Childhood-Onset Obsessive Compulsive Disorder;
Psychiatric Clinic of North America, vol. 15 No. 4; Dec. 1992, pp.
767-775. .
G.V.H. Herdy, J.B. Zabriskie, F. Chapman, A. Khanna and S. Swedo; A
Rapid Test For the Detection of A B-Cell Marker (D8/17) In
Rheumatic Fever Patients, Brazil. J. Med. Biol. Re., 25:789-794,
1992. .
Allan Gibofsky, Ashwani Khanna, Elsa Suh, and John B. Zabriskie;
The Genetics of Rheumatic Fever: Relationship to Streptococcal
Infection and Autoimmune Disease. J. Rheumatol., 18: 1-5, 1991.
.
A. Khanna, D. Buskirk, R. Williams, A. Gibofsky, M. Crow, A. Menon,
M. Fotino, H. Reid, T. Poon-King, P. Rubinstein and J. Zabriskie;
Presence of a non-HLA B Cell Antigen In Rheumatic Fever patients
and their families as defined by a monoclonal antibody. J. Clin.
Invest., 83: 1710-1716, 1989. .
A.J. Allen, M.D., Ph.D., et al.; Case Study: A New
Infectious-Triggered, Autoimmune Subtype of Pediatric OCD and
Tourette's Syndrome; J. Am. Acad. Child Adolesc. Psychiatry, vol.
34, No. 3, Mar. 1995, pp. 307-311. .
Feldman, et al.; J. of Ped., 123:84-86, 1993. .
Seaver, Gen. Eng. News, 14:10,21, 1994..
|
Primary Examiner: Schwadron; Ronald B.
Attorney, Agent or Firm: Knobbe, Martens, Olson & Bear,
LLP
Parent Case Text
This application is a continuation of U.S. application Ser. No.
08/473,033, filed Jun. 6, 1995, now abandoned.
Claims
What is claimed is:
1. A method of determining whether a human subject has
susceptibility to an autoimmune neuropsychiatric disorder other
than Sydenham's chorea, comprising the steps of:
(a) obtaining a sample containing B lymphocytes from the subject;
and
(b) testing the B lymphocytes for the presence of the antigen
recognized by the monoclonal antibody produced by the ATCC HB8783
cell line, wherein the presence of said antigen indicates that the
subject has a susceptibility to said autoimmune neuropsychiatric
disorder.
2. The method of claim 1, wherein said sample containing B
lymphocytes is a blood sample.
3. The method of claim 2, wherein said blood sample is collected
from a finger prick or venous puncture.
4. The method of claim 1, wherein the testing step comprises an
immunohistochemistry assay.
5. The method of claim 1, wherein the testing step comprises
contacting said B lymphocytes with a monoclonal antibody.
6. The method of claim 5, wherein the monoclonal antibody is
produced by the ATCC HB8783 hybridoma cell line.
7. The method of claim 4, wherein the immunohistochemistry assay
comprises microscopy.
8. The method of claim 4, wherein the immunohistochemistry assay
comprises flow cytometry.
9. The method of claim 4, wherein the immunohistochemistry assay is
an ELISA assay.
10. The method of claim 1, wherein said disorder is childhood
obsessive compulsive disorder.
11. The method of claim 1, wherein said disorder is a childhood
onset tic disorder.
12. The method of claim 1, wherein said disorder is childhood onset
Tourette's syndrome.
13. The method of claim 1, wherein said disorder is Attention
Deficit Hyperactivity disorder associated with a GABHS-triggered
autoimmune neuropsychiatric disorder.
14. The method of claim 1, wherein the subject has no prior history
of a neuropsychiatric disorder.
15. The method of claim 1, wherein the neuropsychiatric disorder is
a group A .beta.-hemolytic streptococci (GABHS)-triggered
autoimmune neuropsychiatric disorder.
16. The method of claim 1, wherein the autoimmune neuropsychiatric
disorder is a childhood-onset neuropsychiatric disorder.
