Expression and sequences of T cell receptor γ and δ chain genes in the thymus of radiation bone marrow chimeras

118 A-33

enhance the subsequent complement mediated lysisof the cells.Evaluation of the immunological functionsof these classIlbearing keratinocyteshasrevealedthatthe classIIkeratinocytem&c&scan not potentin thisregard.

u~regulatecertainimmunologicreactionsbutare

ative

response in an allospecific

response, they can induce a secondary

T cell line.

In addition,

However,

fragment of pigeon

cytochrome

process

positive, restricted generate cells

but not class cytolytic

protein

c to a hybridoma, antigens.

II negative.

indicating

that. although antigenic

also can serve

these

peptides.

as targets

cells

Class

II

for class

11

Since class II bearing keratinocytesonly weakly

as is seen

a chemical

antigen specific

are able to present a peptide

can present

we are currently

unresponsiveness

using

they

keratinocytes

T cell clones.

T cell activation

induce

antigens

native

these same keratinocytes

attempting

when

crosslinker

to determine

(l-ethyl

3-(3

whether

are coupled

splenocytes

such

with peptide

dimethylaminopropyl)

car.

boniimide (ECDI) or when class II molecules and antigenare incorporatedintoplanar membranes.

A-31

Resultsof these studieswillbe discussed.

MOLECULAR AND IMMUNOLOGICAL ANALYSIS FUNCTION-ASSOCIATED MOLECULES

OF MURINE

K. Okumura, H. Yagita, and Y. Shinkai. Juntendo Univ. Sch. of Med.

Dept.

OF THY-l+

T. Tezuka (Kinki University, of Dermatology)

DEM)RITIC

School

LYMPHOCYTE

of Medicine,

We have recently show" that Thy-l+DEC expressed T cell antigen But the function of Thy-l+DEC is not receptor, TCRl y6 chain. By using the assay system of MLR (Mixed clear still now. Lymphocyte Reaction) to know the Natural supressor function, the "roliferatio" of responder was measured under the condition with Respbnder cells which come from BALB/c, C3H and co-stimulator. C57BL/6 were used in MLR with 5~10~ irradiated (2000 rads) C57BL/6 or BALB/c stimulator spleen cells. YETY245, TEHY245, TEHY93 were cell lines which derived from Thy-l+DEC. These Thy-l+DEC lines, EL4, YACl and spleen cells of several mice strains were used for co-stimulator cells. In the results, Thy-l+DEC cell lines suppressed the allo-MLR about 50-90% in all combination of MLR, but control cell lines and spleen cells did not suppressed the MLR. Take" together with data indicating Thy-l+DEC cell lines have a significant suppressor function, Thy-l+DEC cell would have Natural suppressor function.

A-31

HETEROGENEITY

OF DENDRITIC

EPIDERMAL

CELLS

H. Hashizume. M. Takigawa, M. Yamada. Department of Dermatology, Hamamatsu University School of Medicine, Hamamatsu

of 1mmunol.

It has been well known that T cells are essential effecters of immunity to foreign antigens as well as regulators of cellular and humoral immune responses. Recent study of molecular isxwnology revealed that T cells require several important surface structures that contribute to cell-cell interaction in addition to antigen specific T cell receptors. We have been focusing murine lymphocyte function-associated antigens such as CD2 and CD8 which participate in the process of fhymocyte interaction with thymic stromal cells, T cell interaction with antigen-presenting cells, cytotoxic cell recognition of target cells. Since no monoclonal anti-murine CD2 had been available until now, there had been many limitations in studying the role of CD2 molecules in well developed murine experimental systems. However, by utilizing transfectant of mouse CD2 cDNA which we cloned, various types of monoclonal anti-murine CD2 became available in our lab. Here, we would like to introduce our study to examine their roles in T cell functions as well as in T cell differentiation by using established monoclonal antibodies.

