Dinitrochlorobenzene (
DNCB) induced
delayed hypersensitivity but no
eosinophilia in guinea-pigs from two colonies.
Citraconic anhydride (CA) induced
delayed hypersensitivity and
eosinophilia of the blood and bone marrow, and sites of skin tests were also infiltrated by eosinophils. In adoptive transfer of lymphocytes separated from peritoneal exudate cells of strain XIII-sensitized donors, lymphocytes from
DNCB-sensitized guinea-pigs transferred
antigen-specific
delayed hypersensitivity; lymphocytes from CA-sensitized guinea-pigs transferred
delayed hypersensitivity, and induced
eosinophilia of the blood and bone marrow of the recipients. Treatment of the lymphocytes before transfer with antilymphocyte (thymocyte)
globulin or
puromycin suppressed the manifestations in the recipients; normal
globulin did not. Active sensitization with
DNCB induced formation of small amounts, and with CA larger amounts of anaphylactic antibody. Sera from the actively sensitized animals elicited no significant
eosinophilia of blood or bone marrow in one group of recipients. Passive
anaphylaxis elicited a transient
eosinophilia of the blood, but not of the bone marrow. It is postulated that T-helper cells interact with B-lymphocyte precursors, particularly
IgE B cells, to stimulate eosinopoeisis. This results in a reserve of mature eosinophils that may be released in any subsequent anaphylactic event.