Description
FIELD OF THE INVENTION
The present invention relates to a method of identifying persons
with, or at risk of developing, autoimmune neuropsychiatric
disorders. More specifically, the invention relates to the new use
of an antibody-based test for detecting the D8/17 antigen on B
lymphocytes of affected and at risk individuals.
BACKGROUND OF THE INVENTION
Obsessive Compulsive Disorder (OCD) is characterized by recurrent
thoughts (obsessions) and/or repetitive rituals (compulsions) that
are distressful and/or interfere in one's life (American
Psychiatric Association, Diagnostic and Statistical Manual of
Mental Disorders, 4th ed. (DSM-IV), Washington, D.C.: American
Psychiatric Association (1994)). The obsessive thoughts may include
worries about the safety of oneself or family members, past
actions, or fears of contamination. The rituals are often performed
in response to an obsession and include repetitive washing,
checking, counting, repeating, arranging, or hoarding. Childhood
onset OCD has been reviewed by Swedo, et al., in Psychiatric
Clinics of North America 15: 767 (1992). There is no known biologic
marker or genetic marker, despite some evidence that childhood
onset OCD may be biologically based. Lenane, et al., in J. of the
American Academy of Child and Adolescent Psychiatry 29: 407 (1990),
reported that parents of a patient group of children with OCD had
an increased family rate of OCD, suggesting a genetic vulnerability
for some.
Tourette's Syndrome (TS) or Tourette's Disorder is a childhood
onset disorder characterized by involuntary motor and vocal tics of
more than one year's duration which typically change anatomic
location, number, frequency, complexity, and severity over time
(DSM IV). Chronic motor tic, chronic vocal tic, and transient tic
disorders are characterized by the same involuntary motor or vocal
tics, but are not of sufficient duration to meet diagnostic
criteria for TS (DSM-IV). Tic disorders and TS have been reviewed
by Singer, et al., in Brain and Development 16: 353 (1994). There
may be an association between OCD and tic disorders; as children
with OCD have an increased rate of a comorbid (coexisting) tic
disorder (Leonard, et al., Am. J. of Psychiatry 149: 1244 (1992)),
and individuals with TS have an increased rate of obsessive
compulsive symptoms (Pauls et al., Arch. Gen. Psychiatry 43: 1180
(1986)). Additionally, individuals with TS have an increased rate
of familial OCD and tic disorders (Pauls et al., 1986).
Sydenham's Chorea (SC), first described in the late 1600s as "St.
Vitus dance," is a type of rheumatic fever (RF) and is
characterized by muscular weakness and chorea (reviewed by Swedo et
al., in Pediatrics 91: 706 (1993)). The muscle weakness and
adventitious movements may lead to a clumsy gait, slurred speech,
and the inability to hold a grip. Historically, this neurological
disorder has been described to have accompanying psychological
symptoms in some patients, including emotional lability,
irritability, and obsessive compulsive symptoms. Recently, some
children with SC who had accompanying OCD, Attention Deficit
Hyperactivity Disorder, emotional lability, and irritability have
been described (Swedo et al., 1993).
Sydenham's chorea- is a variant of RF that is thought to result
from an autoimmune process mediated by antineuronal antibodies. The
self-reactive antibodies appear to arise in response to group A
.beta.-hemolytic streptococci (GABHS) infections and then
cross-react with antigens on neuronal cells within the basal
ganglia and other brain regions (Husby et al., J. Exp. Med. 144:
1094 (1976)). The choreic symptoms could be caused either directly
by antineuronal antibodies, or indirectly by altering immune
responsivity or permeability of the blood brain barrier.
Significantly, each of these mechanisms is reported to be under
genetic control (Int. Rev. Cytol. 127: 57 (1991)).
SUMMARY OF THE INVENTION
One aspect of the invention provides a method of determining
whether a human subject has susceptibility to an infection
triggered autoimmune neuropsychiatric disorder. The invented method
includes the steps of first obtaining a sample containing B
lymphocytes from the subject, and then testing the B lymphocytes
for the presence of alloantigen D8/17. The presence of the D8/17
antigen on the B lymphocytes indicates that the subject has a
susceptibility to autoimmune neuropsychiatric disorders. In one
embodiment, the sample containing B lymphocytes is a blood sample
that is collected from a finger prick or by venous puncture.