Two types of dendritic cells reside in murine epidermis. One type is the Langerhans cell which acts as antigen presenting The other is Thy-l' dendritic epidermal cells(Thy-1' DEC). cells. While this type of cells seems to be involved in immune reactions occurring in the epidermis, the exact role which these cells play is still unknown. By using immunofluorescence methods we studied ontogenical development of Thy-l+ DEC. The number of Thy-l+ DEC was small in the abdominal epidermis of young mice and w?.s increased as mice grew older, to attain the level of adult mice at the age of 4 weeks. Double immunofluorescence studies with the use of fluoresceinated antianti-rabbit Thy-l+ antibody and anti-asialo GM1 plus rhodaminated IgG antibodies showed the presence of both asialo GMl+. Thy-l- and In accordance with asialoGMl+, Thy-l+ cells in young mice. advance in age, the former type decreased in number while cells with the latter phenotype were the sole population among DEC Our results suggest heterogeneity of DEC. expressing asialo GMl.

A-35 A-32

EXPRESSION CHAIN

GENES

AND

SEQUENCES

IN THE

OF

T

THYMUSOF

CELL

RECEPTOR BONE

RADIATION

7 AND

6

MARROW

CHIMERAS Y. Yoshikai, munology.

K. Kishihara,

ENHANCED ANTIGEN-PRESENTING CAPACITY OF LANGERHANS CELLS IS ASSOCIATED WITH MARKEDLY INCNEASED OF Ia ANTIGEN S.SHIMADA, S.U.CAUGHMAN, Department of Dermatology,

G. Matsuzaki

and K. Nom&o.

Medical Institute of Bioregulation.

Department

Kyushu University,

of Im.

Fukuoka, Japan.

Tw distinct types of T cell receptor (TcR) have been identified; a hetercdimer of LI and p chains and a hetercdimer of T and I chains. To understand the molecular mzhanisns of T cell differentiation in adult thymes, we examined the expression of TzR genes in the tiPUS An ordered expressio" of 8 ,T of radiation bone rarrcw chimeras. a chain ge"es similar to seen in the fetalTcel1 the" @, differentiation occurred in the thynus of irradiated mice at the wwever, nucleotide early stage afterbonerrarrcw transplantation. sequence analysis revealed that the repertoires of VI and Vs genes used in the thms of thechinrxaweredifferentfra"those seen ill the fetalthynus. The differences between adult and fetal ti@c develqxent 'chat are observed in radiation bsne nwxcw chiwras IMY be important in our understanding of T cell differentiation'in these mice.

that

EPIDERMAL

prolife~

class 11 bearingkeratinocytes

are unable to presentnativepeptidemolecules to classIIrestricted. T cell hybridomas.

cannot

H. Yamada, Department

For example, although these class 11bearing keratinocytes

cannot generate a primary allogeneic

NATURAL SUPPRESSOR FUNCTION CELL (THY-~+DEc) LINES

S.O.StLARROW and S.I.KATZ. Yamanashi Medical College,

CULTURED EXPR!ZSSION

Yamanashi

and NIH, U.S.A. Recent studies indicate that when epidermal Langerhans cells prepared LC, (LC) are cultured, they, in comparison to freshly stimulate markedly enhanced ability to T cell exhibit In this study, we determined whether proliferative responses. cultured IC enhance antigen-specific T cell responses, and whether such enhanced stimulatory capacity correlates with the level of Ia antigen expressed on LC. We used both the trinitrophenyl-specific T cell clones, which were assayed for (W)TdR incorporation, and the pigeon cytochrome c specific hybridoma, which was assayed for Cultured LC induced IO to 100 times greater IL-Z production. proliferation or IL-Z production by responder cells than did freshly prepared LC. The intensity of I-AX and I-E”, expressed on cultured LC as assessed by flow cytometry, was found to be IO to 36 times greater on a per cell basis than that on freshly prepared LC. The results suggest that when LC are removed from their usual epidermal milieu, they express increased amounts of Ia and become more potent stimulators of T cell responses.