In a preferred embodiment, an immunohistochemistry assay is
employed to test the B lymphocytes for the presence of alloantigen
D8/17. This immunohistochemistry assay can employ an antibody
reagent that may be a monoclonal antibody. The monoclonal antibody
can be the monoclonal antibody that is produced by the HB8783
hybridoma cell line. A visible color change may be used to indicate
the presence of this antibody reagent in the immunohistochemistry
assay. Further, the assay can be performed such that either
microscopy or flow cytometry is employed as a detection system. In
still another embodiment of the immunohistochemistry assay, an
ELISA assay is used to test the subject's B lymphocytes for the
presence of the D8/17 alloantigen.
Other preferred embodiments of the invented method regard the
neuropsychiatric disorders for which susceptibility is being
tested. In one preferred embodiment, the invented method is used
for determining if the subject has susceptibility to an infection
triggered autoimmune childhood obsessive compulsive disorder. In
another preferred embodiment, the invented method is used for
determining if the subject has susceptibility to an infection
triggered autoimmune childhood onset tic disorder. In another
preferred embodiment, the invented method is used for determining
if the subject has susceptibility to infection triggered autoimmune
childhood onset Tourette's syndrome. In another preferred
embodiment, the invented method is used for determining if the
subject has susceptibility to infection triggered autoimmune
Attention Deficit Hyperactivity Disorder. In yet another preferred
embodiment, the invented method is used when the subject has no
prior history of a neuropsychiatric disorder.
DETAILED DESCRIPTION OF THE INVENTION
We have discovered that an antibody-based test for detecting the
presence of the D8117 B lymphocyte alloantigen can be used to
identify pediatric patients with a clinical picture of abrupt onset
or exacerbation of neuropsychiatric symptoms following an
infectious illness, specifically GABHS, and others who are at-risk
of developing such disorders. Identification of this at-risk
population is important because the autoimmune response that
exacerbates these patients' neuropsychiatric disorders is
controllable. For example, early treatment of streptococcal
infections with antibiotics can limit the body's need to mount a
vigorous immune response. For those having the genetic
vulnerability to develop antineuronal antibodies, such intervention
might block development of the symptoms or exacerbation. This
effectively blunts increases in neuropsychiatric symptoms, such as
obsessions, compulsions, tics, inattentiveness or others, brought
on by the production of an anti-strep humoral immune response.
Under a contemplated regimen of preventive care, periodic throat
cultures for asymptomatic GABHS infections are carried out with
appropriate treatment of individuals having positive cultures.
Further, individuals who are at risk of autoimmune neuropsychiatric
symptoms can be enrolled in a program of antibiotic prophylaxis in
order to prevent the possible onset of a strep infection that would
exacerbate the patient's condition.
We have recently reported (Allen et al., J. Am. Acad. Child
Adolesc. Psychiatry 34: 307 (1995)) on a subgroup of pediatric
patients with OCD and/or tic disorders having cycles of clinically
significant symptoms distinguished by a sudden, dramatic onset
followed by a slow waning over a period of months. This pattern was
somewhat similar to the course of symptoms in Sydenham's chorea
(Swedo, S.E., JAMA 272: 1788 (1994)). In addition to the choreic
movements, some Sydenham's patients may exhibit tic-like movements.
Indeed, the phenomenon of tic exacerbation has recently been
addressed by Kiessling, et al., (Pediatrics 92: 39 (1993)) in a
report on patients having increased tics after a community outbreak
of streptococcal pharyngitis.
These observations led us to investigate whether streptococcal
infections, "strep throats" and other infections caused by GABHS,
in pediatric patients could trigger the sudden onset or episodic
worsening of OCD and/or tic disorders, including TS, via an
autoimmune process analogous to Sydenham's chorea (Swedo S.E., JAMA
272: 1788 (1994); Swedo et al., Pediatrics 93: 323 (1994)).
Herein we disclose that immunomodulatory treatments can improve
symptoms for OCD and tic disorder/TS patients having severe illness
that is exacerbated by an autoimmune response. The essential
features of these cases are summarized by the phrase: pediatric,
infection-triggered, autoimmune neuropsychiatric disorders
(PITANDs). As disclosed below, some of these cases may be triggered
by viruses rather than GABHS. A set of subjective criteria for
identifying PITAND cases is also disclosed.
As the result of our work with children in the Child Psychiatry
Branch, National Institute of Mental Health (NIMH) clinic for OCD,
tic disorders (including TS) and attention-deficit hyperactivity
disorder (ADHD), we noted that some children developed the first
onset of, or the acute exacerbation of, neuropsychiatric symptoms
following infectious illness. Some of the children developed abrupt
onset of OCD, tics, and accompanying behavioral and affective
disturbances following GABHS infections. Although each patient had
a diagnosis of OCD and/or tic disorder, some additionally had ADHD,
mood disorders, and anxiety disorders. Some of our clinical
observations of children with neuropsychiatric disorders,
specifically OCD, tic disorders, and ADHD, who had an acute onset
and/or dramatic exacerbation following infectious illness, have
recently been published in J. Am. Acad. Child Adolesc. Psychiatry
34: 307 (1995).
In the following Example, a group of children with OCD, tic
disorders, ADHD, and other neuropsychiatric disorders, who appeared
to have abrupt onset or dramatic onset of neuropsychiatric symptoms
following infectious illness, including GABHS, were sought via
advertisements through professional medical organizations. We
hypothesized that an autoimmune response in children with OCD, tic
disorders, ADHD, and other neuropsychiatric disorders, who
developed acute onset or exacerbation of their infections
subsequent to GABHS or other infections, might underlie the
pathophysiology of the children's neuropsychiatric disorders.
Significantly, the population of children recruited for this study
did not have RF or SC.
Example 1 presents four pediatric cases who were treated in an
open. National Institute of Mental Health (NIMH) trial.
Significantly, these cases represented a subclass of children
having OCD and/or tic disorders whose neuropsychiatric symptoms
were exacerbated following infection.
EXAMPLE 1
A New Infection-Triggered, Autoimmune Subtype of Pediatric OCD and
Tourette's Syndrome: Four Case Studies
Case 1
B. J. was a 14year-old with a 1.5-year history of OCD and mild tics
which had been stable for several months while he was taking a
combination of clomipramine and fluoxetine. Then, during a summer
soccer camp, his OCD symptoms suddenly worsened dramatically. On
his return home a throat culture was done. The culture was positive
and GABHS pharyngitis was diagnosed, although B. J.'s last sore
throat had resolved a month earlier. Two weeks later he came to the
NIMH for evaluation. His obsessions included a fear for his own and
his father's safety, a need for symmetry and perfectionistic
concerns. His predominate compulsions were checking behaviors and
exercises (e.g., fingertip pushups) that had to be performed
perfectly or repeated until he was unable to continue. At that
time, more than 90% of his waking hours were occupied by obsessions
and compulsions. Neurological examination revealed motoric
hyperactivity and mild choreiform movements.
Because of the severity of B. J.'s OCD, his suspicious movements,
and his sudden worsening during a streptococcal infection, he was
treated with a series of six plasma exchanges over a period of two
weeks. During this time there was a marked decline in his OCD
symptoms (Table 1). Subjectively, the patient and his family
reported he was "80% better." A magnetic resonance imaging scan
done after four plasma exchanges showed a 25% decrease in the size
of the head of the caudate compared to a scan done before treatment
(Swedo et al., Pediatrics 93: 323 (1994)). After plasmapheresis he
began a regimen of penicillin as prophylaxis against GABHS
infections. He continued to do well at follow-up several months
later.
Case 2
T. J. was a 10-year-old who had no history of psychiatric or
neurological problems. The weekend after several family members had
the "flu," he experienced a sudden onset of severe obsessions about
viruses and chemicals. He additionally began compulsive
hand-washing. After a month of continuous illness, psychiatric
treatment was sought and he started sertraline therapy, with only
partial symptom relief of his OCD after two months. He was then
evaluated at the NIMH (three months after the onset of his
illness). At that time his forearms and hands were chapped and red,
and contamination fears prevented him from fully opening his mouth
so that he was unable to eat in the hospital or have a throat
culture.
Because of the abrupt onset of his symptoms and their severity, T.
J. was treated with six plasma exchanges over a period of two
weeks. Penicillin prophylaxis was not prescribed because his
episode of OCD appeared to have been virally triggered. His
symptoms declined noticeably during plasmapheresis--after the
fourth exchange he could eat at the hospital and permitted a throat
culture. His symptoms were so improved one month after
plasmapheresis that his sertraline dosage was being tapered, with
only subclinical obsessions and compulsions remaining (Table 1). He
was reported to be doing well several months later.
Case 3
In 1987, when S. J. was seven years old, painful ulcers developed
on his mouth and lips, and he was noted to have a positive
antinuclear antibody titer with speckled pattern. Shortly after
this, he had the first of many GABHS infections, which continued
until 1989 when he had a tonsillectomy. After the surgery he began
to experience motor tics (craning of his neck, eye-blinking,
shoulder-shrugging) and vocal tics ("clicking" sounds), which were
eventually diagnosed as TS. His tics declined after he began to
take a low dose of fluphenazine and were stable for approximately
18 months. Shortly after a bout of the "flu," his tics escalated
dramatically. Of particular concern were new, violet tics of his
head and neck that were so extreme that S. J. had physical
discomfort. Now 13 years old, he was referred to NIMH for
evaluation. He was found to have an antinuclear antibody titer of
1:320 (speckled pattern), and subsequently a transient rash
developed. A rheumatologist concluded that he did not have lupus,
however.
Six months after his viral illness, S. J. was treated with
immunosuppressive doses of prednisone. A clinically significant
improvements in his tics were evident two weeks later (Table 1),
although residual movement remained. His tics again worsened
suddenly a few weeks later, after a viral respiratory infection and
an allergic reaction to an influenza immunization. A retrial of
prednisone at that time was unsuccessful.
Case 4
J. J. was a 13-year-old with a long history of asthma,
hyperactivity, TS and OCD. He had previously been enrolled in
several protocols at the National Institutes of Health (NIH) for
these illnesses. His neuropsychiatric symptoms were believed to be
episodic but had been relatively well controlled for about six
months while he was taking a combination of methylphenidate and
clomipramine. After a documented case of GABHS pharyngitis, he
experienced rapid, severe worsening of both his TS and OCD. This
occurred during a family trip to Thailand and Arizona, during which
the family had to alter their travel plans because of J. J.'s
obsessive fears that the plane would crash. J. J. also had severe
vocal tics (spitting and nearly continuous screaming) during the
trans-Pacific flights, and he was unable to finish any reading
material because he felt the need to reread every sentence many
times.
Approximately 2.5 months after his infection and a month after his
symptoms increased, he was treated with intravenous immunoglobulin
(1 mg/kg per day for two days). His parents reported that his tics
began to improve within a week of the intravenous immunoglobulin
treatment. At one month follow-up Table 1), there was a clinically
significant improvement in his tics, but his OCD was essentially
unchanged. His parents reported that J. J. was doing well several
months later, at which time he entered a NIH protocol comparing
penicillin with placebo as prophylaxis against neuropsychiatric
episodes triggered by GABHS infections.
Table 1 summarizes the relevant findings, treatments and results
from the four case studies presented above.
TABLE 1
__________________________________________________________________________
Demographic, Clinical and Treatment Data Case 1 (B.J.) Case 2
(T.J.) Case 3 (S.J.) Case 4 (J.J.)
__________________________________________________________________________
Sex, age (years) Male, 14 Male, 10 Male, 13 Male, 13 Diagnosis Mild
motor and OCD TS ADHD, TS, OCD (including vocal tics, OCD
(contamination) (contamina- predominate (exercise, need for tion,
rereading, need obsessions and perfection) for perfection)
compulsions) Prodromal Yes No Yes Yes symptoms or prior episodes
Suspected infectious GABHS pharyngitis Viral, possibly Viral,
possibly GABHS pharyngitis trigger for treatment (positive culture)
influenza influenza (positive culture) episode Duration of episode
2 weeks 3 months 5 months 1 month before treatment Laboratory
results ASO = 340 ASO, ANA negative ASO = 240 ASO, ANA negative
before treatment Anti-DNAse B = ANA positive, 1:340 1:320, speckled
ANA negative Pretreatment C-YBOCS = 40 C-YBOCS = 25 Ex MTR = 13
C-YBOCS = 28 ratings.sup.a (maximum possible Ex VTR = 2 Ex MTR = 9
score) Hx MTR = 18 Ex VTR = 12 Hx VTR = 5 Hx MTR = 16 Hx VTR = 19
Treatment Plasmapheresis Plasmapheresis Prednisone IVIG
Posttreatment C-YBOCS = 19.5 C-YBOCS = 10 Ex MTR = 8 C-YBOCS = 26
ratings.sup.b (% change (-51%) (-60%) (-38%) (-7%) from
pretreatment) Ex VTR = 2 (0%) Ex MTR = 4 Hx MTR = 10 (-56%) (-44%)
Ex VTR = 4 Hx VTR = 0 (-67%) (-100%) Hx MTR = 6 (-62%) Hx VTR = 12
(-37%)
__________________________________________________________________________
Note: OCD = Obsessivecompulsive disorder; TS = Tourette's syndrome;
ADHD = attentiondeficit hyperactivity disorder; GABHS = Group A
hemolytic streptococci; ASO = antistreptolysin O; AntiDNAse B =
antistreptococcal DNAse B; ANA = antinuclear antibodies; CYBOCS =
Children's YaleBrown Obsessive Compulsive Scale (Goodman et al.,
Psychiatr. Clin. North Am. 15:861 (1992)) (a score of 20 reflects
OCD symptoms of moderate severity; scores range from 0 to 40); Ex
MTR = Examiner's motor tic ratings on the Shapiro tic rating scale
(Shapiro et al., Gilles de la Tourette Syndrome New York: Raven
Press (1978)) (a score of 12 reflects tics of moderate severity;
scores range from 0 to 20); Ex VTR = examiner's vocal tic ratings
on the Shapiro tic rating scale (Shapiro et al., Gilles de la
Tourette Syndrome New York: Raven Press (1978)); Hx MTR =
historical (fro parent/child) motor tic ratings on the Shapiro tic
rating scale (Shapiro tic ratings on the Shapiro tic rating scale
(Shapiro et al., 1978): IVIG intravenous immunoglobulin. .sup.a All
ratings shown are the means from two physicians with training in
mental health research. .sup.b Posttreatment ratings are within a
month of completing treatment.
The following subjective criteria can be used to accurately
identify PITAND patients:
1. Pediatric onset: symptoms of the disorder first become evident
between three years of age and the beginning of puberty.
2. At some time in his or her life, the patient must have met
diagnostic criteria for OCD and/or a tic disorder.
3. The onset of clinically significant symptoms must be sudden
(with or without a subclinical prodrome), and/or there must be a
pattern of sudden, recurrent, clinically significant symptoms
exacerbations and remissions. Onset of a specific episode typically
can be assigned to a particular day or week, at which time symptoms
seemed to "explode" in severity.
4. Increased symptoms should not occur exclusively during stress or
illness, should be pervasive, should be of sufficient severity to
suggest the need for treatment modifications, and (if untreated)
should last at least four weeks before improvement is noted.
5. During OCD and/or tic exacerbations, the majority of patients
will have an abnormal neurological examination, frequently with
adventitious movements (e.g., mild chorea).
6. There must be evidence of an antecedent or concomitant
infection. Such evidence might include a positive throat culture,
positive streptococcal serological findings (e.g.,
anti-streptolysin O or anti-streptococcal DNAse B), or a history of
illness (e.g., pharyngitis, sinusitis, or flu-like symptoms).
7. Patients may or may not continue to have clinically significant
symptoms between episodes of their OCD and/or tic disorder.
Given our identification of a population of children having a
disorder with a unique symptomology, we investigated a comparison
between pediatric OCD/tic disorders/TS patients whose symptoms had
onset or exacerbation after GABHS infection and SC patients. These
clinical observations of SC, OCD, and tic disorders led us to test
whether a D8/17 immunoassay could be used to identify individuals
afflicted with, or at risk of developing, autoimmune
neuropsychiatric disorders including OCD and/or tic disorders. A
test for the D8/17 B lymphocyte alloantigen is the subject of U.S.
Pat. No. 4,743,538. The monoclonal antibody, D8/17, appears to
identify a cell-surface marker which shows increased expression on
B cells of rheumatic fever patients (Khanna et al., J. Clin.
Invest. 83: 1710 (1989)). The hybridoma producing monoclonal
antibody was deposited with the American Type Culture Collection,
12301 Parklawn Drive, Rockville, Md. 20852 on Apr. 16, 1985 under
accession number HB8783. This deposit was converted to a deposit
under the Budapest Treaty on Jan. 16, 1997. This B cell alloantigen
marker is present ("positive") in 90-100% of patients with RF
(Gibofsky et al., J. Rheumatol (supp. 130) 18: 1-5 (1991)). The
D8/17 antigen is unique to individuals who have had (or had risk
for) RF illness and is considered to be a genetic marker for
individuals who are genetically vulnerable to develop RF. An
individual who had more than 12% (mean plus one standard deviation
above normal values) of their B (DR) cells exhibiting the D8/17
marker was labeled "positive". An individual with less than 12% of
their B (DR) cells exhibiting this marker was considered
"negative." The % positive D8/17 cells was calculated as [(D8/17
positive cells)/(DR cells)].times.100 (Gibofsky et al., 1991).
Ninety to 95% of healthy persons have less then 12% of their B
cells positive for the D8/17 marker, and therefore are considered
negative for this marker (Gibofsky et al., 1991). Rodrigues, et al.
(Pathogenic Streptococci Present and Future, Lancer Publication,
St. Petersburg, Russia (1994)) reported that, of 1,854 healthy
school-aged children in Mexico who were randomly tested for the
marker, only 5% were found to be D8/17 positive. A small proportion
of normals (5-10%) will be D8/17 positive, but among patients with
rheumatic fever, 95% will be positive for the marker. This
indicated an abnormal expansion of the population of D8/17 positive
B cells and increased susceptibility to RF (Gibofsky et al.,
1991).
Importantly, the presence of streptococcal infection per se was not
associated with an increased number of B cells staining positive
for D8/17 antigen in individuals with streptococcal infections but
without rheumatic fever. Specifically, patients with well
documented poststreptococcal glomerulonephritis and others with
documented GABHS tonsillitis did not have positive results for the
D8/17 marker (Kemeny et al., Clin. Immunology and Immunopathology
72: 35 1994; Khanna et al., 1989).
We discovered that a blood test that identified RF susceptibility
also identified individuals susceptible to autoimmune OCD/tic
disorders. In view of the fact that the children participating in
this study did not have RF or SC, one could not have predicted in
advance that these children would be D8/17 positive.
With respect to the immunohistochemical methods useful in
identifying D8/17 positive individuals, variations on the
techniques disclosed below will be apparent to those having
ordinary skill in the art. For instance, while light microscopy was
employed to detect positively staining cells in the following
Example, we anticipate that other techniques such as flow cytometry
and ELISA procedures could be adapted for use with the present
invention. Additionally, we have found that blood samples obtained
either by venous puncture or finger prick methods can be used with
the following procedure.
Example 2 describes the method used to detect the D8/17 positive B
cell antigen in blood samples from children whose neuropsychiatric
symptoms were exacerbated following infectious illness.
Example 2
Immunodetection of the D8/17 Antigen in Blood Samples
Immunohistochemical analysis of blood samples was performed
according to standard laboratory procedures. A description of the
monoclonal antibody used for detecting the D8/17 B cell antigen can
be found in U.S. Pat. No. 4,743,538, the disclosure of which is
hereby incorporated by reference.
A 300 .mu.l sample of citrated blood was transferred to a
polystyrene tube, such as a FALCON 2058. A 100 .mu.l volume of the
D8/17 antibody produced by hybridoma HB8783 was added to the blood
sample and then incubated for 1 hour at 4.degree. C. The mixture
was washed once using 2 mls of PBS-BSA buffer and centrifuged at
1500 rpm for 5 minutes to gently pellet the cells. A 1 liter
preparation of the PBS-BSA buffer contained 8 g of NaCl, 400 mg of
KCl, 1.15 g of Na.sub.2 HPO.sub.4, 10 g of bovine serum albumin, 1
g sodium azide, and was adjusted to a pH of 7.4. After this first
wash step, 20 .mu.l of fluorescein isothiocyanate (FITC) conjugated
goat anti-mouse IgM was added and incubated for 45 minutes at
4.degree. C. The mixture was then washed as before to remove
unbound antibodies. Next, 15 .mu.l of phycoerythrin conjugated
anti-human HLA-DR antibody was added and incubated for 20 minutes
at 4.degree. C. The mixture was again washed as before. A 3 ml
volume of lysis buffer was added and mixed thoroughly. The mixture
was incubated for 3-4 minutes before a 3 minute centrifugation at
1000 rpm. Lysis buffer was prepared by combining 0.9 g NH.sub.4 Cl,
0.19 g KHCO.sub.3, 0.05 ml 10% EDTA and diluting to a final volume
of 100 ml using distilled water. The lysate was washed twice as
before, and then counted for stained cells by standard laboratory
procedures as would be familiar to one having ordinary skill in the
art.
Results of this immunohistochemical analysis from subjects at the
NIMH are shown below in Table 2. Of the SC patients, 89% were
positive for the B cell D8/17 marker. This result was expected
based on the fact that U.S. Pat. No. 4,743,538 indicates the D8/17
antigen is a marker for the risk of developing RF, and that SC is a
variant of RF. Also expected, only 10% of the normal controls were
positive for the D8/17 antigen. This is consistent with previous
estimates that only 5-10% of the population may express this
marker. As hypothesized, 93% of the children with GABHS mediated
(nonRF, nonSC) neuropsychiatric symptoms were D8/17 positive.
Diagnoses of these patients included OCD and/or a tic disorder with
some additionally having ADHD, an anxiety disorder, a mood
disorder, or some behavior disorder. This was significantly
increased over the value that would be expected in a random
population. Nothing in the clinical presentation of the symptoms
suggested that these children should have had such a high rate of
the marker; thus, this is a novel clinical application of the
technique.
TABLE 2 ______________________________________ Frequency of
Individuals Positive for Expression of B cell D8/17 Marker in
Various Patient Populations % of Population Patient Population
D8/17 Positive ______________________________________ Normal
Control 10 Sydenham's Chorea 89 GABHS-mediated (non-RF; non-SC) 93
Neuropsychiatric Symptoms
______________________________________
We have also obtained evidence that the D8/17 marker has predictive
value in identifying individuals who, while unaffected at the time
of testing, may go on to develop autoimmune neuropsychiatric
disorders in the future. More specifically, some of the unaffected
siblings of the D8/17 positive pediatric patients were tested for
the presence of the D8/17 marker. Two siblings of separate patients
were found to be D8/17 positive and subsequently developed OCD
and/or tics. In addition, one proband with OCD had two male
siblings, one with TS (already diagnosed) who was D8/17 positive
and one who was D8/17 negative and evidenced no neuropsychiatric
symptoms.
We have demonstrated that a positive test for the D8/17 antigen can
identify individuals who have OCD, tic disorders/TS, and/or other
autoimmune neuropsychiatric disorders. Further, a positive test for
the D8/17 antigen has been shown to identify individuals at genetic
risk for these disorders. Thus, the D8/17 test has diagnostic and
prognostic implications and may be useful in the prevention of
these neuropsychiatric disorders, as well as identifying patients
for whom novel therapies may be useful. With estimates that 1% of
all children and adolescents have OCD, and that 5-10% have a tic
disorder, this technique will have application in a large number of
individuals.
* * * * *